diff options
| author | Kristina Martsenko <kristina.martsenko@arm.com> | 2023-05-09 15:22:34 +0100 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2023-06-05 17:05:42 +0100 |
| commit | 3e1dedb29d0f70b0bd10bb83001df8c04fc246eb (patch) | |
| tree | f0d8f0cf4586167917a9cf414a1f63f858d3e00c | |
| parent | b7564127ffcb1a26854d7515a0918d775e663639 (diff) | |
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>
| -rw-r--r-- | Documentation/admin-guide/kernel-parameters.txt | 3 | ||||
| -rw-r--r-- | arch/arm64/kernel/idreg-override.c | 2 |
2 files changed, 5 insertions, 0 deletions
diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 9e5bab29685f..e01fbfd78ae9 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -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 diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 370ab84fd06e..8439248c21d3 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -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" }, }; |