Starting with the ARMv7 Virtualization Extensions, the A32 and T32
instruction sets provide instructions "MSR (banked)" and "MRS
(banked)" which can be used to access registers for a mode other
than the current one:
* R<m>_<mode>
* ELR_hyp
* SPSR_<mode>
Implement the missing instructions.
Backports commit 8bfd0550be821cf27d71444e2af350de3c3d2ee3 from qemu
Since this is not a high-performance path, just use a helper to
flip the E bit and force a lookup in the hash table since the
flags have changed.
Backports commit 9886ecdf31165de2d4b8bccc1a220bd6ac8bc192 from qemu
The rules for setting the CPSR on a 32-bit exception return are
subtly different from those for setting the CPSR via an instruction
like MSR or CPS. (In particular, in Hyp mode changing the mode bits
is not valid via MSR or CPS.) Split the exception-return case into
its own helper for setting CPSR, so we can eventually handle them
differently in the helper function.
Backports commit 235ea1f5c89abf30e452539b973b0dbe43d3fe2b from qemu
System registers might have access requirements which need to
be described via a CPAccessFn and which differ for reads and
writes. For this to be possible we need to pass the access
function a parameter to tell it whether the access being checked
is a read or a write.
Backports commit 3f208fd76bcc91a8506681bb8472f2398fe6f487 from qemu
A QEMU breakpoint match is not definitely an architectural breakpoint
match. If an exception is generated unconditionally during translation,
it is hardly possible to ignore it in the debug exception handler.
Generate a call to a helper to check CPU breakpoints and raise an
exception only if any breakpoint matches architecturally.
Backports commit 5d98bf8f38c17a348ab6e8af196088cd4953acd0 from qemu
Currently we use DISAS_WFE for both WFE and YIELD instructions.
This is functionally correct because at the moment both of them
are implemented as "yield this CPU back to the top level loop so
another CPU has a chance to run". However it's rather confusing
that YIELD ends up calling HELPER(wfe), and if we ever want to
implement real behaviour for WFE and SEV it's likely to trip us up.
Split out the yield codepath to use DISAS_YIELD and a new
HELPER(yield) function, and have HELPER(wfe) call HELPER(yield).
Backports commit 049e24a191c212d9468db84169197887f2c91586 from qemu
Add a CPU state exception target EL field that will be used for communicating
the EL to which an exception should be routed.
Add a disassembly context field for tracking the EL3 architecture needed for
determining the target exception EL.
Add a target EL argument to the generic exception helper for callers to specify
the EL to which the exception should be routed. Extended the helper to set
the newly added CPU state exception target el.
Added a function for setting the target exception EL and updated calls to helpers
to call it.
Backports commit 737103619869600668cc7e8700e4f6eab3943896 from qemu
