Re: [kvm-unit-tests PATCH v2 02/10] arm64: fix get_"sysreg32" and make MPIDR 64bit

Alex Bennée
2016-06-06T12:47:38Z

Andrew Jones <drjones@redhat.com> writes:

> mrs is always 64bit, so we should always use a 64bit register.
> Sometimes we'll only want to return the lower 32, but not for
> MPIDR, as that does define fields in the upper 32.
>
> Signed-off-by: Andrew Jones <drjones@redhat.com>
> ---
> lib/arm64/asm/processor.h | 15 +++++++++------
> 1 file changed, 9 insertions(+), 6 deletions(-)
>
> diff --git a/lib/arm64/asm/processor.h b/lib/arm64/asm/processor.h
> index 84d5c7ce752b0..9a208ff729b7e 100644
> --- a/lib/arm64/asm/processor.h
> +++ b/lib/arm64/asm/processor.h
> @@ -66,14 +66,17 @@ static inline unsigned long current_level(void)
> return el & 0xc;
> }
>
> -#define DEFINE_GET_SYSREG32(reg) \
> -static inline unsigned int get_##reg(void) \
> +#define DEFINE_GET_SYSREG(reg, type) \
> +static inline type get_##reg(void) \
> { \
> - unsigned int reg; \
> - asm volatile("mrs %0, " #reg "_el1" : "=r" (reg)); \
> - return reg; \
> + unsigned long r; \
> + asm volatile("mrs %0, " #reg "_el1" : "=r" (r)); \
> + return (type)r; \
> }
> -DEFINE_GET_SYSREG32(mpidr)
> +#define DEFINE_GET_SYSREG32(reg) DEFINE_GET_SYSREG(reg, unsigned int)
> +#define DEFINE_GET_SYSREG64(reg) DEFINE_GET_SYSREG(reg, unsigned long)

I guess this is a hang-over the kernel style to use int/long over
u32/u64?

Otherwise:

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>

> +
> +DEFINE_GET_SYSREG64(mpidr)
>
> /* Only support Aff0 for now, gicv2 only */
> #define mpidr_to_cpu(mpidr) ((int)((mpidr) & 0xff))

--
Alex Bennée