u-boot/arch/arm/cpu/pxa/timer.c
Marek Vasut d1bb9443f0 PXA: Replace timer driver
This new timer driver shall conform to new Timer API.

Signed-off-by: Marek Vasut <marek.vasut@gmail.com>
2011-12-06 23:59:32 +01:00

96 lines
2.2 KiB
C

/*
* Marvell PXA2xx/3xx timer driver
*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
*
* 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 <asm/arch/pxa-regs.h>
#include <asm/io.h>
#include <common.h>
#include <div64.h>
DECLARE_GLOBAL_DATA_PTR;
#define TIMER_LOAD_VAL 0xffffffff
#define timestamp (gd->tbl)
#define lastinc (gd->lastinc)
#if defined(CONFIG_CPU_PXA27X) || defined(CONFIG_CPU_MONAHANS)
#define TIMER_FREQ_HZ 3250000
#elif defined(CONFIG_CPU_PXA25X)
#define TIMER_FREQ_HZ 3686400
#else
#error "Timer frequency unknown - please config PXA CPU type"
#endif
static unsigned long long tick_to_time(unsigned long long tick)
{
return tick * CONFIG_SYS_HZ / TIMER_FREQ_HZ;
}
static unsigned long long us_to_tick(unsigned long long us)
{
return (us * TIMER_FREQ_HZ) / 1000000;
}
int timer_init(void)
{
writel(0, OSCR);
return 0;
}
unsigned long long get_ticks(void)
{
/* Current tick value */
uint32_t now = readl(OSCR);
if (now >= lastinc) {
/*
* Normal mode (non roll)
* Move stamp forward with absolute diff ticks
*/
timestamp += (now - lastinc);
} else {
/* We have rollover of incrementer */
timestamp += (TIMER_LOAD_VAL - lastinc) + now;
}
lastinc = now;
return timestamp;
}
ulong get_timer(ulong base)
{
return tick_to_time(get_ticks()) - base;
}
void __udelay(unsigned long usec)
{
unsigned long long tmp;
ulong tmo;
tmo = us_to_tick(usec);
tmp = get_ticks() + tmo; /* get current timestamp */
while (get_ticks() < tmp) /* loop till event */
/*NOP*/;
}