[RFC PATCH 1/3] arm64: Append more field of id_aa64mmfr2 for cpufeature

[Mark Rutland]

On Fri, Mar 25, 2016 at 05:30:07PM +0800, Kefeng Wang wrote:
> There are some new cpu features which can be identified by id_aa64mmfr2,
> this patch appends all fields of it.

FWIW, this looks like a good thing regardless of the cpuinfo patches.

The shifts look right to me. I'm not all that familiar with each of the
features, so I don't know whether or not we need strict exact matching
(though it's a safer to assume that we do for now).

Mark.

> 
> Signed-off-by: Kefeng Wang <wangkefeng.wang at huawei.com>
> ---
>  arch/arm64/include/asm/sysreg.h | 4 ++++
>  arch/arm64/kernel/cpufeature.c  | 4 ++++
>  2 files changed, 8 insertions(+)
> 
> diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
> index 1a78d6e..c141243 100644
> --- a/arch/arm64/include/asm/sysreg.h
> +++ b/arch/arm64/include/asm/sysreg.h
> @@ -142,7 +142,11 @@
>  #define ID_AA64MMFR1_HADBS_SHIFT	0
>  
>  /* id_aa64mmfr2 */
> +#define ID_AA64MMFR2_LVA_SHIFT		16
> +#define ID_AA64MMFR2_IESB_SHIFT		12
> +#define ID_AA64MMFR2_LSM_SHIFT		8
>  #define ID_AA64MMFR2_UAO_SHIFT		4
> +#define ID_AA64MMFR2_CNP_SHIFT		0
>  
>  /* id_aa64dfr0 */
>  #define ID_AA64DFR0_CTX_CMPS_SHIFT	28
> diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
> index 943f514..677f17c 100644
> --- a/arch/arm64/kernel/cpufeature.c
> +++ b/arch/arm64/kernel/cpufeature.c
> @@ -130,7 +130,11 @@ static struct arm64_ftr_bits ftr_id_aa64mmfr1[] = {
>  };
>  
>  static struct arm64_ftr_bits ftr_id_aa64mmfr2[] = {
> +	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LVA_SHIFT, 4, 0),
> +	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_IESB_SHIFT, 4, 0),
> +	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_LSM_SHIFT, 4, 0),
>  	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_UAO_SHIFT, 4, 0),
> +	ARM64_FTR_BITS(FTR_STRICT, FTR_EXACT, ID_AA64MMFR2_CNP_SHIFT, 4, 0),
>  	ARM64_FTR_END,
>  };
>  
> -- 
> 1.7.12.4
>