Re: [kvm-unit-tests RFC 01/10] arm64: Provide read/write_sysreg_s

[Alexandru Elisei <alexandru.elisei@arm.com>]

Hi,

On 12/6/19 5:27 PM, Eric Auger wrote:
> From: Andrew Jones <drjones@redhat.com>
>
> Sometimes we need to test access to system registers which are
> missing assembler mnemonics.
>
> Signed-off-by: Andrew Jones <drjones@redhat.com>
> ---
>  lib/arm64/asm/sysreg.h | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/lib/arm64/asm/sysreg.h b/lib/arm64/asm/sysreg.h
> index a03830b..a45eebd 100644
> --- a/lib/arm64/asm/sysreg.h
> +++ b/lib/arm64/asm/sysreg.h
> @@ -38,6 +38,17 @@
>  	asm volatile("msr " xstr(r) ", %x0" : : "rZ" (__val));	\
>  } while (0)
>  
> +#define read_sysreg_s(r) ({					\
> +	u64 __val;						\
> +	asm volatile("mrs_s %0, " xstr(r) : "=r" (__val));	\
> +	__val;							\
> +})
> +
> +#define write_sysreg_s(v, r) do {				\
> +	u64 __val = (u64)v;					\
> +	asm volatile("msr_s " xstr(r) ", %x0" : : "rZ" (__val));\
> +} while (0)
> +
>  asm(
>  "	.irp	num,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30\n"
>  "	.equ	.L__reg_num_x\\num, \\num\n"

That's exactly the code that I wrote for my EL2 series :)

Reviewed-by: Alexandru Elisei <alexandru.elisei@arm.com>

Thanks,
Alex