For cpus using PMSA, when the MPU is disabled, the default memory
type is Normal, Non-cachable. This means that it should not
have alignment restrictions enforced.
Cc: qemu-stable@nongnu.org
Fixes: 59754f85ed ("target/arm: Do memory type alignment check when translation disabled")
Reported-by: Clément Chigot <chigot@adacore.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Clément Chigot <chigot@adacore.com>
Message-id: 20240422170722.117409-1-richard.henderson@linaro.org
[PMM: trivial comment, commit message tweaks]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
If translation is disabled, the default memory type is Device, which
requires alignment checking. This is more optimally done early via
the MemOp given to the TCG memory operation.
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reported-by: Idan Horowitz <idan.horowitz@gmail.com>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20240301204110.656742-6-richard.henderson@linaro.org
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1204
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
FEAT_NV2 requires that when HCR_EL2.{NV,NV2} == 0b11 then accesses by
EL1 to certain system registers are redirected to RAM. The full list
of affected registers is in the table in rule R_CSRPQ in the Arm ARM.
The registers may be normally accessible at EL1 (like ACTLR_EL1), or
normally UNDEF at EL1 (like HCR_EL2). Some registers redirect to RAM
only when HCR_EL2.NV1 is 0, and some only when HCR_EL2.NV1 is 1;
others trap in both cases.
Add the infrastructure for identifying which registers should be
redirected and turning them into memory accesses.
This code does not set the correct syndrome or arrange for the
exception to be taken to the correct target EL if the access via
VNCR_EL2 faults; we will do that in the next commit.
Subsequent commits will mark up the relevant regdefs to set their
nv2_redirect_offset, and if relevant one of the two flags which
indicates that the redirect happens only for a particular value of
HCR_EL2.NV1.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Under FEAT_NV2, when HCR_EL2.{NV,NV2} == 0b11 at EL1, accesses to the
registers SPSR_EL2, ELR_EL2, ESR_EL2, FAR_EL2 and TFSR_EL2 (which
would UNDEF without FEAT_NV or FEAT_NV2) should instead access the
equivalent EL1 registers SPSR_EL1, ELR_EL1, ESR_EL1, FAR_EL1 and
TFSR_EL1.
Because there are only five registers involved and the encoding for
the EL1 register is identical to that of the EL2 register except
that opc1 is 0, we handle this by finding the EL1 register in the
hash table and using it instead.
Note that traps that apply to direct accesses to the EL1 register,
such as active fine-grained traps or other trap bits, do not trigger
when it is accessed via the EL2 encoding in this way. However, some
traps that are defined by the EL2 register may apply. We therefore
call the EL2 register's accessfn first. The only one of the five
which has such traps is TFSR_EL2: make sure its accessfn correctly
handles both FEAT_NV (where we trap to EL2 without checking ATA bits)
and FEAT_NV2 (where we check ATA bits and then redirect to TFSR_EL1).
(We don't need the NV1 tbflag bit until the next patch, but we
introduce it here to avoid putting the NV, NV1, NV2 bits in an
odd order.)
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
FEAT_NV requires (per I_JKLJK) that when HCR_EL2.{NV,NV1} is {1,1} the
unprivileged-access instructions LDTR, STTR etc behave as normal
loads and stores. Implement the check that handles this.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
For FEAT_NV, accesses to system registers and instructions from EL1
which would normally UNDEF there but which work in EL2 need to
instead be trapped to EL2. Detect this both for "we know this will
UNDEF at translate time" and "we found this UNDEFs at runtime", and
make the affected registers trap to EL2 instead.
The Arm ARM defines the set of registers that should trap in terms
of their names; for our implementation this would be both awkward
and inefficent as a test, so we instead trap based on the opc1
field of the sysreg. The regularity of the architectural choice
of encodings for sysregs means that in practice this captures
exactly the correct set of registers.
Regardless of how we try to define the registers this trapping
applies to, there's going to be a certain possibility of breakage
if new architectural features introduce new registers that don't
follow the current rules (FEAT_MEC is one example already visible
in the released sysreg XML, though not yet in the Arm ARM). This
approach seems to me to be straightforward and likely to require
a minimum of manual overrides.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
When FEAT_NV is turned on via the HCR_EL2.NV bit, ERET instructions
are trapped, with the same syndrome information as for the existing
FEAT_FGT fine-grained trap (in the pseudocode this is handled in
AArch64.CheckForEretTrap()).
Rename the DisasContext and tbflag bits to reflect that they are
no longer exclusively for FGT traps, and set the tbflag bit when
FEAT_NV is enabled as well as when the FGT is enabled.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Miguel Luis <miguel.luis@oracle.com>
Fixes: 179e9a3bac "target/arm: Define new TB flag for ATA0"
Fixes: 5d7b37b5f6 "target/arm: Implement the CPY* instructions"
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
The feature test functions isar_feature_*() now take up nearly
a thousand lines in target/arm/cpu.h. This header file is included
by a lot of source files, most of which don't need these functions.
Move the feature test functions to their own header file.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20231024163510.2972081-2-peter.maydell@linaro.org
Currently the only tag-setting instructions always do so in the
context of the current EL, and so we only need one ATA bit in the TB
flags. The FEAT_MOPS SETG instructions include ones which set tags
for a non-privileged access, so we now also need the equivalent "are
tags enabled?" information for EL0.
Add the new TB flag, and convert the existing 'bool ata' field in
DisasContext to a 'bool ata[2]' that can be indexed by the is_unpriv
bit in an instruction, similarly to mte[2].
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230912140434.1333369-9-peter.maydell@linaro.org
The LDRT/STRT "unprivileged load/store" instructions behave like
normal ones if executed at EL0. We handle this correctly for
the load/store semantics, but get the MTE checking wrong.
We always look at s->mte_active[is_unpriv] to see whether we should
be doing MTE checks, but in hflags.c when we set the TB flags that
will be used to fill the mte_active[] array we only set the
MTE0_ACTIVE bit if UNPRIV is true (i.e. we are not at EL0).
This means that a LDRT at EL0 will see s->mte_active[1] as 0,
and will not do MTE checks even when MTE is enabled.
To avoid the translate-time code having to do an explicit check on
s->unpriv to see if it is OK to index into the mte_active[] array,
duplicate MTE_ACTIVE into MTE0_ACTIVE when UNPRIV is false.
(This isn't a very serious bug because generally nobody executes
LDRT/STRT at EL0, because they have no use there.)
Cc: qemu-stable@nongnu.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230912140434.1333369-2-peter.maydell@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20230530191438.411344-16-richard.henderson@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
The hflags are used only for TCG code, so introduce a new file
hflags.c to keep that code.
Signed-off-by: Fabiano Rosas <farosas@suse.de>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>