arm64: mops: allow disabling MOPS from the kernel command line

Make it possible to disable the MOPS extension at runtime using the
kernel command line. This can be useful for testing or working around
hardware issues. For example it could be used to test new memory copy
routines that do not use MOPS instructions (e.g. from Arm Optimized
Routines).

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
Link: https://lore.kernel.org/r/20230509142235.3284028-11-kristina.martsenko@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
This commit is contained in:
Kristina Martsenko 2023-05-09 15:22:34 +01:00 committed by Catalin Marinas
parent b7564127ff
commit 3e1dedb29d
2 changed files with 5 additions and 0 deletions

View file

@ -429,6 +429,9 @@
arm64.nosme [ARM64] Unconditionally disable Scalable Matrix
Extension support
arm64.nomops [ARM64] Unconditionally disable Memory Copy and Memory
Set instructions support
ataflop= [HW,M68k]
atarimouse= [HW,MOUSE] Atari Mouse

View file

@ -123,6 +123,7 @@ static const struct ftr_set_desc isar2 __initconst = {
.fields = {
FIELD("gpa3", ID_AA64ISAR2_EL1_GPA3_SHIFT, NULL),
FIELD("apa3", ID_AA64ISAR2_EL1_APA3_SHIFT, NULL),
FIELD("mops", ID_AA64ISAR2_EL1_MOPS_SHIFT, NULL),
{}
},
};
@ -174,6 +175,7 @@ static const struct {
"id_aa64isar1.gpi=0 id_aa64isar1.gpa=0 "
"id_aa64isar1.api=0 id_aa64isar1.apa=0 "
"id_aa64isar2.gpa3=0 id_aa64isar2.apa3=0" },
{ "arm64.nomops", "id_aa64isar2.mops=0" },
{ "arm64.nomte", "id_aa64pfr1.mte=0" },
{ "nokaslr", "kaslr.disabled=1" },
};