On Fri, Jan 3, 2025 at 4:28 AM Richard Henderson
<richard.hender...@linaro.org> wrote:
>
> Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
Acked-by: Alistair Francis <alistair.fran...@wdc.com>
Alistair
> ---
> host/include/riscv/host/cpuinfo.h | 5 +++--
> util/cpuinfo-riscv.c | 18 ++++++++++++++++--
> 2 files changed, 19 insertions(+), 4 deletions(-)
>
> diff --git a/host/include/riscv/host/cpuinfo.h
> b/host/include/riscv/host/cpuinfo.h
> index cdc784e7b6..b2b53dbf62 100644
> --- a/host/include/riscv/host/cpuinfo.h
> +++ b/host/include/riscv/host/cpuinfo.h
> @@ -9,8 +9,9 @@
> #define CPUINFO_ALWAYS (1u << 0) /* so cpuinfo is nonzero */
> #define CPUINFO_ZBA (1u << 1)
> #define CPUINFO_ZBB (1u << 2)
> -#define CPUINFO_ZICOND (1u << 3)
> -#define CPUINFO_ZVE64X (1u << 4)
> +#define CPUINFO_ZBS (1u << 3)
> +#define CPUINFO_ZICOND (1u << 4)
> +#define CPUINFO_ZVE64X (1u << 5)
>
> /* Initialized with a constructor. */
> extern unsigned cpuinfo;
> diff --git a/util/cpuinfo-riscv.c b/util/cpuinfo-riscv.c
> index 971c924012..0291b7218a 100644
> --- a/util/cpuinfo-riscv.c
> +++ b/util/cpuinfo-riscv.c
> @@ -36,7 +36,8 @@ static void sigill_handler(int signo, siginfo_t *si, void
> *data)
> /* Called both as constructor and (possibly) via other constructors. */
> unsigned __attribute__((constructor)) cpuinfo_init(void)
> {
> - unsigned left = CPUINFO_ZBA | CPUINFO_ZBB | CPUINFO_ZICOND |
> CPUINFO_ZVE64X;
> + unsigned left = CPUINFO_ZBA | CPUINFO_ZBB | CPUINFO_ZBS
> + | CPUINFO_ZICOND | CPUINFO_ZVE64X;
> unsigned info = cpuinfo;
>
> if (info) {
> @@ -50,6 +51,9 @@ unsigned __attribute__((constructor)) cpuinfo_init(void)
> #if defined(__riscv_arch_test) && defined(__riscv_zbb)
> info |= CPUINFO_ZBB;
> #endif
> +#if defined(__riscv_arch_test) && defined(__riscv_zbs)
> + info |= CPUINFO_ZBS;
> +#endif
> #if defined(__riscv_arch_test) && defined(__riscv_zicond)
> info |= CPUINFO_ZICOND;
> #endif
> @@ -71,7 +75,8 @@ unsigned __attribute__((constructor)) cpuinfo_init(void)
> && pair.key >= 0) {
> info |= pair.value & RISCV_HWPROBE_EXT_ZBA ? CPUINFO_ZBA : 0;
> info |= pair.value & RISCV_HWPROBE_EXT_ZBB ? CPUINFO_ZBB : 0;
> - left &= ~(CPUINFO_ZBA | CPUINFO_ZBB);
> + info |= pair.value & RISCV_HWPROBE_EXT_ZBS ? CPUINFO_ZBS : 0;
> + left &= ~(CPUINFO_ZBA | CPUINFO_ZBB | CPUINFO_ZBS);
> #ifdef RISCV_HWPROBE_EXT_ZICOND
> info |= pair.value & RISCV_HWPROBE_EXT_ZICOND ? CPUINFO_ZICOND :
> 0;
> left &= ~CPUINFO_ZICOND;
> @@ -117,6 +122,15 @@ unsigned __attribute__((constructor)) cpuinfo_init(void)
> left &= ~CPUINFO_ZBB;
> }
>
> + if (left & CPUINFO_ZBS) {
> + /* Probe for Zbs: bext zero,zero,zero. */
> + got_sigill = 0;
> + asm volatile(".insn r 0x33, 5, 0x24, zero, zero, zero"
> + : : : "memory");
> + info |= got_sigill ? 0 : CPUINFO_ZBS;
> + left &= ~CPUINFO_ZBS;
> + }
> +
> if (left & CPUINFO_ZICOND) {
> /* Probe for Zicond: czero.eqz zero,zero,zero. */
> got_sigill = 0;
> --
> 2.43.0
>
>
