71 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			71 lines
		
	
	
		
			1.4 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
 | |
|  * (C) Copyright 2003
 | |
|  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 | |
|  *
 | |
|  * SPDX-License-Identifier:	GPL-2.0+
 | |
|  */
 | |
| 
 | |
| #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. */
 | |
| 	write_c0_compare(read_c0_count() + CYCLES_PER_JIFFY);
 | |
| 
 | |
| 	return 0;
 | |
| }
 | |
| 
 | |
| 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 __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;
 | |
| }
 |