Commit Graph

7 Commits

Author SHA1 Message Date
Peter Maydell 2f2a00aec9 target-arm: Move arm_log_exception() into internals.h
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>
2014-04-17 21:34:04 +01:00
Peter Maydell f502cfc207 target-arm: Implement SP_EL0, SP_EL1
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>
2014-04-17 21:34:04 +01:00
Peter Maydell 8c6afa6ab1 target-arm: A64: Correctly fault FP/Neon if CPACR.FPEN set
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.
2014-04-17 21:34:03 +01:00
Rob Herring 00892383c9 target-arm: Provide syndrome information for MMU faults
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>
2014-04-17 21:34:03 +01:00
Peter Maydell d4a2dc675b target-arm: Add support for generating exceptions with syndrome information
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>
2014-04-17 21:34:03 +01:00
Peter Maydell 8bcbf37caa target-arm: Provide correct syndrome information for cpreg access traps
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>
2014-04-17 21:34:03 +01:00
Peter Maydell ccd380876b target-arm: Split out private-to-target functions into internals.h
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>
2014-04-17 21:34:03 +01:00