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/*
* linux/arch/arm/mach-w90x900/time.c
*
* Based on linux/arch/arm/plat-s3c24xx/time.c by Ben Dooks
*
* Copyright (c) 2009 Nuvoton technology corporation
* All rights reserved.
*
* Wan ZongShun <mcuos.com@gmail.com>
*
* 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/sched.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/leds.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <asm/mach-types.h>
#include <asm/mach/irq.h>
#include <asm/mach/time.h>
#include <mach/map.h>
#include "regs-timer.h"
#include "nuc9xx.h"
#define RESETINT 0x1f
#define PERIOD (0x01 << 27)
#define ONESHOT (0x00 << 27)
#define COUNTEN (0x01 << 30)
#define INTEN (0x01 << 29)
#define TICKS_PER_SEC 100
#define PRESCALE 0x63 /* Divider = prescale + 1 */
#define TDR_SHIFT 24
static unsigned int timer0_load;
static int nuc900_clockevent_shutdown(struct clock_event_device *evt)
{
unsigned int val = __raw_readl(REG_TCSR0) & ~(0x03 << 27);
__raw_writel(val, REG_TCSR0);
return 0;
}
static int nuc900_clockevent_set_oneshot(struct clock_event_device *evt)
{
unsigned int val = __raw_readl(REG_TCSR0) & ~(0x03 << 27);
val |= (ONESHOT | COUNTEN | INTEN | PRESCALE);
__raw_writel(val, REG_TCSR0);
return 0;
}
static int nuc900_clockevent_set_periodic(struct clock_event_device *evt)
{
unsigned int val = __raw_readl(REG_TCSR0) & ~(0x03 << 27);
__raw_writel(timer0_load, REG_TICR0);
val |= (PERIOD | COUNTEN | INTEN | PRESCALE);
__raw_writel(val, REG_TCSR0);
return 0;
}
static int nuc900_clockevent_setnextevent(unsigned long evt,
struct clock_event_device *clk)
{
unsigned int val;
__raw_writel(evt, REG_TICR0);
val = __raw_readl(REG_TCSR0);
val |= (COUNTEN | INTEN | PRESCALE);
__raw_writel(val, REG_TCSR0);
return 0;
}
static struct clock_event_device nuc900_clockevent_device = {
.name = "nuc900-timer0",
.features = CLOCK_EVT_FEAT_PERIODIC |
CLOCK_EVT_FEAT_ONESHOT,
.set_state_shutdown = nuc900_clockevent_shutdown,
.set_state_periodic = nuc900_clockevent_set_periodic,
.set_state_oneshot = nuc900_clockevent_set_oneshot,
.tick_resume = nuc900_clockevent_shutdown,
.set_next_event = nuc900_clockevent_setnextevent,
.rating = 300,
};
/*IRQ handler for the timer*/
static irqreturn_t nuc900_timer0_interrupt(int irq, void *dev_id)
{
struct clock_event_device *evt = &nuc900_clockevent_device;
__raw_writel(0x01, REG_TISR); /* clear TIF0 */
evt->event_handler(evt);
return IRQ_HANDLED;
}
static struct irqaction nuc900_timer0_irq = {
.name = "nuc900-timer0",
.flags = IRQF_TIMER | IRQF_IRQPOLL,
.handler = nuc900_timer0_interrupt,
};
static void __init nuc900_clockevents_init(void)
{
unsigned int rate;
struct clk *clk = clk_get(NULL, "timer0");
BUG_ON(IS_ERR(clk));
__raw_writel(0x00, REG_TCSR0);
clk_enable(clk);
rate = clk_get_rate(clk) / (PRESCALE + 1);
timer0_load = (rate / TICKS_PER_SEC);
__raw_writel(RESETINT, REG_TISR);
setup_irq(IRQ_TIMER0, &nuc900_timer0_irq);
nuc900_clockevent_device.cpumask = cpumask_of(0);
clockevents_config_and_register(&nuc900_clockevent_device, rate,
0xf, 0xffffffff);
}
static void __init nuc900_clocksource_init(void)
{
unsigned int val;
unsigned int rate;
struct clk *clk = clk_get(NULL, "timer1");
BUG_ON(IS_ERR(clk));
__raw_writel(0x00, REG_TCSR1);
clk_enable(clk);
rate = clk_get_rate(clk) / (PRESCALE + 1);
__raw_writel(0xffffffff, REG_TICR1);
val = __raw_readl(REG_TCSR1);
val |= (COUNTEN | PERIOD | PRESCALE);
__raw_writel(val, REG_TCSR1);
clocksource_mmio_init(REG_TDR1, "nuc900-timer1", rate, 200,
TDR_SHIFT, clocksource_mmio_readl_down);
}
void __init nuc900_timer_init(void)
{
nuc900_clocksource_init();
nuc900_clockevents_init();
}
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