From: James Morse james.morse@arm.com
commit 1c0763037f1e1caef739e36e09c6d41ed7b61b2d upstream.
This patch adds an 'enable()' callback to cpu capability/feature detection, allowing features that require some setup or configuration to get this opportunity once the feature has been detected.
Acked-by: Catalin Marinas catalin.marinas@arm.com Signed-off-by: James Morse james.morse@arm.com Signed-off-by: Will Deacon will.deacon@arm.com Signed-off-by: David Brown david.brown@linaro.org --- arch/arm64/include/asm/cpufeature.h | 1 + arch/arm64/kernel/cpufeature.c | 6 ++++++ 2 files changed, 7 insertions(+)
diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 9fafa75..484fa94 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -34,6 +34,7 @@ struct arm64_cpu_capabilities { const char *desc; u16 capability; bool (*matches)(const struct arm64_cpu_capabilities *); + void (*enable)(void); union { struct { /* To be used for erratum handling only */ u32 midr_model; diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 5ad86ce..650ffc2 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -55,6 +55,12 @@ void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps, pr_info("%s %s\n", info, caps[i].desc); cpus_set_cap(caps[i].capability); } + + /* second pass allows enable() to consider interacting capabilities */ + for (i = 0; caps[i].desc; i++) { + if (cpus_have_cap(caps[i].capability) && caps[i].enable) + caps[i].enable(); + } }
void check_local_cpu_features(void)