| 1 | /* |
| 2 | * This file is part of FFmpeg. |
| 3 | * |
| 4 | * FFmpeg is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU Lesser General Public |
| 6 | * License as published by the Free Software Foundation; either |
| 7 | * version 2.1 of the License, or (at your option) any later version. |
| 8 | * |
| 9 | * FFmpeg is distributed in the hope that it will be useful, |
| 10 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 12 | * Lesser General Public License for more details. |
| 13 | * |
| 14 | * You should have received a copy of the GNU Lesser General Public |
| 15 | * License along with FFmpeg; if not, write to the Free Software |
| 16 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 17 | */ |
| 18 | |
| 19 | #include "libavutil/cpu.h" |
| 20 | #include "libavutil/cpu_internal.h" |
| 21 | #include "config.h" |
| 22 | |
| 23 | #define CORE_FLAG(f) \ |
| 24 | (AV_CPU_FLAG_ ## f * (HAVE_ ## f ## _EXTERNAL || HAVE_ ## f ## _INLINE)) |
| 25 | |
| 26 | #define CORE_CPU_FLAGS \ |
| 27 | (CORE_FLAG(ARMV5TE) | \ |
| 28 | CORE_FLAG(ARMV6) | \ |
| 29 | CORE_FLAG(ARMV6T2) | \ |
| 30 | CORE_FLAG(VFP) | \ |
| 31 | CORE_FLAG(VFPV3) | \ |
| 32 | CORE_FLAG(NEON)) |
| 33 | |
| 34 | #if defined __linux__ || defined __ANDROID__ |
| 35 | |
| 36 | #include <stdint.h> |
| 37 | #include <stdio.h> |
| 38 | #include <string.h> |
| 39 | #include "libavutil/avstring.h" |
| 40 | |
| 41 | #define AT_HWCAP 16 |
| 42 | |
| 43 | /* Relevant HWCAP values from kernel headers */ |
| 44 | #define HWCAP_VFP (1 << 6) |
| 45 | #define HWCAP_EDSP (1 << 7) |
| 46 | #define HWCAP_THUMBEE (1 << 11) |
| 47 | #define HWCAP_NEON (1 << 12) |
| 48 | #define HWCAP_VFPv3 (1 << 13) |
| 49 | #define HWCAP_TLS (1 << 15) |
| 50 | |
| 51 | static int get_hwcap(uint32_t *hwcap) |
| 52 | { |
| 53 | struct { uint32_t a_type; uint32_t a_val; } auxv; |
| 54 | FILE *f = fopen("/proc/self/auxv", "r"); |
| 55 | int err = -1; |
| 56 | |
| 57 | if (!f) |
| 58 | return -1; |
| 59 | |
| 60 | while (fread(&auxv, sizeof(auxv), 1, f) > 0) { |
| 61 | if (auxv.a_type == AT_HWCAP) { |
| 62 | *hwcap = auxv.a_val; |
| 63 | err = 0; |
| 64 | break; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | fclose(f); |
| 69 | return err; |
| 70 | } |
| 71 | |
| 72 | static int get_cpuinfo(uint32_t *hwcap) |
| 73 | { |
| 74 | FILE *f = fopen("/proc/cpuinfo", "r"); |
| 75 | char buf[200]; |
| 76 | |
| 77 | if (!f) |
| 78 | return -1; |
| 79 | |
| 80 | *hwcap = 0; |
| 81 | while (fgets(buf, sizeof(buf), f)) { |
| 82 | if (av_strstart(buf, "Features", NULL)) { |
| 83 | if (strstr(buf, " edsp ")) |
| 84 | *hwcap |= HWCAP_EDSP; |
| 85 | if (strstr(buf, " tls ")) |
| 86 | *hwcap |= HWCAP_TLS; |
| 87 | if (strstr(buf, " thumbee ")) |
| 88 | *hwcap |= HWCAP_THUMBEE; |
| 89 | if (strstr(buf, " vfp ")) |
| 90 | *hwcap |= HWCAP_VFP; |
| 91 | if (strstr(buf, " vfpv3 ")) |
| 92 | *hwcap |= HWCAP_VFPv3; |
| 93 | if (strstr(buf, " neon ") || strstr(buf, " asimd ")) |
| 94 | *hwcap |= HWCAP_NEON; |
| 95 | if (strstr(buf, " fp ")) // Listed on 64 bit ARMv8 kernels |
| 96 | *hwcap |= HWCAP_VFP | HWCAP_VFPv3; |
| 97 | break; |
| 98 | } |
| 99 | } |
| 100 | fclose(f); |
| 101 | return 0; |
| 102 | } |
| 103 | |
| 104 | int ff_get_cpu_flags_arm(void) |
| 105 | { |
| 106 | int flags = CORE_CPU_FLAGS; |
| 107 | uint32_t hwcap; |
| 108 | |
| 109 | if (get_hwcap(&hwcap) < 0) |
| 110 | if (get_cpuinfo(&hwcap) < 0) |
| 111 | return flags; |
| 112 | |
| 113 | #define check_cap(cap, flag) do { \ |
| 114 | if (hwcap & HWCAP_ ## cap) \ |
| 115 | flags |= AV_CPU_FLAG_ ## flag; \ |
| 116 | } while (0) |
| 117 | |
| 118 | /* No flags explicitly indicate v6 or v6T2 so check others which |
| 119 | imply support. */ |
| 120 | check_cap(EDSP, ARMV5TE); |
| 121 | check_cap(TLS, ARMV6); |
| 122 | check_cap(THUMBEE, ARMV6T2); |
| 123 | check_cap(VFP, VFP); |
| 124 | check_cap(VFPv3, VFPV3); |
| 125 | check_cap(NEON, NEON); |
| 126 | |
| 127 | /* The v6 checks above are not reliable so let higher flags |
| 128 | trickle down. */ |
| 129 | if (flags & (AV_CPU_FLAG_VFPV3 | AV_CPU_FLAG_NEON)) |
| 130 | flags |= AV_CPU_FLAG_ARMV6T2; |
| 131 | else |
| 132 | /* Some functions use the 'setend' instruction which is deprecated on ARMv8 |
| 133 | * and serializing on some ARMv7 cores. This ensures such functions |
| 134 | * are only enabled on ARMv6. */ |
| 135 | flags |= AV_CPU_FLAG_SETEND; |
| 136 | |
| 137 | if (flags & AV_CPU_FLAG_ARMV6T2) |
| 138 | flags |= AV_CPU_FLAG_ARMV6; |
| 139 | |
| 140 | return flags; |
| 141 | } |
| 142 | |
| 143 | #else |
| 144 | |
| 145 | int ff_get_cpu_flags_arm(void) |
| 146 | { |
| 147 | return AV_CPU_FLAG_ARMV5TE * HAVE_ARMV5TE | |
| 148 | AV_CPU_FLAG_ARMV6 * HAVE_ARMV6 | |
| 149 | AV_CPU_FLAG_ARMV6T2 * HAVE_ARMV6T2 | |
| 150 | AV_CPU_FLAG_VFP * HAVE_VFP | |
| 151 | AV_CPU_FLAG_VFPV3 * HAVE_VFPV3 | |
| 152 | AV_CPU_FLAG_NEON * HAVE_NEON | |
| 153 | AV_CPU_FLAG_SETEND * !(HAVE_NEON | HAVE_VFPV3); |
| 154 | } |
| 155 | |
| 156 | #endif |