ffmpeg/libavutil/aarch64/timer.h
Martin Storsjö ee040a7fc2 arm/aarch64: Use mach_absolute_time as timer on apple platforms
This is much less precise than the cycle counter register, but
the cycle counter register is not available on apple platforms
(and on linux, it requires a kernel module for allowing user mode
access).

Signed-off-by: Martin Storsjö <martin@martin.st>
2021-02-21 22:41:34 +02:00

51 lines
1.4 KiB
C

/*
* Copyright (c) 2015 Janne Grunau <janne-libav@jannau.net>
*
* 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
*/
#ifndef AVUTIL_AARCH64_TIMER_H
#define AVUTIL_AARCH64_TIMER_H
#include <stdint.h>
#include "config.h"
#if defined(__APPLE__)
#include <mach/mach_time.h>
#define AV_READ_TIME mach_absolute_time
#elif HAVE_INLINE_ASM
#define AV_READ_TIME read_time
static inline uint64_t read_time(void)
{
uint64_t cycle_counter;
__asm__ volatile(
"isb \t\n"
"mrs %0, pmccntr_el0 "
: "=r"(cycle_counter) :: "memory" );
return cycle_counter;
}
#endif /* HAVE_INLINE_ASM */
#endif /* AVUTIL_AARCH64_TIMER_H */