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	As I initially suspected overflow in time handling, I took a detailed look at lib/time.c. This adds comments about units being used, reduces amount of type casting being done, and makes __udelay() always wait at least one tick. (Current code could do no delaying at all for short delays). Signed-off-by: Pavel Machek <pavel@denx.de>
		
			
				
	
	
		
			118 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			118 lines
		
	
	
		
			2.3 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * (C) Copyright 2000-2009
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|  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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|  *
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|  * SPDX-License-Identifier:	GPL-2.0+
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|  */
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| 
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| #include <common.h>
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| #include <watchdog.h>
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| #include <div64.h>
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| #include <asm/io.h>
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| 
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| #if CONFIG_SYS_HZ != 1000
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| #warning "CONFIG_SYS_HZ must be 1000 and should not be defined by platforms"
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| #endif
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| 
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| #ifndef CONFIG_WD_PERIOD
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| # define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
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| #endif
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| 
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| DECLARE_GLOBAL_DATA_PTR;
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| 
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| #ifdef CONFIG_SYS_TIMER_RATE
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| /* Returns tick rate in ticks per second */
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| ulong notrace get_tbclk(void)
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| {
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| 	return CONFIG_SYS_TIMER_RATE;
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| }
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| #endif
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| 
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| #ifdef CONFIG_SYS_TIMER_COUNTER
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| unsigned long notrace timer_read_counter(void)
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| {
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| #ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
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| 	return ~readl(CONFIG_SYS_TIMER_COUNTER);
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| #else
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| 	return readl(CONFIG_SYS_TIMER_COUNTER);
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| #endif
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| }
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| #else
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| extern unsigned long __weak timer_read_counter(void);
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| #endif
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| 
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| unsigned long long __weak notrace get_ticks(void)
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| {
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| 	unsigned long now = timer_read_counter();
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| 
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| 	/* increment tbu if tbl has rolled over */
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| 	if (now < gd->timebase_l)
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| 		gd->timebase_h++;
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| 	gd->timebase_l = now;
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| 	return ((unsigned long long)gd->timebase_h << 32) | gd->timebase_l;
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| }
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| 
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| /* Returns time in milliseconds */
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| static unsigned long long notrace tick_to_time(unsigned long long tick)
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| {
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| 	ulong div = get_tbclk();
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| 
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| 	tick *= CONFIG_SYS_HZ;
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| 	do_div(tick, div);
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| 	return tick;
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| }
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| 
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| int __weak timer_init(void)
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| {
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| 	return 0;
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| }
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| 
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| /* Returns time in milliseconds */
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| ulong __weak get_timer(ulong base)
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| {
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| 	return tick_to_time(get_ticks()) - base;
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| }
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| 
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| unsigned long __weak notrace timer_get_us(void)
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| {
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| 	return tick_to_time(get_ticks() * 1000);
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| }
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| 
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| static unsigned long long usec_to_tick(unsigned long usec)
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| {
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| 	unsigned long long tick = usec;
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| 	tick *= get_tbclk();
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| 	do_div(tick, 1000000);
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| 	return tick;
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| }
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| 
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| void __weak __udelay(unsigned long usec)
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| {
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| 	unsigned long long tmp;
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| 
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| 	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
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| 
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| 	while (get_ticks() < tmp+1)	/* loop till event */
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| 		 /*NOP*/;
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| }
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| 
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| /* ------------------------------------------------------------------------- */
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| 
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| void udelay(unsigned long usec)
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| {
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| 	ulong kv;
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| 
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| 	do {
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| 		WATCHDOG_RESET();
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| 		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
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| 		__udelay (kv);
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| 		usec -= kv;
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| 	} while(usec);
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| }
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| 
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| void mdelay(unsigned long msec)
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| {
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| 	while (msec--)
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| 		udelay(1000);
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| }
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