All the AArch32 ID registers are visible from AArch64
(in addition to the AArch64-specific ID_AA64* registers).
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
For ARMv8 there are two changes to the MVFR media feature registers:
* there is a new MVFR2 which is accessible from 32 bit code
* 64 bit code accesses these via the usual sysreg instructions
rather than with a floating-point specific instruction
Implement this.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement exception handling for AArch64 EL1. Exceptions from AArch64 or
AArch32 EL0 are supported.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: fixed minor style nits; updated to match changes in
previous patches; added some of the simpler cases of
illegal-exception-return support]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Move arm_log_exception() into internals.h so we can use it from
helper-a64.c for the AArch64 exception entry code.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the AArch64 SPSR_EL1. For compatibility with how KVM
handles SPSRs and with the architectural mapping between AArch32
and AArch64, we put this in the banked_spsr[] array in the slot
that is used for SVC in AArch32. This means we need to extend the
array from uint32_t to uint64_t, which requires some reworking
of the 32 bit KVM save/restore code.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement handling for the AArch64 SP_EL0 system register.
This holds the EL0 stack pointer, and is only accessible when
it's not being used as the stack pointer, ie when we're in EL1
and EL1 is using its own stack pointer. We also provide a
definition of the SP_EL1 register; this isn't guest visible
as a system register for an implementation like QEMU which
doesn't provide EL2 or EL3; however it is useful for ensuring
the underlying state is migrated.
We need to update the state fields in the CPU state whenever
we switch stack pointers; this happens when we take an exception
and also when SPSEL is used to change the bit in PSTATE which
indicates which stack pointer EL1 should use.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Add the AArch64 ELR_EL1 register.
Note that this does not live in env->cp15: for KVM migration
compatibility we need to migrate it separately rather than
as part of the system registers, because the KVM-to-userspace
interface puts it in the struct kvm_regs rather than making
them visible via the ONE_REG ioctls.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement AArch64 views of ESR_EL1 and FAR_EL1, and make the 32 bit
DFSR, DFAR, IFAR share state with them as architecturally specified.
The IFSR doesn't share state with any AArch64 register visible at EL1,
so just rename the state field without widening it to 64 bits.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: Minor tweaks; fix some bugs involving inconsistencies between
use of offsetof() or offsetoflow32() and struct field width]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The ARM946 model currently uses the c5_data and c5_insn fields in the CPU
state struct to store the contents of its access permission registers.
This is confusing and a good source of bugs because for all the MMU-based
CPUs those fields are fault status and fault address registers, which
behave completely differently; they just happen to use the same cpreg
encoding. Split them out to use their own fields instead.
These registers are only present in PMSAv5 MPU systems (of which the
ARM946 is our only current example); PMSAv6 and PMSAv7 (which we have
no implementations of) handle access permissions differently. We name
the new state fields accordingly.
Note that this change fixes a bug where a data abort or prefetch abort
on the ARM946 would accidentally corrupt the access permission registers
because the interrupt handling code assumed the c5_data and c5_insn
fields were always fault status registers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the DC ZVA instruction, which clears a block of memory.
The fast path obtains a pointer to the underlying RAM via the TCG TLB
data structure so we can do a direct memset(), with fallback to a
simple byte-store loop in the slow path.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Suppress the ID_AA64DFR0_EL1 PMUVer field, even if the CPU specific
value claims that it exists. QEMU doesn't currently implement it,
and not advertising it prevents the guest from trying to use it
and getting UNDEFs on unimplemented registers.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
---
This is arguably a hack, but otherwise Linux tries to prod
half a dozen PMU sysregs.
Add support for v8 page table walks. This supports stage 1 translations
for 4KB, 16KB and 64KB page sizes starting with 0 or 1 level.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: fix style nits, fold in 16/64K page support patch, use
arm_el_is_aa64() to decide whether to do 64 bit page table walk]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
The current A32/T32 decoder bases its "is VFP/Neon enabled?" check
on the FPSCR.EN bit. This is correct if EL1 is AArch32, but for
an AArch64 EL1 the logic is different: it must act as if FPSCR.EN
is always set. Instead, trapping must happen according to CPACR
bits for cp10/cp11; these cover all of FP/Neon, including the
FPSCR/FPSID/MVFR register accesses which FPSCR.EN does not affect.
Add support for CPACR checks (which are also required for ARMv7,
but were unimplemented because Linux happens not to use them)
and make sure they generate exceptions with the correct syndrome.
We actually return incorrect syndrome information for cases
where FP is disabled but the specific instruction bit pattern
is unallocated: strictly these should be the Uncategorized
exception, not a "SIMD disabled" exception. This should be
mostly harmless, and the structure of the A32/T32 VFP/Neon
decoder makes it painful to put the 'FP disabled?' checks in
the right places.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Because unallocated encodings generate different exception syndrome
information from traps due to FP being disabled, we can't do a single
"is fp access disabled" check at a high level in the decode tree.
To help in catching bugs where the access check was forgotten in some
code path, we set this flag when the access check is done, and assert
that it is set at the point where we actually touch the FP regs.
This requires us to pass the DisasContext to the vec_reg_offset
and fp_reg_offset functions.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
For the A64 instruction set, the only FP/Neon disable trap
is the CPACR FPEN bits, which may indicate "enabled", "disabled"
or "disabled for EL0". Add a bit to the AArch64 tb flags indicating
whether FP/Neon access is currently enabled and make the decoder
emit code to raise exceptions on use of FP/Neon insns if it is not.
We use a new flag in DisasContext rather than borrowing the
existing vfp_enabled flag because the A32/T32 decoder is going
to need both.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
---
I'm aware this is a rather hard to review patch; sorry.
I have done an exhaustive check that we have fp access checks
in all code paths with the aid of the assertions added in the
next patch plus the code-coverage hack patch I posted to the
list earlier.
This patch is correct as of
09e037354 target-arm: A64: Add saturating accumulate ops (USQADD/SUQADD)
which was the last of the Neon insns to be added, so assuming
no refactoring of the code it should be fine.
Set up the required syndrome information when we detect an MMU fault.
Signed-off-by: Rob Herring <rob.herring@linaro.org>
[PMM: split out from exception handling patch, tweaked to bring
in line with how we create other kinds of syndrome information]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Add new helpers exception_with_syndrome (for generating an exception
with syndrome information) and exception_uncategorized (for generating
an exception with "Unknown or Uncategorized Reason", which have a syndrome
register value of zero), and use them to generate the correct syndrome
information for exceptions which are raised directly from generated code.
This patch includes moving the A32/T32 gen_exception_insn functions
further up in the source file; they will be needed for "VFP/Neon disabled"
exception generation later.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
For exceptions taken to AArch64, if a coprocessor/system register
access fails due to a trap or enable bit then the syndrome information
must include details of the failing instruction (crn/crm/opc1/opc2
fields, etc). Make the decoder construct the syndrome information
at translate time so it can be passed at runtime to the access-check
helper function and used as required.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
For AArch32 exceptions, the only information provided about
the cause of an exception is the individual exception type (data
abort, undef, etc), which we store in cs->exception_index. For
AArch64, the CPU provides much more detail about the cause of
the exception, which can be found in the syndrome register.
Create a set of fields in CPUARMState which must be filled in
whenever an exception is raised, so that exception entry can
correctly fill in the syndrome register for the guest.
This includes the information which in AArch32 appears in
the DFAR and IFAR (fault address registers) and the DFSR
and IFSR (fault status registers) for data aborts and
prefetch aborts, since if we end up taking the MMU fault
to AArch64 rather than AArch32 this will need to end up
in different system registers.
This patch does a refactoring which moves the setting of the
AArch32 DFAR/DFSR/IFAR/IFSR from the point where the exception
is raised to the point where it is taken. (This is no change
for cores with an MMU, retains the existing clearly incorrect
behaviour for ARM946 of trashing the MP access permissions
registers which share the c5_data and c5_insn state fields,
and has no effect for v7M because we don't implement its
MPU fault status or address registers.)
As a side effect of the cleanup we fix a bug in the AArch64
linux-user mode code where we were passing a 64 bit fault
address through the 32 bit c6_data/c6_insn fields: it now
goes via the always-64-bit exception.vaddress.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Implement the DAIF system register which is a view of the
DAIF bits in PSTATE. To avoid needing a readfn, we widen
the daif field in CPUARMState to uint64_t.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Currently cpu.h defines a mixture of functions and types needed by
the rest of QEMU and those needed only by files within target-arm/.
Split the latter out into a new header so they aren't needlessly
exposed further than required.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
* remotes/rth/tcg-aarch-6-5: (25 commits)
tcg-aarch64: Use tcg_out_mov in preference to tcg_out_movr
tcg-aarch64: Prefer unsigned offsets before signed offsets for ldst
tcg-aarch64: Introduce tcg_out_insn_3312, _3310, _3313
tcg-aarch64: Merge aarch64_ldst_get_data/type into tcg_out_op
tcg-aarch64: Introduce tcg_out_insn_3507
tcg-aarch64: Support stores of zero
tcg-aarch64: Implement TCG_TARGET_HAS_new_ldst
tcg-aarch64: Pass qemu_ld/st arguments directly
tcg-aarch64: Use TCGMemOp in qemu_ld/st
tcg-aarch64: Use ADR to pass the return address to the ld/st helpers
tcg-aarch64: Use tcg_out_call for qemu_ld/st
tcg-aarch64: Avoid add with zero in tlb load
tcg-aarch64: Implement tcg_register_jit
tcg-aarch64: Introduce tcg_out_insn_3314
tcg-aarch64: Reuse LR in translated code
tcg-aarch64: Use CBZ and CBNZ
tcg-aarch64: Create tcg_out_brcond
tcg-aarch64: Use symbolic names for branches
tcg-aarch64: Use adrp in tcg_out_movi
tcg-aarch64: Special case small constants in tcg_out_movi
...
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Technically, these variables could have been referenced both via
offsets from env and as TCG registers, which would be illegal.
Of course, that could only be done from PALcode, and ours doesn't
do that.
But honestly, these are used infrequently enough that they don't
really need to be TCG registers. We wind up with exactly the same
code if we follow the letter of the law and issue explicit ld/st.
Signed-off-by: Richard Henderson <rth@twiddle.net>
This one fixes a bug, previously noted as supressing exceptions
in the (unlikely) case the destination register was $f31.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Peter Maydell