hpcorebootfe80/payloads/libpayload/drivers/timer/img_pistachio.c

39 lines
1.1 KiB
C

/*
* This file is part of the libpayload project.
*
* Copyright (C) 2014 Imagination Technologies
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* This program 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 General Public License for more details.
*/
#include <libpayload.h>
#include <arch/cpu.h>
uint64_t timer_hz(void)
{
return lib_sysinfo.cpu_khz * 1000;
}
uint64_t timer_raw_value(void)
{
static uint64_t total_ticks = 0;
uint8_t overflow = 0;
uint32_t current_ticks = read_c0_count() * 2;
/* It assumes only one overflow happened since the last call */
if (current_ticks <= (uint32_t)total_ticks)
overflow = 1;
/* The least significant part(32 bits) of total_ticks will always
* become equal to current ticks */
total_ticks = (((total_ticks >> 32) + overflow) << 32) +
current_ticks;
return total_ticks;
}