Implement SCTLR.EE bit which controls data endianess for exceptions
and page table translations. SCTLR.EE is mirrored to the CPSR.E bit
on exception entry.
Backports commit 73462dddf670c32c45c8ea359658092b0365b2d4 from qemu
endian with address manipulations on subword accesses (to give the
illusion of BE). But user-mode cannot tell the difference and is
already implemented as straight BE. So handle the difference in the
endianess query, where USER mode is BE and system is not.
Backports commit b2e62d9a7b9a2eb10e451a57813bad168376e122 from qemu
There is a CPU data endianness test that is used to drive the
virtio_big_endian test.
Move this up to the header so it can be more generally used for endian
tests. The KVM specific cpu_syncronize_state call is left behind in the
virtio specific function.
Rename it arm_cpu-data_is_big_endian() to more accurately capture that
this is for data accesses only.
Backports commit ed50ff7875d61a75517c92deb0444d73fbbca878 from qemu
bswap_code is a CPU property of sorts ("is the iside endianness the
opposite way round to TARGET_WORDS_BIGENDIAN?") but it is not the
actual CPU state involved here which is SCTLR.B (set for BE32
binaries, clear for BE8).
Replace bswap_code with SCTLR.B, and pass that to arm_ld*_code.
The next patches will make data fetches honor both SCTLR.B and
CPSR.E appropriately.
Backports commit f9fd40ebe4f55e0048e002925b8d65e66d56e7a7 from qemu
In helper.c the expression
(env->uncached_cpsr & CPSR_M) != CPSR_USER
is always true; the right hand side was supposed to be ARM_CPU_MODE_USR
(an error in commit cb01d391).
Since the incorrect expression was always true, this just meant that
commit cb01d391 had no effect.
However simply changing the RHS here would reveal a logic error: if
the mode is USR we wish to completely ignore the attempt to set the
mode bits, which means that we must clear the CPSR_M bits from mask
to avoid the uncached_cpsr bits being updated at the end of the
function.
Move the condition into the correct place in the code, fix its RHS
constant, and add a comment about the fact that we must be doing a
gdbstub write if we're in user mode.
Backports commit 8c4f0eb94cc65ee32a12feba88d0b32e3665d5ea from qemu
The target-dependant type TCGv must be defined in "tcg/tcg.h" before
including the tracing helper wrappers in "tcg/tcg-op.h".
It also makes more sense to define it here, where other TCG types are
defined too.
Backports commit 5d4e1a1081d3f1ec2908ff0eaebe312389971ab4 from qemu
Adds the 'TCGv_env' type for pointers to 'CPUArchState' objects. The
tracing infrastructure later needs to differentiate between regular
pointers and pointers to vCPUs.
Also changes all targets to use the new 'TCGv_env' type instead of the
generic 'TCGv_ptr'. As of now, the change is merely cosmetic ('TCGv_env'
translates into 'TCGv_ptr'), but that could change in the future to
enforce the difference.
Note that a 'TCGv_env' type (for 'CPUState') is not added, since all
helpers currently receive the architecture-specific
pointer ('CPUArchState').
Backports commit 1bcea73e13b2b059d0cb3301aeaca43e5656ef57 from qemu
The v8 ARM ARM defines that unused spaces in the ID_AA64* system
register ranges are Reserved and must RAZ, rather than being UNDEF.
Implement this.
In particular, ARM v8.2 adds a new feature register ID_AA64MMFR2,
and newer versions of the Linux kernel will attempt to read this,
which causes them not to boot up on versions of QEMU missing this fix.
Since the encoding .opc0 = 3, .opc1 = 0, .crn = 0, .crm = 2, .opc2 = 6
is actually defined in ARMv8 (as ID_MMFR4), we give it an entry in
the ARMCPU struct so CPUs can override it, though since none do
this too will just RAZ.
Backports commit e20d84c1407d43d5a2e2ac95dbb46db3b0af8f9f from qemu
Mark CNTHP_TVAL_EL2 as ARM_CP_NO_RAW due to the register not
having any underlying state. This fixes an issue with booting
KVM enabled kernels when EL2 is on.
Backports commit d44ec156300a149b386a14d3ab349d3b83b66b8c from qemu
Implement the performance monitor register traps controlled
by MDCR_EL3.TPM and MDCR_EL2.TPM. Most of the performance
registers already have an access function to deal with the
user-enable bit, and the TPM checks can be added there. We
also need a new access function which only implements the
TPM checks for use by the few not-EL0-accessible registers
and by PMUSERENR_EL0 (which is always EL0-readable).
Backports commit 1fce1ba985d9c5c96e5b9709e1356d1814b8fa9e from qemu
Fix two issues with our implementation of the SDCR:
* it is only present from ARMv8 onwards
* it does not contain several of the trap bits present in its 64-bit
counterpart the MDCR_EL3
Put the register description in the right place so that it does not
get enabled for ARMv7 and earlier, and give it a write function so that
we can mask out the bits which should not be allowed to have an effect
if EL3 is 32-bit.
Backports commit a8d64e735182cbbb5dcc98f41656b118c45e57cc from qemu
If HCR.TGE is 1 then mode changes via CPS and MSR from Monitor to
NonSecure PL1 modes are illegal mode changes. Implement this check
in bad_mode_switch().
(We don't currently implement HCR.TGE, but this is the only missing
check from the v8 ARM ARM G1.9.3 and so it's worth adding now; the
rest of the HCR.TGE checks can be added later as necessary.)
Backports commit 10eacda787ac9990dc22d4437b289200c819712c from qemu
Mode switches from Hyp to any other mode via the CPS and MRS
instructions are illegal mode switches (though obviously switching
via exception return is valid). Add this check to bad_mode_switch().
Backports commit af393ffc6da116b9dd4c70901bad1f4cafb1773d from qemu
In v8, the illegal mode changes which are UNPREDICTABLE in v7 are
given architected behaviour:
* the mode field is unchanged
* PSTATE.IL is set (so any subsequent instructions will UNDEF)
* any other CPSR fields are written to as normal
This is pretty much the same behaviour we picked for our
UNPREDICTABLE handling, with the exception that for v8 we
need to set the IL bit.
Backports commit 81907a582901671c15be36a63b5063f88f3487e2 from qemu
In v8 trying to switch mode to Mon from Secure EL1 is an
illegal mode switch. (In v7 this is impossible as all secure
modes except User are at EL3.) We can handle this case by
making a switch to Mon valid only if the current EL is 3,
which then gives the correct answer whether EL3 is AArch32
or AArch64.
Backports commit 58ae2d1f037fae1d90eed4522053a85d79edfbec from qemu
We don't actually support Hyp mode yet, but add the correct
checks for it to the bad_mode_switch() function for completeness.
Backports commit e6c8fc07b4fce0729bb747770756835f4b0ca7f4 from qemu
QEMU doesn't implement the NSACR.RFR bit, which is a permitted
IMPDEF in choice in ARMv7 and the only permitted choice in ARMv8.
Add a comment to bad_mode_switch() to note that this is why
FIQ is always a valid mode regardless of the CPU's Secure state.
Backports commit 52ff951b4f63a29593650a15efdf82f63d6d962d from qemu
The only case where we can attempt a cpsr_write() mode switch from
User is from the gdbstub; all other cases are handled in the
calling code (notably translate.c). Architecturally attempts to
alter the mode bits from user mode are simply ignored (and not
treated as a bad mode switch, which in v8 sets CPSR.IL). Make
mode switches from User ignored in cpsr_write() as well, for
consistency.
Backports commit cb01d3912c8b000ed26d5fe95f6c194b3e3ba7a6 from qemu
Raw CPSR writes should skip the architectural checks for whether
we're allowed to set the A or F bits and should also not do
the switching of register banks if the mode changes. Handle
this inside cpsr_write(), which allows us to drop the "manually
set the mode bits to avoid the bank switch" code from all the
callsites which are using CPSRWriteRaw.
This fixes a bug in 32-bit KVM handling where we had forgotten
the "manually set the mode bits" part and could thus potentially
trash the register state if the mode from the last exit to userspace
differed from the mode on this exit.
Backports commit f8c88bbcda76d5674e4bb125471371b41d330df8 from qemu
