u-boot/cpu/pxa/interrupts.c
Jean-Christophe PLAGNIOL-VILLARD a922fdb87a PXA: timer use do_div and simplify it
Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
2009-03-09 12:01:32 +01:00

127 lines
2.7 KiB
C

/*
* (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>
*
* 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/pxa-regs.h>
#include <div64.h>
#ifdef CONFIG_USE_IRQ
#error: interrupts not implemented yet
#endif
#if defined(CONFIG_PXA27X) || defined(CONFIG_CPU_MONAHANS)
#define TIMER_FREQ_HZ 3250000
#elif defined(CONFIG_PXA250)
#define TIMER_FREQ_HZ 3686400
#else
#error "Timer frequency unknown - please config PXA CPU type"
#endif
static inline unsigned long long tick_to_time(unsigned long long tick)
{
tick *= CONFIG_SYS_HZ;
do_div(tick, TIMER_FREQ_HZ);
return tick;
}
static inline unsigned long long us_to_tick(unsigned long long us)
{
us = us * TIMER_FREQ_HZ + 999999;
do_div(us, 1000000);
return us;
}
int interrupt_init (void)
{
/* nothing happens here - we don't setup any IRQs */
return (0);
}
void reset_timer (void)
{
reset_timer_masked ();
}
ulong get_timer (ulong base)
{
return get_timer_masked () - base;
}
void set_timer (ulong t)
{
/* nop */
}
void udelay (unsigned long usec)
{
udelay_masked (usec);
}
void reset_timer_masked (void)
{
OSCR = 0;
}
ulong get_timer_masked (void)
{
return tick_to_time(get_ticks());
}
void udelay_masked (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*/;
}
/*
* 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)
{
return OSCR;
}
/*
* 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;
tbclk = TIMER_FREQ_HZ;
return tbclk;
}