diff options
| author | Suzuki K Poulose <suzuki.poulose@arm.com> | 2018-03-26 17:12:39 +0300 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2018-03-26 20:01:40 +0300 |
| commit | 5c137714dd8cae464dbd5f028c07af149e6d09fc (patch) | |
| tree | 7d6282860baf80e1571cd7886e0f8625470332a0 /arch/arm64/include/asm/cpufeature.h | |
| parent | ed478b3f9e4ac97fdbe07007fb2662415de8fe25 (diff) | |
| download | linux-5c137714dd8cae464dbd5f028c07af149e6d09fc.tar.xz | |
arm64: capabilities: Introduce weak features based on local CPU
Now that we have the flexibility of defining system features based
on individual CPUs, introduce CPU feature type that can be detected
on a local SCOPE and ignores the conflict on late CPUs. This is
applicable for ARM64_HAS_NO_HW_PREFETCH, where it is fine for
the system to have CPUs without hardware prefetch turning up
later. We only suffer a performance penalty, nothing fatal.
Cc: Will Deacon <will.deacon@arm.com>
Reviewed-by: Dave Martin <dave.martin@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'arch/arm64/include/asm/cpufeature.h')
| -rw-r--r-- | arch/arm64/include/asm/cpufeature.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index c187b926daf9..effb1c038221 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -239,6 +239,14 @@ extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0; */ #define ARM64_CPUCAP_SYSTEM_FEATURE \ (ARM64_CPUCAP_SCOPE_SYSTEM | ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU) +/* + * CPU feature detected at boot time based on feature of one or more CPUs. + * All possible conflicts for a late CPU are ignored. + */ +#define ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE \ + (ARM64_CPUCAP_SCOPE_LOCAL_CPU | \ + ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU | \ + ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU) struct arm64_cpu_capabilities { const char *desc; |