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