1 files changed, 106 insertions, 0 deletions
diff --git a/arch/arm/mach-iop33x/time.c b/arch/arm/mach-iop33x/time.c
new file mode 100644
index 00000000000..d839cd0d926
--- /dev/null
+++ b/arch/arm/mach-iop33x/time.c
@@ -0,0 +1,106 @@
+/*
+ * arch/arm/mach-iop33x/time.c
+ *
+ * Timer code for IOP331 based systems
+ *
+ * Author: Dave Jiang <dave.jiang@intel.com>
+ *
+ * Copyright 2003 Intel Corp.
+ *
+ *  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 <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+static inline unsigned long get_elapsed(void)
+{
+	return LATCH - *IOP331_TU_TCR0;
+}
+
+static unsigned long iop331_gettimeoffset(void)
+{
+	unsigned long elapsed, usec;
+	u32 tisr1, tisr2;
+
+	/*
+	 * If an interrupt was pending before we read the timer,
+	 * we've already wrapped.  Factor this into the time.
+	 * If an interrupt was pending after we read the timer,
+	 * it may have wrapped between checking the interrupt
+	 * status and reading the timer.  Re-read the timer to
+	 * be sure its value is after the wrap.
+	 */
+
+	asm volatile("mrc p6, 0, %0, c6, c1, 0" : "=r" (tisr1));
+	elapsed = get_elapsed();
+	asm volatile("mrc p6, 0, %0, c6, c1, 0" : "=r" (tisr2));
+
+	if(tisr1 & 1)
+		elapsed += LATCH;
+	else if (tisr2 & 1)
+		elapsed = LATCH + get_elapsed();
+
+	/*
+	 * Now convert them to usec.
+	 */
+	usec = (unsigned long)(elapsed / (CLOCK_TICK_RATE/1000000));
+
+	return usec;
+}
+
+static irqreturn_t
+iop331_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	u32 tisr;
+
+	write_seqlock(&xtime_lock);
+
+	asm volatile("mrc p6, 0, %0, c6, c1, 0" : "=r" (tisr));
+	tisr |= 1;
+	asm volatile("mcr p6, 0, %0, c6, c1, 0" : : "r" (tisr));
+
+	timer_tick(regs);
+
+	write_sequnlock(&xtime_lock);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction iop331_timer_irq = {
+	.name		= "IOP331 Timer Tick",
+	.handler	= iop331_timer_interrupt,
+	.flags		= IRQF_DISABLED | IRQF_TIMER,
+};
+
+static void __init iop331_timer_init(void)
+{
+	u32 timer_ctl;
+
+	setup_irq(IRQ_IOP331_TIMER0, &iop331_timer_irq);
+
+	timer_ctl = IOP331_TMR_EN | IOP331_TMR_PRIVILEGED | IOP331_TMR_RELOAD |
+			IOP331_TMR_RATIO_1_1;
+
+	asm volatile("mcr p6, 0, %0, c4, c1, 0" : : "r" (LATCH));
+
+	asm volatile("mcr p6, 0, %0, c0, c1, 0"	: : "r" (timer_ctl));
+
+}
+
+struct sys_timer iop331_timer = {
+	.init		= iop331_timer_init,
+	.offset		= iop331_gettimeoffset,
+};