mirror of
				https://github.com/smaeul/u-boot.git
				synced 2025-11-03 21:48:15 +00:00 
			
		
		
		
	This reverts commit 65ba7add0d609bbd035b8d42fafdaf428ac24751. A weak extern is a nasty sight to behold: If the symbol is never defined, on ARM, the linker will replace the function call with a NOP. This behavior isn't well documented but there are at least some hints to it [1]. When timer_read_counter() is not defined, this obviously does the wrong thing here and it does so silently. The consequence is that a board without timer_read_counter() will sleep for random amounts and generally have erratic get_ticks() values. Drop the __weak annotation of the extern so a linker error is raised when timer_read_counter() is not defined. This is okay, the original reason for the reverted change - breaking the sandbox build - no longer applies. Final sidenote: This was the only weak extern in the entire tree at this time as far as I can tell. I guess we should avoid introduction of them again as they are obviously a very big footgun. [1]: https://stackoverflow.com/questions/31203402/gcc-behavior-for-unresolved-weak-functions Fixes: 65ba7add0d60 ("time: add weak annotation to timer_read_counter declaration") Reported-by: Serge Bazanski <q3k@q3k.org> Signed-off-by: Harald Seiler <hws@denx.de>
		
			
				
	
	
		
			207 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			207 lines
		
	
	
		
			3.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0+
 | 
						|
/*
 | 
						|
 * (C) Copyright 2000-2009
 | 
						|
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 | 
						|
 */
 | 
						|
 | 
						|
#include <common.h>
 | 
						|
#include <clock_legacy.h>
 | 
						|
#include <bootstage.h>
 | 
						|
#include <dm.h>
 | 
						|
#include <errno.h>
 | 
						|
#include <init.h>
 | 
						|
#include <spl.h>
 | 
						|
#include <time.h>
 | 
						|
#include <timer.h>
 | 
						|
#include <watchdog.h>
 | 
						|
#include <div64.h>
 | 
						|
#include <asm/global_data.h>
 | 
						|
#include <asm/io.h>
 | 
						|
#include <linux/delay.h>
 | 
						|
 | 
						|
#ifndef CONFIG_WD_PERIOD
 | 
						|
# define CONFIG_WD_PERIOD	(10 * 1000 * 1000)	/* 10 seconds default */
 | 
						|
#endif
 | 
						|
 | 
						|
DECLARE_GLOBAL_DATA_PTR;
 | 
						|
 | 
						|
#ifdef CFG_SYS_TIMER_RATE
 | 
						|
/* Returns tick rate in ticks per second */
 | 
						|
ulong notrace get_tbclk(void)
 | 
						|
{
 | 
						|
	return CFG_SYS_TIMER_RATE;
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
#ifdef CFG_SYS_TIMER_COUNTER
 | 
						|
unsigned long notrace timer_read_counter(void)
 | 
						|
{
 | 
						|
#ifdef CONFIG_SYS_TIMER_COUNTS_DOWN
 | 
						|
	return ~readl(CFG_SYS_TIMER_COUNTER);
 | 
						|
#else
 | 
						|
	return readl(CFG_SYS_TIMER_COUNTER);
 | 
						|
#endif
 | 
						|
}
 | 
						|
 | 
						|
ulong timer_get_boot_us(void)
 | 
						|
{
 | 
						|
	ulong count = timer_read_counter();
 | 
						|
 | 
						|
#ifdef CFG_SYS_TIMER_RATE
 | 
						|
	const ulong timer_rate = CFG_SYS_TIMER_RATE;
 | 
						|
 | 
						|
	if (timer_rate == 1000000)
 | 
						|
		return count;
 | 
						|
	else if (timer_rate > 1000000)
 | 
						|
		return lldiv(count, timer_rate / 1000000);
 | 
						|
	else
 | 
						|
		return (unsigned long long)count * 1000000 / timer_rate;
 | 
						|
#else
 | 
						|
	/* Assume the counter is in microseconds */
 | 
						|
	return count;
 | 
						|
#endif
 | 
						|
}
 | 
						|
 | 
						|
#else
 | 
						|
extern unsigned long timer_read_counter(void);
 | 
						|
#endif
 | 
						|
 | 
						|
#if CONFIG_IS_ENABLED(TIMER)
 | 
						|
ulong notrace get_tbclk(void)
 | 
						|
{
 | 
						|
	if (!gd->timer) {
 | 
						|
#ifdef CONFIG_TIMER_EARLY
 | 
						|
		return timer_early_get_rate();
 | 
						|
#else
 | 
						|
		int ret;
 | 
						|
 | 
						|
		ret = dm_timer_init();
 | 
						|
		if (ret)
 | 
						|
			return ret;
 | 
						|
#endif
 | 
						|
	}
 | 
						|
 | 
						|
	return timer_get_rate(gd->timer);
 | 
						|
}
 | 
						|
 | 
						|
uint64_t notrace get_ticks(void)
 | 
						|
{
 | 
						|
	u64 count;
 | 
						|
	int ret;
 | 
						|
 | 
						|
	if (!gd->timer) {
 | 
						|
#ifdef CONFIG_TIMER_EARLY
 | 
						|
		return timer_early_get_count();
 | 
						|
#else
 | 
						|
		int ret;
 | 
						|
 | 
						|
		ret = dm_timer_init();
 | 
						|
		if (ret)
 | 
						|
			panic("Could not initialize timer (err %d)\n", ret);
 | 
						|
#endif
 | 
						|
	}
 | 
						|
 | 
						|
	ret = timer_get_count(gd->timer, &count);
 | 
						|
	if (ret) {
 | 
						|
		if (spl_phase() > PHASE_TPL)
 | 
						|
			panic("Could not read count from timer (err %d)\n",
 | 
						|
			      ret);
 | 
						|
		else
 | 
						|
			panic("no timer (err %d)\n", ret);
 | 
						|
	}
 | 
						|
 | 
						|
	return count;
 | 
						|
}
 | 
						|
 | 
						|
#else /* !CONFIG_TIMER */
 | 
						|
 | 
						|
uint64_t __weak notrace get_ticks(void)
 | 
						|
{
 | 
						|
	unsigned long now = timer_read_counter();
 | 
						|
 | 
						|
	/* increment tbu if tbl has rolled over */
 | 
						|
	if (now < gd->timebase_l)
 | 
						|
		gd->timebase_h++;
 | 
						|
	gd->timebase_l = now;
 | 
						|
	return ((uint64_t)gd->timebase_h << 32) | gd->timebase_l;
 | 
						|
}
 | 
						|
 | 
						|
#endif /* CONFIG_TIMER */
 | 
						|
 | 
						|
/* Returns time in milliseconds */
 | 
						|
static uint64_t notrace tick_to_time(uint64_t tick)
 | 
						|
{
 | 
						|
	ulong div = get_tbclk();
 | 
						|
 | 
						|
	tick *= CONFIG_SYS_HZ;
 | 
						|
	do_div(tick, div);
 | 
						|
	return tick;
 | 
						|
}
 | 
						|
 | 
						|
int __weak timer_init(void)
 | 
						|
{
 | 
						|
	return 0;
 | 
						|
}
 | 
						|
 | 
						|
/* Returns time in milliseconds */
 | 
						|
ulong __weak get_timer(ulong base)
 | 
						|
{
 | 
						|
	return tick_to_time(get_ticks()) - base;
 | 
						|
}
 | 
						|
 | 
						|
static uint64_t notrace tick_to_time_us(uint64_t tick)
 | 
						|
{
 | 
						|
	ulong div = get_tbclk() / 1000;
 | 
						|
 | 
						|
	tick *= CONFIG_SYS_HZ;
 | 
						|
	do_div(tick, div);
 | 
						|
	return tick;
 | 
						|
}
 | 
						|
 | 
						|
uint64_t __weak get_timer_us(uint64_t base)
 | 
						|
{
 | 
						|
	return tick_to_time_us(get_ticks()) - base;
 | 
						|
}
 | 
						|
 | 
						|
unsigned long __weak get_timer_us_long(unsigned long base)
 | 
						|
{
 | 
						|
	return timer_get_us() - base;
 | 
						|
}
 | 
						|
 | 
						|
unsigned long __weak notrace timer_get_us(void)
 | 
						|
{
 | 
						|
	return tick_to_time(get_ticks() * 1000);
 | 
						|
}
 | 
						|
 | 
						|
uint64_t usec_to_tick(unsigned long usec)
 | 
						|
{
 | 
						|
	uint64_t tick = usec;
 | 
						|
	tick *= get_tbclk();
 | 
						|
	do_div(tick, 1000000);
 | 
						|
	return tick;
 | 
						|
}
 | 
						|
 | 
						|
void __weak __udelay(unsigned long usec)
 | 
						|
{
 | 
						|
	uint64_t tmp;
 | 
						|
 | 
						|
	tmp = get_ticks() + usec_to_tick(usec);	/* get current timestamp */
 | 
						|
 | 
						|
	while (get_ticks() < tmp+1)	/* loop till event */
 | 
						|
		 /*NOP*/;
 | 
						|
}
 | 
						|
 | 
						|
/* ------------------------------------------------------------------------- */
 | 
						|
 | 
						|
void udelay(unsigned long usec)
 | 
						|
{
 | 
						|
	ulong kv;
 | 
						|
 | 
						|
	do {
 | 
						|
		schedule();
 | 
						|
		kv = usec > CONFIG_WD_PERIOD ? CONFIG_WD_PERIOD : usec;
 | 
						|
		__udelay(kv);
 | 
						|
		usec -= kv;
 | 
						|
	} while(usec);
 | 
						|
}
 |