On Mon, Apr 18, 2016 at 05:35:30PM +0100, Suzuki K Poulose wrote:
> Add scope parameter to the arm64_cpu_capabilities::matches(), so that
> this can be reused for checking the capability on a given CPU vs the
> system wide. The system uses the default scope associated with the
> capability for initialising the CPU_HWCAPs and ELF_HWCAPs.
>
> Cc: James Morse <[email protected]>
> Cc: Marc Zyngier <[email protected]>
> Cc: Andre Przywara <[email protected]>
> Cc: Will Deacon <[email protected]>
> Cc: Catalin Marinas <[email protected]>
> Signed-off-by: Suzuki K Poulose <[email protected]>
>
> ---
> Changes since V1:
> - Add a default scope for capabilities used by the system checks.
> - Add WARN_ON() for !SCOPE_CPU for midr checks
> ---
> arch/arm64/include/asm/cpufeature.h | 9 ++++++-
> arch/arm64/kernel/cpu_errata.c | 4 ++-
> arch/arm64/kernel/cpufeature.c | 46
> ++++++++++++++++++++++-------------
> 3 files changed, 40 insertions(+), 19 deletions(-)
>
> diff --git a/arch/arm64/include/asm/cpufeature.h
> b/arch/arm64/include/asm/cpufeature.h
> index ca8fb4b..a5a6502 100644
> --- a/arch/arm64/include/asm/cpufeature.h
> +++ b/arch/arm64/include/asm/cpufeature.h
> @@ -78,10 +78,17 @@ struct arm64_ftr_reg {
> struct arm64_ftr_bits *ftr_bits;
> };
>
> +/* scope of capability check */
> +enum {
> + SCOPE_SYSTEM,
> + SCOPE_CPU,
> +};
I think I actually prefer the GLOBAL/LOCAL naming, since SYSTEM is going
to be the scope you want when talking about all CPUs. Or maybe just
rename SCOPE_CPU to SCOPE_LOCAL_CPU.
We might want a preemptible() check when probing SCOPE_CPU properties,
too.
> +
> struct arm64_cpu_capabilities {
> const char *desc;
> u16 capability;
> - bool (*matches)(const struct arm64_cpu_capabilities *);
> + int def_scope; /* default scope */
> + bool (*matches)(const struct arm64_cpu_capabilities *caps, int scope);
> void (*enable)(void *); /* Called on all active CPUs */
> union {
> struct { /* To be used for erratum handling only */
> diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c
> index 06afd04..e171a14 100644
> --- a/arch/arm64/kernel/cpu_errata.c
> +++ b/arch/arm64/kernel/cpu_errata.c
> @@ -22,14 +22,16 @@
> #include <asm/cpufeature.h>
>
> static bool __maybe_unused
> -is_affected_midr_range(const struct arm64_cpu_capabilities *entry)
> +is_affected_midr_range(const struct arm64_cpu_capabilities *entry, int scope)
> {
> + WARN_ON(scope != SCOPE_CPU);
> return MIDR_IS_CPU_MODEL_RANGE(read_cpuid_id(), entry->midr_model,
> entry->midr_range_min,
> entry->midr_range_max);
> }
>
> #define MIDR_RANGE(model, min, max) \
> + .def_scope = SCOPE_CPU, \
> .matches = is_affected_midr_range, \
> .midr_model = model, \
> .midr_range_min = min, \
> diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
> index 8c46621..db392c5 100644
> --- a/arch/arm64/kernel/cpufeature.c
> +++ b/arch/arm64/kernel/cpufeature.c
> @@ -71,7 +71,9 @@ DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
>
> /* meta feature for alternatives */
> static bool __maybe_unused
> -cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry);
> +cpufeature_pan_not_uao(const struct arm64_cpu_capabilities *entry, int
> __unused);
> +
> +static u64 __raw_read_system_reg(u32 sys_id);
Can we not reorder the functions in this file to avoid the internal forward
declarations?
Will
