mirror of
https://github.com/u-boot/u-boot.git
synced 2024-11-24 12:44:23 +08:00
99 lines
2.3 KiB
C
99 lines
2.3 KiB
C
/*
|
|
* (C) Copyright 2003
|
|
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
|
|
*
|
|
* See file CREDITS for list of people who contributed to this
|
|
* project.
|
|
*
|
|
* 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; either version 2 of
|
|
* the License, or (at your option) any later version.
|
|
*
|
|
* 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.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
* MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <asm/mipsregs.h>
|
|
|
|
static unsigned long timestamp;
|
|
|
|
/* how many counter cycles in a jiffy */
|
|
#define CYCLES_PER_JIFFY (CONFIG_SYS_MIPS_TIMER_FREQ + CONFIG_SYS_HZ / 2) / CONFIG_SYS_HZ
|
|
|
|
/*
|
|
* timer without interrupts
|
|
*/
|
|
|
|
int timer_init(void)
|
|
{
|
|
/* Set up the timer for the first expiration. */
|
|
timestamp = 0;
|
|
write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void reset_timer(void)
|
|
{
|
|
timestamp = 0;
|
|
write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
|
|
}
|
|
|
|
ulong get_timer(ulong base)
|
|
{
|
|
unsigned int count;
|
|
unsigned int expirelo = read_c0_compare();
|
|
|
|
/* Check to see if we have missed any timestamps. */
|
|
count = read_c0_count();
|
|
while ((count - expirelo) < 0x7fffffff) {
|
|
expirelo += CYCLES_PER_JIFFY;
|
|
timestamp++;
|
|
}
|
|
write_c0_compare(expirelo);
|
|
|
|
return (timestamp - base);
|
|
}
|
|
|
|
void set_timer(ulong t)
|
|
{
|
|
timestamp = t;
|
|
write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
|
|
}
|
|
|
|
void udelay(unsigned long usec)
|
|
{
|
|
unsigned int tmo;
|
|
|
|
tmo = read_c0_count() + (usec * (CONFIG_SYS_MIPS_TIMER_FREQ / 1000000));
|
|
while ((tmo - read_c0_count()) < 0x7fffffff)
|
|
/*NOP*/;
|
|
}
|
|
|
|
/*
|
|
* This function is derived from PowerPC code (read timebase as long long).
|
|
* On MIPS it just returns the timer value.
|
|
*/
|
|
unsigned long long get_ticks(void)
|
|
{
|
|
return get_timer(0);
|
|
}
|
|
|
|
/*
|
|
* This function is derived from PowerPC code (timebase clock frequency).
|
|
* On MIPS it returns the number of timer ticks per second.
|
|
*/
|
|
ulong get_tbclk(void)
|
|
{
|
|
return CONFIG_SYS_HZ;
|
|
}
|