This adds the Linux-specific function call to detect CPU features. Unlike the more portable auxillary vector, this supports extensions other than single lettered ones. At this point, FFmpeg already needs this to detect Zba and Zbb at run-time, and probably will need it for Zvbb in the near future.
Support will be available in glibc 2.40 onward. --- configure | 3 +++ libavutil/riscv/cpu.c | 25 +++++++++++++++++++++++++ 2 files changed, 28 insertions(+) diff --git a/configure b/configure index ed74583a6f..bc8f40ed85 100755 --- a/configure +++ b/configure @@ -2298,6 +2298,7 @@ HEADERS_LIST=" OpenGL_gl3_h poll_h pthread_np_h + sys_hwprobe_h sys_param_h sys_resource_h sys_select_h @@ -5537,6 +5538,8 @@ elif enabled ppc; then elif enabled riscv; then + check_headers sys/hwprobe.h + if test_cpp_condition stddef.h "__riscv_zbb"; then enable fast_clz fi diff --git a/libavutil/riscv/cpu.c b/libavutil/riscv/cpu.c index 984293aef0..c3683b06d0 100644 --- a/libavutil/riscv/cpu.c +++ b/libavutil/riscv/cpu.c @@ -18,8 +18,10 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +#define _GNU_SOURCE #include "libavutil/cpu.h" #include "libavutil/cpu_internal.h" +#include "libavutil/macros.h" #include "libavutil/log.h" #include "config.h" @@ -27,10 +29,33 @@ #include <sys/auxv.h> #define HWCAP_RV(letter) (1ul << ((letter) - 'A')) #endif +#ifdef HAVE_SYS_HWPROBE_H +#include <sys/hwprobe.h> +#endif int ff_get_cpu_flags_riscv(void) { int ret = 0; +#ifdef HAVE_SYS_HWPROBE_H + struct riscv_hwprobe pairs[] = { + { RISCV_HWPROBE_KEY_BASE_BEHAVIOR, 0 }, + { RISCV_HWPROBE_KEY_IMA_EXT_0, 0 }, + }; + + if (__riscv_hwprobe(pairs, FF_ARRAY_ELEMS(pairs), 0, NULL, 0) == 0) { + if (pairs[0].value & RISCV_HWPROBE_BASE_BEHAVIOR_IMA) + ret |= AV_CPU_FLAG_RVI; + if (pairs[1].value & RISCV_HWPROBE_IMA_FD) + ret |= AV_CPU_FLAG_RVF | AV_CPU_FLAG_RVD; + if (pairs[1].value & RISCV_HWPROBE_IMA_V) + ret |= AV_CPU_FLAG_RVV_I32 | AV_CPU_FLAG_RVV_I64 + | AV_CPU_FLAG_RVV_F32 | AV_CPU_FLAG_RVV_F64; + if (pairs[1].value & RISCV_HWPROBE_EXT_ZBA) + ret |= AV_CPU_FLAG_RVB_ADDR; + if (pairs[1].value & RISCV_HWPROBE_EXT_ZBB) + ret |= AV_CPU_FLAG_RVB_BASIC; + } else +#endif #if HAVE_GETAUXVAL { const unsigned long hwcap = getauxval(AT_HWCAP); -- 2.43.0 _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org https://ffmpeg.org/mailman/listinfo/ffmpeg-devel To unsubscribe, visit link above, or email ffmpeg-devel-requ...@ffmpeg.org with subject "unsubscribe".