Re: [kvm-unit-tests PATCH v2 1/3] arm64: Prepare for LPA2

[Eric Auger <eric.auger@redhat.com>]

Hi Drew,

On 4/2/24 15:27, Andrew Jones wrote:
> When checking for supported granules also check for the values
> which indicate support when LPA2 is implemented.
>
> Signed-off-by: Andrew Jones <andrew.jones@linux.dev>
Reviewed-by: Eric Auger <eric.auger@redhat.com>

Eric
> ---
>  lib/arm64/asm/processor.h | 49 +++++++++++++++++++++------------------
>  1 file changed, 27 insertions(+), 22 deletions(-)
>
> diff --git a/lib/arm64/asm/processor.h b/lib/arm64/asm/processor.h
> index 1c73ba32725a..bab9c26c2c9e 100644
> --- a/lib/arm64/asm/processor.h
> +++ b/lib/arm64/asm/processor.h
> @@ -110,31 +110,36 @@ static inline unsigned long get_id_aa64mmfr0_el1(void)
>  #define ID_AA64MMFR0_TGRAN64_SHIFT	24
>  #define ID_AA64MMFR0_TGRAN16_SHIFT	20
>  
> -#define ID_AA64MMFR0_TGRAN4_SUPPORTED	0x0
> -#define ID_AA64MMFR0_TGRAN64_SUPPORTED	0x0
> -#define ID_AA64MMFR0_TGRAN16_SUPPORTED	0x1
> +#define ID_AA64MMFR0_TGRAN4_SUPPORTED(r)			\
> +({								\
> +	u64 __v = ((r) >> ID_AA64MMFR0_TGRAN4_SHIFT) & 0xf;	\
> +	(__v) == 0 || (__v) == 1;				\
> +})
> +
> +#define ID_AA64MMFR0_TGRAN64_SUPPORTED(r)			\
> +({								\
> +	u64 __v = ((r) >> ID_AA64MMFR0_TGRAN64_SHIFT) & 0xf;	\
> +	(__v) == 0;						\
> +})
> +
> +#define ID_AA64MMFR0_TGRAN16_SUPPORTED(r)			\
> +({								\
> +	u64 __v = ((r) >> ID_AA64MMFR0_TGRAN16_SHIFT) & 0xf;	\
> +	(__v) == 1 || (__v) == 2;				\
> +})
>  
>  static inline bool system_supports_granule(size_t granule)
>  {
> -	u32 shift;
> -	u32 val;
> -	u64 mmfr0;
> -
> -	if (granule == SZ_4K) {
> -		shift = ID_AA64MMFR0_TGRAN4_SHIFT;
> -		val = ID_AA64MMFR0_TGRAN4_SUPPORTED;
> -	} else if (granule == SZ_16K) {
> -		shift = ID_AA64MMFR0_TGRAN16_SHIFT;
> -		val = ID_AA64MMFR0_TGRAN16_SUPPORTED;
> -	} else {
> -		assert(granule == SZ_64K);
> -		shift = ID_AA64MMFR0_TGRAN64_SHIFT;
> -		val = ID_AA64MMFR0_TGRAN64_SUPPORTED;
> -	}
> -
> -	mmfr0 = get_id_aa64mmfr0_el1();
> -
> -	return ((mmfr0 >> shift) & 0xf) == val;
> +	u64 mmfr0 = get_id_aa64mmfr0_el1();
> +
> +	if (granule == SZ_4K)
> +		return ID_AA64MMFR0_TGRAN4_SUPPORTED(mmfr0);
> +
> +	if (granule == SZ_16K)
> +		return ID_AA64MMFR0_TGRAN16_SUPPORTED(mmfr0);
> +
> +	assert(granule == SZ_64K);
> +	return ID_AA64MMFR0_TGRAN64_SUPPORTED(mmfr0);
>  }
>  
>  #endif /* !__ASSEMBLY__ */