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/*
* (C) Copyright 2007
* Sascha Hauer, Pengutronix
*
* (C) Copyright 2009 Freescale Semiconductor
*
* 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>
#include <asm/arch/mx25-regs.h>
#define TIMER_BASE 0x53f90000 /* General purpose timer 1 */
/* General purpose timers registers */
#define GPTCR __REG(TIMER_BASE) /* Control register */
#define GPTPR __REG(TIMER_BASE + 0x4) /* Prescaler register */
#define GPTSR __REG(TIMER_BASE + 0x8) /* Status register */
#define GPTCNT __REG(TIMER_BASE + 0x24) /* Counter register */
/* General purpose timers bitfields */
#define GPTCR_SWR (1<<15) /* Software reset */
#define GPTCR_FRR (1<<9) /* Freerun / restart */
#define GPTCR_CLKSOURCE_32 (4<<6) /* Clock source */
#define GPTCR_TEN (1) /* Timer enable */
static ulong timestamp;
static ulong lastinc;
static inline void setup_gpt()
{
int i;
static int init_done;
if (init_done)
return;
init_done = 1;
/* setup GP Timer 1 */
GPTCR = GPTCR_SWR;
for (i = 0; i < 100; i++)
GPTCR = 0; /* We have no udelay by now */
GPTPR = 0; /* 32Khz */
/* Freerun Mode, PERCLK1 input */
GPTCR |= GPTCR_CLKSOURCE_32 | GPTCR_TEN;
}
/* nothing really to do with interrupts, just starts up a counter. */
int timer_init(void)
{
setup_gpt();
return 0;
}
void reset_timer_masked(void)
{
/* reset time */
lastinc = GPTCNT; /* capture current incrementer value time */
timestamp = 0; /* start "advancing" time stamp from 0 */
}
void reset_timer(void)
{
reset_timer_masked();
}
ulong get_timer_masked(void)
{
ulong now = GPTCNT; /* current tick value */
if (now >= lastinc) /* normal mode (non roll) */
/* move stamp forward with absolut diff ticks */
timestamp += (now - lastinc);
else /* we have rollover of incrementer */
timestamp += (0xFFFFFFFF - lastinc) + now;
lastinc = now;
return timestamp;
}
ulong get_timer(ulong base)
{
return get_timer_masked() - base;
}
void set_timer(ulong t)
{
}
/* delay x useconds AND perserve advance timstamp value */
void udelay(unsigned long usec)
{
ulong tmo, tmp;
setup_gpt();
if (usec >= 1000) { /* if "big" number, spread normalize to secs */
tmo = usec / 1000; /* normalize usec to ticks per sec */
tmo *= CONFIG_SYS_HZ; /* find number of "ticks" to wait */
tmo /= 1000; /* finish normalize. */
} else { /* don't kill prior to HZ multiply */
tmo = usec * CONFIG_SYS_HZ;
tmo /= (1000*1000);
}
tmp = get_timer(0); /* get current timestamp */
if ((tmo + tmp + 1) < tmp) /* if overflow time stamp */
reset_timer_masked(); /* reset "advancing" timestamp to 0 */
else
tmo += tmp; /* else, set stamp wake up time */
while (get_timer_masked() < tmo)/* loop till event */
/*NOP*/;
}
void reset_cpu(ulong addr)
{
__REG16(WDOG_BASE) = 4;
}
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