1 files changed, 109 insertions, 0 deletions

diff --git a/arch/arm/mach-iop3xx/iop321-time.c b/arch/arm/mach-iop3xx/iop321-time.c
new file mode 100644
index 000000000000..9b7dd64d1b8f
--- /dev/null
+++ b/arch/arm/mach-iop3xx/iop321-time.c
@@ -0,0 +1,109 @@
+/*
+ * arch/arm/mach-iop3xx/iop321-time.c
+ *
+ * Timer code for IOP321 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 <asm/hardware.h>
+#include <asm/io.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/mach-types.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#define IOP321_TIME_SYNC 0
+
+static inline unsigned long get_elapsed(void)
+{
+        return LATCH - *IOP321_TU_TCR0;
+}
+
+static unsigned long iop321_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 * (tick_nsec / 1000)) / LATCH;
+
+        return usec;
+}
+
+static irqreturn_t
+iop321_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 iop321_timer_irq = {
+        .name           = "IOP321 Timer Tick",
+        .handler        = iop321_timer_interrupt,
+        .flags          = SA_INTERRUPT
+};
+
+static void __init iop321_timer_init(void)
+{
+        u32 timer_ctl;
+
+        setup_irq(IRQ_IOP321_TIMER0, &iop321_timer_irq);
+
+        timer_ctl = IOP321_TMR_EN | IOP321_TMR_PRIVILEGED | IOP321_TMR_RELOAD |
+                        IOP321_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 iop321_timer = {
+        .init           = &iop321_timer_init,
+        .offset         = iop321_gettimeoffset,
+};