From 849369d6c66d3054688672f97d31fceb8e8230fb Mon Sep 17 00:00:00 2001
From: root <root@artemis.panaceas.org>
Date: Fri, 25 Dec 2015 04:40:36 +0000
Subject: initial_commit

---
 arch/arm/mach-w90x900/time.c | 176 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 176 insertions(+)
 create mode 100644 arch/arm/mach-w90x900/time.c

(limited to 'arch/arm/mach-w90x900/time.c')

diff --git a/arch/arm/mach-w90x900/time.c b/arch/arm/mach-w90x900/time.c
new file mode 100644
index 00000000..a2c4e2d0
--- /dev/null
+++ b/arch/arm/mach-w90x900/time.c
@@ -0,0 +1,176 @@
+/*
+ * linux/arch/arm/mach-w90x900/time.c
+ *
+ * Based on linux/arch/arm/plat-s3c24xx/time.c by Ben Dooks
+ *
+ * Copyright (c) 2009 Nuvoton technology corporation
+ * All rights reserved.
+ *
+ * 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 <linux/clocksource.h>
+#include <linux/clockchips.h>
+
+#include <asm/mach-types.h>
+#include <asm/mach/irq.h>
+#include <asm/mach/time.h>
+
+#include <mach/map.h>
+#include <mach/regs-timer.h>
+
+#define RESETINT	0x1f
+#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 */
+
+#define	TDR_SHIFT	24
+
+static unsigned int timer0_load;
+
+static void nuc900_clockevent_setmode(enum clock_event_mode mode,
+		struct clock_event_device *clk)
+{
+	unsigned int val;
+
+	val = __raw_readl(REG_TCSR0);
+	val &= ~(0x03 << 27);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		__raw_writel(timer0_load, REG_TICR0);
+		val |= (PERIOD | COUNTEN | INTEN | PRESCALE);
+		break;
+
+	case CLOCK_EVT_MODE_ONESHOT:
+		val |= (ONESHOT | COUNTEN | INTEN | PRESCALE);
+		break;
+
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	case CLOCK_EVT_MODE_RESUME:
+		break;
+	}
+
+	__raw_writel(val, REG_TCSR0);
+}
+
+static int nuc900_clockevent_setnextevent(unsigned long evt,
+		struct clock_event_device *clk)
+{
+	unsigned int val;
+
+	__raw_writel(evt, REG_TICR0);
+
+	val = __raw_readl(REG_TCSR0);
+	val |= (COUNTEN | INTEN | PRESCALE);
+	__raw_writel(val, REG_TCSR0);
+
+	return 0;
+}
+
+static struct clock_event_device nuc900_clockevent_device = {
+	.name		= "nuc900-timer0",
+	.shift		= 32,
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode	= nuc900_clockevent_setmode,
+	.set_next_event	= nuc900_clockevent_setnextevent,
+	.rating		= 300,
+};
+
+/*IRQ handler for the timer*/
+
+static irqreturn_t nuc900_timer0_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = &nuc900_clockevent_device;
+
+	__raw_writel(0x01, REG_TISR); /* clear TIF0 */
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction nuc900_timer0_irq = {
+	.name		= "nuc900-timer0",
+	.flags		= IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= nuc900_timer0_interrupt,
+};
+
+static void __init nuc900_clockevents_init(void)
+{
+	unsigned int rate;
+	struct clk *clk = clk_get(NULL, "timer0");
+
+	BUG_ON(IS_ERR(clk));
+
+	__raw_writel(0x00, REG_TCSR0);
+
+	clk_enable(clk);
+	rate = clk_get_rate(clk) / (PRESCALE + 1);
+
+	timer0_load = (rate / TICKS_PER_SEC);
+
+	__raw_writel(RESETINT, REG_TISR);
+	setup_irq(IRQ_TIMER0, &nuc900_timer0_irq);
+
+	nuc900_clockevent_device.mult = div_sc(rate, NSEC_PER_SEC,
+					nuc900_clockevent_device.shift);
+	nuc900_clockevent_device.max_delta_ns = clockevent_delta2ns(0xffffffff,
+					&nuc900_clockevent_device);
+	nuc900_clockevent_device.min_delta_ns = clockevent_delta2ns(0xf,
+					&nuc900_clockevent_device);
+	nuc900_clockevent_device.cpumask = cpumask_of(0);
+
+	clockevents_register_device(&nuc900_clockevent_device);
+}
+
+static void __init nuc900_clocksource_init(void)
+{
+	unsigned int val;
+	unsigned int rate;
+	struct clk *clk = clk_get(NULL, "timer1");
+
+	BUG_ON(IS_ERR(clk));
+
+	__raw_writel(0x00, REG_TCSR1);
+
+	clk_enable(clk);
+	rate = clk_get_rate(clk) / (PRESCALE + 1);
+
+	__raw_writel(0xffffffff, REG_TICR1);
+
+	val = __raw_readl(REG_TCSR1);
+	val |= (COUNTEN | PERIOD | PRESCALE);
+	__raw_writel(val, REG_TCSR1);
+
+	clocksource_mmio_init(REG_TDR1, "nuc900-timer1", rate, 200,
+		TDR_SHIFT, clocksource_mmio_readl_down);
+}
+
+static void __init nuc900_timer_init(void)
+{
+	nuc900_clocksource_init();
+	nuc900_clockevents_init();
+}
+
+struct sys_timer nuc900_timer = {
+	.init		= nuc900_timer_init,
+};
-- 
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