mirror of
https://github.com/FFmpeg/FFmpeg.git
synced 2025-01-08 13:22:53 +02:00
0c0a3deb18
RVV defines a total of 12 different extensions, including: - 5 different instruction subsets: - Zve32x: 8-, 16- and 32-bit integers, - Zve32f: Zve32x plus single precision floats, - Zve64x: Zve32x plus 64-bit integers, - Zve64f: Zve32f plus Zve64x, - Zve64d: Zve64f plus double precision floats. - 6 different vector lengths: - Zvl32b (embedded only), - Zvl64b (embedded only), - Zvl128b, - Zvl256b, - Zvl512b, - Zvl1024b, - and the V extension proper: equivalent to Zve64f and Zvl128b. In total, there are 6 different possible sets of supported instructions (including the empty set), but for convenience we allocate one bit for each type sets: up-to-32-bit ints (RVV_I32), floats (RVV_F32), 64-bit ints (RVV_I64) and doubles (RVV_F64). Whence the vector size is needed, it can be retrieved by reading the unprivileged read-only vlenb CSR. This should probably be a separate helper macro if needed at a later point.
76 lines
2.1 KiB
C
76 lines
2.1 KiB
C
/*
|
|
* Copyright © 2022 Rémi Denis-Courmont.
|
|
*
|
|
* 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 "libavutil/log.h"
|
|
#include "config.h"
|
|
|
|
#if HAVE_GETAUXVAL
|
|
#include <sys/auxv.h>
|
|
#define HWCAP_RV(letter) (1ul << ((letter) - 'A'))
|
|
#endif
|
|
|
|
int ff_get_cpu_flags_riscv(void)
|
|
{
|
|
int ret = 0;
|
|
#if HAVE_GETAUXVAL
|
|
const unsigned long hwcap = getauxval(AT_HWCAP);
|
|
|
|
if (hwcap & HWCAP_RV('I'))
|
|
ret |= AV_CPU_FLAG_RVI;
|
|
if (hwcap & HWCAP_RV('F'))
|
|
ret |= AV_CPU_FLAG_RVF;
|
|
if (hwcap & HWCAP_RV('D'))
|
|
ret |= AV_CPU_FLAG_RVD;
|
|
|
|
/* The V extension implies all Zve* functional subsets */
|
|
if (hwcap & HWCAP_RV('V'))
|
|
ret |= AV_CPU_FLAG_RVV_I32 | AV_CPU_FLAG_RVV_I64
|
|
| AV_CPU_FLAG_RVV_F32 | AV_CPU_FLAG_RVV_F64;
|
|
#endif
|
|
|
|
#ifdef __riscv_i
|
|
ret |= AV_CPU_FLAG_RVI;
|
|
#endif
|
|
#if defined (__riscv_flen) && (__riscv_flen >= 32)
|
|
ret |= AV_CPU_FLAG_RVF;
|
|
#if (__riscv_flen >= 64)
|
|
ret |= AV_CPU_FLAG_RVD;
|
|
#endif
|
|
#endif
|
|
|
|
/* If RV-V is enabled statically at compile-time, check the details. */
|
|
#ifdef __riscv_vectors
|
|
ret |= AV_CPU_FLAG_RVV_I32;
|
|
#if __riscv_v_elen >= 64
|
|
ret |= AV_CPU_FLAG_RVV_I64;
|
|
#endif
|
|
#if __riscv_v_elen_fp >= 32
|
|
ret |= AV_CPU_FLAG_RVV_F32;
|
|
#if __riscv_v_elen_fp >= 64
|
|
ret |= AV_CPU_FLAG_RVV_F64;
|
|
#endif
|
|
#endif
|
|
#endif
|
|
|
|
return ret;
|
|
}
|