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-rw-r--r--arch/arm/mach-footbridge/dc21285-timer.c68
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/arm/mach-footbridge/dc21285-timer.c b/arch/arm/mach-footbridge/dc21285-timer.c
new file mode 100644
index 0000000000000..580e1d4bce081
--- /dev/null
+++ b/arch/arm/mach-footbridge/dc21285-timer.c
@@ -0,0 +1,68 @@
+/*
+ * linux/arch/arm/mach-footbridge/dc21285-timer.c
+ *
+ * Copyright (C) 1998 Russell King.
+ * Copyright (C) 1998 Phil Blundell
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+
+#include <asm/irq.h>
+
+#include <asm/hardware/dec21285.h>
+#include <asm/mach/time.h>
+
+#include "common.h"
+
+/*
+ * Footbridge timer 1 support.
+ */
+static unsigned long timer1_latch;
+
+static unsigned long timer1_gettimeoffset (void)
+{
+ unsigned long value = timer1_latch - *CSR_TIMER1_VALUE;
+
+ return ((tick_nsec / 1000) * value) / timer1_latch;
+}
+
+static irqreturn_t
+timer1_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+ write_seqlock(&xtime_lock);
+
+ *CSR_TIMER1_CLR = 0;
+
+ timer_tick(regs);
+
+ write_sequnlock(&xtime_lock);
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction footbridge_timer_irq = {
+ .name = "Timer1 timer tick",
+ .handler = timer1_interrupt,
+ .flags = SA_INTERRUPT,
+};
+
+/*
+ * Set up timer interrupt.
+ */
+static void __init footbridge_timer_init(void)
+{
+ isa_rtc_init();
+
+ timer1_latch = (mem_fclk_21285 + 8 * HZ) / (16 * HZ);
+
+ *CSR_TIMER1_CLR = 0;
+ *CSR_TIMER1_LOAD = timer1_latch;
+ *CSR_TIMER1_CNTL = TIMER_CNTL_ENABLE | TIMER_CNTL_AUTORELOAD | TIMER_CNTL_DIV16;
+
+ setup_irq(IRQ_TIMER1, &footbridge_timer_irq);
+}
+
+struct sys_timer footbridge_timer = {
+ .init = footbridge_timer_init,
+ .offset = timer1_gettimeoffset,
+};