On 4/1/20 6:33 PM, David Hildenbrand wrote:
> STFLE operates on doublewords, not bytes. Passing in "256" resulted in
> some ignored bits getting set. Not bad, but also not clean.
>
> Let's just convert our stfle handling code to operate on doublewords.
>
> Signed-off-by: David Hildenbrand <david@xxxxxxxxxx>
Reviewed-by: Janosch Frank <frankja@xxxxxxxxxxxxx>
> ---
> lib/s390x/asm/facility.h | 14 +++++++-------
> lib/s390x/io.c | 2 +-
> 2 files changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/lib/s390x/asm/facility.h b/lib/s390x/asm/facility.h
> index e34dc2c..def2705 100644
> --- a/lib/s390x/asm/facility.h
> +++ b/lib/s390x/asm/facility.h
> @@ -14,12 +14,12 @@
> #include <asm/facility.h>
> #include <asm/arch_def.h>
>
> -#define NR_STFL_BYTES 256
> -extern uint8_t stfl_bytes[];
> +#define NB_STFL_DOUBLEWORDS 32
> +extern uint64_t stfl_doublewords[];
>
> static inline bool test_facility(int nr)
> {
> - return stfl_bytes[nr / 8] & (0x80U >> (nr % 8));
> + return stfl_doublewords[nr / 64] & (0x8000000000000000UL >> (nr % 64));
> }
>
> static inline void stfl(void)
> @@ -27,9 +27,9 @@ static inline void stfl(void)
> asm volatile(" stfl 0(0)\n" : : : "memory");
> }
>
> -static inline void stfle(uint8_t *fac, unsigned int len)
> +static inline void stfle(uint64_t *fac, unsigned int nb_doublewords)
> {
> - register unsigned long r0 asm("0") = len - 1;
> + register unsigned long r0 asm("0") = nb_doublewords - 1;
>
> asm volatile(" .insn s,0xb2b00000,0(%1)\n"
> : "+d" (r0) : "a" (fac) : "memory", "cc");
> @@ -40,9 +40,9 @@ static inline void setup_facilities(void)
> struct lowcore *lc = NULL;
>
> stfl();
> - memcpy(stfl_bytes, &lc->stfl, sizeof(lc->stfl));
> + memcpy(stfl_doublewords, &lc->stfl, sizeof(lc->stfl));
> if (test_facility(7))
> - stfle(stfl_bytes, NR_STFL_BYTES);
> + stfle(stfl_doublewords, NB_STFL_DOUBLEWORDS);
> }
>
> #endif
> diff --git a/lib/s390x/io.c b/lib/s390x/io.c
> index e091c37..c0f0bf7 100644
> --- a/lib/s390x/io.c
> +++ b/lib/s390x/io.c
> @@ -19,7 +19,7 @@
> #include "smp.h"
>
> extern char ipl_args[];
> -uint8_t stfl_bytes[NR_STFL_BYTES] __attribute__((aligned(8)));
> +uint64_t stfl_doublewords[NB_STFL_DOUBLEWORDS];
>
> static struct spinlock lock;
>
>
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