mirror of https://gitee.com/openkylin/linux.git
113 lines
2.4 KiB
C
113 lines
2.4 KiB
C
/*
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* linux/arch/arm/mach-footbridge/dc21285-timer.c
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*
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* Copyright (C) 1998 Russell King.
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* Copyright (C) 1998 Phil Blundell
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*/
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#include <linux/clockchips.h>
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#include <linux/clocksource.h>
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#include <linux/init.h>
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#include <linux/interrupt.h>
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#include <linux/irq.h>
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#include <asm/irq.h>
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#include <asm/hardware/dec21285.h>
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#include <asm/mach/time.h>
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#include "common.h"
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static cycle_t cksrc_dc21285_read(struct clocksource *cs)
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{
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return cs->mask - *CSR_TIMER2_VALUE;
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}
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static int cksrc_dc21285_enable(struct clocksource *cs)
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{
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*CSR_TIMER2_LOAD = cs->mask;
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*CSR_TIMER2_CLR = 0;
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*CSR_TIMER2_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_DIV16;
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return 0;
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}
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static int cksrc_dc21285_disable(struct clocksource *cs)
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{
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*CSR_TIMER2_CNTL = 0;
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}
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static struct clocksource cksrc_dc21285 = {
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.name = "dc21285_timer2",
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.rating = 200,
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.read = cksrc_dc21285_read,
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.enable = cksrc_dc21285_enable,
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.disable = cksrc_dc21285_disable,
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.mask = CLOCKSOURCE_MASK(24),
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.flags = CLOCK_SOURCE_IS_CONTINUOUS,
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};
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static void ckevt_dc21285_set_mode(enum clock_event_mode mode,
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struct clock_event_device *c)
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{
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switch (mode) {
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case CLOCK_EVT_MODE_RESUME:
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case CLOCK_EVT_MODE_PERIODIC:
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*CSR_TIMER1_CLR = 0;
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*CSR_TIMER1_LOAD = (mem_fclk_21285 + 8 * HZ) / (16 * HZ);
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*CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD |
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TIMER_CNTL_DIV16;
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break;
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default:
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*CSR_TIMER1_CNTL = 0;
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break;
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}
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}
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static struct clock_event_device ckevt_dc21285 = {
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.name = "dc21285_timer1",
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.features = CLOCK_EVT_FEAT_PERIODIC,
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.rating = 200,
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.irq = IRQ_TIMER1,
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.set_mode = ckevt_dc21285_set_mode,
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};
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static irqreturn_t timer1_interrupt(int irq, void *dev_id)
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{
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struct clock_event_device *ce = dev_id;
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*CSR_TIMER1_CLR = 0;
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ce->event_handler(ce);
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return IRQ_HANDLED;
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}
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static struct irqaction footbridge_timer_irq = {
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.name = "dc21285_timer1",
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.handler = timer1_interrupt,
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.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
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.dev_id = &ckevt_dc21285,
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};
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/*
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* Set up timer interrupt.
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*/
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static void __init footbridge_timer_init(void)
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{
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struct clock_event_device *ce = &ckevt_dc21285;
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clocksource_register_hz(&cksrc_dc21285, (mem_fclk_21285 + 8) / 16);
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setup_irq(ce->irq, &footbridge_timer_irq);
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clockevents_calc_mult_shift(ce, mem_fclk_21285, 5);
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ce->max_delta_ns = clockevent_delta2ns(0xffffff, ce);
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ce->min_delta_ns = clockevent_delta2ns(0x000004, ce);
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clockevents_register_device(ce);
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}
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struct sys_timer footbridge_timer = {
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.init = footbridge_timer_init,
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};
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