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-rw-r--r--arch/arm/mach-gemini/time.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/arch/arm/mach-gemini/time.c b/arch/arm/mach-gemini/time.c
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+++ b/arch/arm/mach-gemini/time.c
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+/*
+ * Copyright (C) 2001-2006 Storlink, Corp.
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ *
+ * 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/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <mach/hardware.h>
+#include <mach/global_reg.h>
+#include <asm/mach/time.h>
+
+/*
+ * Register definitions for the timers
+ */
+#define TIMER_COUNT(BASE_ADDR) (BASE_ADDR + 0x00)
+#define TIMER_LOAD(BASE_ADDR) (BASE_ADDR + 0x04)
+#define TIMER_MATCH1(BASE_ADDR) (BASE_ADDR + 0x08)
+#define TIMER_MATCH2(BASE_ADDR) (BASE_ADDR + 0x0C)
+#define TIMER_CR(BASE_ADDR) (BASE_ADDR + 0x30)
+
+#define TIMER_1_CR_ENABLE (1 << 0)
+#define TIMER_1_CR_CLOCK (1 << 1)
+#define TIMER_1_CR_INT (1 << 2)
+#define TIMER_2_CR_ENABLE (1 << 3)
+#define TIMER_2_CR_CLOCK (1 << 4)
+#define TIMER_2_CR_INT (1 << 5)
+#define TIMER_3_CR_ENABLE (1 << 6)
+#define TIMER_3_CR_CLOCK (1 << 7)
+#define TIMER_3_CR_INT (1 << 8)
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t gemini_timer_interrupt(int irq, void *dev_id)
+{
+ timer_tick();
+
+ return IRQ_HANDLED;
+}
+
+static struct irqaction gemini_timer_irq = {
+ .name = "Gemini Timer Tick",
+ .flags = IRQF_DISABLED | IRQF_TIMER,
+ .handler = gemini_timer_interrupt,
+};
+
+/*
+ * Set up timer interrupt, and return the current time in seconds.
+ */
+void __init gemini_timer_init(void)
+{
+ unsigned int tick_rate, reg_v;
+
+ reg_v = __raw_readl(IO_ADDRESS(GEMINI_GLOBAL_BASE + GLOBAL_STATUS));
+ tick_rate = REG_TO_AHB_SPEED(reg_v) * 1000000;
+
+ printk(KERN_INFO "Bus: %dMHz", tick_rate / 1000000);
+
+ tick_rate /= 6; /* APB bus run AHB*(1/6) */
+
+ switch(reg_v & CPU_AHB_RATIO_MASK) {
+ case CPU_AHB_1_1:
+ printk(KERN_CONT "(1/1)\n");
+ break;
+ case CPU_AHB_3_2:
+ printk(KERN_CONT "(3/2)\n");
+ break;
+ case CPU_AHB_24_13:
+ printk(KERN_CONT "(24/13)\n");
+ break;
+ case CPU_AHB_2_1:
+ printk(KERN_CONT "(2/1)\n");
+ break;
+ }
+
+ /*
+ * Make irqs happen for the system timer
+ */
+ setup_irq(IRQ_TIMER2, &gemini_timer_irq);
+ /* Start the timer */
+ __raw_writel(tick_rate / HZ, TIMER_COUNT(IO_ADDRESS(GEMINI_TIMER2_BASE)));
+ __raw_writel(tick_rate / HZ, TIMER_LOAD(IO_ADDRESS(GEMINI_TIMER2_BASE)));
+ __raw_writel(TIMER_2_CR_ENABLE | TIMER_2_CR_INT, TIMER_CR(IO_ADDRESS(GEMINI_TIMER_BASE)));
+}
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