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
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
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
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
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
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
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
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
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
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
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
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
We were using the wrong flush-to-zero bit for the non-half input.
Fixes: 46d33d1e3c9
Backports commit e4ab5124a5c2e2291006b24bdc21c3dd8d087ff4 from qemu
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
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
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
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
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
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
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
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
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
The normal vector element is sign-extended before
comparing with the wide vector element.
Backports commit df4e001093988544d09887122ae824f18ba55c68 from qemu
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
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
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
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
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
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
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
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
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
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
'I' was being double-incremented; correctly within the inner loop
and incorrectly within the outer loop.
Backports commit 628fc75f3a3bb115de3b445c1a18547c44613cfe from qemu
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
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
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
There is no need to re-set these 3 features already
implied by the call to aarch64_a15_initfn.
Backports commit 0b33968e7f4cf998f678b2d1a5be3d6f3f3513d8 from qemu
There is no need to re-set these 9 features already
implied by the call to aarch64_a57_initfn.
Backports commit 156a7065365578deb3d63c2b5b69a4b5999a8fcc from qemu
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
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
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
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
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
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
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
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
Unlike ARMv7-M, ARMv6-M and ARMv8-M Baseline only supports naturally
aligned memory accesses for load/store instructions.
Backports commit 2aeba0d007d33efa12a6339bb140aa634e0d52eb from qemu
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
The arrays were made static, "if" was simplified because V7M and V8M
define V6 feature.
Backports commit 8297cb13e407db8a96cc7ed6b6a6c318a150759a from qemu
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
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
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
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
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
Excepting MOVPRFX, which isn't a reduction. Presumably it is
placed within the group because of its encoding.
Backports commit 047cec971d2791b206677b954227ea92ff7ee3db from qemu
These were the instructions that were stubbed out when
introducing the decode skeleton.
Backports commit 39eea56172e668cc4cca611ed9166779df54ac63 from qemu
Including only 4, as-yet unimplemented, instruction patterns
so that the whole thing compiles.
Backports commit 38388f7ee3adc04a7e7246c04352451c4f8d00fb from qemu
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
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
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
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
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
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
Use write_fp_dreg and clear_vec_high to zero the bits
that need zeroing for these cases.
Backports commit 9a9f1f59521f46e8ff4527d9a2b52f83577e2aa3 from qemu
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
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
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
This implements all of the v8.1-Atomics instructions except
for compare-and-swap, which is decoded elsewhere.
Backports commit 74608ea45434c9b07055b21885e093528c5ed98c from qemu
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
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
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
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
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
Path analysis shows that size == 3 && !is_q has been eliminated.
Fixes: Coverity CID1385853
Backports commit a8766e3172c1671cab297c1ef4566a3c5d094822 from qemu
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
This is a bug fix to ensure 64-bit reads of these registers don't read
adjacent data.
Backports commit e4e91a217c17fff4045dd4b423cdcb471b3d6a0e from qemu
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
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
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
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
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
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
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
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
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
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
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
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
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
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
cpu_init(cpu_model) were replaced by cpu_create(cpu_type) so
no users are left, remove it.
Backports commit 3f71e724e283233753f1b5b3d6a30948d3084636 from qemu
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
Backports commits 2994fd96d986578a342f2342501b4ad30f6d0a85,
701e3c78ce45fa630ffc6826c4b9a4218954bc7f, and
d1853231c60d16af78cf4d1608d043614bfbac0b from qemuu
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
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
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
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
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
Convert all machines to use DEFINE_MACHINE() instead of QEMUMachine
automatically using a script.
Backports commit e264d29de28c5b0be3d063307ce9fb613b427cc3 from qemu
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
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
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
This includes FMOV, FABS, FNEG, FSQRT and FRINT[NPMZAXI]. We re-use
existing helpers to achieve this.
Backports commit c2c08713a6a5846bbe601d4d1b4f9708ba77efdc from qemu
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
I only needed to do a little light re-factoring to support the
half-precision helpers.
Backports commit 5c36d89567cfd049a7c59ff219639f788225068f from qemu
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
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
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
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
This adds the full range of half-precision floating point to integral
instructions.
Backports commit 6109aea2d954891027acba64a13f1f1c7463cfac from qemu
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
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
The helpers use the new re-factored muladd support in SoftFloat for
the float16 work.
Backports commit 5d265064cf30daaacce5a4ce9945fc573015fb5f from qemu
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
Backports commit 2deb992b767d28035fac3b374c7730494ff0b43d from qemu
Also backports the fp16 changes introduced in commit f566c0474a9b9bbd9ed248607e4007e24d3358c0
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Handle possible MPU faults, SAU faults or bus errors when
popping register state off the stack during exception return.
Backports commit 95695effe8caa552b8f243bceb3a08de4003c882 from qemu
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Implement the TT instruction which queries the security
state and access permissions of a memory location.
Backports commit 5158de241b0fb344a6c948dfcbc4e611ab5fafbe from qemu
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Implement the SG instruction, which we emulate 'by hand' in the
exception handling code path.
Backports commit 333e10c51ef5876ced26f77b61b69ce0f83161a9 from qemu
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
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
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
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
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
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
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
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
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
Add the new M profile Secure Fault Status Register
and Secure Fault Address Register.
Backports commit bed079da04dd9e0e249b9bc22bca8dce58b67f40 from qemu
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
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
Make the MPU registers MPU_MAIR0 and MPU_MAIR1 banked if v8M security
extensions are enabled.
Backports commit 4125e6feb71c810ca38f0d8e66e748b472a9cc54 from qemu
