Initial file dump from open source releaseHEADmaster

1 files changed, 135 insertions, 0 deletions

diff --git a/arch/arm/mach-sa1100/time.c b/arch/arm/mach-sa1100/time.c
new file mode 100644
index 00000000..a59a13a6
--- /dev/null
+++ b/arch/arm/mach-sa1100/time.c
@@ -0,0 +1,135 @@
+/*
+ * linux/arch/arm/mach-sa1100/time.c
+ *
+ * Copyright (C) 1998 Deborah Wallach.
+ * Twiddles  (C) 1999 Hugo Fiennes <hugo@empeg.com>
+ *
+ * 2000/03/29 (C) Nicolas Pitre <nico@fluxnic.net>
+ *	Rewritten: big cleanup, much simpler, better HZ accuracy.
+ *
+ */
+#include <linux/init.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/timex.h>
+#include <linux/clockchips.h>
+
+#include <asm/mach/time.h>
+#include <asm/sched_clock.h>
+#include <mach/hardware.h>
+#include <mach/irqs.h>
+
+static u32 notrace sa1100_read_sched_clock(void)
+{
+	return readl_relaxed(OSCR);
+}
+
+#define MIN_OSCR_DELTA 2
+
+static irqreturn_t sa1100_ost0_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *c = dev_id;
+
+	/* Disarm the compare/match, signal the event. */
+	writel_relaxed(readl_relaxed(OIER) & ~OIER_E0, OIER);
+	writel_relaxed(OSSR_M0, OSSR);
+	c->event_handler(c);
+
+	return IRQ_HANDLED;
+}
+
+static int
+sa1100_osmr0_set_next_event(unsigned long delta, struct clock_event_device *c)
+{
+	unsigned long next, oscr;
+
+	writel_relaxed(readl_relaxed(OIER) | OIER_E0, OIER);
+	next = readl_relaxed(OSCR) + delta;
+	writel_relaxed(next, OSMR0);
+	oscr = readl_relaxed(OSCR);
+
+	return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
+}
+
+static void
+sa1100_osmr0_set_mode(enum clock_event_mode mode, struct clock_event_device *c)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_ONESHOT:
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		writel_relaxed(readl_relaxed(OIER) & ~OIER_E0, OIER);
+		writel_relaxed(OSSR_M0, OSSR);
+		break;
+
+	case CLOCK_EVT_MODE_RESUME:
+	case CLOCK_EVT_MODE_PERIODIC:
+		break;
+	}
+}
+
+#ifdef CONFIG_PM
+unsigned long osmr[4], oier;
+
+static void sa1100_timer_suspend(struct clock_event_device *cedev)
+{
+	osmr[0] = readl_relaxed(OSMR0);
+	osmr[1] = readl_relaxed(OSMR1);
+	osmr[2] = readl_relaxed(OSMR2);
+	osmr[3] = readl_relaxed(OSMR3);
+	oier = readl_relaxed(OIER);
+}
+
+static void sa1100_timer_resume(struct clock_event_device *cedev)
+{
+	writel_relaxed(0x0f, OSSR);
+	writel_relaxed(osmr[0], OSMR0);
+	writel_relaxed(osmr[1], OSMR1);
+	writel_relaxed(osmr[2], OSMR2);
+	writel_relaxed(osmr[3], OSMR3);
+	writel_relaxed(oier, OIER);
+
+	/*
+	 * OSMR0 is the system timer: make sure OSCR is sufficiently behind
+	 */
+	writel_relaxed(OSMR0 - LATCH, OSCR);
+}
+#else
+#define sa1100_timer_suspend NULL
+#define sa1100_timer_resume NULL
+#endif
+
+static struct clock_event_device ckevt_sa1100_osmr0 = {
+	.name		= "osmr0",
+	.features	= CLOCK_EVT_FEAT_ONESHOT,
+	.rating		= 200,
+	.set_next_event	= sa1100_osmr0_set_next_event,
+	.set_mode	= sa1100_osmr0_set_mode,
+	.suspend	= sa1100_timer_suspend,
+	.resume		= sa1100_timer_resume,
+};
+
+static struct irqaction sa1100_timer_irq = {
+	.name		= "ost0",
+	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= sa1100_ost0_interrupt,
+	.dev_id		= &ckevt_sa1100_osmr0,
+};
+
+void __init sa1100_timer_init(void)
+{
+	writel_relaxed(0, OIER);
+	writel_relaxed(OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3, OSSR);
+
+	setup_sched_clock(sa1100_read_sched_clock, 32, 3686400);
+
+	ckevt_sa1100_osmr0.cpumask = cpumask_of(0);
+
+	setup_irq(IRQ_OST0, &sa1100_timer_irq);
+
+	clocksource_mmio_init(OSCR, "oscr", CLOCK_TICK_RATE, 200, 32,
+		clocksource_mmio_readl_up);
+	clockevents_config_and_register(&ckevt_sa1100_osmr0, 3686400,
+					MIN_OSCR_DELTA * 2, 0x7fffffff);
+}