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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>
*
* 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>
#ifdef CONFIG_S3C24X0
#include <asm/io.h>
#include <asm/arch/s3c24x0_cpu.h>
int timer_load_val = 0;
static ulong timer_clk;
/* macro to read the 16 bit timer */
static inline ulong READ_TIMER(void)
{
struct s3c24x0_timers *timers = s3c24x0_get_base_timers();
return readl(&timers->tcnto4) & 0xffff;
}
static ulong timestamp;
static ulong lastdec;
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 (timer_load_val == 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
*/
timer_load_val = get_PCLK() / (2 * 16 * 100);
timer_clk = get_PCLK() / (2 * 16);
}
/* load value for 10 ms timeout */
lastdec = timer_load_val;
writel(timer_load_val, &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);
timestamp = 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 *= (timer_load_val * 100);
tmo /= 1000;
while ((ulong) (get_ticks() - start) < tmo)
/*NOP*/;
}
void reset_timer_masked(void)
{
/* reset time */
lastdec = READ_TIMER();
timestamp = 0;
}
ulong get_timer_masked(void)
{
ulong tmr = get_ticks();
return tmr / (timer_clk / CONFIG_SYS_HZ);
}
void udelay_masked(unsigned long usec)
{
ulong tmo;
ulong endtime;
signed long diff;
if (usec >= 1000) {
tmo = usec / 1000;
tmo *= (timer_load_val * 100);
tmo /= 1000;
} else {
tmo = usec * (timer_load_val * 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)
{
ulong now = READ_TIMER();
if (lastdec >= now) {
/* normal mode */
timestamp += lastdec - now;
} else {
/* we have an overflow ... */
timestamp += lastdec + timer_load_val - now;
}
lastdec = now;
return timestamp;
}
/*
* 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)
{
ulong tbclk;
#if defined(CONFIG_SMDK2400)
tbclk = timer_load_val * 100;
#elif defined(CONFIG_SBC2410X) || \
defined(CONFIG_SMDK2410) || \
defined(CONFIG_S3C2440) || \
defined(CONFIG_VCMA9)
tbclk = CONFIG_SYS_HZ;
#else
# error "tbclk not configured"
#endif
return tbclk;
}
/*
* 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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