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86 commits

Author SHA1 Message Date
Richard Henderson e6196b2040
target/arm: Add PAuth helpers
The cryptographic internals are stubbed out for now,
but the enable and trap bits are checked.

Backports commit 0d43e1a2d29a05f7b0d5629caaff18733cbdf3bb from qemu
2019-01-22 15:27:15 -05:00
Richard Henderson 1f7d228c8a
target/arm: Introduce raise_exception_ra
This path uses cpu_loop_exit_restore to unwind current processor state.

Backports commit 7469f6c696d74ad3b22b67c08e1e8f79e2b5d3d6 from qemu
2019-01-22 15:20:06 -05:00
Peter Maydell 8b69824de7
target/arm: Move id_aa64mmfr* to ARMISARegisters
At the same time, define the fields for these registers,
and use those defines in arm_pamax().

Backports commit 3dc91ddbc68391f934bf6945853e99cf6810fc00 from qemu
2018-12-18 04:03:50 -05:00
Peter Maydell 61c0f40ac3
target/arm: Hyp mode R14 is shared with User and System
Hyp mode is an exception to the general rule that each AArch32
mode has its own r13, r14 and SPSR -- it has a banked r13 and
SPSR but shares its r14 with User and System mode. We were
incorrectly implementing it as banked, which meant that on
entry to Hyp mode r14 was 0 rather than the USR/SYS r14.

We provide a new function r14_bank_number() which is like
the existing bank_number() but provides the index into
env->banked_r14[]; bank_number() provides the index to use
for env->banked_r13[] and env->banked_cpsr[].

All the points in the code that were using bank_number()
to index into env->banked_r14[] are updated for consintency:
* switch_mode() -- this is the only place where we fix
an actual bug
* aarch64_sync_32_to_64() and aarch64_sync_64_to_32():
no behavioural change as we already special-cased Hyp R14
* kvm32.c: no behavioural change since the guest can't ever
be in Hyp mode, but conceptually the right thing to do
* msr_banked()/mrs_banked(): we can never get to the case
that accesses banked_r14[] with tgtmode == ARM_CPU_MODE_HYP,
so no behavioural change

Backports commit 593cfa2b637b92d37eef949653840dc065cdb960 from qemu
2018-11-16 21:58:29 -05:00
Peter Maydell 92bf8ee620
target/arm: Correctly implement handling of HCR_EL2.{VI, VF}
In commit 8a0fc3a29fc2315325400 we tried to implement HCR_EL2.{VI,VF},
but we got it wrong and had to revert it.

In that commit we implemented them as simply tracking whether there
is a pending virtual IRQ or virtual FIQ. This is not correct -- these
bits cause a software-generated VIRQ/VFIQ, which is distinct from
whether there is a hardware-generated VIRQ/VFIQ caused by the
external interrupt controller. So we need to track separately
the HCR_EL2 bit state and the external virq/vfiq line state, and
OR the two together to get the actual pending VIRQ/VFIQ state.

Fixes: 8a0fc3a29fc2315325400c738f807d0d4ae0ab7f

Backports commit 89430fc6f80a5aef1d4cbd6fc26b40c30793786c from qemu
2018-11-16 21:53:53 -05:00
Peter Maydell d60fe610bb
target/arm: Report correct syndrome for FP/SIMD traps to Hyp mode
For traps of FP/SIMD instructions to AArch32 Hyp mode, the syndrome
provided in HSR has more information than is reported to AArch64.
Specifically, there are extra fields TA and coproc which indicate
whether the trapped instruction was FP or SIMD. Add this extra
information to the syndromes we construct, and mask it out when
taking the exception to AArch64.

Backports commit 4be42f4013fa1a9df47b48aae5148767bed8e80c from qemu
2018-11-10 09:36:41 -05:00
Peter Maydell 075bac4d57
target/arm: Get IL bit correct for v7 syndrome values
For the v7 version of the Arm architecture, the IL bit in
syndrome register values where the field is not valid was
defined to be UNK/SBZP. In v8 this is RES1, which is what
QEMU currently implements. Handle the desired v7 behaviour
by squashing the IL bit for the affected cases:
* EC == EC_UNCATEGORIZED
* prefetch aborts
* data aborts where ISV is 0

(The fourth case listed in the v8 Arm ARM DDI 0487C.a in
section G7.2.70, "illegal state exception", can't happen
on a v7 CPU.)

This deals with a corner case noted in a comment.

Backports commit 2ed08180db096ea5e44573529b85e09b1ed10b08 from qemu
2018-11-10 09:29:13 -05:00
Peter Maydell 99516b43a3
target/arm: New utility function to extract EC from syndrome
Create and use a utility function to extract the EC field
from a syndrome, rather than open-coding the shift.

Backports commit 64b91e3f890a8c221b65c6820a5ee39107ee40f5 from qemu
2018-11-10 09:28:23 -05:00
Lioncash a0358202a7
target/arm: Improve debug logging of AArch32 exception return
For AArch32, exception return happens through certain kinds
of CPSR write. We don't currently have any CPU_LOG_INT logging
of these events (unlike AArch64, where we log in the ERET
instruction). Add some suitable logging.

This will log exception returns like this:
Exception return from AArch32 hyp to usr PC 0x80100374

paralleling the existing logging in the exception_return
helper for AArch64 exception returns:
Exception return from AArch64 EL2 to AArch64 EL0 PC 0x8003045c
Exception return from AArch64 EL2 to AArch32 EL0 PC 0x8003045c

(Note that an AArch32 exception return can only be
AArch32->AArch32, never to AArch64.)

Backports commit 81e3728407bf4a12f83e14fd410d5f0a7d29b5b4 from qemu
2018-11-10 09:09:52 -05:00
Lioncash cb935d868e
target/arm: Add v8M stack limit checks on NS function calls 2018-10-08 14:15:15 -04:00
Peter Maydell ca5d7b8fd2
target/arm: Add v8M stack checks on ADD/SUB/MOV of SP
Add code to insert calls to a helper function to do the stack
limit checking when we handle these forms of instruction
that write to SP:
* ADD (SP plus immediate)
* ADD (SP plus register)
* SUB (SP minus immediate)
* SUB (SP minus register)
* MOV (register)

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

Backports commit 5529bf188d996391ff52a0e1801daf9c6a6bfcb0 from qemu
2018-10-08 14:15:15 -04:00
Richard Henderson 66ffb372e7
target/arm: Pass TCGMemOpIdx to sve memory helpers
There is quite a lot of code required to compute cpu_mem_index,
or even put together the full TCGMemOpIdx. This can easily be
done at translation time.

Backports commit 500d04843ba953dc4560e44f04001efec38c14a6 from qemu
2018-10-08 14:15:15 -04:00
Aaron Lindsay 99a0be89a8
target/arm: Add pre-EL change hooks
Because the design of the PMU requires that the counter values be
converted between their delta and guest-visible forms for mode
filtering, an additional hook which occurs before the EL is changed is
necessary.

Backports commit b5c53d1b3886387874f8c8582b205aeb3e4c3df6 from qemu
2018-04-26 09:21:54 -04:00
Aaron Lindsay 8caf217d26
target/arm: Support multiple EL change hooks
Backports commit 08267487c99e8150382420936ab72c1e0ad74ce3 from qemu
2018-04-26 09:16:09 -04:00
Peter Maydell 16c0c2d253
target/arm: Factor out code to calculate FSR for debug exceptions
When a debug exception is taken to AArch32, it appears as a Prefetch
Abort, and the Instruction Fault Status Register (IFSR) must be set.
The IFSR has two possible formats, depending on whether LPAE is in
use. Factor out the code in arm_debug_excp_handler() which picks
an FSR value into its own utility function, update it to use
arm_fi_to_lfsc() and arm_fi_to_sfsc() rather than hard-coded constants,
and use the correct condition to select long or short format.

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

Backports commit 81621d9ab8a0f07956e67850b15eebf6d6992eec from qemu
2018-03-25 16:35:27 -04:00
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
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
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 211cbde764
target/arm: Provide fault type enum and FSR conversion functions
Currently get_phys_addr() and its various subfunctions return
a hard-coded fault status register value for translation
failures. This is awkward because FSR values these days may
be either long-descriptor format or short-descriptor format.
Worse, the right FSR type to use doesn't depend only on the
translation table being walked -- some cases, like fault
info reported to AArch32 EL2 for some kinds of ATS operation,
must be in long-descriptor format even if the translation
table being walked was short format. We can't get those cases
right with our current approach.

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

Backports commit 1fa498fe0de979030bd1f481046e9f1c5574a584 from qemu
2018-03-05 13:48:32 -05:00
Peter Maydell 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
Stefano Stabellini 1212c9b73c
fix WFI/WFE length in syndrome register
WFI/E are often, but not always, 4 bytes long. When they are, we need to
set ARM_EL_IL_SHIFT in the syndrome register.

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

Set dc->insn in both arm_tr_translate_insn and thumb_tr_translate_insn.

Backports commit 58803318e5a546b2eb0efd7a053ed36b6c29ae6f from qemu
2018-03-05 11:21:51 -05:00
Peter Maydell ee9b8a20c9
target/arm: Implement secure function return
Secure function return happens when a non-secure function has been
called using BLXNS and so has a particular magic LR value (either
0xfefffffe or 0xfeffffff). The function return via BX behaves
specially when the new PC value is this magic value, in the same
way that exception returns are handled.

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

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

Backports commit 3e3fa230e3b8ffe119f14ba57a6bc677a411be57 from qemu
2018-03-05 03:31:59 -05:00
Peter Maydell 7988aec017
target/arm: Implement security attribute lookups for memory accesses
Implement the security attribute lookups for memory accesses
in the get_phys_addr() functions, causing these to generate
various kinds of SecureFault for bad accesses.

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

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

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

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

Backports commit 35337cc391245f251bfb9134f181c33e6375d6c1 from qemu
2018-03-05 01:57:07 -05:00
Peter Maydell 1301cb1771
target/arm: Add and use defines for EXCRET constants
The exception-return magic values get some new bits in v8M, which
makes some bit definitions for them worthwhile.

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

Backports commit 4d1e7a4745c050f7ccac49a1c01437526b5130b5 from qemu
2018-03-04 23:12:37 -05:00
Peter Maydell ceccd92940
target/arm: Clear exclusive monitor on v7M reset, exception entry/exit
For M profile we must clear the exclusive monitor on reset, exception
entry and exception exit. We weren't doing any of these things; fix
this bug.

Backports commit dc3c4c14f0f12854dbd967be3486f4db4e66d25b from qemu
2018-03-04 23:09:41 -05:00
Peter Maydell 2070ef1c37
boards.h: Define new flag ignore_memory_transaction_failures
Define a new MachineClass field ignore_memory_transaction_failures.
If this is flag is true then the CPU will ignore memory transaction
failures which should cause the CPU to take an exception due to an
access to an unassigned physical address; the transaction will
instead return zero (for a read) or be ignored (for a write). This
should be set only by legacy board models which rely on the old
RAZ/WI behaviour for handling devices that QEMU does not yet model.
New board models should instead use "unimplemented-device" for all
memory ranges where the guest will attempt to probe for a device that
QEMU doesn't implement and a stub device is required.

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

Backports commit ed860129acd3fcd0b1e47884e810212aaca4d21b from qemu
2018-03-04 21:27:15 -05:00
Peter Maydell 221232fb35
target/arm: Move regime_is_secure() to target/arm/internals.h
Move the regime_is_secure() utility function to internals.h;
we are going to want to call it from translate.c.

Backports commit 61fcd69b0db268e7612b07fadc436b93def91768 from qemu
2018-03-04 21:14:05 -05:00
Peter Maydell b9f06be41d
target/arm: Allow deliver_fault() caller to specify EA bit
For external aborts, we will want to be able to specify the EA
(external abort type) bit in the syndrome field. Allow callers of
deliver_fault() to do that by adding a field to ARMMMUFaultInfo which
we use when constructing the syndrome values.

Backports commit c528af7aa64f159eb30b46e567b650c5440fc117 from qemu
2018-03-04 13:20:23 -05:00
Peter Maydell 2c9a196efe
target/arm: Use MMUAccessType enum rather than int
In the ARM get_phys_addr() code, switch to using the MMUAccessType
enum and its MMU_* values rather than int and literal 0/1/2.

Backports commit 03ae85f858fc46495258a5dd4551fff2c34bd495 from qemu
2018-03-04 12:45:56 -05:00
Peter Maydell 1cf80d7536
arm: Move excnames[] array into arm_log_exceptions()
The excnames[] array is defined in internals.h because we used
to use it from two different source files for handling logging
of AArch32 and AArch64 exception entry. Refactoring means that
it's now used only in arm_log_exception() in helper.c, so move
the array into that function.

Backports commit 2c4a7cc5afb1bfc1728a39abd951ddd7714c476e from qemu
2018-03-02 14:39:37 -05:00
Peter Maydell 1af1944903
target/arm: Add missing entries to excnames[] for log strings
Recent changes have added new EXCP_ values to ARM but forgot
to update the excnames[] array which is used to provide
human-readable strings when printing information about the
exception for debug logging. Add the missing entries, and
add a comment to the list of #defines to help avoid the mistake
being repeated in future.

Backports commit 32b81e620ea562d56ab2733421b5da1082b237a2 from qemu
2018-03-02 14:38:23 -05:00
Michael Davidsaver 2769c6ada0
armv7m: Fix reads of CONTROL register bit 1
The v7m CONTROL register bit 1 is SPSEL, which indicates
the stack being used. We were storing this information
not in v7m.control but in the separate v7m.other_sp
structure field. Unfortunately, the code handling reads
of the CONTROL register didn't take account of this, and
so if SPSEL was updated by an exception entry or exit then
a subsequent guest read of CONTROL would get the wrong value.

Using a separate structure field doesn't really gain us
anything in efficiency, so drop this unnecessary complexity
in favour of simply storing all the bits in v7m.control.

This is a migration compatibility break for M profile
CPUs only.

Backports commit abc24d86cc0364f402e438fae3acb14289b40734 from qemu
2018-03-02 13:26:38 -05:00
Julian Brown cc217b0c90
arm: Correctly handle watchpoints for BE32 CPUs
In BE32 mode, sub-word size watchpoints can fail to trigger because the
address of the access is adjusted in the opcode helpers before being
compared with the watchpoint registers. This patch reverses the address
adjustment before performing the comparison with the help of a new CPUClass
hook.

This version of the patch augments and tidies up comments a little.

Backports commit 40612000599e52e792d23c998377a0fa429c4036 from qemu
2018-03-02 00:24:33 -05:00
Thomas Huth b2f1326437
Move target-* CPU file into a target/ folder
We've currently got 18 architectures in QEMU, and thus 18 target-xxx
folders in the root folder of the QEMU source tree. More architectures
(e.g. RISC-V, AVR) are likely to be included soon, too, so the main
folder of the QEMU sources slowly gets quite overcrowded with the
target-xxx folders.
To disburden the main folder a little bit, let's move the target-xxx
folders into a dedicated target/ folder, so that target-xxx/ simply
becomes target/xxx/ instead.

Backports commit fcf5ef2ab52c621a4617ebbef36bf43b4003f4c0 from qemu
2018-03-01 22:50:58 -05:00
Renamed from qemu/target-arm/internals.h (Browse further)