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Diffstat (limited to 'arch/arm/mach-nuc93x/time.c')
-rw-r--r--arch/arm/mach-nuc93x/time.c100
1 files changed, 100 insertions, 0 deletions
diff --git a/arch/arm/mach-nuc93x/time.c b/arch/arm/mach-nuc93x/time.c
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+++ b/arch/arm/mach-nuc93x/time.c
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+/*
+ * linux/arch/arm/mach-nuc93x/time.c
+ *
+ * Copyright (c) 2009 Nuvoton technology corporation.
+ *
+ * Wan ZongShun <mcuos.com@gmail.com>
+ *
+ * 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/sched.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/leds.h>
+
+#include <asm/mach-types.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#include <mach/system.h>
+#include <mach/map.h>
+#include <mach/regs-timer.h>
+
+#define RESETINT 0x01
+#define PERIOD (0x01 << 27)
+#define ONESHOT (0x00 << 27)
+#define COUNTEN (0x01 << 30)
+#define INTEN (0x01 << 29)
+
+#define TICKS_PER_SEC 100
+#define PRESCALE 0x63 /* Divider = prescale + 1 */
+
+unsigned int timer0_load;
+
+static unsigned long nuc93x_gettimeoffset(void)
+{
+ return 0;
+}
+
+/*IRQ handler for the timer*/
+
+static irqreturn_t nuc93x_timer_interrupt(int irq, void *dev_id)
+{
+ timer_tick();
+ __raw_writel(0x01, REG_TISR); /* clear TIF0 */
+ return IRQ_HANDLED;
+}
+
+static struct irqaction nuc93x_timer_irq = {
+ .name = "nuc93x Timer Tick",
+ .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+ .handler = nuc93x_timer_interrupt,
+};
+
+/*Set up timer reg.*/
+
+static void nuc93x_timer_setup(void)
+{
+ struct clk *ck_ext = clk_get(NULL, "ext");
+ struct clk *ck_timer = clk_get(NULL, "timer");
+ unsigned int rate, val = 0;
+
+ BUG_ON(IS_ERR(ck_ext) || IS_ERR(ck_timer));
+
+ clk_enable(ck_timer);
+ rate = clk_get_rate(ck_ext);
+ clk_put(ck_ext);
+ rate = rate / (PRESCALE + 0x01);
+
+ /* set a known state */
+ __raw_writel(0x00, REG_TCSR0);
+ __raw_writel(RESETINT, REG_TISR);
+
+ timer0_load = (rate / TICKS_PER_SEC);
+ __raw_writel(timer0_load, REG_TICR0);
+
+ val |= (PERIOD | COUNTEN | INTEN | PRESCALE);;
+ __raw_writel(val, REG_TCSR0);
+
+}
+
+static void __init nuc93x_timer_init(void)
+{
+ nuc93x_timer_setup();
+ setup_irq(IRQ_TIMER0, &nuc93x_timer_irq);
+}
+
+struct sys_timer nuc93x_timer = {
+ .init = nuc93x_timer_init,
+ .offset = nuc93x_gettimeoffset,
+ .resume = nuc93x_timer_setup
+};