Commit graph

1031 commits

Author SHA1 Message Date
Peter Maydell 0fc6e2c183
target/arm: Add some comments in Thumb decode
Add some comments to the Thumb decoder indicating what bits
of the instruction have been decoded at various points in
the code.

This is not an exhaustive set of comments; we're gradually
adding comments as we work with particular bits of the code.

Backports commit a2d12f0f34e9c5ef8a193556fde983aa186fa73a from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell ca5d7b8fd2
target/arm: Add v8M stack checks on ADD/SUB/MOV of SP
Add code to insert calls to a helper function to do the stack
limit checking when we handle these forms of instruction
that write to SP:
* ADD (SP plus immediate)
* ADD (SP plus register)
* SUB (SP minus immediate)
* SUB (SP minus register)
* MOV (register)

Backports commit 5520318939fea5d659bf808157cd726cb967b761 from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell b2146058c3
target/arm: Move v7m_using_psp() to internals.h
We're going to want v7m_using_psp() in op_helper.c in the
next patch, so move it from helper.c to internals.h.

Backports commit 5529bf188d996391ff52a0e1801daf9c6a6bfcb0 from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell ae4900fba2
target/arm: Define new EXCP type for v8M stack overflows
Define EXCP_STKOF, and arrange for it to cause us to take
a UsageFault with CFSR.STKOF set.

Backports commit 86f026de22d8854eecc004af44895de74225794f from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell 8b3b548961
target/arm: Define new TBFLAG for v8M stack checking
The Arm v8M architecture includes hardware stack limit checking.
When certain instructions update the stack pointer, if the new
value of SP is below the limit set in the associated limit register
then an exception is taken. Add a TB flag that tracks whether
the limit-checking code needs to be emitted.

Backports commit 4730fb85035e99c909db7d14ef76cd17f28f4423 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 66ffb372e7
target/arm: Pass TCGMemOpIdx to sve memory helpers
There is quite a lot of code required to compute cpu_mem_index,
or even put together the full TCGMemOpIdx. This can easily be
done at translation time.

Backports commit 500d04843ba953dc4560e44f04001efec38c14a6 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 606e8cdb8c
target/arm: Rewrite vector gather first-fault loads
This implements the feature for softmmu, and moves the
main loop out of a macro and into a function.

Backports commit 116347ce20bb7b5cac17bf2b0e6f607530b50862 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 1cd3c2a408
target/arm: Split contiguous stores for endianness
We can choose the endianness at translation time, rather than
re-computing it at execution time.

Backports commit 28d57f2dc59c287e1c40239509b0a325fd00e32f from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson c9569b3fe0
target/arm: Split contiguous loads for endianness
We can choose the endianness at translation time, rather than
re-computing it at execution time.

Backports commit 7d0a57a2e1cea188b9023261a404d7a211117230 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 2542ad17d0
target/arm: Rewrite vector gather stores
This fixes the endianness problem for softmmu, and moves
the main loop out of a macro and into an inlined function.

Backports commit 78cf1b886aa1b95c97fc5114641515c2892bb240 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson ff63807164
target/arm: Rewrite vector gather loads
This fixes the endianness problem for softmmu, and moves
the main loop out of a macro and into an inlined function.

Backports commit d4f75f25b43041e7a46d12352b3c70ae457d8cea from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 966ea163a3
target/arm: Rewrite helper_sve_st[1234]*_r
This fixes the endianness problem for softmmu, and moves the
main loop out of a macro and into an inlined function

Backports commit 9fd46c8362e0a45d04ccceae7051d06dd65c1d57 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 4978d77039
target/arm: Rewrite helper_sve_ld[234]*_r
Use the same *_tlb primitives as we use for ld1.

For linux-user, this hoists the set of helper_retaddr. For softmmu,
hoists the computation of the current mmu_idx outside the loop,
fixes the endianness problem, and moves the main loop out of a
macro and into an inlined function.

Backports commit f27d4dc2af0de9b7b45c955882b8420905c6efe8 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 5b88176e1d
target/arm: Rewrite helper_sve_ld1*_r using pages
Uses tlb_vaddr_to_host for correct operation with softmmu.
Optimize for accesses within a single page or pair of pages.

Backports commit 9123aeb6fcb14e0955ebe4e2a613802cfa0503ea from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 935eb43b5e
target/arm: Clear unused predicate bits for LD1RQ
The 16-byte load only uses 16 predicate bits. But while
reusing the other load infrastructure, we find other bits
that are set and trigger an assert. To avoid this and
retain the assert, zero-extend the predicate that we pass
to the LD1 helper.

Backports commit 2a99ab2b3545133961de034df27e24f4c22e3707 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson a37f24aa11
target/arm: Adjust aarch64_cpu_dump_state for system mode SVE
Use the existing helpers to determine if (1) the fpu is enabled,
(2) sve state is enabled, and (3) the current sve vector length.

Backports commit ced3155141755ba244c988c72c4bde32cc819670 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 87c20b52c0
target/arm: Handle SVE vector length changes in system mode
SVE vector length can change when changing EL, or when writing
to one of the ZCR_ELn registers.

For correctness, our implementation requires that predicate bits
that are inaccessible are never set. Which means noticing length
changes and zeroing the appropriate register bits.

Backports commit 0ab5953b00b3165877d00cf75de628c51670b550 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 2fb9c4c41d
target/arm: Pass in current_el to fp and sve_exception_el
We are going to want to determine whether sve is enabled
for EL other than current.

Backports commit 2de7ace292cf7846b0cda0e940272d2cb0e06859 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 00fc5d43fd
target/arm: Adjust sve_exception_el
Check for EL3 before testing CPTR_EL3.EZ. Return 0 when the exception
should be routed via AdvSIMDFPAccessTrap. Mirror the structure of
CheckSVEEnabled more closely.

Fixes: 5be5e8eda78

Backports commit 60eed0869d68b91eff71cc0a0facb01983726a5d from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 1081e5e7a4
target/arm: Define ID_AA64ZFR0_EL1
Given that the only field defined for this new register may only
be 0, we don't actually need to change anything except the name.

Backports commit 9516d7725ec1deaa6ef5ccc5a26d005650d6c524 from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell d82046cafc
target/arm: Don't read r4 from v8M exception stackframe twice
A cut-and-paste error meant we were reading r4 from the v8M
callee-saves exception stack frame twice. This is harmless
since it just meant we did two memory accesses to the same
location, but it's unnecessary. Delete it.

Backports commit e5ae4d0c063fbcca4cbbd26bcefbf1760cfac2aa from qemu
2018-10-08 14:15:15 -04:00
Peter Maydell f628cbdfc3
target/arm: Correct condition for v8M callee stack push
In v7m_exception_taken() we were incorrectly using a
"LR bit EXCRET.ES is 1" check when it should be 0
(compare the pseudocode ExceptionTaken() function).
This meant we didn't stack the callee-saved registers
when tailchaining from a NonSecure to a Secure exception.

Backports commit 7b73a1ca05b33d42278ce29cea4652e22d408165 from qemu
2018-10-08 14:15:15 -04:00
Lioncash b62e892b20
mips: Use DisasContext for parameters in place of TCGContext where applicable
This is more future-friendly with qemu's main repo, as it's more
generic.
2018-10-06 04:37:28 -04:00
Lioncash 47b45f1bc2
arm: Take DisasContext as a parameter instead of TCGContext where applicable
This is more future-friendly with qemu, as it's more generic.
2018-10-06 04:17:12 -04:00
Lioncash 766c70f608
arm: Move cpu_M0 to DisasContext 2018-10-06 03:32:39 -04:00
Lioncash 787fd448b1
arm: Move cpu_V1 to DisasContext 2018-10-06 03:28:42 -04:00
Lioncash 1aa20da917
arm: Move cpu_V0 to DisasContext 2018-10-06 03:26:52 -04:00
Lioncash 06c21baaa4
arm: Move cpu_F1d to DisasContext 2018-10-06 03:11:54 -04:00
Lioncash 5f3dd68f9c
arm: Move cpu_F0d to DisasContext 2018-10-06 03:07:42 -04:00
Lioncash e457ce8ccc
arm: Move cpu_F1s to DisasContext 2018-10-06 03:02:06 -04:00
Lioncash a4f23de55f
arm: Move cpu_F0 to DisasContext
Decreases the size of the TCGContext struct for targets that don't need
to use this variable.
2018-10-06 02:58:11 -04:00
Peter Maydell 04fead0dcb
target/arm: Start AArch32 CPUs with EL2 but not EL3 in Hyp mode
The ARMv8 architecture defines that an AArch32 CPU starts
in SVC mode, unless EL2 is the highest available EL, in
which case it starts in Hyp mode. (In ARMv7 a CPU with EL2
but not EL3 was not a valid configuration, but we don't
specifically reject this if the user asks for one.)

Backports commit 060a65df056a5d6ca3a6a91e7bf150ca1fbccddf from qemu
2018-09-25 21:19:44 -04:00
Richard Henderson 994038c817
target/arm: Fix cpu_get_tb_cpu_state() for non-SVE CPUs
Not only are the sve-related tb_flags fields unused when SVE is
disabled, but not all of the cpu registers are initialized properly
for computing same. This can corrupt other fields by ORing in -1,
which might result in QEMU crashing.

This bug was not present in 3.0, but this patch is cc'd to
stable because adf92eab90e3f5f34c285 where the bug was
introduced was marked for stable.

Backports commit e79b445d896deb61909be52b61b87c98a9ed96f7 from qemu
2018-09-25 21:17:32 -04:00
Lioncash e81fa596bc
target/arm/cpu: Use type_register instead of type_register_static() in arm_cpu_register_types()
The lifetime of the TypeInfo instance doesn't live indefinitely, so we
should be using the regular type_register().
2018-09-03 17:34:08 -04:00
MerryMage 9b87d0f61a unicorn_arm: Allow for read/write of UC_ARM_REG_FPSCR 2018-09-03 21:03:55 +01:00
MerryMage a13d51f756 unicorn_aarch64: Use aa64_vfp_qreg instead of aa32_vfp_dreg 2018-09-03 07:47:40 +01:00
MerryMage 896a8e1320 unicorn_arm: Use ARM offset not ARM64 offset
Was introduced by 5439b4a542
2018-09-03 07:44:29 +01:00
Peter Maydell 39045d67df
target/arm: Remove a handful of stray tabs
Following the bulk conversion of the iwMMXt code, there are
just a handful of hard coded tabs in target/arm; fix them.
This is a whitespace-only patch.

Backports commit 6e0fafe2ef02378c696e7cf84ef41511e3b3b81a from qemu
2018-08-25 04:34:44 -04:00
Peter Maydell 1b8534bf31
target/arm: Untabify iwmmxt_helper.c
Untabify the arm iwmmxt_helper.c. This affects only the iwMMXt code.
We've never touched that code in years, so it's not going to get
fixed up by our "change when touched" process, and a bulk change is
not going to be too disruptive.

This commit was produced using Emacs "untabify" (plus one
by-hand removal of a space to fix a checkpatch nit); it is
a whitespace-only change.

Backports commit 67aed15551f9814712d5ac25a155919b34fbd627 from qemu
2018-08-25 04:33:44 -04:00
Peter Maydell 3619f707a6
target/arm: Clear CPSR.IL and CPSR.J on 32-bit exception entry
On 32-bit exception entry, CPSR.J must always be set to 0
(see v7A Arm ARM DDI0406C.c B1.8.5). CPSR.IL must also
be cleared on 32-bit exception entry (see v8A Arm ARM
DDI0487C.a G1.10).

Clear these bits. (This fixes a bug which will never be noticed
by non-buggy guests.)

Backports commit 829f9fd394ab082753308cbda165c13eaf8fae49 from qemu
2018-08-25 04:28:22 -04:00
Peter Maydell 16477f908e
target/arm: Implement support for taking exceptions to Hyp mode
Implement the necessary support code for taking exceptions
to Hyp mode in AArch32.

Backports commit b9bc21ff9f9bb2d841adf1dc7f6f8ddfb9ab8b5e from qemu
2018-08-25 04:27:18 -04:00
Peter Maydell 4c445c2300
target/arm: Factor out code for taking an AArch32 exception
Factor out the code which changes the CPU state so as to
actually take an exception to AArch32. We're going to want
to use this for handling exception entry to Hyp mode.

Backports commit dea8378bb3e86f2c6bd05afb3927619f7c51bb47 from qemu
2018-08-25 04:23:53 -04:00
Peter Maydell c238d5cc6b
target/arm: Implement AArch32 HCR and HCR2
The AArch32 HCR and HCR2 registers alias HCR_EL2
bits [31:0] and [63:32]; implement them.

Since HCR2 exists in ARMv8 but not ARMv7, we need new
regdef arrays for "we have EL3, not EL2, we're ARMv8"
and "we have EL2, we're ARMv8" to hold the definitions.

Backports commit ce4afed8396aabaf87cd42fbe8a4c14f7a9d5c10 from qemu
2018-08-25 04:21:57 -04:00
Peter Maydell cc57e03da4
target/arm: Implement RAZ/WI HACTLR2
The v8 AArch32 HACTLR2 register maps to bits [63:32] of ACTLR_EL2.
We implement ACTLR_EL2 as RAZ/WI, so make HACTLR2 also RAZ/WI.
(We put the regdef next to ACTLR_EL2 as a reminder in case we
ever make ACTLR_EL2 something other than RAZ/WI).

Backports commit 0e0456ab8895a5e85998904549e331d36c2692a5 from qemu
2018-08-25 04:13:37 -04:00
Richard Henderson 241fb78efc
target/arm: Use the float-to-int-scale softfloat routines
Backports commit 323cd490845acf663159ca26e35cb977ad9b85a2 from qemu
2018-08-25 04:11:51 -04:00
Richard Henderson 7d3ad3e053
target/arm: Use the int-to-float-scale softfloat routines
Backports commit b9b903cf245e4df1199cc7b2b80381ef85a6b1ab from qemu
2018-08-25 04:07:43 -04:00
Peter Maydell 214dadf7e7
target/arm: Implement AArch32 ERET instruction
ARMv7VE introduced the ERET instruction, which is necessary to
return from an exception taken to Hyp mode. Implement this.
In A32 encoding it is a completely new encoding; in T32 it
is an adjustment of the behaviour of the existing
"SUBS PC, LR, #<imm8>" instruction.

Backports commit 55c544ed2709bd202e71e77ddfe3ea0327852211 from qemu
2018-08-22 12:56:14 -04:00
Peter Maydell 8c41572624
target/arm: Permit accesses to ELR_Hyp from Hyp mode via MSR/MRS (banked)
The MSR (banked) and MRS (banked) instructions allow accesses to ELR_Hyp
from either Monitor or Hyp mode. Our translate time check
was overly strict and only permitted access from Monitor mode.

The runtime check we do in msr_mrs_banked_exc_checks() had the
correct code in it, but never got there because of the earlier
"currmode == tgtmode" check. Special case ELR_Hyp.

Backports commit aec4dd09f172ee64c19222b78269d5952fd9c1dc from qemu
2018-08-22 12:51:42 -04:00
Peter Maydell 858aa2d094
target/arm: Implement ESR_EL2/HSR for AArch32 and no-EL2
The AArch32 HSR is the equivalent of AArch64 ESR_EL2;
we can implement it by marking our existing ESR_EL2 regdef
as STATE_BOTH. It also needs to be "RES0 from EL3 if
EL2 not implemented", so add the missing stanza to
el3_no_el2_cp_reginfo.

Backports commit 68e78e332cb1c3f8b0317a0443acb2b5e190f0dd from qemu
2018-08-22 12:48:35 -04:00
Peter Maydell c21d2062e4
target/arm: Implement AArch32 Hyp FARs
The AArch32 virtualization extensions support these fault address
registers:
* HDFAR: aliased with AArch64 FAR_EL2[31:0] and AArch32 DFAR(S)
* HIFAR: aliased with AArch64 FAR_EL2[63:32] and AArch32 IFAR(S)

Implement the accessors for these. This fixes in passing a bug
where we weren't implementing the "RES0 from EL3 if EL2 not
implemented" behaviour for AArch64 FAR_EL2.

Backports commit cba517c31e7df8932c4473c477a0f01d8a0adc48 from qemu
2018-08-22 12:45:23 -04:00
Peter Maydell 763a71a962
target/arm: Implement AArch32 HVBAR
Implement the AArch32 HVBAR register; we can do this just by
making the existing VBAR_EL2 regdefs be STATE_BOTH.

Backports commit d79e0c0608899428281a17c414ccf1a82d86ab85 from qemu
2018-08-22 12:37:12 -04:00
Peter Maydell e9fb085aa1
target/arm: Add missing .cp = 15 to HMAIR1 and HAMAIR1 regdefs
ARMCPRegInfo structs will default to .cp = 15 if they
are ARM_CP_STATE_BOTH, but not if they are ARM_CP_STATE_AA32
(because a coprocessor number of 0 is valid for AArch32).
We forgot to explicitly set .cp = 15 for the HMAIR1 and
HAMAIR1 regdefs, which meant they would UNDEF when the guest
tried to access them under cp15.

Backports commit b5ede85bfb7ba1a8f6086494c82f400b29969f65 from qemu
2018-08-22 12:36:11 -04:00
Peter Maydell 2d2c6982ce
target/arm: Correct typo in HAMAIR1 regdef name
We implement the HAMAIR1 register as RAZ/WI; we had a typo in the
regdef, though, and were incorrectly naming it HMAIR1 (which is
a different register which we also implement as RAZ/WI).

Backports commit 55b53c718b2f684793eeefcf1c1a548ee97e23aa from qemu
2018-08-22 12:33:45 -04:00
Roman Kapl 0e2dc93e5f
target/arm: Fix crash on conditional instruction in an IT block
If an instruction is conditional (like CBZ) and it is executed
conditionally (using the ITx instruction), a jump to an undefined
label is generated, and QEMU crashes.

CBZ in IT block is an UNPREDICTABLE behavior, but we should not
crash. Honouring the condition code is allowed by the spec in this
case (constrained unpredictable, ARMv8, section K1.1.7), and matches
what we do for other "UNPREDICTABLE inside an IT block" instructions.

Fix the 'skip on condition' code to create a new label only if it
does not already exist. Previously multiple labels were created, but
only the last one of them was set.

Backports commit c2d9644e6d517170bf6520f633628259a8460d48 from qemu
2018-08-22 12:27:45 -04:00
Richard Henderson 0136ca773f
target/arm: Fix aa64 FCADD and FCMLA decode
These insns require u=1; failed to include that in the switch
cases. This probably happened during one of the rebases just
before final commit.

Fixes: d17b7cdcf4e

Backports commit b8a4a96db3639e17ab5e5cdc14fca4b19fbf5b3b from qemu
2018-08-17 14:06:01 -04:00
Richard Henderson c387d51c1d
target/arm: Use FZ not FZ16 for SVE FCVT single-half and double-half
We were using the wrong flush-to-zero bit for the non-half input.

Fixes: 46d33d1e3c9

Backports commit e4ab5124a5c2e2291006b24bdc21c3dd8d087ff4 from qemu
2018-08-17 14:05:10 -04:00
Richard Henderson 118495f4b1
target/arm: Use fp_status_fp16 for do_fmpa_zpzzz_h
This makes float16_muladd correctly use FZ16 not FZ.

Fixes: 6ceabaad110

Backports commit 52a339b11d1719a6589de40606859939875fda9a from qemu
2018-08-17 14:04:20 -04:00
Richard Henderson 15a68a354c
target/arm: Ignore float_flag_input_denormal from fp_status_f16
When FZ is set, input_denormal exceptions are recognized, but this does
not happen with FZ16. The softfloat code has no way to distinguish
these bits and will raise such exceptions into fp_status_f16.flags,
so ignore them when computing the accumulated flags.

Backports commit 19062c169e5bcdda3d60df9161228e107bf0f96e from qemu
2018-08-17 14:03:41 -04:00
Richard Henderson f787dd15fd
target/arm: Adjust FPCR_MASK for FZ16
When support for FZ16 was added, we failed to include the bit
within FPCR_MASK, which means that it could never be set.
Continue to zero FZ16 when ARMv8.2-FP16 is not enabled.

Fixes: d81ce0ef2c4

Backports commit 0b62159be33d45d00dfa34a317c6d3da30ffb480 from qemu
2018-08-17 14:02:49 -04:00
Stefan Hajnoczi d2f3a6c0d5
target/arm: add cortex-m0 CPU model
Define a "cortex-m0" ARMv6-M CPU model.

Most of the register reset values set by other CPU models are not
relevant for the cut-down ARMv6-M architecture.

Backports commit 191776b96a381b5d2b8d3f90c1c02b3e4779e5f7 from qemu
2018-08-17 14:01:00 -04:00
Richard Henderson cb11b3a6bd
target/arm: Add sve-max-vq cpu property to -cpu max
This allows the default (and maximum) vector length to be set
from the command-line. Which is extraordinarily helpful in
debugging problems depending on vector length without having to
bake knowledge of PR_SET_SVE_VL into every guest binary.

Backports relevant parts of commit
adf92eab90e3f5f34c285da6d14d48952b7a8e72 from qemu
2018-08-17 13:57:51 -04:00
Richard Henderson 1d3cf8a0b0
target/arm: Dump SVE state if enabled
Also fold the FPCR/FPSR state onto the same line as PSTATE,
and mention but do not dump disabled FPU state.

Backports commit 2bf5f3f91bb4e3faa2a19aec042138a938afbf6a from qemu
2018-08-17 13:52:28 -04:00
Richard Henderson 731bcd194b
target/arm: Fix offset scaling for LD_zprr and ST_zprr
The scaling should be solely on the memory operation size; the number
of registers being loaded does not come in to the initial computation.

Backports commit 50ef1cbf31caad21019ae6fa8036ed6f29244ba5 from qemu
2018-08-17 13:50:59 -04:00
Richard Henderson 86d6bb4d43
target/arm: Fix offset for LD1R instructions
The immediate should be scaled by the size of the memory reference,
not the size of the elements into which it is loaded.

Backports commit d0e372b0298f897993f831dbff7ad4f1c70f138e from qemu
2018-08-17 13:49:39 -04:00
Richard Henderson 7487c66bee
target/arm: Fix sign-extension in sve do_ldr/do_str
The expression (int) imm + (uint32_t) len_align turns into uint32_t
and thus with negative imm produces a memory operation at the wrong
offset. None of the numbers involved are particularly large, so
change everything to use int.

Backports commit 19f2acc915a0f8f443a959844540a6f09133cc96 from qemu
2018-08-17 13:48:44 -04:00
Richard Henderson 1ca7c30fbb
target/arm: Fix typo in helper_sve_ld1hss_r
Backports commit 573ec0fe40b9a412085ac7dfb41975a0fc2b28dd from qemu
2018-08-17 13:47:38 -04:00
Richard Henderson e2e7bb0e21
target/arm: Fix typo in helper_sve_movz_d
Backports commit 054e7adf4e64e4acb3b033348ebf7cc871baa34f from qemu
2018-08-16 07:12:18 -04:00
Lioncash 9a2581aff6
Comment out tailchaining code
Allows build to continue.
2018-08-16 07:11:31 -04:00
Richard Henderson f26356b930
target/arm: Reorganize SVE WHILE
The pseudocode for this operation is an increment + compare loop,
so comparing <= the maximum integer produces an all-true predicate.

Rather than bound in both the inline code and the helper, pass the
helper the number of predicate bits to set instead of the number
of predicate elements to set.

Backports commit bbd0968c458d48e34a08b8694fa3309a9fe1c9e7 from qemu
2018-08-16 07:09:33 -04:00
Lioncash eccda3afcc
target/arm: Fix typo in do_sat_addsub_64
Used the wrong temporary in the computation of subtractive overflow.

Backports commit 7a31e0c6c68baffab0867bdd92b8744568b1d3ba from qemu
2018-08-16 07:06:05 -04:00
Richard Henderson 46fd2c485a
target/arm: Fix sign of sve_cmpeq_ppzw/sve_cmpne_ppzw
The normal vector element is sign-extended before
comparing with the wide vector element.

Backports commit df4e001093988544d09887122ae824f18ba55c68 from qemu
2018-08-16 07:04:52 -04:00
Peter Maydell 8d34a271f6
target/arm: Implement tailchaining for M profile cores
Tailchaining is an optimization in handling of exception return
for M-profile cores: if we are about to pop the exception stack
for an exception return, but there is a pending exception which
is higher priority than the priority we are returning to, then
instead of unstacking and then immediately taking the exception
and stacking registers again, we can chain to the pending
exception without unstacking and stacking.

For v6M and v7M it is IMPDEF whether tailchaining happens for pending
exceptions; for v8M this is architecturally required. Implement it
in QEMU for all M-profile cores, since in practice v6M and v7M
hardware implementations generally do have it.

(We were already doing tailchaining for derived exceptions which
happened during exception return, like the validity checks and
stack access failures; these have always been required to be
tailchained for all versions of the architecture.)

Backports commit 5f62d3b9e67bfc3deb970e3c7fb7df7e57d46fc3 from qemu
2018-08-16 07:03:51 -04:00
Peter Maydell e3be0c4aa6
target/arm: Restore M-profile CONTROL.SPSEL before any tailchaining
On exception return for M-profile, we must restore the CONTROL.SPSEL
bit from the EXCRET value before we do any kind of tailchaining,
including for the derived exceptions on integrity check failures.
Otherwise we will give the guest an incorrect EXCRET.SPSEL value on
exception entry for the tailchained exception.

Backports commit 89b1fec193b81b6ad0bd2975f2fa179980cc722e from qemu
2018-08-16 06:58:34 -04:00
Peter Maydell e044c59cc1
target/arm: Initialize exc_secure correctly in do_v7m_exception_exit()
In do_v7m_exception_exit(), we use the exc_secure variable to track
whether the exception we're returning from is secure or non-secure.
Unfortunately the statement initializing this was accidentally
inside an "if (env->v7m.exception != ARMV7M_EXCP_NMI)" conditional,
which meant that we were using the wrong value for NMI handlers.
Move the initialization out to the right place.

Backports commit b8109608bc6f3337298d44ac4369bf0bc8c3a1e4 from qemu
2018-08-16 06:57:27 -04:00
Peter Maydell c79ebe4965
target/arm: Treat SCTLR_EL1.M as if it were zero when HCR_EL2.TGE is set
One of the required effects of setting HCR_EL2.TGE is that when
SCR_EL3.NS is 1 then SCTLR_EL1.M must behave as if it is zero for
all purposes except direct reads. That is, it effectively disables
the MMU for the NS EL0/EL1 translation regime.

Backports commit 3d0e3080d8b7abcddc038d18e8401861c369c4c1 from qemu
2018-08-16 06:46:09 -04:00
Peter Maydell 12248b8685
target/arm: Provide accessor functions for HCR_EL2.{IMO, FMO, AMO}
The IMO, FMO and AMO bits in HCR_EL2 are defined to "behave as
1 for all purposes other than direct reads" if HCR_EL2.TGE
is set and HCR_EL2.E2H is 0, and to "behave as 0 for all
purposes other than direct reads" if HCR_EL2.TGE is set
and HRC_EL2.E2H is 1.

To avoid having to check E2H and TGE everywhere where we test IMO and
FMO, provide accessors arm_hcr_el2_imo(), arm_hcr_el2_fmo()and
arm_hcr_el2_amo(). We don't implement ARMv8.1-VHE yet, so the E2H
case will never be true, but we include the logic to save effort when
we eventually do get to that.

(Note that in several of these callsites the change doesn't
actually make a difference as either the callsite is handling
TGE specially anyway, or the CPU can't get into that situation
with TGE set; we change everywhere for consistency.)

Backports commit ac656b166b57332ee397e9781810c956f4f5fde5 from qemu
2018-08-16 06:41:45 -04:00
Peter Maydell 3979058dcb
target/arm: Honour HCR_EL2.TGE when raising synchronous exceptions
Whene we raise a synchronous exception, if HCR_EL2.TGE is set then
exceptions targeting NS EL1 must be redirected to EL2. Implement
this in raise_exception() -- all synchronous exceptions go through
this function.

(Asynchronous exceptions go via arm_cpu_exec_interrupt(), which
already honours HCR_EL2.TGE when it determines the target EL
in arm_phys_excp_target_el().)

Backports commit 7556edfb4d7bf0583c852c8cfc49ef494c41dd8a from qemu
2018-08-16 06:41:57 -04:00
Peter Maydell 6b8d98bcd2
target/arm: Honour HCR_EL2.TGE and MDCR_EL2.TDE in debug register access checks
Some debug registers can be trapped via MDCR_EL2 bits TDRA, TDOSA,
and TDA, which we implement in the functions access_tdra(),
access_tdosa() and access_tda(). If MDCR_EL2.TDE or HCR_EL2.TGE
are 1, the TDRA, TDOSA and TDA bits should behave as if they were 1.
Implement this by having the access functions check MDCR_EL2.TDE
and HCR_EL2.TGE.

Backports commit 30ac6339dca3fe0d05a611f12eedd5af20af585a from qemu
2018-08-16 06:41:02 -04:00
Peter Maydell f0bf1160e4
target/arm: Mask virtual interrupts if HCR_EL2.TGE is set
If the "trap general exceptions" bit HCR_EL2.TGE is set, we
must mask all virtual interrupts (as per DDI0487C.a D1.14.3).
Implement this in arm_excp_unmasked().

Backports commit 2ccf0fef632f3d54b2cc9ea08f1e6904ff1f8df4 from qemu
2018-08-16 06:39:27 -04:00
Julia Suvorova 9d7deb2997
arm: Add ARMv6-M programmer's model support
Forbid stack alignment change. (CCR)
Reserve FAULTMASK, BASEPRI registers.
Report any fault as a HardFault. Disable MemManage, BusFault and
UsageFault, so they always escalated to HardFault. (SHCSR)

Backports commit 22ab3460017cfcfb6b50f05838ad142e08becce5 from qemu
2018-08-16 06:36:27 -04:00
Julia Suvorova b67b948feb
target/arm: Forbid unprivileged mode for M Baseline
MSR handling is the only place where CONTROL.nPRIV is modified.

Backports commit def183446cebc0090f6d885383a6502302249f33 from qemu
2018-08-16 06:34:29 -04:00
Peter Maydell 241c561bc3
target/arm: Correctly handle overlapping small MPU regions
To correctly handle small (less than TARGET_PAGE_SIZE) MPU regions,
we must correctly handle the case where the address being looked
up hits in an MPU region that is not small but the address is
in the same page as a small region. For instance if MPU region
1 covers an entire page from 0x2000 to 0x2400 and MPU region
2 is small and covers only 0x2200 to 0x2280, then for an access
to 0x2000 we must not return a result covering the full page
even though we hit the page-sized region 1. Otherwise we will
then cache that result in the TLB and accesses that should
hit region 2 will incorrectly find the region 1 information.

Check for the case where we miss an MPU region but it is still
within the same page, and in that case narrow the size we will
pass to tlb_set_page_with_attrs() for whatever the final
outcome is of the MPU lookup.

Backports commit 9d2b5a58f85be2d8e129c4b53d6708ecf8796e54 from qemu
2018-07-23 19:54:00 -04:00
Richard Henderson bd9975a8ab
target/arm: Fix LD1W and LDFF1W (scalar plus vector)
'I' was being double-incremented; correctly within the inner loop
and incorrectly within the outer loop.

Backports commit 628fc75f3a3bb115de3b445c1a18547c44613cfe from qemu
2018-07-17 12:33:00 -04:00
Peter Maydell 55985b40f8
target/arm: Use correct mmu_idx for exception-return unstacking
For M-profile exception returns, the mmu index to use for exception
return unstacking is supposed to be that of wherever we are returning to:
* if returning to handler mode, privileged
* if returning to thread mode, privileged or unprivileged depending on
CONTROL.nPRIV for the destination security state

We were passing the wrong thing as the 'priv' argument to
arm_v7m_mmu_idx_for_secstate_and_priv(). The effect was that guests
which programmed the MPU to behave differently for privileged and
unprivileged code could get spurious MemManage Unstack exceptions.

Backports commit 2b83714d4ea659899069a4b94aa2dfadc847a013 from qemu
2018-07-10 12:55:59 -04:00
Richard Henderson ee24dff90c
target/arm: Fix do_predset for large VL
Use MAKE_64BIT_MASK instead of open-coding. Remove an odd
vector size check that is unlikely to be more profitable
than 3 64-bit integer stores. Correct the iteration for WORD
to avoid writing too much data.

Fixes RISU tests of PTRUE for VL 256.

Backports commit 973558a3f869e591d2406dd8226ec0c4e32a3c3e from qemu
2018-07-09 16:43:15 -04:00
Richard Henderson 0fb2742a4a
target/arm: Suppress Coverity warning for PRF
These instructions must perform the sve_access_check, but
since they are implemented as NOPs there is no generated
code to elide when the access check fails.

Backports commit 2f95a3b09aebdcb5c9152a7ac434a5d57441fe82 from qemu
2018-07-09 16:40:54 -04:00
Lioncash 0cf14f0d13
target/arm: Fix ISAR6 register state
Bad patch application
2018-07-03 19:31:52 -04:00
Richard Henderson 611bc4e6db
target/arm: Add ID_ISAR6
This register was added to aa32 state by ARMv8.2.

Backports commit 802abf4024d23e48d45373ac3f2b580124b54b47 from qemu
2018-07-03 05:15:47 -04:00
Richard Henderson 0da6b74f69
target/arm: Prune a15 features from max
There is no need to re-set these 3 features already
implied by the call to aarch64_a15_initfn.

Backports commit 0b33968e7f4cf998f678b2d1a5be3d6f3f3513d8 from qemu
2018-07-03 05:09:39 -04:00
Richard Henderson d950e69174
target/arm: Prune a57 features from max
There is no need to re-set these 9 features already
implied by the call to aarch64_a57_initfn.

Backports commit 156a7065365578deb3d63c2b5b69a4b5999a8fcc from qemu
2018-07-03 05:08:47 -04:00
Richard Henderson 6d81235ebb
target/arm: Fix SVE system register access checks
Leave ARM_CP_SVE, removing ARM_CP_FPU; the sve_access_check
produced by the flag already includes fp_access_check. If
we also check ARM_CP_FPU the double fp_access_check asserts.

Backports commit 11d7870b1b4d038d7beb827f3afa72e284701351 from qemu
2018-07-03 05:07:53 -04:00
Richard Henderson f64e48dbee
target/arm: Fix SVE signed division vs x86 overflow exception
We already check for the same condition within the normal integer
sdiv and sdiv64 helpers. Use a slightly different formation that
does not require deducing the expression type.

Backports commit 7e8fafbfd0537937ba8fb366a90ea6548cc31576 from qemu
2018-07-03 05:06:06 -04:00
Aaron Lindsay 27afa92f24
target/arm: Mark PMINTENSET accesses as possibly doing IO
This makes it match its AArch64 equivalent, PMINTENSET_EL1

Backports commit b7d793ad3db06401bc817c0ca355a2d160c802d4 from qemu
2018-07-03 05:05:00 -04:00
Aaron Lindsay 4684e875d3
target/arm: Add ARM_FEATURE_V7VE for v7 Virtualization Extensions 2018-07-03 05:04:08 -04:00
Alex Bennée 85512a5121
target/arm: support reading of CNT[VCT|FRQ]_EL0 from user-space
Since kernel commit a86bd139f2 (arm64: arch_timer: Enable CNTVCT_EL0
trap..), released in kernel version v4.12, user-space has been able
to read these system registers. As we can't use QEMUTimer's in
linux-user mode we just directly call cpu_get_clock().

Backports commit 26c4a83bd4707797868174332a540f7d61288d15 from qemu
2018-07-03 05:00:06 -04:00
Richard Henderson a325de6685
target/arm: Implement ARMv8.2-DotProd
We've already added the helpers with an SVE patch, all that remains
is to wire up the aa64 and aa32 translators. Enable the feature
within -cpu max for CONFIG_USER_ONLY.

Backports commit 26c470a7bb4233454137de1062341ad48947f252 from qemu
2018-07-03 04:55:43 -04:00
Richard Henderson d4a8f1bfcb
target/arm: Enable SVE for aarch64-linux-user
Enable ARM_FEATURE_SVE for the generic "max" cpu.

Backports commit 802ac0e1e956f3b34a7cb0eda4ec28a60aa87a0a from qemu
2018-07-03 04:46:44 -04:00
Richard Henderson d343f8ac0f
target/arm: Implement SVE dot product (indexed)
Backports commit 16fcfdc7325649b187ac489f3ae0b0d2a20b6230 from qemu
2018-07-03 04:42:41 -04:00
Richard Henderson 2f6d555473
target/arm: Implement SVE dot product (vectors)
Backports commit d730ecaae77ac696515207a5ef99509240fc792b from qemu
2018-07-03 04:35:25 -04:00
Richard Henderson 01a7224cdb
target/arm: Implement SVE fp complex multiply add (indexed)
Enhance the existing helpers to support SVE, which takes the
index from each 128-bit segment. The change has no effect
for AdvSIMD, since there is only one such segment.

Backports commit 18fc24057815bf3d956cfab892a2bc2344bd1dcb from qemu
2018-07-03 04:32:46 -04:00
Richard Henderson 281deae0a9
target/arm: Pass index to AdvSIMD FCMLA (indexed)
For aa64 advsimd, we had been passing the pre-indexed vector.
However, sve applies the index to each 128-bit segment, so we
need to pass in the index separately.

For aa32 advsimd, the fp32 operation always has index 0, but
we failed to interpret the fp16 index correctly.

Backports commit 2cc99919a81a62589a4a6b0f365eabfead1db1a7 from qemu
2018-07-03 04:27:10 -04:00
Richard Henderson 63431f0c21
target/arm: Implement SVE fp complex multiply add
Backports commit 05f48bab3080fb876fbad8d8f14e6ba545432d67 from qemu
2018-07-03 04:21:41 -04:00
Richard Henderson 79220741df
target/arm: Implement SVE floating-point complex add
Backports commit 76a9d9cdc481ed79f1c2ec16eeed185f13e6a8ae from qemu
2018-07-03 04:17:41 -04:00
Richard Henderson f7847aad46
target/arm: Implement SVE MOVPRFX
Backports commit a21035822e67000b4849e31935d0ecc39a96bb9f from qemu
2018-07-03 04:14:37 -04:00
Richard Henderson 00d3671412
target/arm: Implement SVE floating-point unary operations
Backports commit ec5b375bb5a0e35c0c21dc9dd1d82894269ce215 from qemu
2018-07-03 04:11:12 -04:00
Richard Henderson 2c2c940ef8
target/arm: Implement SVE floating-point round to integral value
Backports commit cda3c75322c6fae1cc5b367ee6d7acf2cbdbcf2b from qemu
2018-07-03 04:07:21 -04:00
Richard Henderson a9160a0e08
target/arm: Implement SVE floating-point convert to integer
Backports commit df4de1affc440d6f2cdaeea329b90c0b88ece5a1 from qemu
2018-07-03 04:02:58 -04:00
Richard Henderson 524630de27
target/arm: Implement SVE floating-point convert precision
Backports commit 46d33d1e3c9c5d56d57056db55010de52c173902 from qemu
2018-07-03 03:58:07 -04:00
Richard Henderson b14793a933
target/arm: Implement SVE floating-point trig multiply-add coefficient
Backports commit 67fcd9ad35d2b38630ee34e8ced8878d334c74fb from qemu
2018-07-03 03:52:36 -04:00
Richard Henderson f7e0c9e079
target/arm: Implement SVE FP Compare with Zero Group
Backports commit 4d2e2a03384a43c641e0cbca7ac79d7d0c50f666 from qemu
2018-07-03 03:49:52 -04:00
Richard Henderson 942f3c835e
target/arm: Implement SVE Floating Point Unary Operations - Unpredicated Group
Backports commit 3887c0388d39930ab419d4ae6e8ca5ea67a74ad5 from qemu
2018-07-03 03:44:40 -04:00
Richard Henderson f9f228efec
target/arm: Implement SVE FP Fast Reduction Group
Backports commit 23fbe79faa38cb4acc59f956a63feba3c2cc73ac from qemu
2018-07-03 03:41:00 -04:00
Richard Henderson cf3c7824ff
target/arm: Implement SVE Floating Point Multiply Indexed Group
Backports commit ca40a6e6e390eb1cad7ade881dc7c622793f9324 from qemu
2018-07-03 03:35:49 -04:00
Richard Henderson c718ef4243
target/arm: Implement SVE floating-point arithmetic with immediate
Backports commit cc48affe83fff4b2886c064265d7103dee5e4a14 from qemu
2018-07-03 03:24:46 -04:00
Richard Henderson db1d39ab4a
target/arm: Implement SVE floating-point compare vectors
Backports commit abfdefd5bd444b629d16dcefc2b60ac8da37e87d from qemu
2018-07-03 03:14:24 -04:00
Richard Henderson be65f60799
target/arm: Implement SVE scatter store vector immediate
Backports commit 408ecde97bd30f8ec13f831976d0a9a6535bb569 from qemu
2018-07-03 03:09:51 -04:00
Richard Henderson 892a9a66eb
target/arm: Implement SVE first-fault gather loads
Backports commit ed67eb7fa2a63b6709ec94397d833bc3686f7833 from qemu
2018-07-03 03:06:07 -04:00
Richard Henderson 1782f20dde
target/arm: Implement SVE gather loads
Backports commit 673e9fa6c29e030f4ab6ceae5d0f50bd36fe0ee0 from qemu
2018-07-03 02:58:18 -04:00
Richard Henderson 3a5d095277
target/arm: Implement SVE prefetches
Backports commit dec6cf6b43a1e3b18626852064d1e6e863c9b681 from qemu
2018-07-03 02:42:06 -04:00
Richard Henderson b78e283513
target/arm: Implement SVE scatter stores
Backports commit f6dbf62a7e3d00e9a1dcc7fe3e53b32c3ed93e24 from qemu
2018-07-03 02:40:17 -04:00
Richard Henderson d71cdfa41f
target/arm: Implement SVE store vector/predicate register
Backports commit 5047c204d0d4a0fff616a24963b2b45c7d9ba4c4 from qemu
2018-07-03 02:32:10 -04:00
Richard Henderson c497dc0a83
target/arm: Implement SVE load and broadcast element
Backports commit 684598640dc3b28f86ccc28cc9af50ba257f4cc8 from qemu
2018-07-03 02:27:00 -04:00
Richard Henderson 2caa99929e
target/arm: Implement SVE Floating Point Accumulating Reduction Group
Backports commit 7f9ddf64d5fe5bfaa91ae0ec52217d86f4d86452 from qemu
2018-07-03 02:21:41 -04:00
Richard Henderson 44d89b4cb1
target/arm: Implement SVE FP Multiply-Add Group
Backports commit 6ceabaad1101b0b33490b0fd4bed5b6445b0a34e from qemu
2018-07-03 02:17:16 -04:00
Richard Henderson d1c5d5b728
target/arm: Implement SVE floating-point arithmetic (predicated)
Backports commit ec3b87c28eb120b6575cc1ed7bfbfbf1b0060163 from qemu
2018-07-03 02:13:04 -04:00
Richard Henderson e7f53b6d1b
target/arm: Implement SVE integer convert to floating-point
Backports commit 8092c6a314c9625d8976fb6c5b6969f2a1105cd8 from qemu
2018-07-03 02:05:50 -04:00
Richard Henderson 8a99e1bad2
target/arm: Implement SVE load and broadcast quadword
Backports commit 05abe304be2987cb3576729a14dab96e9ccfaec9 from qemu
2018-07-03 02:01:23 -04:00
Richard Henderson 3a51861c05
target/arm: Implement SVE Memory Contiguous Store Group
Backports commit 1a039c7e58533d5f9431a2064771113d5961c964 from qemu
2018-07-03 01:57:52 -04:00
Richard Henderson 22a155a5d4
target/arm: Implement SVE Contiguous Load, first-fault and no-fault
Backports commit e2654d757598d6c06d1ceb25c62ddf7d63cac32f from qemu
2018-07-03 01:52:38 -04:00
Richard Henderson da1eeb226e
target/arm: Implement SVE Memory Contiguous Load Group
Backports commit c4e7c493da2fdd2c92a7958e592e38200af2f1ba from qemu
2018-07-03 01:40:18 -04:00
Peter Maydell 4abcf14b52
target/arm: Handle small regions in get_phys_addr_pmsav8()
Allow ARMv8M to handle small MPU and SAU region sizes, by making
get_phys_add_pmsav8() set the page size to the 1 if the MPU or
SAU region covers less than a TARGET_PAGE_SIZE.

We choose to use a size of 1 because it makes no difference to
the core code, and avoids having to track both the base and
limit for SAU and MPU and then convert into an artificially
restricted "page size" that the core code will then ignore.

Since the core TCG code can't handle execution from small
MPU regions, we strip the exec permission from them so that
any execution attempts will cause an MPU exception, rather
than allowing it to end up with a cpu_abort() in
get_page_addr_code().

(The previous code's intention was to make any small page be
treated as having no permissions, but unfortunately errors
in the implementation meant that it didn't behave that way.
It's possible that some binaries using small regions were
accidentally working with our old behaviour and won't now.)

We also retain an existing bug, where we ignored the possibility
that the SAU region might not cover the entire page, in the
case of executable regions. This is necessary because some
currently-working guest code images rely on being able to
execute from addresses which are covered by a page-sized
MPU region but a smaller SAU region. We can remove this
workaround if we ever support execution from small regions.

Backports commit 720424359917887c926a33d248131fbff84c9c28 from qemu
2018-07-03 00:55:37 -04:00
Peter Maydell 5e8e8b9bf8
target/arm: Set page (region) size in get_phys_addr_pmsav7()
We want to handle small MPU region sizes for ARMv7M. To do this,
make get_phys_addr_pmsav7() set the page size to the region
size if it is less that TARGET_PAGE_SIZE, rather than working
only in TARGET_PAGE_SIZE chunks.

Since the core TCG code con't handle execution from small
MPU regions, we strip the exec permission from them so that
any execution attempts will cause an MPU exception, rather
than allowing it to end up with a cpu_abort() in
get_page_addr_code().

(The previous code's intention was to make any small page be
treated as having no permissions, but unfortunately errors
in the implementation meant that it didn't behave that way.
It's possible that some binaries using small regions were
accidentally working with our old behaviour and won't now.)

Backports commit e5e40999b5e03567ef654546e3d448431643f8f3 from qemu
2018-07-03 00:49:51 -04:00
Julia Suvorova f28514178a
target/arm: Strict alignment for ARMv6-M and ARMv8-M Baseline
Unlike ARMv7-M, ARMv6-M and ARMv8-M Baseline only supports naturally
aligned memory accesses for load/store instructions.

Backports commit 2aeba0d007d33efa12a6339bb140aa634e0d52eb from qemu
2018-06-29 14:15:33 -05:00
Julia Suvorova 65d0e176c3
target/arm: Introduce ARM_FEATURE_M_MAIN
This feature is intended to distinguish ARMv8-M variants: Baseline and
Mainline. ARMv7-M compatibility requires the Main Extension. ARMv6-M
compatibility is provided by all ARMv8-M implementations.

Backports commit cc2ae7c9de14efd72c6205825eb7cd980ac09c11 from qemu
2018-06-29 14:14:18 -05:00
Edgar E. Iglesias dfc6bd6a0b
target-arm: Add the Cortex-R5F
Add the Cortex-R5F with the optional FPU enabled.

Backports commit ebac5458c7517ed7b8ee06eb90beacc7472b295d from qemu
2018-06-29 13:53:31 -05:00
Julia Suvorova 38747fc125
target/arm: Minor cleanup for ARMv6-M 32-bit instructions
The arrays were made static, "if" was simplified because V7M and V8M
define V6 feature.

Backports commit 8297cb13e407db8a96cc7ed6b6a6c318a150759a from qemu
2018-06-29 13:50:30 -05:00
Julia Suvorova f447a6f668
target/arm: Allow ARMv6-M Thumb2 instructions
ARMv6-M supports 6 Thumb2 instructions. This patch checks for these
instructions and allows their execution.
Like Thumb2 cores, ARMv6-M always interprets BL instruction as 32-bit.

This patch is required for future Cortex-M0 support.

Backports commit 14120108f87b3f9e1beacdf0a6096e464e62bb65 from qemu
2018-06-15 14:12:20 -04:00
Richard Henderson d81cc5f5cd
target/arm: Implement SVE Floating Point Arithmetic - Unpredicated Group
Backports commit 29b80469dc51ae4064e9ef9223967882d2610523 from qemu
2018-06-15 14:10:16 -04:00
Richard Henderson e56db70fee
target/arm: Implement SVE Integer Wide Immediate - Unpredicated Group
Backports commit 6e6a157d683058d86a224cf128320d67b0915365 from qemu
2018-06-15 14:05:11 -04:00
Richard Henderson b5352c6ba1
target/arm: Implement FDUP/DUP
Backports commit ed49196125360c037d7f23c1c315a85cc234e72d from qemu
2018-06-15 13:56:03 -04:00
Richard Henderson 496bb35c97
target/arm: Implement SVE Integer Compare - Scalars Group
Backports commit caf1cefc72be98497e0907d0e07f4327fc641e96 from qemu
2018-06-15 13:54:05 -04:00
Richard Henderson bc55b3e570
target/arm: Implement SVE Predicate Count Group
Backports commit 9ee3a611de28b8d0862fa687215b04b5aad20747 from qemu
2018-06-15 13:49:58 -04:00
Richard Henderson bb930f35b0
target/arm: Implement SVE Partition Break Group
Backports commit 35da316f5e847292ffbe7b6d16cd3988043dfe22 from qemu
2018-06-15 13:42:35 -04:00
Richard Henderson ade246e87b
target/arm: Implement SVE Integer Compare - Immediate Group
Backports commit 38cadeba0daf0f16cf2aeaa5b2752b26fb0676c5 from qemu
2018-06-15 13:35:40 -04:00
Richard Henderson 2969a38d61
target/arm: Implement SVE Integer Compare - Vectors Group
Backports commit 757f9cff1b63895bfd6fc8d66a6e52d7c40baa7b from qemu
2018-06-15 13:29:15 -04:00
Richard Henderson 7211d415a4
target/arm: Implement SVE Select Vectors Group
Backports commit d3fe4a29d754dee73cbf3cb7584db222981179ac from qemu
2018-06-15 13:17:47 -04:00
Richard Henderson 7698c1634e
target/arm: Implement SVE vector splice (predicated)
Backports commit b48ff24098c72f86e187e6abb7e9ca4de40a7fb4 from qemu
2018-06-15 13:14:33 -04:00
Richard Henderson 7d930e8515
target/arm: Implement SVE reverse within elements
Backports commit dae8fb9019d2aa6ccb151a19871df40de6c98e29 from qemu
2018-06-15 13:12:14 -04:00
Richard Henderson 53d151de58
target/arm: Implement SVE copy to vector (predicated)
Backports commit 792a557847697235037fea30eaaacb9b45b4c9e5 from qemu
2018-06-15 13:03:36 -04:00
Richard Henderson 0bb2fdd752
target/arm: Implement SVE conditionally broadcast/extract element
Backports commit ef23cb726dc32375bc2fca7ac3e9f34816f6ee13 from qemu
2018-06-15 13:01:40 -04:00
Richard Henderson 8ba3bde59b
target/arm: Implement SVE compress active elements
Backports commit 3ca879aeb3412bc2be35d01a7bedf5fada960b5d from qemu
2018-06-15 12:52:19 -04:00
Richard Henderson d9ed221567
target/arm: Implement SVE Permute - Interleaving Group
Backports commit 234b48e9c68759aea78ff5a1e49c2ba806cd1d83 from qemu
2018-06-15 12:49:42 -04:00
Richard Henderson 3722ab310b
target/arm: Implement SVE Permute - Predicates Group
Backports commit d731d8cb3c74258669211f065c918353eb7b8f4a from qemu
2018-06-15 12:44:50 -04:00
Richard Henderson c57ff23c56
target/arm: Implement SVE Permute - Unpredicated Group
Backports commit 30562ab716bcec0bf718b47b5268949856b17604 from qemu
2018-06-15 12:37:56 -04:00
Richard Henderson 4dc2b5ea79
target/arm: Extend vec_reg_offset to larger sizes
Rearrange the arithmetic so that we are agnostic about the total size
of the vector and the size of the element. This will allow us to index
up to the 32nd byte and with 16-byte elements.

Backports commit 66f2dbd783d0b6172043e3679171421b2d0bac11 from qemu
2018-06-15 12:23:35 -04:00
Philippe Mathieu-Daudé 5992214b3b
target/arm: Add trailing '\n' to qemu_log() calls
Backports commit 0221c8fdf2321137b34bd4dbb2557d0725739822 from qemu
2018-06-08 19:24:38 -04:00
Richard Henderson 10e2b13650
tcg: Pass tb and index to tcg_gen_exit_tb separately
Do the cast to uintptr_t within the helper, so that the compiler
can type check the pointer argument. We can also do some more
sanity checking of the index argument.

Backports commit 07ea28b41830f946de3841b0ac61a3413679feb9 from qemu
2018-06-07 11:56:32 -04:00
Richard Henderson 533a3f6a6c
tcg: Fix helper function vs host abi for float16
Depending on the host abi, float16, aka uint16_t, values are
passed and returned either zero-extended in the host register
or with garbage at the top of the host register.

The tcg code generator has so far been assuming garbage, as that
matches the x86 abi, but this is incorrect for other host abis.
Further, target/arm has so far been assuming zero-extended results,
so that it may store the 16-bit value into a 32-bit slot with the
high 16-bits already clear.

Rectify both problems by mapping "f16" in the helper definition
to uint32_t instead of (a typedef for) uint16_t. This forces
the host compiler to assume garbage in the upper 16 bits on input
and to zero-extend the result on output.

Backports commit 6c2be133a7478e443c99757b833d0f265c48e0a6 from qemu
2018-06-02 10:10:12 -04:00
Peter Maydell 0f0b2e0bd8
target/arm: Honour FPCR.FZ in FRECPX
The FRECPX instructions should (like most other floating point operations)
honour the FPCR.FZ bit which specifies whether input denormals should
be flushed to zero (or FZ16 for the half-precision version).
We forgot to implement this, which doesn't affect the results (since
the calculation doesn't actually care about the mantissa bits) but did
mean we were failing to set the FPSR.IDC bit.

Backports commit 2cfbf36ec07f7cac1aabb3b86f1c95c8a55424ba from qemu
2018-06-02 10:02:57 -04:00
Richard Henderson 6835b2dd13
target/arm: Implement SVE Permute - Extract Group
Backports commit b94f8f60bd841c5b737185cd38263e26822f77ab from qemu
2018-05-20 05:26:55 -04:00
Richard Henderson 9917f0d536
target/arm: Implement SVE Integer Wide Immediate - Predicated Group
Backports commit f25a2361539626721dbccce14c077cad03b2e72c from qemu
2018-05-20 05:24:04 -04:00
Richard Henderson f4ecf1a152
target/arm: Implement SVE Bitwise Immediate Group
Backports commit e1fa1164f397bbd381439ed32d97d9b4b4d7eb43 from qemu
2018-05-20 05:17:53 -04:00
Richard Henderson 89038c1e4b
target/arm: Implement SVE Element Count Group
Backports commit 24e82e68341e73ec0f65534c78c13fd03395b188 from qemu
2018-05-20 05:15:35 -04:00
Richard Henderson 0249ab3f7e
target/arm: Implement SVE floating-point trig select coefficient
Backports commit a1f233f25fd502f9a5b40c14df1b4dbdda463487 from qemu
2018-05-20 05:05:20 -04:00
Richard Henderson d6c18fc788
target/arm: Implement SVE floating-point exponential accelerator
Backports commit 0762cd428fd7b471207f5cb5b4bd4bd8f141dbe0 from qemu
2018-05-20 05:01:16 -04:00
Richard Henderson cb55a3acdb
target/arm: Implement SVE Compute Vector Address Group
Backports commit 4b242d9c1b6beaf5c81d84e956243b614a4a1d84 from qemu
2018-05-20 04:57:18 -04:00
Richard Henderson 45e009269e
target/arm: Implement SVE Bitwise Shift - Unpredicated Group
Backports commit d9d78dccc86eed10ccf1c8e1ac236e41ec330b06 from qemu
2018-05-20 04:51:58 -04:00
Lioncash bf97c44a2b
target/arm: Implement SVE Stack Allocation Group 2018-05-20 04:45:53 -04:00
Richard Henderson 45a09e2f25
target/arm: Implement SVE Index Generation Group
Backports commit 9a56c9c3a955b77fe436beef7ac03c76a65fa32d from qemu
2018-05-20 04:43:01 -04:00
Richard Henderson 390bd68287
target/arm: Implement SVE Integer Arithmetic - Unpredicated Group
Backports commit fea98f9c3077e4666f6d4933030b5891fbd6bb12 from qemu
2018-05-20 04:36:54 -04:00
Richard Henderson 1730d3cff0
target/arm: Implement SVE Integer Multiply-Add Group
Backports commit 96a36e4a44bbf296ac212ed68ebf4e48d3dfb1f0 from qemu
2018-05-20 04:35:36 -04:00
Richard Henderson 32949156d2
target/arm: Implement SVE Integer Arithmetic - Unary Predicated Group
Backports commit afac6d0467c1327ad2e30a3c35347fcf5a773742 from qemu
2018-05-20 04:31:18 -04:00
Lioncash 878b862a04
target/arm: Implement SVE bitwise shift by wide elements (predicated) 2018-05-20 03:10:24 -04:00
Richard Henderson 5aa51a3a74
target/arm: Implement SVE bitwise shift by vector (predicated)
Backports commit 27721dbb7ae5e2a52f06588cf38854e4cbc613c0 from qemu
2018-05-20 03:07:02 -04:00
Richard Henderson 7bb3067b95
target/arm: Implement SVE bitwise shift by immediate (predicated)
Backports commit ccd841c3d71db6943f8b6d3d56bd2abb548ba40c from qemu
2018-05-20 03:01:07 -04:00
Richard Henderson 837e39ea63
target/arm: Implement SVE Integer Reduction Group
Excepting MOVPRFX, which isn't a reduction. Presumably it is
placed within the group because of its encoding.

Backports commit 047cec971d2791b206677b954227ea92ff7ee3db from qemu
2018-05-20 02:53:04 -04:00
Richard Henderson 331aabddeb
target/arm: Implement SVE Predicate Misc Group
Backports commit 028e2a7b876631eff165cac59eb43bdb2dcc213b and
f97cfd596ed9bd38644323cb61d19b85ac703c81 from qemu
2018-05-20 02:43:36 -04:00
Richard Henderson 65f74e3608
target/arm: Implement SVE Predicate Logical Operations Group
Backports commit 516e246a1a292f6c6f6aad5451799accbb08acd9 from qemu
2018-05-20 01:35:59 -04:00
Lioncash 1eaa2e4571
target/arm: Implement SVE predicate test 2018-05-20 01:16:16 -04:00
Richard Henderson e6a0b2c2bc
target/arm: Implement SVE Bitwise Logical - Unpredicated Group
These were the instructions that were stubbed out when
introducing the decode skeleton.

Backports commit 39eea56172e668cc4cca611ed9166779df54ac63 from qemu
2018-05-20 01:00:52 -04:00
Richard Henderson 49def4bbde
target/arm: Add SVE decode skeleton
Including only 4, as-yet unimplemented, instruction patterns
so that the whole thing compiles.

Backports commit 38388f7ee3adc04a7e7246c04352451c4f8d00fb from qemu
2018-05-20 00:48:14 -04:00
Richard Henderson d2d8e2fc33
target/arm: Introduce translate-a64.h
Move some stuff that will be common to both translate-a64.c
and translate-sve.c.

Backports commit 8c71baedb8055beaa681823206ee3a74f9f8649a from qemu
2018-05-20 00:34:25 -04:00
Abdallah Bouassida 11149ba82b
target/arm: Add _S suffix to the secure version of a sysreg
This is a preparation for the coming feature of creating dynamically an XML
description for the ARM sysregs.
Add "_S" suffix to the secure version of sysregs that have both S and NS views
Replace (S) and (NS) by _S and _NS for the register that are manually defined,
so all the registers follow the same convention.

Backports commit 9c513e786d85cc58b8ba56a482566f759e0835b6 from qemu
2018-05-20 00:19:34 -04:00
Abdallah Bouassida 079615b2a0
target/arm: Add ARM_CP_NO_GDB as a new bit field for ARMCPRegInfo type
This is a preparation for the coming feature of creating dynamically an XML
description for the ARM sysregs.
A register has ARM_CP_NO_GDB enabled will not be shown in the dynamic XML.
This bit is enabled automatically when creating CP_ANY wildcard aliases.
This bit could be enabled manually for any register we want to remove from the
dynamic XML description.

Backports commit 1f16378718fa87d63f70d0797f4546a88d8e3dd7 from qemu
2018-05-20 00:15:56 -04:00
Richard Henderson 1b6cac4e7e
target/arm: Remove floatX_maybe_silence_nan from conversions
This is now handled properly by the generic softfloat code.

Backports commit a9d173dc603af74102c24c1c92d479ba580bbf07 from qemu
2018-05-19 23:23:09 -04:00
Richard Henderson 5e532f6d20
target/arm: Use floatX_silence_nan when we have already checked for SNaN
Backports commit d7ecc062c4e264f716ed239df931f52adb340508 from qemu
2018-05-19 23:21:28 -04:00
Alex Bennée 50105cf593
target/arm: squash FZ16 behaviour for conversions
The ARM ARM specifies FZ16 is suppressed for conversions. Rather than
pushing this logic into the softfloat code we can simply save the FZ
state and temporarily disable it for the softfloat call.

Backports commit 0acb9e7cb341cd767e39ec0875c8706eb2f1c359 from qemu
2018-05-19 23:00:09 -04:00
Alex Bennée 40d57900bf
target/arm: convert conversion helpers to fpst/ahp_flag
Instead of passing env and leaving it up to the helper to get the
right fpstatus we pass it explicitly. There was already a get_fpstatus
helper for neon for the 32 bit code. We also add an get_ahp_flag() for
passing the state of the alternative FP16 format flag. This leaves
scope for later tracking the AHP state in translation flags.

Backports commit 486624fcd3eaca6165ab8401d73bbae6c0fb81c1 from qemu
2018-05-19 22:58:25 -04:00
Alex Bennée 070276faf6
target/arm: Fix sqrt_f16 exception raising
We are meant to explicitly pass fpst, not cpu_env.

Backports commit 905edee9101c54cda5b72286b7f7607cf1c3c4d1 from qemu
2018-05-15 22:29:54 -04:00
Alex Bennée f8e1f71df9
target/arm: Implement FMOV (immediate) for fp16
All the hard work is already done by vfp_expand_imm, we just need to
make sure we pick up the correct size.

Backports commit 6ba28ddb9be37bdb67e3e38007a53ccbdcd010df from qemu
2018-05-15 22:28:46 -04:00
Alex Bennée cd76e7aaaa
target/arm: Implement FCSEL for fp16
These were missed out from the rest of the half-precision work.

Backports commit ace97feef3613194900d4eb9ffc6819b840fbaeb from qemu
2018-05-15 22:26:53 -04:00
Alex Bennée 80074e4745
target/arm: Implement FCMP for fp16
These where missed out from the rest of the half-precision work.

Backports commit 7a1929256ea1a03df12625e75ed571c60dca5bfb from qemu
2018-05-15 22:24:39 -04:00
Richard Henderson eeab666292
target/arm: Implement FP data-processing (3 source) for fp16
We missed all of the scalar fp16 fma operations.

Backports commit 95f9864fde6078e2d2c036a07cc4fe44f199be96 from qemu
2018-05-15 22:19:42 -04:00
Richard Henderson a614dbb3c7
target/arm: Implement FP data-processing (2 source) for fp16
We missed all of the scalar fp16 binary operations.

Backports commit b8f5171cf01420a9f0ee895c5591e9b9914f391a from qemu
2018-05-15 22:14:43 -04:00
Richard Henderson 60dfdb724b
target/arm: Introduce and use read_fp_hreg
Backports commit 3d99d931266eaeaf7e83703a53f32232cd6faad7 from qemu
2018-05-15 22:10:51 -04:00
Richard Henderson 9b42d01480
target/arm: Implement FCVT (scalar, fixed-point) for fp16
Backports commit 2752728016bef06e7c9cfb961019272859beeca4 from qemu
2018-05-15 22:08:07 -04:00
Richard Henderson 8436080518
target/arm: Implement FCVT (scalar, integer) for fp16
Backports commit 564a0632504fad840491aa9a59453f4e64a316c4 from qemu
2018-05-15 22:06:49 -04:00
Richard Henderson 75643ab1cf
target/arm: Early exit after unallocated_encoding in disas_fp_int_conv
No sense in emitting code after the exception.

Backports commit 8c738d430796edeae5e13d6daf0895c02c62bd54 from qemu
2018-05-15 21:55:42 -04:00
Richard Henderson bcaceb9bc7
target/arm: Implement FMOV (general) for fp16
Adding the fp16 moves to/from general registers.

Backports commit 68130236e30a1ec64363f4915349feee181bfbc1 from qemu
2018-05-15 21:54:32 -04:00
Peter Maydell 2629c0122e
target/arm: Fix fp_status_f16 tininess before rounding
In commit d81ce0ef2c4f105 we added an extra float_status field
fp_status_fp16 for Arm, but forgot to initialize it correctly
by setting it to float_tininess_before_rounding. This currently
will only cause problems for the new V8_FP16 feature, since the
float-to-float conversion code doesn't use it yet. The effect
would be that we failed to set the Underflow IEEE exception flag
in all the cases where we should.

Add the missing initialization.

Backports commit bcc531f0364796104df4443d17f99b5fb494eca2 from qemu
2018-05-15 21:51:48 -04:00
Richard Henderson 5902f32abf
target/arm: Clear SVE high bits for FMOV
Use write_fp_dreg and clear_vec_high to zero the bits
that need zeroing for these cases.

Backports commit 9a9f1f59521f46e8ff4527d9a2b52f83577e2aa3 from qemu
2018-05-14 08:43:55 -04:00
Richard Henderson 67740bbc7f
target/arm: Fix float16 to/from int16
The instruction "ucvtf v0.4h, v04h, #2", with input 0x8000u,
overflows the intermediate float16 to infinity before we have a
chance to scale the output. Use float64 as the intermediate type
so that no input argument (uint32_t in this case) can overflow
or round before scaling. Given the declared argument, the signed
int32_t function has the same problem.

When converting from float16 to integer, using u/int32_t instead
of u/int16_t means that the bounding is incorrect.

Backports commit 88808a022c06f98d81cd3f2d105a5734c5614839 from qemu
2018-05-14 08:41:20 -04:00
Richard Henderson e403957a5e
target/arm: Implement vector shifted FCVT for fp16
While we have some of the scalar paths for FCVT for fp16,
we failed to decode the fp16 version of these instructions.

Backports commit d0ba8e74acd299b092786ffc30b306638d395a9e from qemu
2018-05-14 08:36:54 -04:00
Richard Henderson ad6c191d96
target/arm: Implement vector shifted SCVF/UCVF for fp16
While we have some of the scalar paths for *CVF for fp16,
we failed to decode the fp16 version of these instructions.

Backports commit a6117fae4576edfe7a5a5b802a742c33112c0993 from qemu
2018-05-14 08:31:29 -04:00
Richard Henderson 5752b2086b
target/arm: Enable ARM_FEATURE_V8_ATOMICS for user-only
Backports commit ec7f05fae36637d11de272da82ad1e6c233e77d7 from qemu
2018-05-14 08:29:59 -04:00
Richard Henderson 688d0fd0ed
target/arm: Implement CAS and CASP
Backports commit 44ac14b06fa33f60982923b6b8a3bf8dd2fea61d from qemu
2018-05-14 08:28:45 -04:00
Richard Henderson b23c543e1a
target/arm: Fill in disas_ldst_atomic
This implements all of the v8.1-Atomics instructions except
for compare-and-swap, which is decoded elsewhere.

Backports commit 74608ea45434c9b07055b21885e093528c5ed98c from qemu
2018-05-14 08:18:37 -04:00
Richard Henderson 7ae8671b5e
target/arm: Introduce ARM_FEATURE_V8_ATOMICS and initial decode
The insns in the ARMv8.1-Atomics are added to the existing
load/store exclusive and load/store reg opcode spaces.
Rearrange the top-level decoders for these to accomodate.
The Atomics insns themselves still generate Unallocated.

Backports commit 68412d2ecedbab5a43b0d346cddb27e00d724aff from qemu
2018-05-14 08:15:52 -04:00
Richard Henderson b2af557a0f
target/arm: Use new min/max expanders
The generic expanders replace nearly identical code in the translator.

Backports commit ecb8ab8d71aab770555a6972428b711400a27248 from qemu
2018-05-14 07:34:52 -04:00
Emilio G. Cota d26bf1d446
translator: merge max_insns into DisasContextBase
While at it, use int for both num_insns and max_insns to make
sure we have same-type comparisons.

Backports commit b542683d77b4f56cef0221b267c341616d87bce9 from qemu
2018-05-11 13:59:17 -04:00
Emilio G. Cota 8162e6f1c6
target/arm: avoid integer overflow in next_page PC check
If the PC is in the last page of the address space, next_page_start
overflows to 0. Fix it.

Backports commit bfe7ad5be77a6a8925a7ab1628452c8942222102 from qemu
2018-05-11 13:49:57 -04:00
Peter Maydell ca9b601d0d
target/arm: Implement v8M VLLDM and VLSTM
For v8M the instructions VLLDM and VLSTM support lazy saving
and restoring of the secure floating-point registers. Even
if the floating point extension is not implemented, these
instructions must act as NOPs in Secure state, so they can
be used as part of the secure-to-nonsecure call sequence.

Fixes: https://bugs.launchpad.net/qemu/+bug/1768295

Backports commit b1e5336a9899016c53d59eba53ebf6abcc21995c from qemu
2018-05-08 08:29:12 -04:00
Mathew Maidment 06da6ae3c8
target/arm: Correct MPUIR privilege level in register_cp_regs_for_features() conditional case
The duplication of id_tlbtr_reginfo was unintentionally added within
3281af8114c6b8ead02f08b58e3c36895c1ea047 which should have been
id_mpuir_reginfo.

The effect was that for OMAP and StrongARM CPUs we would
incorrectly UNDEF writes to MPUIR rather than NOPing them.

Backports commit 100061121c1f69a672ce7bb3e9e3781f8018f9f6 from qemu
2018-05-08 08:27:40 -04:00
Richard Henderson 5940a36394
target/arm: Tidy condition in disas_simd_two_reg_misc
Path analysis shows that size == 3 && !is_q has been eliminated.

Fixes: Coverity CID1385853

Backports commit a8766e3172c1671cab297c1ef4566a3c5d094822 from qemu
2018-05-08 08:26:31 -04:00
Richard Henderson cb324fd039
target/arm: Tidy conditions in handle_vec_simd_shri
The (size > 3 && !is_q) condition is identical to the preceeding test
of bit 3 in immh; eliminate it. For the benefit of Coverity, assert
that size is within the bounds we expect.

Fixes: Coverity CID1385846
Fixes: Coverity CID1385849
Fixes: Coverity CID1385852
Fixes: Coverity CID1385857

Backports commit 8dae46970532afcf93470b00e83ca9921980efc3 from qemu
2018-05-08 08:25:37 -04:00
Aaron Lindsay d3e7bbffea
target/arm: Make PMOVSCLR and PMUSERENR 64 bits wide
This is a bug fix to ensure 64-bit reads of these registers don't read
adjacent data.

Backports commit e4e91a217c17fff4045dd4b423cdcb471b3d6a0e from qemu
2018-04-26 09:25:09 -04:00
Aaron Lindsay 4ed7524444
target/arm: Fix bitmask for PMCCFILTR writes
It was shifted to the left one bit too few.

Backports commit ac57fd24cd864d42e7551f82266bc0930bd39547 from qemu
2018-04-26 09:23:04 -04:00
Aaron Lindsay 99a0be89a8
target/arm: Add pre-EL change hooks
Because the design of the PMU requires that the counter values be
converted between their delta and guest-visible forms for mode
filtering, an additional hook which occurs before the EL is changed is
necessary.

Backports commit b5c53d1b3886387874f8c8582b205aeb3e4c3df6 from qemu
2018-04-26 09:21:54 -04:00
Aaron Lindsay 8caf217d26
target/arm: Support multiple EL change hooks
Backports commit 08267487c99e8150382420936ab72c1e0ad74ce3 from qemu
2018-04-26 09:16:09 -04:00
Aaron Lindsay dfe1f54920
target/arm: Fetch GICv3 state directly from CPUARMState
This eliminates the need for fetching it from el_change_hook_opaque, and
allows for supporting multiple el_change_hooks without having to hack
something together to find the registered opaque belonging to GICv3.

Backports commit d5a5e4c93dae0dc3feb402cf7ee78d846da1a7e1 from qemu
2018-04-26 09:10:32 -04:00
Aaron Lindsay 1228bcf45d
target/arm: Mask PMU register writes based on PMCR_EL0.N
This is in preparation for enabling counters other than PMCCNTR

Backports commit 7ece99b17e832065236c07a158dfac62619ef99b from qemu
2018-04-26 09:09:12 -04:00
Aaron Lindsay e1d021ad74
target/arm: Treat PMCCNTR as alias of PMCCNTR_EL0
They share the same underlying state

Backports commit 169c893874977eee8303a6dad4a3f25c5464858f from qemu
2018-04-26 09:07:50 -04:00
Aaron Lindsay e1bffbf7df
target/arm: Check PMCNTEN for whether PMCCNTR is enabled
Backports commit ccbc0e338486b21cb0eb52e52cd309bbbe6a7507 from qemu
2018-04-26 09:07:02 -04:00
Peter Maydell 43e7478d3f
target/arm: Use v7m_stack_read() for reading the frame signature
In commit 95695effe8caa552b8f2 we changed the v7M/v8M stack
pop code to use a new v7m_stack_read() function that checks
whether the read should fail due to an MPU or bus abort.
We missed one call though, the one which reads the signature
word for the callee-saved register part of the frame.

Correct the omission.

Backports commit 4818bad98c8212fbbb0525d10761b6b65279ab92 from qemu
2018-04-26 09:02:11 -04:00
Peter Maydell bec50934ad
target/arm: Remove stale TODO comment
Remove a stale TODO comment -- we have now made the arm_ldl_ptw()
and arm_ldq_ptw() functions propagate physical memory read errors
out to their callers.

Backports commit 145772707fe80395b87c244ccf5699a756f1946b from qemu
2018-04-26 09:00:08 -04:00
Pavel Dovgalyuk b4bf3c776b
icount: fix cpu_restore_state_from_tb for non-tb-exit cases
In icount mode, instructions that access io memory spaces in the middle
of the translation block invoke TB recompilation. After recompilation,
such instructions become last in the TB and are allowed to access io
memory spaces.

When the code includes instruction like i386 'xchg eax, 0xffffd080'
which accesses APIC, QEMU goes into an infinite loop of the recompilation.

This instruction includes two memory accesses - one read and one write.
After the first access, APIC calls cpu_report_tpr_access, which restores
the CPU state to get the current eip. But cpu_restore_state_from_tb
resets the cpu->can_do_io flag which makes the second memory access invalid.
Therefore the second memory access causes a recompilation of the block.
Then these operations repeat again and again.

This patch moves resetting cpu->can_do_io flag from
cpu_restore_state_from_tb to cpu_loop_exit* functions.

It also adds a parameter for cpu_restore_state which controls restoring
icount. There is no need to restore icount when we only query CPU state
without breaking the TB. Restoring it in such cases leads to the
incorrect flow of the virtual time.

In most cases new parameter is true (icount should be recalculated).
But there are two cases in i386 and openrisc when the CPU state is only
queried without the need to break the TB. This patch fixes both of
these cases.

Backports commit afd46fcad2dceffda35c0586f5723c127b6e09d8 from qemu
2018-04-11 20:05:40 -04:00
Richard Henderson 49476ebf5e
tcg: Introduce tcg_set_insn_start_param
The parameters for tcg_gen_insn_start are target_ulong, which may be split
into two TCGArg parameters for storage in the opcode on 32-bit hosts.

Fixes the ARM target and its direct use of tcg_set_insn_param, which would
set the wrong argument in the 64-on-32 case.

Backports commit 9743cd5736263e90d312b2c33bd739ffe1eae70d from qemu
2018-04-11 19:34:18 -04:00
Peter Maydell 8f26d8e556
target/arm: Report unsupported MPU region sizes more clearly
Currently our PMSAv7 and ARMv7M MPU implementation cannot handle
MPU region sizes smaller than our TARGET_PAGE_SIZE. However we
report that in a slightly confusing way:

DRSR[3]: No support for MPU (sub)region alignment of 9 bits. Minimum is 10

The problem is not the alignment of the region, but its size;
tweak the error message to say so:
DRSR[3]: No support for MPU (sub)region size of 512 bytes. Minimum is 1024.

Backports commit 8aec759b45fa6986c0b159cb27353d6abb0d5d73 from qemu
2018-04-11 19:32:16 -04:00
Onur Sahin 18e6b1549f
target-arm: Check undefined opcodes for SWP in A32 decoder
Make sure we are not treating architecturally Undefined instructions
as a SWP, by verifying the opcodes as per section A8.8.229 of ARMv7-A
specification. Bits [21:20] must be zero for this to be a SWP or SWPB.
We also choose to UNDEF for the architecturally UNPREDICTABLE case of
bits [11:8] not being zero.

Backports commit c4869ca630a57f4269bb932ec7f719cef5bc79b8 from qemu
2018-04-11 19:30:50 -04:00
Peter Maydell 92b5817d92
target/arm: Always set FAR to a known unknown value for debug exceptions
For debug exceptions due to breakpoints or the BKPT instruction which
are taken to AArch32, the Fault Address Register is architecturally
UNKNOWN. We were using that as license to simply not set
env->exception.vaddress, but this isn't correct, because it will
expose to the guest whatever old value was in that field when
arm_cpu_do_interrupt_aarch32() writes it to the guest IFSR. That old
value might be a FAR for a previous guest EL2 or secure exception, in
which case we shouldn't show it to an EL1 or non-secure exception
handler. It might also be a non-deterministic value, which is bad
for record-and-replay.

Clear env->exception.vaddress before taking breakpoint debug
exceptions, to avoid this minor information leak.

Backports commit 548f514cf89dd9ab39c0cb4c063097bccf141fdd from qemu
2018-03-25 16:38:14 -04:00
Peter Maydell d6eafe5982
target/arm: Set FSR for BKPT, BRK when raising exception
Now that we have a helper function specifically for the BRK and
BKPT instructions, we can set the exception.fsr there rather
than in arm_cpu_do_interrupt_aarch32(). This allows us to
use our new arm_debug_exception_fsr() helper.

In particular this fixes a bug where we were hardcoding the
short-form IFSR value, which is wrong if the target exception
level has LPAE enabled.

Fixes: https://bugs.launchpad.net/qemu/+bug/1756927

Backports commit 62b94f31d0df75187bb00684fc29e8639eacc0c5 from qemu
2018-03-25 16:36:51 -04:00
Peter Maydell 16c0c2d253
target/arm: Factor out code to calculate FSR for debug exceptions
When a debug exception is taken to AArch32, it appears as a Prefetch
Abort, and the Instruction Fault Status Register (IFSR) must be set.
The IFSR has two possible formats, depending on whether LPAE is in
use. Factor out the code in arm_debug_excp_handler() which picks
an FSR value into its own utility function, update it to use
arm_fi_to_lfsc() and arm_fi_to_sfsc() rather than hard-coded constants,
and use the correct condition to select long or short format.

In particular this fixes a bug where we could select the short
format because we're at EL0 and the EL1 translation regime is
not using LPAE, but then route the debug exception to EL2 because
of MDCR_EL2.TDE and hand EL2 the wrong format FSR.

Backports commit 81621d9ab8a0f07956e67850b15eebf6d6992eec from qemu
2018-03-25 16:35:27 -04:00
Peter Maydell 7a3ee5fd95
target/arm: Honour MDCR_EL2.TDE when routing exceptions due to BKPT/BRK
The MDCR_EL2.TDE bit allows the exception level targeted by debug
exceptions to be set to EL2 for code executing at EL0. We handle
this in the arm_debug_target_el() function, but this is only used for
hardware breakpoint and watchpoint exceptions, not for the exception
generated when the guest executes an AArch32 BKPT or AArch64 BRK
instruction. We don't have enough information for a translate-time
equivalent of arm_debug_target_el(), so instead make BKPT and BRK
call a special purpose helper which can do the routing, rather than
the generic exception_with_syndrome helper.

Backports commit c900a2e62dd6dde11c8f5249b638caad05bb15be from qemu
2018-03-25 16:33:04 -04:00
Victor Kamensky ecd2ecb590
arm/translate-a64: treat DISAS_UPDATE as variant of DISAS_EXIT
In OE project 4.15 linux kernel boot hang was observed under
single cpu aarch64 qemu. Kernel code was in a loop waiting for
vtimer arrival, spinning in TC generated blocks, while interrupt
was pending unprocessed. This happened because when qemu tried to
handle vtimer interrupt target had interrupts disabled, as
result flag indicating TCG exit, cpu->icount_decr.u16.high,
was cleared but arm_cpu_exec_interrupt function did not call
arm_cpu_do_interrupt to process interrupt. Later when target
reenabled interrupts, it happened without exit into main loop, so
following code that waited for result of interrupt execution
run in infinite loop.

To solve the problem instructions that operate on CPU sys state
(i.e enable/disable interrupt), and marked as DISAS_UPDATE,
should be considered as DISAS_EXIT variant, and should be
forced to exit back to main loop so qemu will have a chance
processing pending CPU state updates, including pending
interrupts.

This change brings consistency with how DISAS_UPDATE is treated
in aarch32 case.

Backports commit a75a52d62418dafe462be4fe30485501d1010bb9 from qemu
2018-03-25 16:27:27 -04:00
Bharata B Rao e373c001fa
cpu: Add Error argument to cpu_exec_init()
Add an Error argument to cpu_exec_init() to let users collect the
error. This is in preparation to change the CPU enumeration logic
in cpu_exec_init(). With the new enumeration logic, cpu_exec_init()
can fail if cpu_index values corresponding to max_cpus have already
been handed out.

Since all current callers of cpu_exec_init() are from instance_init,
use error_abort Error argument to abort in case of an error.

Backports commit 5a790cc4b942e651fec7edc597c19b637fad5a76 from qemu
2018-03-21 07:50:33 -04:00
Igor Mammedov cd27da0d88
cpu: get rid of unused cpu_init() defines
cpu_init(cpu_model) were replaced by cpu_create(cpu_type) so
no users are left, remove it.

Backports commit 3f71e724e283233753f1b5b3d6a30948d3084636 from qemu
2018-03-20 14:21:45 -04:00
Igor Mammedov f86355f82c
cpu: add CPU_RESOLVING_TYPE macro
it will be used for providing to cpu name resolving class for
parsing cpu model for system and user emulation code.

Along with change add target to null-machine tests, so
that when switch to CPU_RESOLVING_TYPE happens,
it would ensure that null-machine usecase still works.

Backports commit 0dacec874fa3b3fd34b0d0670fa257efdcbbebd0 from qemu
2018-03-20 11:28:13 -04:00
Eduardo Habkost 074865ff98
cpu: Generify CPU init functions
Backports commits 2994fd96d986578a342f2342501b4ad30f6d0a85,
701e3c78ce45fa630ffc6826c4b9a4218954bc7f, and
d1853231c60d16af78cf4d1608d043614bfbac0b from qemuu
2018-03-20 08:21:51 -04:00
Peter Crosthwaite ce1831bfb4
target-*: Don't redefine cpu_exec()
This function needs to be converted to QOM hook and virtualised for
multi-arch. This rename interferes, as cpu-qom will not have access
to the renaming causing name divergence. This rename doesn't really do
anything anyway so just delete it.

Backports commit 8642c1b81e0418df066a7960a7426d85a923a253 from qemu
2018-03-20 07:02:47 -04:00
Igor Mammedov 15eb359656
numa: move numa_node from CPUState into target specific classes
Move vcpu's associated numa_node field out of generic CPUState
into inherited classes that actually care about cpu<->numa mapping,
i.e: ARMCPU, PowerPCCPU, X86CPU.

Backports relevant parts of commit 15f8b14228b856850df3fa5ba999ad96521f2208 from qemu
2018-03-20 06:46:20 -04:00
Lioncash 750d56421c
translate/arm/vec_helper: Align to qemu formatting 2018-03-12 11:59:14 -04:00
Lioncash bab31a2510
target/arm/cpu and crypto_helper: Correct bad merge and adjust to qemu code style 2018-03-12 11:57:24 -04:00
Lioncash 0751366e5c
target/arm/op_helper: Correct bad merge 2018-03-12 11:42:43 -04:00
Lioncash 9a0632bfcf
target/arm/helper64: Correct bad merge 2018-03-12 11:37:27 -04:00
Lioncash c93c3bd4b3
target/arm/helper: Correct bad merge 2018-03-12 11:33:45 -04:00
Lioncash 14c1fcd5bf
target/arm/translate: Correct bad merge 2018-03-12 11:17:37 -04:00
Lioncash 0dd13de42f
target/arm/translate-a64: Correct bad merge 2018-03-12 11:17:33 -04:00
Peter Maydell fabd6c7ae8
target/arm: Make 'any' CPU just an alias for 'max'
Now we have a working '-cpu max', the linux-user-only
'any' CPU is pretty much the same thing, so implement it
that way.

For the moment we don't add any of the extra feature bits
to the system-emulation "max", because we don't set the
ID register bits we would need to to advertise those
features as present.

Backports commit a0032cc5427d0d396aa0a9383ad9980533448ea4 from qemu
2018-03-12 10:11:49 -04:00
Peter Maydell 7388fff079
target/arm: Add "-cpu max" support
Add support for "-cpu max" for ARM guests. This CPU type behaves
like "-cpu host" when KVM is enabled, and like a system CPU with
the maximum possible feature set otherwise. (Note that this means
it won't be migratable across versions, as we will likely add
features to it in future.)

Backports commit bab52d4bba3f22921a690a887b4bd0342f2754cd from qemu
2018-03-12 10:11:49 -04:00
Alistair Francis 44d8c38138
target/arm: Add a core count property
The cortex A53 TRM specifies that bits 24 and 25 of the L2CTLR register
specify the number of cores in the processor, not the total number of
cores in the system. To report this correctly on machines with multiple
CPU clusters (ARM's big.LITTLE or Xilinx's ZynqMP) we need to allow
the machine to overwrite this value. To do this let's add an optional
property.

Backports commit f9a697112ee64180354f98309a5d6b691cc8699d from qemu
2018-03-12 10:11:48 -04:00
Lioncash 8e161bb723
target/arm: Use the any cpu model instead of cortex-a57
The Cortex-A57 doesn't allow use of v8.1+ architecture instructions
2018-03-12 03:42:57 -04:00
Eduardo Habkost a7f59d7771
Use DEFINE_MACHINE() to register all machines
Convert all machines to use DEFINE_MACHINE() instead of QEMUMachine
automatically using a script.

Backports commit e264d29de28c5b0be3d063307ce9fb613b427cc3 from qemu
2018-03-11 15:12:46 -04:00
Richard Henderson 81ae246f07
target/arm: Enable ARM_FEATURE_V8_FCMA
Enable it for the "any" CPU used by *-linux-user.

Backports commit e66a67bf28e1b4fce2e3d72a2610dbd48d9d3078 from qemu
2018-03-09 01:12:19 -05:00
Richard Henderson 85cfb78ea2
target/arm: Decode t32 simd 3reg and 2reg_scalar extension
Happily, the bits are in the same places compared to a32.

Backports commit 0052087efb8a5c0e29ddc2f59f8476fcdc6495b2 from qemu
2018-03-09 01:11:14 -05:00
Richard Henderson e5da25aaf8
target/arm: Decode aa32 armv8.3 2-reg-index
Backports commit 638808ff8a0c0d62333822d3756e5d98f9f369c3 from qemu
2018-03-09 01:09:59 -05:00
Richard Henderson 69890ae145
target/arm: Decode aa32 armv8.3 3-same
Backports commit 8b7209fae730813d722b17a8a13b6a16c84616c8 from qemu
2018-03-09 01:08:26 -05:00
Richard Henderson abd86b2287
target/arm: Decode aa64 armv8.3 fcmla
Backports commit d17b7cdcf4ea3e858ceee8b86fc8544bb71561e6 from qemu

Also remember to commit vec_helper.
2018-03-09 01:05:02 -05:00
Richard Henderson 4b39a36416
target/arm: Decode aa64 armv8.3 fcadd
Backports commit 1695cd61b08d4376c11e0658836c4f08b4fc3aa1 from qemu
2018-03-09 00:58:37 -05:00
Richard Henderson 0b1ab3e745
target/arm: Add ARM_FEATURE_V8_FCMA
Not enabled anywhere yet.

Backports commit 0438f0372a7031debe796f4e3d30875d4d1e7899 from qemu
2018-03-09 00:28:37 -05:00
Richard Henderson fc74a022bf
target/arm: Enable ARM_FEATURE_V8_RDM
Enable it for the "any" CPU used by *-linux-user.

Backports commit f5dfc2ecdd48b71900bc50298ad2768d60356e44 from qemu
2018-03-09 00:27:34 -05:00
Richard Henderson 78b0b9c523
target/arm: Decode aa32 armv8.1 two reg and a scalar
Backports commit 61adacc8f589539ac6b25cfcbd6e099357188974 from qemu
2018-03-09 00:24:14 -05:00
Richard Henderson ca4ceb2dd7
target/arm: Decode aa32 armv8.1 three same
Backports commit 36a719348a9744d17c6ef6bac01bcb5fcd279753 from qemu
2018-03-09 00:18:31 -05:00
Richard Henderson 152c9484bd
target/arm: Decode aa64 armv8.1 scalar/vector x indexed element
Backports commit d345df7a3f1336ceb0537c1fa0a7261030426768 from qemu
2018-03-09 00:12:00 -05:00
Lioncash 12fd2cc113
target/arm: Decode aa64 armv8.1 three same extra 2018-03-09 00:10:09 -05:00
Richard Henderson 4f585f71fb
target/arm: Decode aa64 armv8.1 scalar three same extra
Backports commit d9061ec3d27eb940402a7eafee3fb77ce1146ad4 from qemu
2018-03-09 00:02:23 -05:00
Richard Henderson 774cbded7a
target/arm: Refactor disas_simd_indexed size checks
The integer size check was already outside of the opcode switch;
move the floating-point size check outside as well. Unify the
size vs index adjustment between fp and integer paths.

Backports commit 449f264b1749ac0e59c58bbc2eacdb3dc302c2bf from qemu
2018-03-08 23:53:39 -05:00
Richard Henderson 1fd2644738
target/arm: Refactor disas_simd_indexed decode
Include the U bit in the switches rather than testing separately.

Backports commit 5f81b1de43259ed0969e62a7419ab9dd9da2c5c0 from qemu
2018-03-08 23:44:03 -05:00
Richard Henderson 109a777fd6
target/arm: Add ARM_FEATURE_V8_RDM
Not enabled anywhere yet.

Backports commit 1dc81c15418d9b174f59a1c6262eb3487f352c56 from qemu
2018-03-08 23:44:03 -05:00
Peter Maydell e917a1ac0e
target/arm: Add Cortex-M33
Add a Cortex-M33 definition. The M33 is an M profile CPU
which implements the ARM v8M architecture, including the
M profile Security Extension.

Backports commit c7b26382fee8b745c6e903c85281babf30c2cb7c from qemu
2018-03-08 23:44:03 -05:00
Peter Maydell bd606401dc
target/arm: Define init-svtor property for the reset secure VTOR value
The Cortex-M33 allows the system to specify the reset value of the
secure Vector Table Offset Register (VTOR) by asserting config
signals. In particular, guest images for the MPS2 AN505 board rely
on the MPS2's initial VTOR being correct for that board.
Implement a QEMU property so board and SoC code can set the reset
value to the correct value.

Backports commit 38e2a77c9d6876e58f45cabb1dd9a6a60c22b39e from qemu
2018-03-08 23:44:03 -05:00
Peter Maydell eb4796e965
target/arm: Enable ARM_V8_FP16 feature bit for the AArch64 any CPU
Now we have implemented FP16 we can enable it for the "any" CPU.

Backports commit 969b389ee8ba84bc3f2e7ccfa993679fac410ad2 from qemu
2018-03-08 23:44:02 -05:00
Alex Bennée 6e41113897
arm/translate-a64: add all single op FP16 to handle_fp_1src_half
This includes FMOV, FABS, FNEG, FSQRT and FRINT[NPMZAXI]. We re-use
existing helpers to achieve this.

Backports commit c2c08713a6a5846bbe601d4d1b4f9708ba77efdc from qemu
2018-03-08 23:44:02 -05:00
Alex Bennée c6c8a1cccc
arm/translate-a64: implement simd_scalar_three_reg_same_fp16
This covers the encoding group:

Advanced SIMD scalar three same FP16

As all the helpers are already there it is simply a case of calling the
existing helpers in the scalar context.

Backports commit 7c93b7741b29b3ffda81a6e9525771b4409db99f from qemu
2018-03-08 23:44:02 -05:00
Alex Bennée dd29452046
arm/translate-a64: add all FP16 ops in simd_scalar_pairwise
I only needed to do a little light re-factoring to support the
half-precision helpers.

Backports commit 5c36d89567cfd049a7c59ff219639f788225068f from qemu
2018-03-08 23:44:02 -05:00
Alex Bennée 8bbabd7eb3
arm/translate-a64: add FP16 FMOV to simd_mod_imm
Only one half-precision instruction has been added to this group.

Backports commit 70b4e6a445715519ae55179dc54f6e961ab30c27 from qemu
2018-03-08 23:43:52 -05:00
Alex Bennée b117df18df
arm/translate-a64: add FP16 FRSQRTE to simd_two_reg_misc_fp16
Backports commit c625ff95070e3ef96bd007de744e1d97c881efeb from qemu
2018-03-08 22:45:39 -05:00
Alex Bennée 068143595e
arm/helper.c: re-factor rsqrte and add rsqrte_f16
Much like recpe the ARM ARM has simplified the pseudo code for the
calculation which is done on a fixed point 9 bit integer maths. So
while adding f16 we can also clean this up to be a little less heavy
on the floating point and just return the fractional part and leave
the calle's to do the final packing of the result.

Backports commit d719cbc7641991d16b891ffbbfc3a16a04e37b9a from qemu

Also removes a load of symbols that seem unnecessary from the header_gen script
2018-03-08 22:42:04 -05:00
Alex Bennée fdb07713e6
arm/translate-a64: add FP16 FSQRT to simd_two_reg_misc_fp16
Backports commit b96a54c7e5576bd35b7d00d37b7929d2892d8cac from qemu
2018-03-08 21:57:35 -05:00
Alex Bennée 6102a61b14
arm/translate-a64: add FP16 FRCPX to simd_two_reg_misc_fp16
We go with the localised helper.

Backports commit 986950283837f697b35782b9ac3bc99fca614640 from qemu
2018-03-08 19:15:23 -05:00
Alex Bennée 4ea310c131
arm/translate-a64: add FP16 FRECPE
Now we have added f16 during the re-factoring we can simply call the
helper.

Backports commit fbd06e1e4b6566b4d727f9e553c819d034942f68 from qemu
2018-03-08 19:12:06 -05:00
Alex Bennée 5f3864c2c2
arm/helper.c: re-factor recpe and add recepe_f16
It looks like the ARM ARM has simplified the pseudo code for the
calculation which is done on a fixed point 9 bit integer maths. So
while adding f16 we can also clean this up to be a little less heavy
on the floating point and just return the fractional part and leave
the calle's to do the final packing of the result.

Backports commit 5eb70735af1c0b607bf2671a53aff3710cc1672f from qemu
2018-03-08 19:05:48 -05:00
Alex Bennée c590ff441c
arm/translate-a64: add FP16 FNEG/FABS to simd_two_reg_misc_fp16
Neither of these operations alter the floating point status registers
so we can do a pure bitwise operation, either squashing any sign
bit (ABS) or inverting it (NEG).

Backports commit 15f8a233c8c023dbc77b6fe6cd7c79eac9bee263 from qemu
2018-03-08 18:51:35 -05:00
Alex Bennée 7161c1ed52
arm/translate-a64: add FP16 SCVTF/UCVFT to simd_two_reg_misc_fp16 2018-03-08 18:48:25 -05:00
Alex Bennée 8ac9e3cff2
arm/translate-a64: add FP16 FCMxx (zero) to simd_two_reg_misc_fp16
I re-use the existing handle_2misc_fcmp_zero handler and tweak it
slightly to deal with the half-precision case.

Backports commit 7d4dd1a73a023f75c893623710e43743501b318e from qemu
2018-03-08 18:32:36 -05:00
Alex Bennée 39a68548d1
arm/translate-a64: add FCVTxx to simd_two_reg_misc_fp16
This covers all the floating point convert operations.

Backports commit 2df581304193d70eaf0d22cf4cb4613f74b6e59b from qemu
2018-03-08 18:25:29 -05:00
Alex Bennée d5f002b39a
arm/translate-a64: add FP16 FPRINTx to simd_two_reg_misc_fp16
This adds the full range of half-precision floating point to integral
instructions.

Backports commit 6109aea2d954891027acba64a13f1f1c7463cfac from qemu
2018-03-08 18:21:58 -05:00
Alex Bennée 33eda0f5d4
arm/translate-a64: initial decode for simd_two_reg_misc_fp16
This actually covers two different sections of the encoding table:

Advanced SIMD scalar two-register miscellaneous FP16
Advanced SIMD two-register miscellaneous (FP16)

The difference between the two is covered by a combination of Q (bit
30) and S (bit 28). Notably the FRINTx instructions are only
available in the vector form.

This is just the decode skeleton which will be filled out by later
patches.

Backports commit 5d432be6fd6efe37833ac82623c3abd35117b421 from qemu
2018-03-08 18:14:04 -05:00
Alex Bennée 82ffaab7de
arm/translate-a64: add FP16 x2 ops for simd_indexed
A bunch of the vectorised bitwise operations just operate on larger
chunks at a time. We can do the same for the new half-precision
operations by introducing some TWOHALFOP helpers which work on each
half of a pair of half-precision operations at once.

Hopefully all this hoop jumping will get simpler once we have
generically vectorised helpers here.

Backports commit 6089030c7322d8f96b54fb9904e53b0f464bb8fe from qemu
2018-03-08 18:08:39 -05:00
Alex Bennée 38815b2901
arm/translate-a64: add FP16 FMULX/MLS/FMLA to simd_indexed
The helpers use the new re-factored muladd support in SoftFloat for
the float16 work.

Backports commit 5d265064cf30daaacce5a4ce9945fc573015fb5f from qemu
2018-03-08 15:56:20 -05:00
Alex Bennée c6fda07628
arm/translate-a64: add FP16 pairwise ops simd_three_reg_same_fp16
This includes FMAXNMP, FADDP, FMAXP, FMINNMP, FMINP.

Backports commit 7a2c6e618156674cf9eac8bf36e79f674fbf974e from qemu
2018-03-08 15:50:56 -05:00
Alex Bennée 4b2577537b
arm/translate-a64: add FP16 FR[ECP/SQRT]S to simd_three_reg_same_fp16
As some of the constants here will also be needed
elsewhere (specifically for the upcoming SVE support) we move them out
to softfloat.h.

Backports commit 026e2d6ef74000afb9049f46add4b94f594c8fb3 from qemu
2018-03-08 15:47:34 -05:00
Alex Bennée a02b9b81a9
arm/translate-a64: add FP16 FMULA/X/S to simd_three_reg_same_fp16
Backports commit 2deb992b767d28035fac3b374c7730494ff0b43d from qemu

Also backports the fp16 changes introduced in commit f566c0474a9b9bbd9ed248607e4007e24d3358c0
2018-03-08 15:42:48 -05:00
Alex Bennée ba8df54753
arm/translate-a64: add FP16 F[A]C[EQ/GE/GT] to simd_three_reg_same_fp16
These use the generic float16_compare functionality which in turn uses
the common float_compare code from the softfloat re-factor.

Backports commit d32adeae1a71a8e71374fa48d3d6ab0ad4c23e94 from qemu
2018-03-08 12:59:37 -05:00
Alex Bennée 4a6a41d2c5
arm/translate-a64: add FP16 FADD/FABD/FSUB/FMUL/FDIV to simd_three_reg_same_fp16
The fprintf is only there for debugging as the skeleton is added to,
it will be removed once the skeleton is complete.

Backports commit 372087348d561e7f4051d7b32609bda417092ddf from qemu
2018-03-08 12:56:15 -05:00
Alex Bennée 2f850606e9
arm/translate-a64: initial decode for simd_three_reg_same_fp16
This is the initial decode skeleton for the Advanced SIMD three same
instruction group.

The fprintf is purely to aid debugging as the additional instructions
are added. It will be removed once the group is complete.

Backports commit 376e8d6cda985df31c8561db4b7ea365b6fe6f87 from qemu
2018-03-08 12:53:23 -05:00
Alex Bennée fe74abd307
arm/translate-a64: handle_3same_64 comment fix
We do implement all the opcodes.

Backports commit 3840d219b433507f04a685120ff770ce4e06c55d from qemu
2018-03-08 12:51:01 -05:00
Alex Bennée af75074fe7
arm/translate-a64: implement half-precision F(MIN|MAX)(V|NMV)
This implements the half-precision variants of the across vector
reduction operations. This involves a re-factor of the reduction code
which more closely matches the ARM ARM order (and handles 8 element
reductions).

Backports commit 807cdd504283c11addcd7ea95ba594bbddc86fe4 from qemu
2018-03-08 12:49:30 -05:00
Alex Bennée 27d8d01566
target/arm/helper: pass explicit fpst to set_rmode
As the rounding mode is now split between FP16 and the rest of
floating point we need to be explicit when tweaking it. Instead of
passing the CPU env we now pass the appropriate fpst pointer directly.

Backports commit 9b04991686785e18b18a36d193b68f08f7c91648 from qemu
2018-03-08 12:41:54 -05:00
Alex Bennée 996f38056f
target/arm/cpu.h: add additional float_status flags
Half-precision flush to zero behaviour is controlled by a separate
FZ16 bit in the FPCR. To handle this we pass a pointer to
fp_status_fp16 when working on half-precision operations. The value of
the presented FPCR is calculated from an amalgam of the two when read.

Backports commit d81ce0ef2c4f1052fcdef891a12499eca3084db7 from qemu
2018-03-08 12:34:39 -05:00
Alex Bennée 348789d2e4
target/arm/cpu.h: update comment for half-precision values
Backports commit d0e69ea88f4e74212b29d9436143c5bcfd437757 from qemu
2018-03-08 12:29:47 -05:00
Alex Bennée a030564492
target/arm/cpu64: introduce ARM_V8_FP16 feature bit
Backports commit 6ad4d6187563f069fe5f11c3c1c9ccec1f69c2b7 from qemu
2018-03-08 12:29:17 -05:00
Peter Maydell f4df29ca4f
target/arm: Fix register definitions for VMIDR and VMPIDR
The register definitions for VMIDR and VMPIDR have separate
reginfo structs for the AArch32 and AArch64 registers. However
the 32-bit versions are wrong:
* they use offsetof instead of offsetoflow32 to mark where
the 32-bit value lives in the uint64_t CPU state field
* they don't mark themselves as ARM_CP_ALIAS

In particular this means that if you try to use an Arm guest CPU
which enables EL2 on a big-endian host it will assert at reset:
target/arm/cpu.c:114: cp_reg_check_reset: Assertion `oldvalue == newvalue' failed.

because the reset of the 32-bit register writes to the top
half of the uint64_t.

Correct the errors in the structures.

Backports commit 36476562d57a3b64bbe86db26e63677dd21907c5 from qemu
2018-03-08 12:26:09 -05:00
Alex Bennée 0eee5afd0e
target/*/cpu.h: remove softfloat.h
As cpu.h is another typically widely included file which doesn't need
full access to the softfloat API we can remove the includes from here
as well. Where they do need types it's typically for float_status and
the rounding modes so we move that to softfloat-types.h as well.

As a result of not having softfloat in every cpu.h call we now need to
add it to various helpers that do need the full softfloat.h
definitions.

Backports commit 24f91e81b65fcdd0552d1f0fcb0ea7cfe3829c19 from qemu
2018-03-08 09:58:47 -05:00
Peter Maydell 19baeb5120
target/arm: Implement v8M MSPLIM and PSPLIM registers
The v8M architecture includes hardware support for enforcing
stack pointer limits. We don't implement this behaviour yet,
but provide the MSPLIM and PSPLIM stack pointer limit registers
as reads-as-written, so that when we do implement the checks
in future this won't break guest migration.

Backports commit 57bb31568114023f67680d6fe478ceb13c51aa7d from qemu
2018-03-08 09:42:04 -05:00
Peter Maydell 5812f7e3a3
target/arm: Implement writing to CONTROL_NS for v8M
In commit 50f11062d4c896 we added support for MSR/MRS access
to the NS banked special registers, but we forgot to implement
the support for writing to CONTROL_NS. Correct the omission.

Backports commit 6eb3a64e2a96f5ced1f7896042b01f002bf0a91f from qemu
2018-03-08 09:39:43 -05:00
Peter Maydell 09cfe29d5b
hw/intc/armv7m_nvic: Implement SCR
We were previously making the system control register (SCR)
just RAZ/WI. Although we don't implement the functionality
this register controls, we should at least provide the state,
including the banked state for v8M.

Backports register related changes in commit 24ac0fb129f9ce9dd96901b2377fc6271dc55b2b from qemu
2018-03-08 09:36:59 -05:00
Peter Maydell c390c07ae0
hw/intc/armv7m_nvic: Implement cache ID registers
M profile cores have a similar setup for cache ID registers
to A profile:
* Cache Level ID Register (CLIDR) is a fixed value
* Cache Type Register (CTR) is a fixed value
* Cache Size ID Registers (CCSIDR) are a bank of registers;
which one you see is selected by the Cache Size Selection
Register (CSSELR)

The only difference is that they're in the NVIC memory mapped
register space rather than being coprocessor registers.
Implement the M profile view of them.

Since neither Cortex-M3 nor Cortex-M4 implement caches,
we don't need to update their init functions and can leave
the ctr/clidr/ccsidr[] fields in their ARMCPU structs at zero.
Newer cores (like the Cortex-M33) will want to be able to
set these ID registers to non-zero values, though.

Backports commit 43bbce7fbef22adf687dd84934fd0b2f8df807a8 from qemu
2018-03-08 09:35:53 -05:00
Peter Maydell 6f31c219b9
hw/intc/armv7m_nvic: Don't hardcode M profile ID registers in NVIC
Instead of hardcoding the values of M profile ID registers in the
NVIC, use the fields in the CPU struct. This will allow us to
give different M profile CPU types different ID register values.

This commit includes the addition of the missing ID_ISAR5,
which exists as RES0 in both v7M and v8M.

(The values of the ID registers might be wrong for the M4 --
this commit leaves the behaviour there unchanged.)

Backports commit 5a53e2c1dc939fea1af92cc126ee546d8211d412 from qemu
2018-03-08 09:34:37 -05:00
Richard Henderson 1f71084740
target/arm: Handle SVE registers when using clear_vec_high
When storing to an AdvSIMD FP register, all of the high
bits of the SVE register are zeroed. Therefore, call it
more often with is_q as a parameter.

Backports commit 4ff55bcb0ee6452b768835f86d94bd727185f812 from qemu
2018-03-08 09:32:33 -05:00
Richard Henderson 07b928eca4
target/arm: Enforce access to ZCR_EL at translation
This also makes sure that we get the correct ordering of
SVE vs FP exceptions.

Backports commit 490aa7f13a2ad31f92205879c4dc2387b602ef14 from qemu
2018-03-08 09:17:33 -05:00
Richard Henderson c095dc9e83
target/arm: Suppress TB end for FPCR/FPSR
Nothing in either register affects the TB.

Backports commit b916c9c35ce8158bf7f9ed5514eb279e52875de2 from qemu
2018-03-08 09:15:02 -05:00
Richard Henderson d5c4d3e3c3
target/arm: Enforce FP access to FPCR/FPSR
Backports commit fe03d45f9e9baa89e8c4da50de771767d5d48990 from qemu
2018-03-08 09:14:52 -05:00
Richard Henderson 1bff556dbc
target/arm: Remove ARM_CP_64BIT from ZCR_EL registers
Because they are ARM_CP_STATE_AA64, ARM_CP_64BIT is implied.

Backports commit 5d1e699988cdb1494ab4ac9a2b67d4c539143654 from qemu
2018-03-08 09:06:46 -05:00
Peter Maydell 8e7ecd89a4
target/arm/translate.c: Fix missing 'break' for TT insns
The code where we added the TT instruction was accidentally
missing a 'break', which meant that after generating the code
to execute the TT we would fall through to 'goto illegal_op'
and generate code to take an UNDEF insn.

Backports commit 384c6c03fb687bea239a5990a538c4bc50fdcecb from qemu
2018-03-07 11:45:39 -05:00
Richard Henderson 02516c53ff
target/arm: Add SVE state to TB->FLAGS
Add both SVE exception state and vector length.

Backports commit 1db5e96c54d8b3d1df0a6fed6771390be6b010da from qemu
2018-03-07 11:44:32 -05:00
Richard Henderson 523e5114c0
target/arm: Add ZCR_ELx
Define ZCR_EL[1-3].

Backports commit 5be5e8eda78474f6e89a54af12ee6f44234115ed from qemu
2018-03-07 11:41:46 -05:00
Richard Henderson a47fb718bc
target/arm: Add predicate registers for SVE
Backports commit 3c7d30866fd1f56e5945726221410e0d8d535033 from qemu
2018-03-07 11:34:57 -05:00
Richard Henderson 834e3a1d04
target/arm: Expand vector registers for SVE
Change vfp.regs as a uint64_t to vfp.zregs as an ARMVectorReg.
The previous patches have made the change in representation
relatively painless.

Backports commit c39c2b9043ec59516c80f2c6f3e8193e99d04d4b from qemu
2018-03-07 11:33:49 -05:00
Lioncash 5439b4a542
unicorn/aarch64: Use qemu-provided helpers for accessing VFP/NEON/SIMD registers
Avoids directly touching the representation of the VFP/NEON/SIMD registers
2018-03-07 11:25:41 -05:00
Lioncash 441f3b73da
unicorn_arm: Use ARM_CPU macro instead of a direct cast in arm_release
Makes the code more reliant on qemu instead of manually doing our own thing
2018-03-07 10:24:21 -05:00
Lioncash 767dedcb09
unicorn_aarch64: Clean up variable assignments in arm64_release 2018-03-07 10:22:51 -05:00
Lioncash d0abc23e99
unicorn/arm: use uc->cpu instead of uc->current_cpu
Keeps cpu variable usage consistent. Also eliminates unnecessary casts
2018-03-07 10:15:49 -05:00
Lioncash 890f234a53
unicorn/aarch64: Lessen the amount of ARMCPU macro usages
This macro can just be used once per function that it's used in,
reducing the overall amount of line noise in register reading and writing
2018-03-07 09:59:27 -05:00
Ard Biesheuvel f425b6aa81
target/arm: enable user-mode SHA-3, SM3, SM4 and SHA-512 instruction support
Add support for the new ARMv8.2 SHA-3, SM3, SM4 and SHA-512 instructions to
AArch64 user mode emulation.

Backports commit 955f56d44a73d74016b2e71765d984ac7a6db1dc from qemu
2018-03-07 08:58:43 -05:00
Ard Biesheuvel 85e6d710e4
target/arm: implement SM4 instructions
This implements emulation of the new SM4 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.

Backports commit b6577bcd251ca0d57ae1de149e3c706b38f21587 from qemu
2018-03-07 08:57:53 -05:00
Ard Biesheuvel 78d15a9cd0
target/arm: implement SM3 instructions
This implements emulation of the new SM3 instructions that have
been added as an optional extension to the ARMv8 Crypto Extensions
in ARM v8.2.

Backports commit 80d6f4c6bbb718f343a832df8dee15329cc7686c from qemu
2018-03-07 08:53:47 -05:00
Ard Biesheuvel 72078a7674
target/arm: implement SHA-3 instructions
This implements emulation of the new SHA-3 instructions that have
been added as an optional extensions to the ARMv8 Crypto Extensions
in ARM v8.2.

Backports commit cd270ade74ea86467f393a9fb9c54c4f1148c28f from qemu
2018-03-07 08:44:47 -05:00
Ard Biesheuvel 66b8b01f09
target/arm: implement SHA-3 instructions
This implements emulation of the new SHA-3 instructions that have
been added as an optional extensions to the ARMv8 Crypto Extensions
in ARM v8.2.

Backports commit cd270ade74ea86467f393a9fb9c54c4f1148c28f from qemu
2018-03-07 08:41:40 -05:00
Ard Biesheuvel 0ef74f6d6d
target/arm: implement SHA-512 instructions
This implements emulation of the new SHA-512 instructions that have
been added as an optional extensions to the ARMv8 Crypto Extensions
in ARM v8.2.

Backports commit 90b827d131812d7f0a8abb13dba1942a2bcee821 from qemu
2018-03-07 08:39:49 -05:00
Peter Maydell c1f778a438
target/arm: Handle exceptions during exception stack pop
Handle possible MPU faults, SAU faults or bus errors when
popping register state off the stack during exception return.

Backports commit 95695effe8caa552b8f243bceb3a08de4003c882 from qemu
2018-03-07 08:33:21 -05:00
Peter Maydell 0dadc2575f
target/arm: Make exception vector loads honour the SAU
Make the load of the exception vector from the vector table honour
the SAU and any bus error on the load (possibly provoking a derived
exception), rather than simply aborting if the load fails.

Backports commit 600c33f24752a00e81e9372261e35c2befea612b from qemu
2018-03-07 08:31:57 -05:00
Peter Maydell 2c8a0fe0d7
nvic: Implement AIRCR changes for v8M
The Application Interrupt and Reset Control Register has some changes
for v8M:
 * new bits SYSRESETREQS, BFHFNMINS and PRIS: these all have
   real state if the security extension is implemented and otherwise
   are constant
 * the PRIGROUP field is banked between security states
 * non-secure code can be blocked from using the SYSRESET bit
   to reset the system if SYSRESETREQS is set

Implement the new state and the changes to register read and write.
For the moment we ignore the effects of the secure PRIGROUP.
We will implement the effects of PRIS and BFHFNMIS later.

Backports register-related additions in commit 3b2e934463121f06d04e4d17658a9a7cdc3717b0 from qemu
2018-03-07 08:30:34 -05:00
Peter Maydell 630a38cf94
target/arm: Make v7m_push_callee_stack() honour MPU
Make v7m_push_callee_stack() honour the MPU by using the
new v7m_stack_write() function. We return a flag to indicate
whether the pushes failed, which we can then use in
v7m_exception_taken() to cause us to handle the derived
exception correctly.

Backports commit 65b4234ff73a4d4865438ce30bdfaaa499464efa from qemu
2018-03-07 08:23:04 -05:00
Peter Maydell 0bc82ea78f
target/arm: Make v7M exception entry stack push check MPU
The memory writes done to push registers on the stack
on exception entry in M profile CPUs are supposed to
go via MPU permissions checks, which may cause us to
take a derived exception instead of the original one of
the MPU lookup fails. We were implementing these as
always-succeeds direct writes to physical memory.
Rewrite v7m_push_stack() to do the necessary checks.

Backports commit fd592d890ec40e3686760de84044230a8ebb1eb3 from qemu
2018-03-07 08:20:02 -05:00
Peter Maydell a10b65bd47
target/arm: Add ignore_stackfaults argument to v7m_exception_taken()
In the v8M architecture, if the process of taking an exception
results in a further exception this is called a derived exception
(for example, an MPU exception when writing the exception frame to
memory). If the derived exception happens while pushing the initial
stack frame, we must ignore any subsequent possible exception
pushing the callee-saves registers.

In preparation for making the stack writes check for exceptions,
add a return value from v7m_push_stack() and a new parameter to
v7m_exception_taken(), so that the former can tell the latter that
it needs to ignore failures to write to the stack. We also plumb
the argument through to v7m_push_callee_stack(), which is where
the code to ignore the failures will be.

(Note that the v8M ARM pseudocode structures this slightly differently:
derived exceptions cause the attempt to process the original
exception to be abandoned; then at the top level it calls
DerivedLateArrival to prioritize the derived exception and call
TakeException from there. We choose to let the NVIC do the prioritization
and continue forward with a call to TakeException which will then
take either the original or the derived exception. The effect is
the same, but this structure works better for QEMU because we don't
have a convenient top level place to do the abandon-and-retry logic.)

Backports commit 0094ca70e165cfb69882fa2e100d935d45f1c983 from qemu
2018-03-07 08:17:25 -05:00
Peter Maydell e1349f817a
target/arm: Split "get pending exception info" from "acknowledge it"
Currently armv7m_nvic_acknowledge_irq() does three things:
* make the current highest priority pending interrupt active
* return a bool indicating whether that interrupt is targeting
Secure or NonSecure state
* implicitly tell the caller which is the highest priority
pending interrupt by setting env->v7m.exception

We need to split these jobs, because v7m_exception_taken()
needs to know whether the pending interrupt targets Secure so
it can choose to stack callee-saves registers or not, but it
must not make the interrupt active until after it has done
that stacking, in case the stacking causes a derived exception.
Similarly, it needs to know the number of the pending interrupt
so it can read the correct vector table entry before the
interrupt is made active, because vector table reads might
also cause a derived exception.

Create a new armv7m_nvic_get_pending_irq_info() function which simply
returns information about the highest priority pending interrupt, and
use it to rearrange the v7m_exception_taken() code so we don't
acknowledge the exception until we've done all the things which could
possibly cause a derived exception.

Backports part of commit 6c9485188170e11ad31ce477c8ce200b8e8ce59d from qemu
2018-03-07 08:12:35 -05:00
Peter Maydell 49010633f0
target/arm: Add armv7m_nvic_set_pending_derived()
In order to support derived exceptions (exceptions generated in
the course of trying to take an exception), we need to be able
to handle prioritizing whether to take the original exception
or the derived exception.

We do this by introducing a new function
armv7m_nvic_set_pending_derived() which the exception-taking code in
helper.c will call when a derived exception occurs. Derived
exceptions are dealt with mostly like normal pending exceptions, so
we share the implementation with the armv7m_nvic_set_pending()
function.

Note that the way we structure this is significantly different
from the v8M Arm ARM pseudocode: that does all the prioritization
logic in the DerivedLateArrival() function, whereas we choose to
let the existing "identify highest priority exception" logic
do the prioritization for us. The effect is the same, though.

Backports part of commit 5ede82b8ccb652382c106d53f656ed67997d76e8 from qemu
2018-03-07 08:10:01 -05:00
Richard Henderson 16a0a3e156
target/arm: Use vector infrastructure for aa64 orr/bic immediate
Backports commit 064e265d5680e5c605d6ee8370fc1e8da094e66d from qemu
2018-03-06 16:17:42 -05:00
Richard Henderson c5c8488928
target/arm: Use vector infrastructure for aa64 multiplies
Backports commit 0c7c55c492c918b6275baa3fee8b176c31465e3c from qemu
2018-03-06 16:14:47 -05:00
Richard Henderson 955fec9300
target/arm: Use vector infrastructure for aa64 compares
Backports commit 79d61de6bdc3980f0efef85f7539e129ab8a4a40 from qemu
2018-03-06 16:10:10 -05:00
Richard Henderson 5626cb714e
target/arm: Use vector infrastructure for aa64 constant shifts
Backports commit cdb45a6063feb5efbb5896795e791dd3db006fbb from qemu
2018-03-06 16:10:10 -05:00
Richard Henderson a63be5a7aa
target/arm: Use vector infrastructure for aa64 dup/movi
Backports commit 861a1ded24917843b9a5a99ea0a6b37c2c9a1930 from qemu
2018-03-06 16:10:10 -05:00
Richard Henderson 84f848d876
target/arm: Use vector infrastructure for aa64 mov/not/neg
Backports commit 377ef731a85773788ae328e638698d27691bd77d from qemu
2018-03-06 16:10:10 -05:00
Richard Henderson 03b76589b4
target/arm: Use vector infrastructure for aa64 add/sub/logic
Backports commit bc48092f5865c20893bb19200a7a320feac99eeb from qemu
2018-03-06 16:10:10 -05:00
Richard Henderson f30abaea66
target/arm: Align vector registers
Backports commit 8b3495ea195503922c1e00253495cb6887b99dd5 from qemu
2018-03-06 16:10:10 -05:00
Laurent Vivier 0aecb15f3b
accel/tcg: add size paremeter in tlb_fill()
The MC68040 MMU provides the size of the access that
triggers the page fault.

This size is set in the Special Status Word which
is written in the stack frame of the access fault
exception.

So we need the size in m68k_cpu_unassigned_access() and
m68k_cpu_handle_mmu_fault().

To be able to do that, this patch modifies the prototype of
handle_mmu_fault handler, tlb_fill() and probe_write().
do_unassigned_access() already includes a size parameter.

This patch also updates handle_mmu_fault handlers and
tlb_fill() of all targets (only parameter, no code change).

Backports commit 98670d47cd8d63a529ff230fd39ddaa186156f8c from qemu
2018-03-06 10:56:34 -05:00
Richard Henderson 0af3b16b5b
target/arm: Simplify fp_exception_el for user-only
Backports commit 55faa21273151259de38da271c8a2f2b37d6c250 from qemu
2018-03-06 10:37:30 -05:00
Richard Henderson 11688c4b12
target/arm: Hoist store to flags output in cpu_get_tb_cpu_state
Backports commit b9adaa70a0dfce7a8e4bdb27a7c6bec5c6f633c4 from qemu
2018-03-06 10:36:51 -05:00
Richard Henderson 7dfbe4e104
target/arm: Move cpu_get_tb_cpu_state out of line
Backports commit a9e013112f03bf1644a549a769be599a3ceb6155 from qemu
2018-03-06 10:33:49 -05:00
Richard Henderson 404fa33c4b
target/arm: Use pointers in neon tbl helper
Rather than passing a regno to the helper, pass pointers to the
vector register directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Backports commit e7c06c4e4c98c47899417f154df1f2ef4e8d09a0 from qemu
2018-03-06 10:20:21 -05:00
Richard Henderson 0bc07dd6be
target/arm: Use pointers in neon zip/uzp helpers
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Backports commit b13708bbbdda54c7f7e28222b22453986c026391 from qemu
2018-03-06 10:17:51 -05:00
Richard Henderson b0578edcf7
target/arm: Use pointers in crypto helpers
Rather than passing regnos to the helpers, pass pointers to the
vector registers directly. This eliminates the need to pass in
the environment pointer and reduces the number of places that
directly access env->vfp.regs[].

Backports commit 1a66ac61af45af04688d1d15896737310e366c06 from qemu
2018-03-06 10:10:06 -05:00
Richard Henderson ca9a411074
target/arm: Mark disas_set_insn_syndrome inline
If it isn't used when translate.h is included,
we'll get a compiler Werror.

Backports commit cf96a682481bbfb1e6b53d2436c3d51563d5dff8 from qemu
2018-03-06 09:20:04 -05:00
Ard Biesheuvel aeee985cc9
target/arm: Fix 32-bit address truncation
Commit ("3b39d734141a target/arm: Handle page table walk load failures
correctly") modified both versions of the page table walking code (i.e.,
arm_ldl_ptw and arm_ldq_ptw) to record the result of the translation in
a temporary 'data' variable so that it can be inspected before being
returned. However, arm_ldq_ptw() returns an uint64_t, and using a
temporary uint32_t variable truncates the upper bits, corrupting the
result. This causes problems when using more than 4 GB of memory in
a TCG guest. So use a uint64_t instead.

Backports commit 9aea1ea31af25fe344a88da086ff913cca09c667 from qemu
2018-03-06 09:19:19 -05:00
Peter Maydell b658f1f36c
target/arm: Handle page table walk load failures correctly
Instead of ignoring the response from address_space_ld*()
(indicating an attempt to read a page table descriptor from
an invalid physical address), use it to report the failure
correctly.

Since this is another couple of locations where we need to
decide the value of the ARMMMUFaultInfo ea bit based on a
MemTxResult, we factor out that operation into a helper
function.

Backports commit 3b39d734141a71296d08af3d4c32f872fafd782e from qemu
2018-03-06 08:55:08 -05:00
Peter Maydell fe9271d5bd
get_phys_addr_pmsav7: Support AP=0b111 for v7M
For PMSAv7, the v7A/R Arm ARM defines that setting AP to 0b111
is an UNPREDICTABLE reserved combination. However, for v7M
this value is documented as having the same behaviour as 0b110:
read-only for both privileged and unprivileged. Accept this
value on an M profile core rather than treating it as a guest
error and a no-access page.

Backports commit 8638f1ad7403b63db880dadce38e6690b5d82b64 from qemu
2018-03-06 08:51:55 -05:00
Peter Maydell bfd6d3e59b
target/arm: Make disas_thumb2_insn() generate its own UNDEF exceptions
Refactor disas_thumb2_insn() so that it generates the code for raising
an UNDEF exception for invalid insns, rather than returning a flag
which the caller must check to see if it needs to generate the UNDEF
code. This brings the function in to line with the behaviour of
disas_thumb_insn() and disas_arm_insn().

Backports commit 2eea841c11096e8dcc457b80e21f3fbdc32d2590 from qemu
2018-03-06 08:50:18 -05:00
Michael Weiser 5fabebabee
target/arm: Fix stlxp for aarch64_be
ldxp loads two consecutive doublewords from memory regardless of CPU
endianness. On store, stlxp currently assumes to work with a 128bit
value and consequently switches order in big-endian mode. With this
change it packs the doublewords in reverse order in anticipation of the
128bit big-endian store operation interposing them so they end up in
memory in the right order. This makes it work for both MTTCG and !MTTCG.
It effectively implements the ARM ARM STLXP operation pseudo-code:

data = if BigEndian() then el1:el2 else el2:el1;

With this change an aarch64_be Linux 4.14.4 kernel succeeds to boot up
in system emulation mode.

Backports commit 0785557f8811133bd69be02aeccf018d47a26373 from qemu
2018-03-06 08:48:12 -05:00
Richard Henderson 7fe5f620df
tcg: Dynamically allocate TCGOps
With no fixed array allocation, we can't overflow a buffer.
This will be important as optimizations related to host vectors
may expand the number of ops used.

Use QTAILQ to link the ops together.

Backports commit 15fa08f8451babc88d733bd411d4c94976f9d0f8 from qemu
2018-03-05 16:34:40 -05:00
Richard Henderson 5f074f09ab
tcg: Remove TCGV_UNUSED* and TCGV_IS_UNUSED*
These are now trivial sets and tests against NULL. Unwrap.

Backports commit f764718d0cb30af9f1f8e1d6a33622cc05ca4155 from qemu
2018-03-05 15:58:15 -05:00
Alex Bennée 8e973e762d
target/*helper: don't check retaddr before calling cpu_restore_state
cpu_restore_state officially supports being passed an address it can't
resolve the state for. As a result the checks in the helpers are
superfluous and can be removed. This makes the code consistent with
other users of cpu_restore_state.

Of course this does nothing to address what to do if cpu_restore_state
can't resolve the state but so far it seems this is handled elsewhere.

The change was made with included coccinelle script.

Backports commit 65255e8efdd5fca602bcc4ff61a879939ff75f4f from qemu
2018-03-05 14:47:41 -05:00
Peter Xu 1bb34aadf9
cpu: refactor cpu_address_space_init()
Normally we create an address space for that CPU and pass that address
space into the function. Let's just do it inside to unify address space
creations. It'll simplify my next patch to rename those address spaces.

Backports commit 80ceb07a83375e3a0091591f96bd47bce2f640ce from qemu
2018-03-05 14:39:25 -05:00
Edgar E. Iglesias 60136b485c
target/arm: Extend PAR format determination
Now that do_ats_write() is entirely in control of whether to
generate a 32-bit PAR or a 64-bit PAR, we can make it use the
correct (complicated) condition for doing so.

Backports commit 1313e2d7e2cd8b21741e0cf542eb09dfc4188f79 from qemu
2018-03-05 14:08:50 -05:00
Peter Maydell 0dfb84ea50
target/arm: Remove fsr argument from get_phys_addr() and arm_tlb_fill()
All of the callers of get_phys_addr() and arm_tlb_fill() now ignore
the FSR values they return, so we can just remove the argument
entirely.

Backports commit bc52bfeb3be2052942b7dac8ba284f342ac9605b from qemu
2018-03-05 14:05:08 -05:00
Peter Maydell ec686af668
target/arm: Ignore fsr from get_phys_addr() in do_ats_write()
In do_ats_write(), rather than using the FSR value from get_phys_addr(),
construct the PAR values using the information in the ARMMMUFaultInfo
struct. This allows us to create a PAR of the correct format regardless
of what the translation table format is.

For the moment we leave the condition for "when should this be a
64 bit PAR" as it was previously; this will need to be fixed to
properly support AArch32 Hyp mode.

Backports commit 5efe9ed45dec775ebe91ce72bd805ee780d16064 from qemu
2018-03-05 14:01:26 -05:00
Peter Maydell 3a5701e030
target/arm: Use ARMMMUFaultInfo in deliver_fault()
Now that ARMMMUFaultInfo is guaranteed to have enough information
to construct a fault status code, we can pass it in to the
deliver_fault() function and let it generate the correct type
of FSR for the destination, rather than relying on the value
provided by get_phys_addr().

I don't think there are any cases the old code was getting
wrong, but this is more obviously correct.

Backports commit 681f9a89d201d7891e2c60dff5e5415d8f618518 from qemu
2018-03-05 13:59:50 -05:00
Peter Maydell 4d666dbb99
target/arm: Convert get_phys_addr_pmsav8() to not return FSC values
Make get_phys_addr_pmsav8() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit 3f551b5b7380ff131fe22944aa6f5b166aa13caf from qemu
2018-03-05 13:57:33 -05:00
Peter Maydell 3eb4a2ea84
target/arm: Convert get_phys_addr_pmsav7() to not return FSC values
Make get_phys_addr_pmsav7() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit 9375ad15338b24e06109071ac3a85df48a2cc2e6 from qemu
2018-03-05 13:55:20 -05:00
Peter Maydell 79b2c4b1e7
target/arm: Convert get_phys_addr_pmsav5() to not return FSC values
Make get_phys_addr_pmsav5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Note that PMSAv5 does not define any guest-visible fault status
register, so the different "fsr" values we were previously
returning are entirely arbitrary. So we can just switch to using
the most appropriae fi->type values without worrying that we
need to special-case FaultInfo->FSC conversion for PMSAv5.

Backports commit 53a4e5c5b07b2f50c538511b74b0d3d4964695ea from qemu
2018-03-05 13:54:05 -05:00
Peter Maydell 013e7873ee
target/arm: Convert get_phys_addr_lpae() to not return FSC values
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit da909b2c23a68e57bbcb6be98229e40df606f0c8 from qemu
2018-03-05 13:52:18 -05:00
Peter Maydell c6496ec00a
target/arm: Convert get_phys_addr_v6() to not return FSC values
Make get_phys_addr_v6() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit f06cf243945ccb24cb9578304306ae7fcb4cf3fd from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 4ccf3c3927
target/arm: Convert get_phys_addr_v5() to not return FSC values
Make get_phys_addr_v5() return a fault type in the ARMMMUFaultInfo
structure, which we convert to the FSC at the callsite.

Backports commit f989983e8dc9be6bc3468c6dbe46fcb1501a740c from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 457e4f35ac
target/arm: Remove fsr argument from arm_ld*_ptw()
All the callers of arm_ldq_ptw() and arm_ldl_ptw() ignore the value
that those functions store in the fsr argument on failure: if they
return failure to their callers they will always overwrite the fsr
value with something else.

Remove the argument from these functions and S1_ptw_translate().
This will simplify removing fsr from the calling functions.

Backports commit 3795a6de9f7ec4a7e3dcb8bf02a88a014147b0b0 from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 211cbde764
target/arm: Provide fault type enum and FSR conversion functions
Currently get_phys_addr() and its various subfunctions return
a hard-coded fault status register value for translation
failures. This is awkward because FSR values these days may
be either long-descriptor format or short-descriptor format.
Worse, the right FSR type to use doesn't depend only on the
translation table being walked -- some cases, like fault
info reported to AArch32 EL2 for some kinds of ATS operation,
must be in long-descriptor format even if the translation
table being walked was short format. We can't get those cases
right with our current approach.

Provide fields in the ARMMMUFaultInfo struct which allow
get_phys_addr() to provide sufficient information for a caller to
construct an FSR value themselves, and utility functions which do
this for both long and short format FSR values, as a first step in
switching get_phys_addr() and its children to only returning the
failure cause in the ARMMMUFaultInfo struct.

Backports commit 1fa498fe0de979030bd1f481046e9f1c5574a584 from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 8fe6b6c308
target/arm: Implement TT instruction
Implement the TT instruction which queries the security
state and access permissions of a memory location.

Backports commit 5158de241b0fb344a6c948dfcbc4e611ab5fafbe from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 4e5ec9c0dc
target/arm: Factor MPU lookup code out of get_phys_addr_pmsav8()
For the TT instruction we're going to need to do an MPU lookup that
also tells us which MPU region the access hit. This requires us
to do the MPU lookup without first doing the SAU security access
check, so pull the MPU lookup parts of get_phys_addr_pmsav8()
out into their own function.

The TT instruction also needs to know the MPU region number which
the lookup hit, so provide this information to the caller of the
MPU lookup code, even though get_phys_addr_pmsav8() doesn't
need to know it.

Backports commit 54317c0ff3a3c0f6b2c3a1d3c8b5d93686a86d24 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell c441b19d76
target/arm: Create new arm_v7m_mmu_idx_for_secstate_and_priv()
The TT instruction is going to need to look up the MMU index
for a specified security and privilege state. Refactor the
existing arm_v7m_mmu_idx_for_secstate() into a version that
lets you specify the privilege state and one that uses the
current state of the CPU.

Backports commit ec8e3340286a87d3924c223d60ba5c994549f796 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 89acdeb9af
target/arm: Split M profile MNegPri mmu index into user and priv
For M profile, we currently have an mmu index MNegPri for
"requested execution priority negative". This fails to
distinguish "requested execution priority negative, privileged"
from "requested execution priority negative, usermode", but
the two can return different results for MPU lookups. Fix this
by splitting MNegPri into MNegPriPriv and MNegPriUser, and
similarly for the Secure equivalent MSNegPri.

This takes us from 6 M profile MMU modes to 8, which means
we need to bump NB_MMU_MODES; this is OK since the point
where we are forced to reduce TLB sizes is 9 MMU modes.

(It would in theory be possible to stick with 6 MMU indexes:
{mpu-disabled,user,privileged} x {secure,nonsecure} since
in the MPU-disabled case the result of an MPU lookup is
always the same for both user and privileged code. However
we would then need to rework the TB flags handling to put
user/priv into the TB flags separately from the mmuidx.
Adding an extra couple of mmu indexes is simpler.)

Backports commit 62593718d77c06ad2b5e942727cead40775d2395 from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell d877985eea
target/arm: Add missing M profile case to regime_is_user()
When we added the ARMMMUIdx_MSUser MMU index we forgot to
add it to the case statement in regime_is_user(), so we
weren't treating it as unprivileged when doing MPU lookups.
Correct the omission.

Backports commit 871bec7c44a453d9cab972ce1b5d12e1af0545ab from qemu
2018-03-05 13:48:31 -05:00
Peter Maydell 999080382f
target/arm: Allow explicit writes to CONTROL.SPSEL in Handler mode
In ARMv7M the CPU ignores explicit writes to CONTROL.SPSEL
in Handler mode. In v8M the behaviour is slightly different:
writes to the bit are permitted but will have no effect.

We've already done the hard work to handle the value in
CONTROL.SPSEL being out of sync with what stack pointer is
actually in use, so all we need to do to fix this last loose
end is to update the condition we use to guard whether we
call write_v7m_control_spsel() on the register write.

Backports commit 83d7f86d3d27473c0aac79c1baaa5c2ab01b02d9 from qemu
2018-03-05 13:48:30 -05:00
Peter Maydell 6713884243
target/arm: Handle SPSEL and current stack being out of sync in MSP/PSP reads
For v8M it is possible for the CONTROL.SPSEL bit value and the
current stack to be out of sync. This means we need to update
the checks used in reads and writes of the PSP and MSP special
registers to use v7m_using_psp() rather than directly checking
the SPSEL bit in the control register.

Backports commit 1169d3aa5b19adca9384d954d80e1f48da388284 from qemu
2018-03-05 13:48:30 -05:00
Peter Maydell 352a7b2501
target/arm: Generate UNDEF for 32-bit Thumb2 insns
The refactoring of commit 296e5a0a6c3935 has a nasty bug:
it accidentally dropped the generation of code to raise
the UNDEF exception when disas_thumb2_insn() returns nonzero.
This means that 32-bit Thumb2 instruction patterns that
ought to UNDEF just act like nops instead. This is likely
to break any number of things, including the kernel's "disable
the FPU and use the UNDEF exception to identify when to turn
it back on again" trick.

Backports commit 7472e2efb049ea65a6a5e7261b78ebf5c561bc2f from qemu
2018-03-05 13:48:29 -05:00
Peter Maydell c01b9a3cfe
arm: check regime, not current state, for ATS write PAR format
In do_ats_write(), rather than using extended_addresses_enabled() to
decide whether the value we get back from get_phys_addr() is a 64-bit
format PAR or a 32-bit one, use arm_s1_regime_using_lpae_format().

This is not really the correct answer, because the PAR format
depends on the AT instruction being used, not just on the
translation regime. However getting this correct requires a
significant refactoring, so that get_phys_addr() returns raw
information about the fault which the caller can then assemble
into a suitable FSR/PAR/syndrome for its purposes, rather than
get_phys_addr() returning a pre-formatted FSR.

However this change at least improves the situation by making
the PAR work correctly for address translation operations done
at AArch64 EL2 on the EL2 translation regime. In particular,
this is necessary for Xen to be able to run in our emulation,
so this seems like a safer interim fix given that we are in freeze.

Backports commit 50cd71b0d347c74517dcb7da447fe657fca57d9c from qemu
2018-03-05 13:48:28 -05:00
Peter Maydell 175b632c91
target/arm: Report GICv3 sysregs present in ID registers if needed
The CPU ID registers ID_AA64PFR0_EL1, ID_PFR1_EL1 and ID_PFR1
have a field for reporting presence of GICv3 system registers.
We need to report this field correctly in order for Xen to
work as a guest inside QEMU emulation. We mustn't incorrectly
claim the sysregs exist when they don't, though, or Linux will
crash.

Unfortunately the way we've designed the GICv3 emulation in QEMU
puts the system registers as part of the GICv3 device, which
may be created after the CPU proper has been realized. This
means that we don't know at the point when we define the ID
registers what the correct value is. Handle this by switching
them to calling a function at runtime to read the value, where
we can fill in the GIC field appropriately.

Backports commit 96a8b92ed8f02d5e86ad380d3299d9f41f99b072 from qemu
2018-03-05 13:48:28 -05:00
Richard Henderson a58eb310eb
target/arm: Use helper_retaddr in stxp helpers
We use raw memory primitives along the !parallel_cpus paths in order to
simplify the endianness handling. Because of that, we did not benefit
from the generic changes to cpu_ldst_user_only_template.h.

The simplest fix is to manipulate helper_retaddr here.

Backports commit 3bdb5fcc9a08a9a47ce30c4e0c2d64c95190b49d from qemu
2018-03-05 13:48:28 -05:00
Emilio G. Cota 208014df9e
arm/translate-a64: mark path as unreachable to eliminate warning
Fixes the following warning when compiling with gcc 5.4.0 with -O1
optimizations and --enable-debug:

target/arm/translate-a64.c: In function ‘aarch64_tr_translate_insn’:
target/arm/translate-a64.c:2361:8: error: ‘post_index’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (!post_index) {
^
target/arm/translate-a64.c:2307:10: note: ‘post_index’ was declared here
bool post_index;
^
target/arm/translate-a64.c:2386:8: error: ‘writeback’ may be used uninitialized in this function [-Werror=maybe-uninitialized]
if (writeback) {
^
target/arm/translate-a64.c:2308:10: note: ‘writeback’ was declared here
bool writeback;
^

Note that idx comes from selecting 2 bits, and therefore its value
can be at most 3.

Backports commit 5ca66278c859bb1ded243755aeead2be6992ce73 from qemu
2018-03-05 11:40:11 -05:00
Peter Maydell 33d42df60c
translate.c: Fix usermode big-endian AArch32 LDREXD and STREXD
For AArch32 LDREXD and STREXD, architecturally the 32-bit word at the
lowest address is always Rt and the one at addr+4 is Rt2, even if the
CPU is big-endian. Our implementation does these with a single
64-bit store, so if we're big-endian then we need to put the two
32-bit halves together in the opposite order to little-endian,
so that they end up in the right places. We were trying to do
this with the gen_aa32_frob64() function, but that is not correct
for the usermode emulator, because there there is a distinction
between "load a 64 bit value" (which does a BE 64-bit access
and doesn't need swapping) and "load two 32 bit values as one
64 bit access" (where we still need to do the swapping, like
system mode BE32).

Backports commit 3448d47b3172015006b79197eb5a69826c6a7b6d from qemu
2018-03-05 11:39:29 -05:00
Andrew Baumann 5250db33b5
arm: implement cache/shareability attribute bits for PAR registers
On a successful address translation instruction, PAR is supposed to
contain cacheability and shareability attributes determined by the
translation. We previously returned 0 for these bits (in line with the
general strategy of ignoring caches and memory attributes), but some
guest OSes may depend on them.

This patch collects the attribute bits in the page-table walk, and
updates PAR with the correct attributes for all LPAE translations.
Short descriptor formats still return 0 for these bits, as in the
prior implementation.

Backports commit 5b2d261d60caf9d988d91ca1e02392d6fc8ea104 from qemu
2018-03-05 11:35:28 -05:00
Stefano Stabellini 1212c9b73c
fix WFI/WFE length in syndrome register
WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.

Pass the instruction length to HELPER(wfi), use it to decrement pc
appropriately and to pass an is_16bit flag to syn_wfx, which sets
ARM_EL_IL_SHIFT if needed.

Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.

Backports commit 58803318e5a546b2eb0efd7a053ed36b6c29ae6f from qemu
2018-03-05 11:21:51 -05:00
Richard Henderson 28061c2e59
qom: Introduce CPUClass.tcg_initialize
Move target cpu tcg initialization to common code,
called from cpu_exec_realizefn.

Backports commit 55c3ceef61fcf06fc98ddc752b7cce788ce7680b from qemu
2018-03-05 09:49:26 -05:00
Peter Maydell 0c06666800
target/arm: Implement SG instruction corner cases
The common situation of the SG instruction is that it is
executed from S&NSC memory by a CPU in NS state. That case
is handled by v7m_handle_execute_nsc(). However the instruction
also has defined behaviour in a couple of other cases:
* SG instruction in NS memory (behaves as a NOP)
* SG in S memory but CPU already secure (clears IT bits and
does nothing else)
* SG instruction in v8M without Security Extension (NOP)

These can be implemented in translate.c.

Backports commit 76eff04d166b8fe747adbe82de8b7e060e668ff9 from qemu
2018-03-05 03:47:20 -05:00
Peter Maydell 272427b4a0
target/arm: Support some Thumb insns being always unconditional
A few Thumb instructions are always unconditional even inside an
IT block (as opposed to being UNPREDICTABLE if used inside an
IT block): BKPT, the v8M SG instruction, and the A profile
HLT (debug halt) instruction.

This means we need to suppress the jump-over-instruction-on-condfail
code generation (though the IT state still advances as usual and
subsequent insns in the IT block may be conditional).

Backports commit dcf14dfb704519846f396a376339ebdb93eaf049 from qemu
2018-03-05 03:46:10 -05:00
Peter Maydell 7a293cd7cc
target-arm: Simplify insn_crosses_page()
Recent changes have left insn_crosses_page() more complicated
than it needed to be:
* it's only called from thumb_tr_translate_insn() so we know
for certain that we're looking at a Thumb insn
* the caller's check for dc->pc >= dc->next_page_start - 3
means that dc->pc can't possibly be 4 aligned, so there's
no need to check that (the check was partly there to ensure
that we didn't treat an ARM insn as Thumb, I think)
* we now have thumb_insn_is_16bit() which lets us do a precise
check of the length of the next insn, rather than opencoding
an inaccurate check

Simplify it down to just loading the first half of the insn
and calling thumb_insn_is_16bit() on it.

Backports commit 5b8d7289e9e92a0d7bcecb93cd189e245fef10cd from qemu
2018-03-05 03:44:54 -05:00
Peter Maydell 96f86f472a
target/arm: Pull Thumb insn word loads up to top level
Refactor the Thumb decode to do the loads of the instruction words at
the top level rather than only loading the second half of a 32-bit
Thumb insn in the middle of the decode.

This is simple apart from the awkward case of Thumb1, where the
BL/BLX prefix and suffix instructions live in what in Thumb2 is the
32-bit insn space. To handle these we decode enough to identify
whether we're looking at a prefix/suffix that we handle as a 16 bit
insn, or a prefix that we're going to merge with the following suffix
to consider as a 32 bit insn. The translation of the 16 bit cases
then moves from disas_thumb2_insn() to disas_thumb_insn().

The refactoring has the benefit that we don't need to pass the
CPUARMState* down into the decoder code any more, but the major
reason for doing this is that some Thumb instructions must be always
unconditional regardless of the IT state bits, so we need to know the
whole insn before we emit the "skip this insn if the IT bits and cond
state tell us to" code. (The always unconditional insns are BKPT,
HLT and SG; the last of these is 32 bits.)

Backports commit 296e5a0a6c393553079a641c50521ae33ff89324 from qemu
2018-03-05 03:43:38 -05:00
Peter Maydell b85d617bda
target-arm: Don't check for "Thumb2 or M profile" for not-Thumb1
The code which implements the Thumb1 split BL/BLX instructions
is guarded by a check on "not M or THUMB2". All we really need
to check here is "not THUMB2" (and we assume that elsewhere too,
eg in the ARCH(6T2) test that UNDEFs the Thumb2 insns).

This doesn't change behaviour because all M profile cores
have Thumb2 and so ARM_FEATURE_M implies ARM_FEATURE_THUMB2.
(v6M implements a very restricted subset of Thumb2, but we
can cross that bridge when we get to it with appropriate
feature bits.)

Backports commit 6b8acf256df09c8a8dd7dcaa79b06eaff4ad63f7 from qemu
2018-03-05 03:34:48 -05:00
Peter Maydell ee9b8a20c9
target/arm: Implement secure function return
Secure function return happens when a non-secure function has been
called using BLXNS and so has a particular magic LR value (either
0xfefffffe or 0xfeffffff). The function return via BX behaves
specially when the new PC value is this magic value, in the same
way that exception returns are handled.

Adjust our BX excret guards so that they recognize the function
return magic number as well, and perform the function-return
unstacking in do_v7m_exception_exit().

Backports commit d02a8698d7ae2bfed3b11fe5b064cb0aa406863b from qemu
2018-03-05 03:33:42 -05:00
Peter Maydell e312993f1f
target/arm: Implement BLXNS
Implement the BLXNS instruction, which allows secure code to
call non-secure code.

Backports commit 3e3fa230e3b8ffe119f14ba57a6bc677a411be57 from qemu
2018-03-05 03:31:59 -05:00
Peter Maydell 2c4578f46e
target/arm: Implement SG instruction
Implement the SG instruction, which we emulate 'by hand' in the
exception handling code path.

Backports commit 333e10c51ef5876ced26f77b61b69ce0f83161a9 from qemu
2018-03-05 03:28:28 -05:00
Peter Maydell 19ecd4f732
target/arm: Add M profile secure MMU index values to get_a32_user_mem_index()
Add the M profile secure MMU index values to the switch in
get_a32_user_mem_index() so that LDRT/STRT work correctly
rather than asserting at translate time.

Backports commit b9f587d62cebed427206539750ebf59bde4df422 from qemu
2018-03-05 03:25:54 -05:00
Emilio G. Cota 5fae6dd433
tcg: remove addr argument from lookup_tb_ptr
It is unlikely that we will ever want to call this helper passing
an argument other than the current PC. So just remove the argument,
and use the pc we already get from cpu_get_tb_cpu_state.

This change paves the way to having a common "tb_lookup" function.

Backports commit 7f11636dbee89b0e4d03e9e2b96e14649a7db778 from qemu
2018-03-05 02:16:34 -05:00
Peter Maydell 059f238f11
target/arm: Factor out "get mmuidx for specified security state"
For the SG instruction and secure function return we are going
to want to do memory accesses using the MMU index of the CPU
in secure state, even though the CPU is currently in non-secure
state. Write arm_v7m_mmu_idx_for_secstate() to do this job,
and use it in cpu_mmu_index().

Backports commit b81ac0eb6315e602b18439961e0538538e4aed4f from qemu
2018-03-05 02:00:23 -05:00
Peter Maydell 6958a4763d
target/arm: Fix calculation of secure mm_idx values
In cpu_mmu_index() we try to do this:
if (env->v7m.secure) {
mmu_idx += ARMMMUIdx_MSUser;
}
but it will give the wrong answer, because ARMMMUIdx_MSUser
includes the 0x40 ARM_MMU_IDX_M field, and so does the
mmu_idx we're adding to, and we'll end up with 0x8n rather
than 0x4n. This error is then nullified by the call to
arm_to_core_mmu_idx() which masks out the high part, but
we're about to factor out the code that calculates the
ARMMMUIdx values so it can be used without passing it through
arm_to_core_mmu_idx(), so fix this bug first.

Backports commit fe768788d29597ee56fc11ba2279d502c2617457 from qemu
2018-03-05 01:58:42 -05:00
Peter Maydell 7988aec017
target/arm: Implement security attribute lookups for memory accesses
Implement the security attribute lookups for memory accesses
in the get_phys_addr() functions, causing these to generate
various kinds of SecureFault for bad accesses.

The major subtlety in this code relates to handling of the
case when the security attributes the SAU assigns to the
address don't match the current security state of the CPU.

In the ARM ARM pseudocode for validating instruction
accesses, the security attributes of the address determine
whether the Secure or NonSecure MPU state is used. At face
value, handling this would require us to encode the relevant
bits of state into mmu_idx for both S and NS at once, which
would result in our needing 16 mmu indexes. Fortunately we
don't actually need to do this because a mismatch between
address attributes and CPU state means either:
* some kind of fault (usually a SecureFault, but in theory
perhaps a UserFault for unaligned access to Device memory)
* execution of the SG instruction in NS state from a
Secure & NonSecure code region

The purpose of SG is simply to flip the CPU into Secure
state, so we can handle it by emulating execution of that
instruction directly in arm_v7m_cpu_do_interrupt(), which
means we can treat all the mismatch cases as "throw an
exception" and we don't need to encode the state of the
other MPU bank into our mmu_idx values.

This commit doesn't include the actual emulation of SG;
it also doesn't include implementation of the IDAU, which
is a per-board way to specify hard-coded memory attributes
for addresses, which override the CPU-internal SAU if they
specify a more secure setting than the SAU is programmed to.

Backports commit 35337cc391245f251bfb9134f181c33e6375d6c1 from qemu
2018-03-05 01:57:07 -05:00
Peter Maydell f9b4381ce0
nvic: Implement Security Attribution Unit registers
Implement the register interface for the SAU: SAU_CTRL,
SAU_TYPE, SAU_RNR, SAU_RBAR and SAU_RLAR. None of the
actual behaviour is implemented here; registers just
read back as written.

When the CPU definition for Cortex-M33 is eventually
added, its initfn will set cpu->sau_sregion, in the same
way that we currently set cpu->pmsav7_dregion for the
M3 and M4.

Number of SAU regions is typically a configurable
CPU parameter, but this patch doesn't provide a
QEMU CPU property for it. We can easily add one when
we have a board that requires it.

Backports commit 9901c576f6c02d43206e5faaf6e362ab7ea83246 from qemu
2018-03-05 01:55:11 -05:00
Peter Maydell 3da3a3fb41
target/arm: Add v8M support to exception entry code
Add support for v8M and in particular the security extension
to the exception entry code. This requires changes to:
* calculation of the exception-return magic LR value
* push the callee-saves registers in certain cases
* clear registers when taking non-secure exceptions to avoid
leaking information from the interrupted secure code
* switch to the correct security state on entry
* use the vector table for the security state we're targeting

Backports commit d3392718e1fcf0859fb7c0774a8e946bacb8419c from qemu
2018-03-05 01:51:22 -05:00
Peter Maydell 39466771d6
target/arm: Add support for restoring v8M additional state context
For v8M, exceptions from Secure to Non-Secure state will save
callee-saved registers to the exception frame as well as the
caller-saved registers. Add support for unstacking these
registers in exception exit when necessary.

Backports commit 907bedb3f3ce134c149599bd9cb61856d811b8ca from qemu
2018-03-05 01:47:25 -05:00
Peter Maydell 2feecbac0d
target/arm: Update excret sanity checks for v8M
In v8M, more bits are defined in the exception-return magic
values; update the code that checks these so we accept
the v8M values when the CPU permits them.

Backports commit bfb2eb52788b9605ef2fc9bc72683d4299117fde from qemu
2018-03-05 01:44:33 -05:00
Peter Maydell 33d2358c91
target/arm: Add new-in-v8M SFSR and SFAR
Add the new M profile Secure Fault Status Register
and Secure Fault Address Register.

Backports commit bed079da04dd9e0e249b9bc22bca8dce58b67f40 from qemu
2018-03-05 01:42:52 -05:00
Peter Maydell 7af730ed3e
target/arm: Don't warn about exception return with PC low bit set for v8M
In the v8M architecture, return from an exception to a PC which
has bit 0 set is not UNPREDICTABLE; it is defined that bit 0
is discarded [R_HRJH]. Restrict our complaint about this to v7M.

Backports commit 4e4259d3c574a8e89c3af27bcb84bc19a442efb1 from qemu
2018-03-05 01:41:51 -05:00
Peter Maydell 2aea283c4f
target/arm: Warn about restoring to unaligned stack
Attempting to do an exception return with an exception frame that
is not 8-aligned is UNPREDICTABLE in v8M; warn about this.
(It is not UNPREDICTABLE in v7M, and our implementation can
handle the merely-4-aligned case fine, so we don't need to
do anything except warn.)

Backports commit cb484f9a6e790205e69d9a444c3e353a3a1cfd84 from qemu
2018-03-05 01:40:40 -05:00
Peter Maydell 5063ca11ab
target/arm: Check for xPSR mismatch usage faults earlier for v8M
ARM v8M specifies that the INVPC usage fault for mismatched
xPSR exception field and handler mode bit should be checked
before updating the PSR and SP, so that the fault is taken
with the existing stack frame rather than by pushing a new one.
Perform this check in the right place for v8M.

Since v7M specifies in its pseudocode that this usage fault
check should happen later, we have to retain the original
code for that check rather than being able to merge the two.
(The distinction is architecturally visible but only in
very obscure corner cases like attempting an invalid exception
return with an exception frame in read only memory.)

Backports commit 224e0c300a0098fb577a03bd29d774d0769f632a from qemu
2018-03-05 01:39:39 -05:00
Peter Maydell 6f08acdcfe
target/arm: Restore SPSEL to correct CONTROL register on exception return
On exception return for v8M, the SPSEL bit in the EXC_RETURN magic
value should be restored to the SPSEL bit in the CONTROL register
banked specified by the EXC_RETURN.ES bit.

Add write_v7m_control_spsel_for_secstate() which behaves like
write_v7m_control_spsel() but allows the caller to specify which
CONTROL bank to use, reimplement write_v7m_control_spsel() in
terms of it, and use it in exception return.

Backports commit 3f0cddeee1f266d43c956581f3050058360a810d from qemu
2018-03-05 01:35:17 -05:00
Peter Maydell 0bb50b9a7e
target/arm: Restore security state on exception return
Now that we can handle the CONTROL.SPSEL bit not necessarily being
in sync with the current stack pointer, we can restore the correct
security state on exception return. This happens before we start
to read registers off the stack frame, but after we have taken
possible usage faults for bad exception return magic values and
updated CONTROL.SPSEL.

Backports commit 3919e60b6efd9a86a0e6ba637aa584222855ac3a from qemu
2018-03-05 01:31:58 -05:00
Peter Maydell c7b5fccfb8
target/arm: Prepare for CONTROL.SPSEL being nonzero in Handler mode
In the v7M architecture, there is an invariant that if the CPU is
in Handler mode then the CONTROL.SPSEL bit cannot be nonzero.
This in turn means that the current stack pointer is always
indicated by CONTROL.SPSEL, even though Handler mode always uses
the Main stack pointer.

In v8M, this invariant is removed, and CONTROL.SPSEL may now
be nonzero in Handler mode (though Handler mode still always
uses the Main stack pointer). In preparation for this change,
change how we handle this bit: rename switch_v7m_sp() to
the now more accurate write_v7m_control_spsel(), and make it
check both the handler mode state and the SPSEL bit.

Note that this implicitly changes the point at which we switch
active SP on exception exit from before we pop the exception
frame to after it.

Backports commit de2db7ec894f11931932ca78cd14a8d2b1389d5b from qemu
2018-03-05 01:29:54 -05:00
Peter Maydell 8036c5b3de
target/arm: Don't switch to target stack early in v7M exception return
Currently our M profile exception return code switches to the
target stack pointer relatively early in the process, before
it tries to pop the exception frame off the stack. This is
awkward for v8M for two reasons:
* in v8M the process vs main stack pointer is not selected
purely by the value of CONTROL.SPSEL, so updating SPSEL
and relying on that to switch to the right stack pointer
won't work
* the stack we should be reading the stack frame from and
the stack we will eventually switch to might not be the
same if the guest is doing strange things

Change our exception return code to use a 'frame pointer'
to read the exception frame rather than assuming that we
can switch the live stack pointer this early.

Backports commit 5b5223997c04b769bb362767cecb5f7ec382c5f0 from qemu
2018-03-05 01:26:05 -05:00
Jan Kiszka ae16a26c20
arm: Fix SMC reporting to EL2 when QEMU provides PSCI
This properly forwards SMC events to EL2 when PSCI is provided by QEMU
itself and, thus, ARM_FEATURE_EL3 is off.

Found and tested with the Jailhouse hypervisor. Solution based on
suggestions by Peter Maydell.

Backports commit 77077a83006c3c9bdca496727f1735a3c5c5355d from qemu
2018-03-05 01:19:22 -05:00
Peter Maydell f0569ba11a
target/arm: Remove out of date ARM ARM section references in A64 decoder
In the A64 decoder, we have a lot of references to section numbers
from version A.a of the v8A ARM ARM (DDI0487). This version of the
document is now long obsolete (we are currently on revision B.a),
and various intervening versions renumbered all the sections.

The most recent B.a version of the document doesn't assign
section numbers at all to the individual instruction classes
in the way that the various A.x versions did. The simplest thing
to do is just to delete all the out of date C.x.x references.

Backports commit 4ce31af4aeb8471f6a913de7c59d3bde1fc4f03d from qemu
2018-03-05 01:05:53 -05:00
Peter Maydell 72dadc6518
target/arm: Handle banking in negative-execution-priority check in cpu_mmu_index()
Now that we have a banked FAULTMASK register and banked exceptions,
we can implement the correct check in cpu_mmu_index() for whether
the MPU_CTRL.HFNMIENA bit's effect should apply. This bit causes
handlers which have requested a negative execution priority to run
with the MPU disabled. In v8M the test has to check this for the
current security state and so takes account of banking.

Backports relevant part of commit 5d4791991d4de12e83d44738417c9e964167b6e8 from qemu
2018-03-05 00:54:28 -05:00
Peter Maydell 4b8bdda695
target/arm: Implement MSR/MRS access to NS banked registers
In v8M the MSR and MRS instructions have extra register value
encodings to allow secure code to access the non-secure banked
version of various special registers.

(We don't implement the MSPLIM_NS or PSPLIM_NS aliases, because
we don't currently implement the stack limit registers at all.)

Backports commit 50f11062d4c896408731d6a286bcd116d1e08465 from qemu
2018-03-05 00:53:13 -05:00
Igor Mammedov 607bc396c3
arm: drop intermediate cpu_model -> cpu type parsing and use cpu type directly
Backports defines from commit ba1ba5cca3962a9cc400c713c736b4fb8db1f38e from qemu
2018-03-05 00:10:21 -05:00
Richard Henderson c5e952978c
target/arm: Avoid an extra temporary for store_exclusive
Instead of copying addr to a local temp, reuse the value (which we
have just compared as equal) already saved in cpu_exclusive_addr.

Backports commit 37e29a64254bf82a1901784fcca17c25f8164c2f from qemu
2018-03-04 23:17:50 -05:00
Jaroslaw Pelczar 7fded6c15c
AArch64: Fix single stepping of ERET instruction
Previously when single stepping through ERET instruction via GDB
would result in debugger entering the "next" PC after ERET instruction.
When debugging in kernel mode, this will also cause unintended behavior,
because debugger will try to access memory from EL0 point of view.

Backports commit dddbba9943ef6a81c8702e4a50cb0a8b1a4201fe from qemu
2018-03-04 23:15:30 -05:00
Peter Maydell 6a951f17ed
target/arm: Rename 'type' to 'excret' in do_v7m_exception_exit()
In the v7M and v8M ARM ARM, the magic exception return values are
referred to as EXC_RETURN values, and in QEMU we use V7M_EXCRET_*
constants to define bits within them. Rename the 'type' variable
which holds the exception return value in do_v7m_exception_exit()
to excret, making it clearer that it does hold an EXC_RETURN value.

Backports commit 351e527a613147aa2a2e6910f92923deef27ee48 from qemu
2018-03-04 23:14:22 -05:00
Peter Maydell 1301cb1771
target/arm: Add and use defines for EXCRET constants
The exception-return magic values get some new bits in v8M, which
makes some bit definitions for them worthwhile.

We don't use the bit definitions for the switch on the low bits
which checks the return type for v7M, because this is defined
in the v7M ARM ARM as a set of valid values rather than via
per-bit checks.

Backports commit 4d1e7a4745c050f7ccac49a1c01437526b5130b5 from qemu
2018-03-04 23:12:37 -05:00
Peter Maydell aa71933721
target/arm: Remove unnecessary '| 0xf0000000' from do_v7m_exception_exit()
In do_v7m_exception_exit(), there's no need to force the high 4
bits of 'type' to 1 when calling v7m_exception_taken(), because
we know that they're always 1 or we could not have got to this
"handle return to magic exception return address" code. Remove
the unnecessary ORs.

Backports commit 7115cdf5782922611bcc44c89eec5990db7f6466 from qemu
2018-03-04 23:11:13 -05:00
Peter Maydell 2718aa8233
target/arm: Get PRECISERR and IBUSERR the right way round
For a bus fault, the M profile BFSR bit PRECISERR means a bus
fault on a data access, and IBUSERR means a bus fault on an
instruction access. We had these the wrong way around; fix this.

Backports commit c6158878650c01b2c753b2ea7d0967c8fe5ca59e from qemu
2018-03-04 23:10:33 -05:00
Peter Maydell ceccd92940
target/arm: Clear exclusive monitor on v7M reset, exception entry/exit
For M profile we must clear the exclusive monitor on reset, exception
entry and exception exit. We weren't doing any of these things; fix
this bug.

Backports commit dc3c4c14f0f12854dbd967be3486f4db4e66d25b from qemu
2018-03-04 23:09:41 -05:00
Peter Maydell 2a9b62c12b
target/arm: Clear exclusive monitor on v7M reset, exception entry/exit
For M profile we must clear the exclusive monitor on reset, exception
entry and exception exit. We weren't doing any of these things; fix
this bug.

Backports commit dc3c4c14f0f12854dbd967be3486f4db4e66d25b from qemu
2018-03-04 23:08:31 -05:00
Peter Maydell 09ca9356a3
target/arm: Use M_REG_NUM_BANKS rather than hardcoding 2
Use a symbolic constant M_REG_NUM_BANKS for the array size for
registers which are banked by M profile security state, rather
than hardcoding lots of 2s.

Backports commit 4a16724f06ead684a5962477a557c26c677c2729 from qemu
2018-03-04 23:07:30 -05:00
Peter Maydell 8d02ee3b51
target/arm: Implement new do_transaction_failed hook
Implement the new do_transaction_failed hook for ARM, which should
cause the CPU to take a prefetch abort or data abort.

Backports commit c79c0a314c43b78f6326d5f137bdbafdbf8e9766 from qemu
2018-03-04 21:29:05 -05:00
Peter Maydell 2070ef1c37
boards.h: Define new flag ignore_memory_transaction_failures
Define a new MachineClass field ignore_memory_transaction_failures.
If this is flag is true then the CPU will ignore memory transaction
failures which should cause the CPU to take an exception due to an
access to an unassigned physical address; the transaction will
instead return zero (for a read) or be ignored (for a write). This
should be set only by legacy board models which rely on the old
RAZ/WI behaviour for handling devices that QEMU does not yet model.
New board models should instead use "unimplemented-device" for all
memory ranges where the guest will attempt to probe for a device that
QEMU doesn't implement and a stub device is required.

We need this for ARM boards, where we're about to implement support for
generating external aborts on memory transaction failures. Too many
of our legacy board models rely on the RAZ/WI behaviour and we
would break currently working guests when their "probe for device"
code provoked an external abort rather than a RAZ.

Backports commit ed860129acd3fcd0b1e47884e810212aaca4d21b from qemu
2018-03-04 21:27:15 -05:00
Peter Maydell 4b816fe0aa
target/arm: Implement BXNS, and banked stack pointers
Implement the BXNS v8M instruction, which is like BX but will do a
jump-and-switch-to-NonSecure if the branch target address has bit 0
clear.

This is the first piece of code which implements "switch to the
other security state", so the commit also includes the code to
switch the stack pointers around, which is the only complicated
part of switching security state.

BLXNS is more complicated than just "BXNS but set the link register",
so we leave it for a separate commit.

Backports commit fb602cb726b3ebdd01ef3b1732d74baf9fee7ec9 from qemu
2018-03-04 21:21:23 -05:00
Peter Maydell 221232fb35
target/arm: Move regime_is_secure() to target/arm/internals.h
Move the regime_is_secure() utility function to internals.h;
we are going to want to call it from translate.c.

Backports commit 61fcd69b0db268e7612b07fadc436b93def91768 from qemu
2018-03-04 21:14:05 -05:00
Peter Maydell 07b9144ef2
target/arm: Make CFSR register banked for v8M
Make the CFSR register banked if v8M security extensions are enabled.

Not all the bits in this register are banked: the BFSR
bits [15:8] are shared between S and NS, and we store them
in the NS copy of the register.

Backports commit 334e8dad7a109d15cb20b090131374ae98682a50 from qemu
2018-03-04 21:12:55 -05:00
Peter Maydell 74c66cc2a9
target/arm: Make MMFAR banked for v8M
Make the MMFAR register banked if v8M security extensions are
enabled.

Backports commit c51a5cfc9fae82099028eb12cb1d064ee07f348e from qemu
2018-03-04 21:10:47 -05:00
Peter Maydell 4b24f6d87b
target/arm: Make CCR register banked for v8M
Make the CCR register banked if v8M security extensions are enabled.

This is slightly more complicated than the other "add banking"
patches because there is one bit in the register which is not
banked. We keep the live data in the NS copy of the register,
and adjust it on register reads and writes. (Since we don't
currently implement the behaviour that the bit controls, there
is nowhere else that needs to care.)

This patch includes the enforcement of the bits which are newly
RES1 in ARMv8M.

Backports commit 9d40cd8a68cfc7606f4548cc9e812bab15c6dc28 from qemu
2018-03-04 21:09:34 -05:00
Peter Maydell f88f4b5e31
target/arm: Make MPU_CTRL register banked for v8M
Make the MPU_CTRL register banked if v8M security extensions are
enabled.

Backports commit ecf5e8eae8b0b5fa41f00b53d67747b42fd1b8b9 from qemu
2018-03-04 21:08:16 -05:00
Peter Maydell 683830d5ac
target/arm: Make MPU_RNR register banked for v8M
Make the MPU_RNR register banked if v8M security extensions are
enabled.

Backports commit 1bc04a8880374407c4b12d82ceb8752e12ff5336 from qemu
2018-03-04 21:06:01 -05:00
Peter Maydell 5e14b33c65
target/arm: Make MPU_RBAR, MPU_RLAR banked for v8M
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.

We can freely add more items to vmstate_m_security without
breaking migration compatibility, because no CPU currently
has the ARM_FEATURE_M_SECURITY bit enabled and so this
subsection is not yet used by anything.

Backports commit 62c58ee0b24eafb44c06402fe059fbd7972eb409 from qemu
2018-03-04 21:04:41 -05:00
Peter Maydell 5b6e1e2150
target/arm: Make MPU_MAIR0, MPU_MAIR1 registers banked for v8M
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.

Backports commit 4125e6feb71c810ca38f0d8e66e748b472a9cc54 from qemu
2018-03-04 21:02:51 -05:00
Peter Maydell 3e35eee327
target/arm: Make VTOR register banked for v8M
Make the VTOR register banked if v8M security extensions are enabled.

Backports commit 45db7ba681ede57113a67499840e69ee586bcdf2 from qemu
2018-03-04 21:01:51 -05:00
Peter Maydell 59c6845ada
target/arm: Make CONTROL register banked for v8M
Make the CONTROL register banked if v8M security extensions are enabled.

Backports commit 8bfc26ea302ec03585d7258a7cf8938f76512730 from qemu
2018-03-04 21:00:58 -05:00
Peter Maydell 14cb6925f3
target/arm: Make FAULTMASK register banked for v8M
Make the FAULTMASK register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of FAULTMASK to
be restricted).

This patch includes the code to determine for v8M which copy
of FAULTMASK should be updated on exception exit; further
changes will be required to the exception exit code in general
to support v8M, so this is just a small piece of that.

The v8M ARM ARM introduces a notation where individual paragraphs
are labelled with R (for rule) or I (for information) followed
by a random group of subscript letters. In comments where we want
to refer to a particular part of the manual we use this convention,
which should be more stable across document revisions than using
section or page numbers.

Backports commit 42a6686b2f6199d086a58edd7731faeb2dbe7c14 from qemu
2018-03-04 20:58:38 -05:00
Peter Maydell ff3f7811ce
target/arm: Make PRIMASK register banked for v8M
Make the PRIMASK register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of PRIMASK to
be restricted).

Backports commit 6d8048341995b31a77dc2e0dcaaf4e3df0e3121a from qemu
2018-03-04 20:55:49 -05:00
Peter Maydell c9a7aad4dc
target/arm: Make BASEPRI register banked for v8M
Make the BASEPRI register banked if v8M security extensions are enabled.

Note that we do not yet implement the functionality of the new
AIRCR.PRIS bit (which allows the effect of the NS copy of BASEPRI to
be restricted).

Backports commit acf949411ffb675edbfb707e235800b02e6a36f8 from qemu
2018-03-04 20:54:44 -05:00
Peter Maydell f4d155ad3a
target/arm: Add MMU indexes for secure v8M
Now that MPU lookups can return different results for v8M
when the CPU is in secure vs non-secure state, we need to
have separate MMU indexes; add the secure counterparts
to the existing three M profile MMU indexes.

Backports commit 66787c7868d05d29974e09201611b718c976f955 from qemu
2018-03-04 20:53:04 -05:00
Peter Maydell 13bad2c234
target/arm: Register second AddressSpace for secure v8M CPUs
If a v8M CPU supports the security extension then we need to
give it two AddressSpaces, the same way we do already for
an A profile core with EL3.

Backports commit 1d2091bc75ab7f9e2c43082f361a528a63c79527 from qemu
2018-03-04 20:51:00 -05:00
Peter Maydell 8ce42ad30c
target/arm: Add state field, feature bit and migration for v8M secure state
As the first step in implementing ARM v8M's security extension:
* add a new feature bit ARM_FEATURE_M_SECURITY
* add the CPU state field that indicates whether the CPU is
currently in the secure state
* add a migration subsection for this new state
(we will add the Secure copies of banked register state
to this subsection in later patches)
* add a #define for the one new-in-v8M exception type
* make the CPU debug log print S/NS status

Backports commit 1e577cc7cffd3de14dbd321de5c3ef191c6ab07f from qemu
2018-03-04 20:50:04 -05:00
Peter Maydell 829a34ec55
target/arm: Implement new PMSAv8 behaviour
Implement the behavioural side of the new PMSAv8 specification.

Backports commit 504e3cc36b68b34c176f3f4116b1d5677471ec20 from qemu
2018-03-04 20:47:54 -05:00
Peter Maydell 1acd9efdc2
target/arm: Implement ARMv8M's PMSAv8 registers
As part of ARMv8M, we need to add support for the PMSAv8 MPU
architecture.

PMSAv8 differs from PMSAv7 both in register/data layout (for instance
using base and limit registers rather than base and size) and also in
behaviour (for example it does not have subregions); rather than
trying to wedge it into the existing PMSAv7 code and data structures,
we define separate ones.

This commit adds the data structures which hold the state for a
PMSAv8 MPU and the register interface to it. The implementation of
the MPU behaviour will be added in a subsequent commit.

Backports commit 0e1a46bbd2d6c39614b87f4e88ea305acce8a35f from qemu
2018-03-04 20:45:49 -05:00
Richard Henderson 6d2bcf6ed8
target/arm: Perform per-insn cross-page check only for Thumb
ARM is a fixed-length ISA and we can compute the page crossing
condition exactly once during init_disas_context.

Backports commit d0264d86b026e9d948de577b05ff86d708658576 from qemu
2018-03-04 20:42:22 -05:00
Richard Henderson ab21785d3f
target/arm: Split out thumb_tr_translate_insn
We need not check for ARM vs Thumb state in order to dispatch
disassembly of every instruction.

Backports commit 722ef0a562a8cd810297b00516e36380e2f33353 from qemu
2018-03-04 20:41:07 -05:00
Richard Henderson 23d769c856
target/arm: Move ss check to init_disas_context
We can check for single-step just once.

Backports commit f7708456aac23a8bb8864b12bcf1f20c6e4b7045 from qemu
2018-03-04 20:34:33 -05:00
Richard Henderson dd36ec2bbf
target/arm: [a64] Move page and ss checks to init_disas_context
Since AArch64 uses a fixed-width ISA, we can pre-compute the number of
insns remaining on the page. Also, we can check for single-step once.

Backports commit dcc3a21209a8eeae0fe43966012f8e08d3566f98 from qemu
2018-03-04 20:32:45 -05:00
Lluís Vilanova 74d437827b
target/arm: [tcg] Port to generic translation framework
Backports commit 2316922420da6fd0d1ffb5557d0cdcc5958bcf44 from qemu
2018-03-04 20:28:06 -05:00
Lluís Vilanova cc00feb2df
target/arm: [tcg,a64] Port to disas_log
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 58350fa4b2852fede96cfebad0b26bf79bca419c from qemu
2018-03-04 20:09:39 -05:00
Lluís Vilanova 5d3ff533a1
target/arm: [tcg] Port to disas_log
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 4013f7fc811e90b89da3a516dc71b01ca0e7e54e from qemu
2018-03-04 20:05:16 -05:00
Lluís Vilanova 7a02cb360c
target/arm: [tcg,a64] Port to tb_stop
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit be4079641f1bc755fc5d3ff194cf505c506227d8 from qemu
2018-03-04 20:02:45 -05:00
Lluís Vilanova d8def0cdb5
target/arm: [tcg] Port to tb_stop
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 70d3c035ae36a2c5c0f991ba958526127c92bb67 from qemu
2018-03-04 20:02:32 -05:00
Lluís Vilanova 665192d96f
target/arm: [tcg,a64] Port to translate_insn
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 24299c892cbfe29120f051b6b7d0bcf3e0cc8e85 from qemu
2018-03-04 19:47:54 -05:00
Lluís Vilanova 0c4909738d
target/arm: [tcg] Port to translate_insn
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 13189a9080b35b13af23f2be4806fa0cdbb31af3 from qemu
2018-03-04 19:44:01 -05:00
Lluís Vilanova 7b89c4c813
target/arm: [tcg,a64] Port to breakpoint_check
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 0cb56b373da70047979b61b042f59aaff4012e1b from qemu
2018-03-04 19:34:06 -05:00
Lluís Vilanova 67e0d99080
target/arm: [tcg,a64] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit a68956ad7f8510bdc0b54793c65c62c6a94570a4 from qemu
2018-03-04 19:31:22 -05:00
Lluís Vilanova b9df4e0ca0
target/arm: [tcg] Port to insn_start
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit f62bd897e64c6fb1f93e8795e835980516fe53b5 from qemu
2018-03-04 19:25:29 -05:00
Lluís Vilanova b3878f117e
target/arm: [tcg] Port to tb_start
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit b14768544fd715a3f1742c10fc36ae81c703cbc1 from qemu
2018-03-04 19:22:20 -05:00
Lluís Vilanova 529c6c17f1
target/arm: [tcg,a64] Port to init_disas_context
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 5c03990665aa9095e4d2734c8ca0f936a8e8f000 from qemu
2018-03-04 19:17:09 -05:00
Lluís Vilanova 5e5c722359
target/arm: [tcg] Port to init_disas_context
Incrementally paves the way towards using the generic instruction translation
loop.

Backports commit 1d8a5535238fc5976e0542a413f4ad88f5d4b233 from qemu
2018-03-04 19:10:55 -05:00
Lluís Vilanova 8581e6f6fe
target/arm: [tcg] Port to DisasContextBase
Incrementally paves the way towards using the generic
instruction translation loop.

Backports commit dcba3a8d443842f7a30a2c52d50a6b50b6982b35 from qemu
2018-03-04 19:00:06 -05:00
Paolo Bonzini 6997a5a090
gen-icount: check cflags instead of use_icount global
Backports commit cd42d5b23691ad73edfd6dbcfc935a960a9c5a65 from qemu
2018-03-04 14:26:26 -05:00
Richard Henderson cbb20881a2
target/arm: Delay check for magic kernel page
There's nothing magic about the exception that we generate in order
to execute the magic kernel page. We can and should allow gdb to
set a breakpoint at this location.

Backports commit 3805c2eba8999049bbbea29fdcdea4d47d943c88 from qemu
2018-03-04 14:09:09 -05:00
Lluís Vilanova 3a196c62ae
target: [tcg] Use a generic enum for DISAS_ values
Used later. An enum makes expected values explicit and
bounds the value space of switches.

Backports commit 77fc6f5e28667634916f114ae04c6029cd7b9c45 from qemu
2018-03-04 14:08:43 -05:00
Richard Henderson 4a5b1aec34
target/arm: Use DISAS_NORETURN
Fold DISAS_EXC and DISAS_TB_JUMP into DISAS_NORETURN.

In both cases all following code is dead. In the first
case because we have exited the TB via exception; in the
second case because we have exited the TB via goto_tb
and its associated machinery.

Backports commit a0c231e651b249960906f250b8e5eef5ed9888c4 from qemu
2018-03-04 13:57:18 -05:00
Peter Maydell b9f06be41d
target/arm: Allow deliver_fault() caller to specify EA bit
For external aborts, we will want to be able to specify the EA
(external abort type) bit in the syndrome field. Allow callers of
deliver_fault() to do that by adding a field to ARMMMUFaultInfo which
we use when constructing the syndrome values.

Backports commit c528af7aa64f159eb30b46e567b650c5440fc117 from qemu
2018-03-04 13:20:23 -05:00
Peter Maydell 320655293a
target/arm: Factor out fault delivery code
We currently have some similar code in tlb_fill() and in
arm_cpu_do_unaligned_access() for delivering a data abort or prefetch
abort. We're also going to want to do the same thing to handle
external aborts. Factor out the common code into a new function
deliver_fault().

Backports commit aac43da1d772a50778ab1252c13c08c2eb31fb39 from qemu
2018-03-04 13:18:31 -05:00
Peter Maydell 06619904c6
target/arm: Create and use new function arm_v7m_is_handler_mode()
Add a utility function for testing whether the CPU is in Handler
mode; this is just a check whether v7m.exception is non-zero, but
we do it in several places and it makes the code a bit easier
to read to not have to mentally figure out what the test is testing.

Backports commit 15b3f556bab4f961bf92141eb8521c8da3df5eb2 from qemu
2018-03-04 13:06:45 -05:00
Peter Maydell a897ee919b
target-arm: v7M: ignore writes to CONTROL.SPSEL from Thread mode
For v7M, writes to the CONTROL register are only permitted for
privileged code. However even if the code is privileged, the
write must not affect the SPSEL bit in the CONTROL register
if the CPU is in Thread mode (as documented in the pseudocode
for the MSR instruction). Implement this, instead of permitting
SPSEL to be written in all cases.

This was causing mbed applications not to run, because the
RTX RTOS they use relies on this behaviour.

Backports commit 792dac309c8660306557ba058b8b5a6a75ab3c1f from qemu
2018-03-04 13:04:20 -05:00
Peter Maydell 4ae080e27f
target/arm: Don't calculate lr in arm_v7m_cpu_do_interrupt() until needed
Move the code in arm_v7m_cpu_do_interrupt() that calculates the
magic LR value down to when we're actually going to use it.
Having the calculation and use so far apart makes the code
a little harder to understand than it needs to be.

Backports commit bd70b29ba92e4446f9e4eb8b9acc19ef6ff4a4d5 from qemu
2018-03-04 12:59:38 -05:00
Peter Maydell 75f8224d13
target/arm: Make arm_cpu_dump_state() handle the M-profile XPSR
Make the arm_cpu_dump_state() debug logging handle the M-profile XPSR
rather than assuming it's an A-profile CPSR. On M profile the PSR
line of a register dump will now look like this:

XPSR=41000000 -Z-- T priv-thread

Backports commit 5b906f3589443a3c69d8feeaac37263843ecfb8d from qemu
2018-03-04 12:58:56 -05:00
Peter Maydell 9056a93c9a
target/arm: Don't store M profile PRIMASK and FAULTMASK in daif
We currently store the M profile CPU register state PRIMASK and
FAULTMASK in the daif field of the CPU state in its I and F
bits. This is a legacy from the original implementation, which
tried to share the cpu_exec_interrupt code between A profile
and M profile. We've since separated out the two cases because
they are significantly different, so now there is no common
code between M and A profile which looks at env->daif: all the
uses are either in A-only or M-only code paths. Sharing the state
fields now is just confusing, and will make things awkward
when we implement v8M, where the PRIMASK and FAULTMASK
registers are banked between security states.

Switch M profile over to using v7m.faultmask and v7m.primask
fields for these registers.

Backports commit e6ae5981ea4b0f6feb223009a5108582e7644f8f from qemu
2018-03-04 12:56:29 -05:00
Peter Maydell 5d6b031550
target/arm: Define and use XPSR bit masks
The M profile XPSR is almost the same format as the A profile CPSR,
but not quite. Define some XPSR_* macros and use them where we
definitely dealing with an XPSR rather than reusing the CPSR ones.

Backports commit 987ab45e108953c1c98126c338c2119c243c372b from qemu
2018-03-04 12:54:41 -05:00
Peter Maydell 64c6727e4a
target/arm: Fix outdated comment about exception exit
When we switched our handling of exception exit to detect
the magic addresses at translate time rather than via
a do_unassigned_access hook, we forgot to update a
comment; correct the omission.

Backports commit 9d17da4b68a05fc78daa47f0f3d914eea5d802ea from qemu
2018-03-04 12:52:34 -05:00
Peter Maydell 219b3e8a08
target/arm: Remove incorrect comment about MPU_CTRL
Remove the comment that claims that some MPU_CTRL bits are stored
in sctlr_el[1]. This has never been true since MPU_CTRL was added
in commit 29c483a50607 -- the comment is a leftover from
Michael Davidsaver's original implementation, which I modified
not to use sctlr_el[1]; I forgot to delete the comment then.

Backports commit 59e4972c3fc63d981e8b613ebb3bb01a05848075 from qemu
2018-03-04 12:52:02 -05:00
Peter Maydell 108cff5e61
target/arm: Tighten up Thumb decode where new v8M insns will be
Tighten up the T32 decoder in the places where new v8M instructions
will be:
* TT/TTT/TTA/TTAT are in what was nominally LDREX/STREX r15, ...
which is UNPREDICTABLE:
make the UNPREDICTABLE behaviour be to UNDEF
* BXNS/BLXNS are distinguished from BX/BLX via the low 3 bits,
which in previous architectural versions are SBZ:
enforce the SBZ via UNDEF rather than ignoring it, and move
the "ARCH(5)" UNDEF case up so we don't leak a TCG temporary
* SG is in the encoding which would be LDRD/STRD with rn = r15;
this is UNPREDICTABLE and we currently UNDEF:
move this check further up the code so that we don't leak
TCG temporaries in the UNDEF case and have a better place
to put the SG decode.

This means that if a v8M binary is accidentally run on v7M
or if a test case hits something that we haven't implemented
yet the behaviour will be obvious (UNDEF) rather than obscure
(plough on treating it as a different instruction).

In the process, add some comments about the instruction patterns
at these points in the decode. Our Thumb and ARM decoders are
very difficult to understand currently, but gradually adding
comments like this should help to clarify what exactly has
been decoded when.

Backports commit ebfe27c593e5b222aa2a1fc545b447be3d995faa from qemu
2018-03-04 12:51:08 -05:00
Peter Maydell 6f4afe1a13
target/arm: Consolidate PMSA handling in get_phys_addr()
Currently get_phys_addr() has PMSAv7 handling before the
"is translation disabled?" check, and then PMSAv5 after it.
Tidy this up by making the PMSAv5 code handle the "MPU disabled"
case itself, so that we have all the PMSA code in one place.
This will make adding the PMSAv8 code slightly cleaner, and
also means that pre-v7 PMSA cores benefit from the MPU lookup
logging that the PMSAv7 codepath had.

Backports commit 3279adb95e34dd3d67c66d729458f7784747cf8d from qemu
2018-03-04 12:48:22 -05:00
Peter Maydell f85f301316
target/arm: Don't trap WFI/WFE for M profile
M profile cores can never trap on WFI or WFE instructions. Check for
M profile in check_wfx_trap() to ensure this.

The existing code will do the right thing for v7M cores because
the hcr_el2 and scr_el3 registers will be all-zeroes and so we
won't attempt to trap, but when we start setting ARM_FEATURE_V8
for v8M cores the v8A handling of SCTLR.nTWE and .nTWI will not
give the right results.

Backports commit 0e2845689ebdb4ea7174f96f6797e2d8942bd114 from qemu
2018-03-04 12:46:37 -05:00
Peter Maydell 2c9a196efe
target/arm: Use MMUAccessType enum rather than int
In the ARM get_phys_addr() code, switch to using the MMUAccessType
enum and its MMU_* values rather than int and literal 0/1/2.

Backports commit 03ae85f858fc46495258a5dd4551fff2c34bd495 from qemu
2018-03-04 12:45:56 -05:00
Alistair Francis 5d742aad0b
target/arm: Require alignment for load exclusive
According to the ARM ARM exclusive loads require the same alignment as
exclusive stores. Let's update the memops used for the load to match
that of the store. This adds the alignment requirement to the memops.

Backports commit 4a2fdb78e794c1ad93aa9e160235d6a61a2125de from qemu
2018-03-04 01:53:04 -05:00
Richard Henderson 4a8f556c29
target/arm: Correct load exclusive pair atomicity
We are not providing the required single-copy atomic semantics for
the 64-bit operation that is the 32-bit paired load.

At the same time, leave the entire 64-bit value in cpu_exclusive_val
and stop writing to cpu_exclusive_high. This means that we do not
have to re-assemble the 64-bit quantity when it comes time to store.

At the same time, drop a redundant temporary and perform all loads
directly into the cpu_exclusive_* globals.

Backports commit 19514cde3b92938df750acaecf2caaa85e1d36a6 from qemu
2018-03-04 01:49:35 -05:00
Alistair Francis 009a52dd13
target/arm: Correct exclusive store cmpxchg memop mask
When we perform the atomic_cmpxchg operation we want to perform the
operation on a pair of 32-bit registers. Previously we were just passing
the register size in which was set to MO_32. This would result in the
high register to be ignored. To fix this issue we hardcode the size to
be 64-bits long when operating on 32-bit pairs.

Backports commit 955fd0ad5d610f62ba2f4ce46a872bf50434dcf8 from qemu
2018-03-04 01:43:55 -05:00
Peter Maydell d72175d671
target/arm: Move PMSAv7 reset into arm_cpu_reset() so M profile MPUs get reset
When the PMSAv7 implementation was originally added it was for R profile
CPUs only, and reset was handled using the cpreg .resetfn hooks.
Unfortunately for M profile cores this doesn't work, because they do
not register any cpregs. Move the reset handling into arm_cpu_reset(),
where it will work for both R profile and M profile cores.

Backports commit 69ceea64bf565559a2b865ffb2a097d2caab805b from qemu
2018-03-04 01:20:57 -05:00
Peter Maydell 6add2f0f65
target/arm: Rename cp15.c6_rgnr to pmsav7.rnr
Almost all of the PMSAv7 state is in the pmsav7 substruct of
the ARM CPU state structure. The exception is the region
number register, which is in cp15.c6_rgnr. This exception
is a bit odd for M profile, which otherwise generally does
not store state in the cp15 substruct.

Rename cp15.c6_rgnr to pmsav7.rnr accordingly.

Backports commit 8531eb4f614a60e6582d4832b15eee09f7d27874 from qemu
2018-03-04 01:18:53 -05:00
Peter Maydell 266885f50f
target/arm: Don't allow guest to make System space executable for M profile
For an M profile v7PMSA, the system space (0xe0000000 - 0xffffffff) can
never be executable, even if the guest tries to set the MPU registers
up that way. Enforce this restriction.

Backports commit bf446a11dfb17ae7d8ed2b61a2444804eb458075 from qemu
2018-03-04 01:17:01 -05:00
Peter Maydell 34b9740081
target/arm: Don't do MPU lookups for addresses in M profile PPB region
The M profile PMSAv7 specification says that if the address being looked
up is in the PPB region (0xe0000000 - 0xe00fffff) then we do not use
the MPU regions but always use the default memory map. Implement this
(we were previously behaving like an R profile PMSAv7, which does not
special case this).

Backports commit 38aaa60ca464b48e6feef346709e97335d01b289 from qemu
2018-03-04 01:14:22 -05:00
Peter Maydell 4dc69f4b26
target/arm: Correct MPU trace handling of write vs execute
Correct off-by-one bug in the PSMAv7 MPU tracing where it would print
a write access as "reading", an insn fetch as "writing", and a read
access as "execute".

Since we have an MMUAccessType enum now, we can make the code clearer
in the process by using that rather than the raw 0/1/2 values.

Backports commit 709e4407add7acacc593cb6cdac026558c9a8fb6 from qemu
2018-03-04 01:13:19 -05:00
Lluís Vilanova 32b3c3815d
tcg: Pass generic CPUState to gen_intermediate_code()
Needed to implement a target-agnostic gen_intermediate_code()
in the future.

Backports commit 9c489ea6bed134fecfd556b439c68bba48fbe102 from qemu
2018-03-03 23:34:18 -05:00
Alex Bennée 0bd8dc4e0a
target/arm: use DISAS_EXIT for eret handling
Previously DISAS_JUMP did ensure this but with the optimisation of
8a6b28c7 (optimize indirect branches) we might not leave the loop.
This means if any pending interrupts are cleared by changing IRQ flags
we might never get around to servicing them. You usually notice this
by seeing the lookup_tb_ptr() helper gainfully chaining TBs together
while cpu->interrupt_request remains high and the exit_request has not
been set.

This breaks amongst other things the OPTEE test suite which executes
an eret from the secure world after a non-secure world IRQ has gone
pending which then never gets serviced.

Instead of using the previously implied semantics of DISAS_JUMP we use
DISAS_EXIT which will always exit the run-loop.

Backports commit b29fd33db578decacd14f34933b29aece3e7c25e from qemu
2018-03-03 22:43:16 -05:00
Alex Bennée 65356210a8
target/arm: use gen_goto_tb for ISB handling
While an ISB will ensure any raised IRQs happen on the next
instruction it doesn't cause any to get raised by itself. We can
therefore use a simple tb exit for ISB instructions and rely on the
exit_request check at the top of each TB to deal with exiting if
needed.

Backports commit 0b609cc128ba5ef16cc841bcade898d1898f1dc3 from qemu
2018-03-03 22:42:33 -05:00
Alex Bennée 0f8d216d67
target/arm/translate: ensure gen_goto_tb sets exit flags
As the gen_goto_tb function can do both static and dynamic jumps it
should also set the is_jmp field. This matches the behaviour of the
a64 code.

Backports commit 4cae8f56fbab2798586576a56cc669f0127d04fb from qemu
2018-03-03 22:38:12 -05:00
Alex Bennée bffa25cc07
target/arm/translate.h: expand comment on DISAS_EXIT
We already have an exit condition, DISAS_UPDATE which will exit the
run-loop. Expand on the difference with DISAS_EXIT in the comments

Backports commit abd1fb0ee2c58b99f4b2d15718f1825fe4984e12 from qemu
2018-03-03 22:38:11 -05:00
Alex Bennée 63d40e1a55
target/arm/translate: make DISAS_UPDATE match declared semantics
DISAS_UPDATE should be used when the wider CPU state other than just
the PC has been updated and we should therefore exit the TCG runtime
and return to the main execution loop rather assuming DISAS_JUMP would
do that.

Backports commit e8d5230221851e8933811f1579fd13371f576955 from qemu
2018-03-03 22:38:07 -05:00