Commit graph

239 commits

Author SHA1 Message Date
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
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
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 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
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
Lioncash 9a2581aff6
Comment out tailchaining code
Allows build to continue.
2018-08-16 07:11:31 -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 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
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
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
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 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
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
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 a9160a0e08
target/arm: Implement SVE floating-point convert to integer
Backports commit df4de1affc440d6f2cdaeea329b90c0b88ece5a1 from qemu
2018-07-03 04:02:58 -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
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 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
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
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 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
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
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 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
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
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
Eduardo Habkost 074865ff98
cpu: Generify CPU init functions
Backports commits 2994fd96d986578a342f2342501b4ad30f6d0a85,
701e3c78ce45fa630ffc6826c4b9a4218954bc7f, and
d1853231c60d16af78cf4d1608d043614bfbac0b from qemuu
2018-03-20 08:21:51 -04:00
Lioncash c93c3bd4b3
target/arm/helper: Correct bad merge 2018-03-12 11:33:45 -04:00
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 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 7161c1ed52
arm/translate-a64: add FP16 SCVTF/UCVFT to simd_two_reg_misc_fp16 2018-03-08 18:48:25 -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
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
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
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
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 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
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
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
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 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 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 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