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-rw-r--r--kernel/arch/arm/plat-iop/time.c170
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diff --git a/kernel/arch/arm/plat-iop/time.c b/kernel/arch/arm/plat-iop/time.c
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+++ b/kernel/arch/arm/plat-iop/time.c
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+/*
+ * 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 <linux/io.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/export.h>
+#include <linux/sched_clock.h>
+#include <mach/hardware.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+#include <mach/time.h>
+
+/*
+ * Minimum clocksource/clockevent timer range in seconds
+ */
+#define IOP_MIN_RANGE 4
+
+/*
+ * IOP clocksource (free-running timer 1).
+ */
+static cycle_t notrace iop_clocksource_read(struct clocksource *unused)
+{
+ return 0xffffffffu - read_tcr1();
+}
+
+static struct clocksource iop_clocksource = {
+ .name = "iop_timer1",
+ .rating = 300,
+ .read = iop_clocksource_read,
+ .mask = CLOCKSOURCE_MASK(32),
+ .flags = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+/*
+ * IOP sched_clock() implementation via its clocksource.
+ */
+static u64 notrace iop_read_sched_clock(void)
+{
+ return 0xffffffffu - read_tcr1();
+}
+
+/*
+ * IOP clockevents (interrupting timer 0).
+ */
+static int iop_set_next_event(unsigned long delta,
+ struct clock_event_device *unused)
+{
+ u32 tmr = IOP_TMR_PRIVILEGED | IOP_TMR_RATIO_1_1;
+
+ BUG_ON(delta == 0);
+ write_tmr0(tmr & ~(IOP_TMR_EN | IOP_TMR_RELOAD));
+ write_tcr0(delta);
+ write_tmr0((tmr & ~IOP_TMR_RELOAD) | IOP_TMR_EN);
+
+ return 0;
+}
+
+static unsigned long ticks_per_jiffy;
+
+static void iop_set_mode(enum clock_event_mode mode,
+ struct clock_event_device *unused)
+{
+ u32 tmr = read_tmr0();
+
+ switch (mode) {
+ case CLOCK_EVT_MODE_PERIODIC:
+ write_tmr0(tmr & ~IOP_TMR_EN);
+ write_tcr0(ticks_per_jiffy - 1);
+ write_trr0(ticks_per_jiffy - 1);
+ tmr |= (IOP_TMR_RELOAD | IOP_TMR_EN);
+ break;
+ case CLOCK_EVT_MODE_ONESHOT:
+ /* ->set_next_event sets period and enables timer */
+ tmr &= ~(IOP_TMR_RELOAD | IOP_TMR_EN);
+ break;
+ case CLOCK_EVT_MODE_RESUME:
+ tmr |= IOP_TMR_EN;
+ break;
+ case CLOCK_EVT_MODE_SHUTDOWN:
+ case CLOCK_EVT_MODE_UNUSED:
+ default:
+ tmr &= ~IOP_TMR_EN;
+ break;
+ }
+
+ write_tmr0(tmr);
+}
+
+static struct clock_event_device iop_clockevent = {
+ .name = "iop_timer0",
+ .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+ .rating = 300,
+ .set_next_event = iop_set_next_event,
+ .set_mode = iop_set_mode,
+};
+
+static irqreturn_t
+iop_timer_interrupt(int irq, void *dev_id)
+{
+ struct clock_event_device *evt = dev_id;
+
+ write_tisr(1);
+ evt->event_handler(evt);
+ return IRQ_HANDLED;
+}
+
+static struct irqaction iop_timer_irq = {
+ .name = "IOP Timer Tick",
+ .handler = iop_timer_interrupt,
+ .flags = IRQF_TIMER | IRQF_IRQPOLL,
+ .dev_id = &iop_clockevent,
+};
+
+static unsigned long iop_tick_rate;
+unsigned long get_iop_tick_rate(void)
+{
+ return iop_tick_rate;
+}
+EXPORT_SYMBOL(get_iop_tick_rate);
+
+void __init iop_init_time(unsigned long tick_rate)
+{
+ u32 timer_ctl;
+
+ sched_clock_register(iop_read_sched_clock, 32, tick_rate);
+
+ ticks_per_jiffy = DIV_ROUND_CLOSEST(tick_rate, HZ);
+ iop_tick_rate = tick_rate;
+
+ timer_ctl = IOP_TMR_EN | IOP_TMR_PRIVILEGED |
+ IOP_TMR_RELOAD | IOP_TMR_RATIO_1_1;
+
+ /*
+ * Set up interrupting clockevent timer 0.
+ */
+ write_tmr0(timer_ctl & ~IOP_TMR_EN);
+ write_tisr(1);
+ setup_irq(IRQ_IOP_TIMER0, &iop_timer_irq);
+ iop_clockevent.cpumask = cpumask_of(0);
+ clockevents_config_and_register(&iop_clockevent, tick_rate,
+ 0xf, 0xfffffffe);
+
+ /*
+ * Set up free-running clocksource timer 1.
+ */
+ write_trr1(0xffffffff);
+ write_tcr1(0xffffffff);
+ write_tmr1(timer_ctl);
+ clocksource_register_hz(&iop_clocksource, tick_rate);
+}