1 files changed, 102 insertions, 0 deletions
diff --git a/arch/arm/mach-iop13xx/time.c b/arch/arm/mach-iop13xx/time.c
new file mode 100644
index 0000000..8b21365
--- /dev/null
+++ b/arch/arm/mach-iop13xx/time.c
@@ -0,0 +1,102 @@
+/*
+ * arch/arm/mach-iop13xx/time.c
+ *
+ * Timer code for IOP13xx (copied from IOP32x/IOP33x implementation)
+ *
+ * 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 <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+static unsigned long ticks_per_jiffy;
+static unsigned long ticks_per_usec;
+static unsigned long next_jiffy_time;
+
+static inline u32 read_tcr1(void)
+{
+	u32 val;
+	asm volatile("mrc p6, 0, %0, c3, c9, 0" : "=r" (val));
+	return val;
+}
+
+unsigned long iop13xx_gettimeoffset(void)
+{
+	unsigned long offset;
+	u32 cp_flags;
+
+	cp_flags = iop13xx_cp6_save();
+	offset = next_jiffy_time - read_tcr1();
+	iop13xx_cp6_restore(cp_flags);
+
+	return offset / ticks_per_usec;
+}
+
+static irqreturn_t
+iop13xx_timer_interrupt(int irq, void *dev_id)
+{
+	u32 cp_flags = iop13xx_cp6_save();
+
+	write_seqlock(&xtime_lock);
+
+	asm volatile("mcr p6, 0, %0, c6, c9, 0" : : "r" (1));
+
+	while ((signed long)(next_jiffy_time - read_tcr1())
+							>= ticks_per_jiffy) {
+		timer_tick();
+		next_jiffy_time -= ticks_per_jiffy;
+	}
+
+	write_sequnlock(&xtime_lock);
+
+	iop13xx_cp6_restore(cp_flags);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction iop13xx_timer_irq = {
+	.name		= "IOP13XX Timer Tick",
+	.handler	= iop13xx_timer_interrupt,
+	.flags		= IRQF_DISABLED | IRQF_TIMER,
+};
+
+void __init iop13xx_init_time(unsigned long tick_rate)
+{
+	u32 timer_ctl;
+	u32 cp_flags;
+
+	ticks_per_jiffy = (tick_rate + HZ/2) / HZ;
+	ticks_per_usec = tick_rate / 1000000;
+	next_jiffy_time = 0xffffffff;
+
+	timer_ctl = IOP13XX_TMR_EN | IOP13XX_TMR_PRIVILEGED |
+			IOP13XX_TMR_RELOAD | IOP13XX_TMR_RATIO_1_1;
+
+	/*
+	 * We use timer 0 for our timer interrupt, and timer 1 as
+	 * monotonic counter for tracking missed jiffies.
+	 */
+	cp_flags = iop13xx_cp6_save();
+	asm volatile("mcr p6, 0, %0, c4, c9, 0" : : "r" (ticks_per_jiffy - 1));
+	asm volatile("mcr p6, 0, %0, c0, c9, 0" : : "r" (timer_ctl));
+	asm volatile("mcr p6, 0, %0, c5, c9, 0" : : "r" (0xffffffff));
+	asm volatile("mcr p6, 0, %0, c1, c9, 0" : : "r" (timer_ctl));
+	iop13xx_cp6_restore(cp_flags);
+
+	setup_irq(IRQ_IOP13XX_TIMER0, &iop13xx_timer_irq);
+}