linux-sg2042/arch/mips/kernel/cevt-txx9.c

172 lines
4.9 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Based on linux/arch/mips/kernel/cevt-r4k.c,
* linux/arch/mips/jmr3927/rbhma3100/setup.c
*
* Copyright 2001 MontaVista Software Inc.
* Copyright (C) 2000-2001 Toshiba Corporation
* Copyright (C) 2007 MIPS Technologies, Inc.
* Copyright (C) 2007 Ralf Baechle <ralf@linux-mips.org>
*/
#include <linux/init.h>
#include <linux/interrupt.h>
#include <asm/time.h>
#include <asm/txx9tmr.h>
#define TCR_BASE (TXx9_TMTCR_CCDE | TXx9_TMTCR_CRE | TXx9_TMTCR_TMODE_ITVL)
#define TIMER_CCD 0 /* 1/2 */
#define TIMER_CLK(imclk) ((imclk) / (2 << TIMER_CCD))
static struct txx9_tmr_reg __iomem *txx9_cs_tmrptr;
static cycle_t txx9_cs_read(void)
{
return __raw_readl(&txx9_cs_tmrptr->trr);
}
/* Use 1 bit smaller width to use full bits in that width */
#define TXX9_CLOCKSOURCE_BITS (TXX9_TIMER_BITS - 1)
static struct clocksource txx9_clocksource = {
.name = "TXx9",
.rating = 200,
.read = txx9_cs_read,
.mask = CLOCKSOURCE_MASK(TXX9_CLOCKSOURCE_BITS),
.flags = CLOCK_SOURCE_IS_CONTINUOUS,
};
void __init txx9_clocksource_init(unsigned long baseaddr,
unsigned int imbusclk)
{
struct txx9_tmr_reg __iomem *tmrptr;
clocksource_set_clock(&txx9_clocksource, TIMER_CLK(imbusclk));
clocksource_register(&txx9_clocksource);
tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
__raw_writel(TCR_BASE, &tmrptr->tcr);
__raw_writel(0, &tmrptr->tisr);
__raw_writel(TIMER_CCD, &tmrptr->ccdr);
__raw_writel(TXx9_TMITMR_TZCE, &tmrptr->itmr);
__raw_writel(1 << TXX9_CLOCKSOURCE_BITS, &tmrptr->cpra);
__raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
txx9_cs_tmrptr = tmrptr;
}
static struct txx9_tmr_reg __iomem *txx9_tmrptr;
static void txx9tmr_stop_and_clear(struct txx9_tmr_reg __iomem *tmrptr)
{
/* stop and reset counter */
__raw_writel(TCR_BASE, &tmrptr->tcr);
/* clear pending interrupt */
__raw_writel(0, &tmrptr->tisr);
}
static void txx9tmr_set_mode(enum clock_event_mode mode,
struct clock_event_device *evt)
{
struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
txx9tmr_stop_and_clear(tmrptr);
switch (mode) {
case CLOCK_EVT_MODE_PERIODIC:
__raw_writel(TXx9_TMITMR_TIIE | TXx9_TMITMR_TZCE,
&tmrptr->itmr);
/* start timer */
__raw_writel(((u64)(NSEC_PER_SEC / HZ) * evt->mult) >>
evt->shift,
&tmrptr->cpra);
__raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
break;
case CLOCK_EVT_MODE_SHUTDOWN:
case CLOCK_EVT_MODE_UNUSED:
__raw_writel(0, &tmrptr->itmr);
break;
case CLOCK_EVT_MODE_ONESHOT:
__raw_writel(TXx9_TMITMR_TIIE, &tmrptr->itmr);
break;
case CLOCK_EVT_MODE_RESUME:
__raw_writel(TIMER_CCD, &tmrptr->ccdr);
__raw_writel(0, &tmrptr->itmr);
break;
}
}
static int txx9tmr_set_next_event(unsigned long delta,
struct clock_event_device *evt)
{
struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
txx9tmr_stop_and_clear(tmrptr);
/* start timer */
__raw_writel(delta, &tmrptr->cpra);
__raw_writel(TCR_BASE | TXx9_TMTCR_TCE, &tmrptr->tcr);
return 0;
}
static struct clock_event_device txx9tmr_clock_event_device = {
.name = "TXx9",
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
.rating = 200,
.cpumask = CPU_MASK_CPU0,
.set_mode = txx9tmr_set_mode,
.set_next_event = txx9tmr_set_next_event,
};
static irqreturn_t txx9tmr_interrupt(int irq, void *dev_id)
{
struct clock_event_device *cd = &txx9tmr_clock_event_device;
struct txx9_tmr_reg __iomem *tmrptr = txx9_tmrptr;
__raw_writel(0, &tmrptr->tisr); /* ack interrupt */
cd->event_handler(cd);
return IRQ_HANDLED;
}
static struct irqaction txx9tmr_irq = {
.handler = txx9tmr_interrupt,
.flags = IRQF_DISABLED | IRQF_PERCPU,
.name = "txx9tmr",
};
void __init txx9_clockevent_init(unsigned long baseaddr, int irq,
unsigned int imbusclk)
{
struct clock_event_device *cd = &txx9tmr_clock_event_device;
struct txx9_tmr_reg __iomem *tmrptr;
tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
txx9tmr_stop_and_clear(tmrptr);
__raw_writel(TIMER_CCD, &tmrptr->ccdr);
__raw_writel(0, &tmrptr->itmr);
txx9_tmrptr = tmrptr;
clockevent_set_clock(cd, TIMER_CLK(imbusclk));
cd->max_delta_ns =
clockevent_delta2ns(0xffffffff >> (32 - TXX9_TIMER_BITS), cd);
cd->min_delta_ns = clockevent_delta2ns(0xf, cd);
cd->irq = irq;
clockevents_register_device(cd);
setup_irq(irq, &txx9tmr_irq);
printk(KERN_INFO "TXx9: clockevent device at 0x%lx, irq %d\n",
baseaddr, irq);
}
void __init txx9_tmr_init(unsigned long baseaddr)
{
struct txx9_tmr_reg __iomem *tmrptr;
tmrptr = ioremap(baseaddr, sizeof(struct txx9_tmr_reg));
__raw_writel(TXx9_TMTCR_CRE, &tmrptr->tcr);
__raw_writel(0, &tmrptr->tisr);
__raw_writel(0xffffffff, &tmrptr->cpra);
__raw_writel(0, &tmrptr->itmr);
__raw_writel(0, &tmrptr->ccdr);
__raw_writel(0, &tmrptr->pgmr);
iounmap(tmrptr);
}