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linux-next/arch/arm/plat-iop/time.c
Linus Torvalds 0cd61b68c3 Initial blind fixup for arm for irq changes
Untested, but this should fix up the bulk of the totally mechanical
issues, and should make the actual detail fixing easier.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-06 10:59:54 -07:00

99 lines
2.4 KiB
C

/*
* arch/arm/plat-iop/time.c
*
* Timer code for IOP32x and IOP33x based systems
*
* Author: Deepak Saxena <dsaxena@mvista.com>
*
* Copyright 2002-2003 MontaVista Software Inc.
*
* 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.
*/
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/timex.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
#ifdef CONFIG_ARCH_IOP32X
#define IRQ_IOP3XX_TIMER0 IRQ_IOP32X_TIMER0
#else
#ifdef CONFIG_ARCH_IOP33X
#define IRQ_IOP3XX_TIMER0 IRQ_IOP33X_TIMER0
#endif
#endif
static unsigned long ticks_per_jiffy;
static unsigned long ticks_per_usec;
static unsigned long next_jiffy_time;
unsigned long iop3xx_gettimeoffset(void)
{
unsigned long offset;
offset = next_jiffy_time - *IOP3XX_TU_TCR1;
return offset / ticks_per_usec;
}
static irqreturn_t
iop3xx_timer_interrupt(int irq, void *dev_id)
{
write_seqlock(&xtime_lock);
iop3xx_cp6_enable();
asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (1));
iop3xx_cp6_disable();
while ((signed long)(next_jiffy_time - *IOP3XX_TU_TCR1)
>= ticks_per_jiffy) {
timer_tick();
next_jiffy_time -= ticks_per_jiffy;
}
write_sequnlock(&xtime_lock);
return IRQ_HANDLED;
}
static struct irqaction iop3xx_timer_irq = {
.name = "IOP3XX Timer Tick",
.handler = iop3xx_timer_interrupt,
.flags = IRQF_DISABLED | IRQF_TIMER,
};
void __init iop3xx_init_time(unsigned long tick_rate)
{
u32 timer_ctl;
ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
ticks_per_usec = tick_rate / 1000000;
next_jiffy_time = 0xffffffff;
timer_ctl = IOP3XX_TMR_EN | IOP3XX_TMR_PRIVILEGED |
IOP3XX_TMR_RELOAD | IOP3XX_TMR_RATIO_1_1;
/*
* We use timer 0 for our timer interrupt, and timer 1 as
* monotonic counter for tracking missed jiffies.
*/
iop3xx_cp6_enable();
asm volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (ticks_per_jiffy - 1));
asm volatile("mcr p6, 0, %0, c0, c1, 0" : : "r" (timer_ctl));
asm volatile("mcr p6, 0, %0, c5, c1, 0" : : "r" (0xffffffff));
asm volatile("mcr p6, 0, %0, c1, c1, 0" : : "r" (timer_ctl));
iop3xx_cp6_disable();
setup_irq(IRQ_IOP3XX_TIMER0, &iop3xx_timer_irq);
}