arm64: Add framework for legacy instruction emulation

Browse source

Typically, providing support for legacy instructions requires
emulating the behaviour of instructions whose encodings have become
undefined. If the instructions haven't been removed from the
architecture, there maybe an option in the implementation to turn
on/off the support for these instructions.

Create common infrastructure to support legacy instruction
emulation. In addition to emulation, also provide an option to support
hardware execution when supported. The default execution mode (one of
undef, emulate, hw exeuction) is dependent on the state of the
instruction (deprecated or obsolete) in the architecture and
can specified at the time of registering the instruction handlers. The
runtime state of the emulation can be controlled by writing to
individual nodes in sysctl. The expected default behaviour is
documented as part of this patch.

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Punit Agrawal <punit.agrawal@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

...

This commit is contained in:

Punit Agrawal 2014-11-18 11:41:24 +00:00 • committed by Will Deacon

parent 0be0e44c18

commit 587064b610

4 changed files with 268 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

33

Documentation/arm64/legacy_instructions.txt

View file

18

arch/arm64/Kconfig

View file

1

arch/arm64/kernel/Makefile

View file

216

arch/arm64/kernel/armv8_deprecated.c

View file