Re: [kvm-unit-tests PATCH v6 02/10] s390x: Use PSW bits definitions in cstart

David Hildenbrand
2020-04-27T09:01:57Z

On 24.04.20 12:45, Pierre Morel wrote:
> This patch defines the PSW bits EA/BA used to initialize the PSW masks
> for exceptions.
>
> Since some PSW mask definitions exist already in arch_def.h we add these
> definitions there.
> We move all PSW definitions together and protect assembler code against
> C syntax.
>
> Signed-off-by: Pierre Morel <pmorel@linux.ibm.com>
> ---
> lib/s390x/asm/arch_def.h | 16 ++++++++++++----
> s390x/cstart64.S | 15 ++++++++-------
> 2 files changed, 20 insertions(+), 11 deletions(-)
>
> diff --git a/lib/s390x/asm/arch_def.h b/lib/s390x/asm/arch_def.h
> index 15a4d49..c54409a 100644
> --- a/lib/s390x/asm/arch_def.h
> +++ b/lib/s390x/asm/arch_def.h
> @@ -10,15 +10,22 @@
> #ifndef _ASM_S390X_ARCH_DEF_H_
> #define _ASM_S390X_ARCH_DEF_H_
>
> +#define PSW_MASK_EXT 0x0100000000000000UL
> +#define PSW_MASK_DAT 0x0400000000000000UL
> +#define PSW_MASK_SHORT_PSW 0x0008000000000000UL
> +#define PSW_MASK_PSTATE 0x0001000000000000UL
> +#define PSW_MASK_BA 0x0000000080000000UL
> +#define PSW_MASK_EA 0x0000000100000000UL
> +
> +#define PSW_EXCEPTION_MASK (PSW_MASK_EA | PSW_MASK_BA)
> +#define PSW_RESET_MASK (PSW_EXCEPTION_MASK | PSW_MASK_SHORT_PSW)
> +
> +#ifndef __ASSEMBLER__
> struct psw {
> uint64_t mask;
> uint64_t addr;
> };
>
> -#define PSW_MASK_EXT 0x0100000000000000UL
> -#define PSW_MASK_DAT 0x0400000000000000UL
> -#define PSW_MASK_PSTATE 0x0001000000000000UL
> -
> #define CR0_EXTM_SCLP 0X0000000000000200UL
> #define CR0_EXTM_EXTC 0X0000000000002000UL
> #define CR0_EXTM_EMGC 0X0000000000004000UL
> @@ -297,4 +304,5 @@ static inline uint32_t get_prefix(void)
> return current_prefix;
> }
>
> +#endif /* __ASSEMBLER */
> #endif
> diff --git a/s390x/cstart64.S b/s390x/cstart64.S
> index ba2e67c..e394b3a 100644
> --- a/s390x/cstart64.S
> +++ b/s390x/cstart64.S
> @@ -12,6 +12,7 @@
> */
> #include <asm/asm-offsets.h>
> #include <asm/sigp.h>
> +#include <asm/arch_def.h>
>
> .section .init
>
> @@ -225,19 +226,19 @@ svc_int:
>
> .align 8
> reset_psw:
> - .quad 0x0008000180000000
> + .quad PSW_RESET_MASK

I'd really prefer

.quad PSW_EXCEPTION_MASK | PSW_MASK_SHORT_PSW

here instead and drop PSW_RESET_MASK. Makes it clearer that we are
talking about a special short psw here.

Apart from that, looks good to me.

--
Thanks,

David / dhildenb