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/*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Marius Groeger <mgroeger@sysgo.de>
*
* (C) Copyright 2002
* Sysgo Real-Time Solutions, GmbH <www.elinos.com>
* Alex Zuepke <azu@sysgo.de>
*
* (C) Copyright 2002
* Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#ifdef CONFIG_S3C24X0
#include <asm/io.h>
#include <asm/arch/s3c24x0_cpu.h>
DECLARE_GLOBAL_DATA_PTR;
int timer_init(void)
{
struct s3c24x0_timers *timers = s3c24x0_get_base_timers();
ulong tmr;
/* use PWM Timer 4 because it has no output */
/* prescaler for Timer 4 is 16 */
writel(0x0f00, &timers->tcfg0);
if (gd->arch.tbu == 0) {
/*
* for 10 ms clock period @ PCLK with 4 bit divider = 1/2
* (default) and prescaler = 16. Should be 10390
* @33.25MHz and 15625 @ 50 MHz
*/
gd->arch.tbu = get_PCLK() / (2 * 16 * 100);
gd->arch.timer_rate_hz = get_PCLK() / (2 * 16);
}
/* load value for 10 ms timeout */
writel(gd->arch.tbu, &timers->tcntb4);
/* auto load, manual update of timer 4 */
tmr = (readl(&timers->tcon) & ~0x0700000) | 0x0600000;
writel(tmr, &timers->tcon);
/* auto load, start timer 4 */
tmr = (tmr & ~0x0700000) | 0x0500000;
writel(tmr, &timers->tcon);
gd->arch.lastinc = 0;
gd->arch.tbl = 0;
return 0;
}
/*
* timer without interrupts
*/
ulong get_timer(ulong base)
{
return get_timer_masked() - base;
}
void __udelay (unsigned long usec)
{
ulong tmo;
ulong start = get_ticks();
tmo = usec / 1000;
tmo *= (gd->arch.tbu * 100);
tmo /= 1000;
while ((ulong) (get_ticks() - start) < tmo)
/*NOP*/;
}
ulong get_timer_masked(void)
{
ulong tmr = get_ticks();
return tmr / (gd->arch.timer_rate_hz / CONFIG_SYS_HZ);
}
void udelay_masked(unsigned long usec)
{
ulong tmo;
ulong endtime;
signed long diff;
if (usec >= 1000) {
tmo = usec / 1000;
tmo *= (gd->arch.tbu * 100);
tmo /= 1000;
} else {
tmo = usec * (gd->arch.tbu * 100);
tmo /= (1000 * 1000);
}
endtime = get_ticks() + tmo;
do {
ulong now = get_ticks();
diff = endtime - now;
} while (diff >= 0);
}
/*
* This function is derived from PowerPC code (read timebase as long long).
* On ARM it just returns the timer value.
*/
unsigned long long get_ticks(void)
{
struct s3c24x0_timers *timers = s3c24x0_get_base_timers();
ulong now = readl(&timers->tcnto4) & 0xffff;
if (gd->arch.lastinc >= now) {
/* normal mode */
gd->arch.tbl += gd->arch.lastinc - now;
} else {
/* we have an overflow ... */
gd->arch.tbl += gd->arch.lastinc + gd->arch.tbu - now;
}
gd->arch.lastinc = now;
return gd->arch.tbl;
}
/*
* This function is derived from PowerPC code (timebase clock frequency).
* On ARM it returns the number of timer ticks per second.
*/
ulong get_tbclk(void)
{
return CONFIG_SYS_HZ;
}
/*
* reset the cpu by setting up the watchdog timer and let him time out
*/
void reset_cpu(ulong ignored)
{
struct s3c24x0_watchdog *watchdog;
watchdog = s3c24x0_get_base_watchdog();
/* Disable watchdog */
writel(0x0000, &watchdog->wtcon);
/* Initialize watchdog timer count register */
writel(0x0001, &watchdog->wtcnt);
/* Enable watchdog timer; assert reset at timer timeout */
writel(0x0021, &watchdog->wtcon);
while (1)
/* loop forever and wait for reset to happen */;
/*NOTREACHED*/
}
#endif /* CONFIG_S3C24X0 */
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