/* * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "libavutil/cpu.h" #include "libavutil/cpu_internal.h" #include "config.h" #define CORE_FLAG(f) \ (AV_CPU_FLAG_ ## f * (HAVE_ ## f ## _EXTERNAL || HAVE_ ## f ## _INLINE)) #define CORE_CPU_FLAGS \ (CORE_FLAG(ARMV5TE) | \ CORE_FLAG(ARMV6) | \ CORE_FLAG(ARMV6T2) | \ CORE_FLAG(VFP) | \ CORE_FLAG(VFPV3) | \ CORE_FLAG(NEON)) #if defined __linux__ || defined __ANDROID__ #include <stdint.h> #include <stdio.h> #include <string.h> #include "libavutil/avstring.h" #define AT_HWCAP 16 /* Relevant HWCAP values from kernel headers */ #define HWCAP_VFP (1 << 6) #define HWCAP_EDSP (1 << 7) #define HWCAP_THUMBEE (1 << 11) #define HWCAP_NEON (1 << 12) #define HWCAP_VFPv3 (1 << 13) #define HWCAP_TLS (1 << 15) static int get_hwcap(uint32_t *hwcap) { struct { uint32_t a_type; uint32_t a_val; } auxv; FILE *f = fopen("/proc/self/auxv", "r"); int err = -1; if (!f) return -1; while (fread(&auxv, sizeof(auxv), 1, f) > 0) { if (auxv.a_type == AT_HWCAP) { *hwcap = auxv.a_val; err = 0; break; } } fclose(f); return err; } static int get_cpuinfo(uint32_t *hwcap) { FILE *f = fopen("/proc/cpuinfo", "r"); char buf[200]; if (!f) return -1; *hwcap = 0; while (fgets(buf, sizeof(buf), f)) { if (av_strstart(buf, "Features", NULL)) { if (strstr(buf, " edsp ")) *hwcap |= HWCAP_EDSP; if (strstr(buf, " tls ")) *hwcap |= HWCAP_TLS; if (strstr(buf, " thumbee ")) *hwcap |= HWCAP_THUMBEE; if (strstr(buf, " vfp ")) *hwcap |= HWCAP_VFP; if (strstr(buf, " vfpv3 ")) *hwcap |= HWCAP_VFPv3; if (strstr(buf, " neon ") || strstr(buf, " asimd ")) *hwcap |= HWCAP_NEON; if (strstr(buf, " fp ")) // Listed on 64 bit ARMv8 kernels *hwcap |= HWCAP_VFP | HWCAP_VFPv3; break; } } fclose(f); return 0; } int ff_get_cpu_flags_arm(void) { int flags = CORE_CPU_FLAGS; uint32_t hwcap; if (get_hwcap(&hwcap) < 0) if (get_cpuinfo(&hwcap) < 0) return flags; #define check_cap(cap, flag) do { \ if (hwcap & HWCAP_ ## cap) \ flags |= AV_CPU_FLAG_ ## flag; \ } while (0) /* No flags explicitly indicate v6 or v6T2 so check others which imply support. */ check_cap(EDSP, ARMV5TE); check_cap(TLS, ARMV6); check_cap(THUMBEE, ARMV6T2); check_cap(VFP, VFP); check_cap(VFPv3, VFPV3); check_cap(NEON, NEON); /* The v6 checks above are not reliable so let higher flags trickle down. */ if (flags & (AV_CPU_FLAG_VFPV3 | AV_CPU_FLAG_NEON)) flags |= AV_CPU_FLAG_ARMV6T2; else /* Some functions use the 'setend' instruction which is deprecated on ARMv8 * and serializing on some ARMv7 cores. This ensures such functions * are only enabled on ARMv6. */ flags |= AV_CPU_FLAG_SETEND; if (flags & AV_CPU_FLAG_ARMV6T2) flags |= AV_CPU_FLAG_ARMV6; return flags; } #else int ff_get_cpu_flags_arm(void) { return AV_CPU_FLAG_ARMV5TE * HAVE_ARMV5TE | AV_CPU_FLAG_ARMV6 * HAVE_ARMV6 | AV_CPU_FLAG_ARMV6T2 * HAVE_ARMV6T2 | AV_CPU_FLAG_VFP * HAVE_VFP | AV_CPU_FLAG_VFPV3 * HAVE_VFPV3 | AV_CPU_FLAG_NEON * HAVE_NEON | AV_CPU_FLAG_SETEND * !(HAVE_NEON | HAVE_VFPV3); } #endif