1 files changed, 95 insertions, 0 deletions
diff --git a/arch/arm/mach-footbridge/isa-timer.c b/arch/arm/mach-footbridge/isa-timer.c
new file mode 100644
index 00000000..7020f1a3
--- /dev/null
+++ b/arch/arm/mach-footbridge/isa-timer.c
@@ -0,0 +1,95 @@
+/*
+ *  linux/arch/arm/mach-footbridge/isa-timer.c
+ *
+ *  Copyright (C) 1998 Russell King.
+ *  Copyright (C) 1998 Phil Blundell
+ */
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/timex.h>
+
+#include <asm/irq.h>
+#include <asm/i8253.h>
+#include <asm/mach/time.h>
+
+#include "common.h"
+
+DEFINE_RAW_SPINLOCK(i8253_lock);
+
+static void pit_set_mode(enum clock_event_mode mode,
+	struct clock_event_device *evt)
+{
+	unsigned long flags;
+
+	raw_local_irq_save(flags);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		outb_p(0x34, PIT_MODE);
+		outb_p(PIT_LATCH & 0xff, PIT_CH0);
+		outb_p(PIT_LATCH >> 8, PIT_CH0);
+		break;
+
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_UNUSED:
+		outb_p(0x30, PIT_MODE);
+		outb_p(0, PIT_CH0);
+		outb_p(0, PIT_CH0);
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+	case CLOCK_EVT_MODE_RESUME:
+		break;
+	}
+	local_irq_restore(flags);
+}
+
+static int pit_set_next_event(unsigned long delta,
+	struct clock_event_device *evt)
+{
+	return 0;
+}
+
+static struct clock_event_device pit_ce = {
+	.name		= "pit",
+	.features	= CLOCK_EVT_FEAT_PERIODIC,
+	.set_mode	= pit_set_mode,
+	.set_next_event	= pit_set_next_event,
+	.shift		= 32,
+};
+
+static irqreturn_t pit_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+	ce->event_handler(ce);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction pit_timer_irq = {
+	.name		= "pit",
+	.handler	= pit_timer_interrupt,
+	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+	.dev_id		= &pit_ce,
+};
+
+static void __init isa_timer_init(void)
+{
+	pit_ce.cpumask = cpumask_of(smp_processor_id());
+	pit_ce.mult = div_sc(PIT_TICK_RATE, NSEC_PER_SEC, pit_ce.shift);
+	pit_ce.max_delta_ns = clockevent_delta2ns(0x7fff, &pit_ce);
+	pit_ce.min_delta_ns = clockevent_delta2ns(0x000f, &pit_ce);
+
+	clocksource_i8253_init();
+
+	setup_irq(pit_ce.irq, &pit_timer_irq);
+	clockevents_register_device(&pit_ce);
+}
+
+struct sys_timer isa_timer = {
+	.init		= isa_timer_init,
+};