1 files changed, 247 insertions, 0 deletions
diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
new file mode 100644
index 00000000..81280825
--- /dev/null
+++ b/arch/arm/mach-msm/timer.c
@@ -0,0 +1,247 @@
+/*
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+
+#include <asm/mach/time.h>
+#include <asm/hardware/gic.h>
+#include <asm/localtimer.h>
+#include <asm/sched_clock.h>
+
+#include <mach/msm_iomap.h>
+#include <mach/cpu.h>
+#include <mach/board.h>
+
+#define TIMER_MATCH_VAL         0x0000
+#define TIMER_COUNT_VAL         0x0004
+#define TIMER_ENABLE            0x0008
+#define TIMER_ENABLE_CLR_ON_MATCH_EN    BIT(1)
+#define TIMER_ENABLE_EN                 BIT(0)
+#define TIMER_CLEAR             0x000C
+#define DGT_CLK_CTL             0x0034
+#define DGT_CLK_CTL_DIV_4	0x3
+
+#define GPT_HZ 32768
+
+#define MSM_DGT_SHIFT 5
+
+static void __iomem *event_base;
+
+static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+	/* Stop the timer tick */
+	if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
+		u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+		ctrl &= ~TIMER_ENABLE_EN;
+		writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+	}
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static int msm_timer_set_next_event(unsigned long cycles,
+				    struct clock_event_device *evt)
+{
+	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+
+	writel_relaxed(0, event_base + TIMER_CLEAR);
+	writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
+	writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
+	return 0;
+}
+
+static void msm_timer_set_mode(enum clock_event_mode mode,
+			      struct clock_event_device *evt)
+{
+	u32 ctrl;
+
+	ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+	ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
+
+	switch (mode) {
+	case CLOCK_EVT_MODE_RESUME:
+	case CLOCK_EVT_MODE_PERIODIC:
+		break;
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* Timer is enabled in set_next_event */
+		break;
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		break;
+	}
+	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+}
+
+static struct clock_event_device msm_clockevent = {
+	.name		= "gp_timer",
+	.features	= CLOCK_EVT_FEAT_ONESHOT,
+	.rating		= 200,
+	.set_next_event	= msm_timer_set_next_event,
+	.set_mode	= msm_timer_set_mode,
+};
+
+static union {
+	struct clock_event_device *evt;
+	struct clock_event_device __percpu **percpu_evt;
+} msm_evt;
+
+static void __iomem *source_base;
+
+static notrace cycle_t msm_read_timer_count(struct clocksource *cs)
+{
+	return readl_relaxed(source_base + TIMER_COUNT_VAL);
+}
+
+static notrace cycle_t msm_read_timer_count_shift(struct clocksource *cs)
+{
+	/*
+	 * Shift timer count down by a constant due to unreliable lower bits
+	 * on some targets.
+	 */
+	return msm_read_timer_count(cs) >> MSM_DGT_SHIFT;
+}
+
+static struct clocksource msm_clocksource = {
+	.name	= "dg_timer",
+	.rating	= 300,
+	.read	= msm_read_timer_count,
+	.mask	= CLOCKSOURCE_MASK(32),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+#ifdef CONFIG_LOCAL_TIMERS
+static int __cpuinit msm_local_timer_setup(struct clock_event_device *evt)
+{
+	/* Use existing clock_event for cpu 0 */
+	if (!smp_processor_id())
+		return 0;
+
+	writel_relaxed(0, event_base + TIMER_ENABLE);
+	writel_relaxed(0, event_base + TIMER_CLEAR);
+	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
+	evt->irq = msm_clockevent.irq;
+	evt->name = "local_timer";
+	evt->features = msm_clockevent.features;
+	evt->rating = msm_clockevent.rating;
+	evt->set_mode = msm_timer_set_mode;
+	evt->set_next_event = msm_timer_set_next_event;
+	evt->shift = msm_clockevent.shift;
+	evt->mult = div_sc(GPT_HZ, NSEC_PER_SEC, evt->shift);
+	evt->max_delta_ns = clockevent_delta2ns(0xf0000000, evt);
+	evt->min_delta_ns = clockevent_delta2ns(4, evt);
+
+	*__this_cpu_ptr(msm_evt.percpu_evt) = evt;
+	clockevents_register_device(evt);
+	enable_percpu_irq(evt->irq, 0);
+	return 0;
+}
+
+static void msm_local_timer_stop(struct clock_event_device *evt)
+{
+	evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
+	disable_percpu_irq(evt->irq);
+}
+
+static struct local_timer_ops msm_local_timer_ops __cpuinitdata = {
+	.setup	= msm_local_timer_setup,
+	.stop	= msm_local_timer_stop,
+};
+#endif /* CONFIG_LOCAL_TIMERS */
+
+static notrace u32 msm_sched_clock_read(void)
+{
+	return msm_clocksource.read(&msm_clocksource);
+}
+
+static void __init msm_timer_init(void)
+{
+	struct clock_event_device *ce = &msm_clockevent;
+	struct clocksource *cs = &msm_clocksource;
+	int res;
+	u32 dgt_hz;
+
+	if (cpu_is_msm7x01()) {
+		event_base = MSM_CSR_BASE;
+		source_base = MSM_CSR_BASE + 0x10;
+		dgt_hz = 19200000 >> MSM_DGT_SHIFT; /* 600 KHz */
+		cs->read = msm_read_timer_count_shift;
+		cs->mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT));
+	} else if (cpu_is_msm7x30()) {
+		event_base = MSM_CSR_BASE + 0x04;
+		source_base = MSM_CSR_BASE + 0x24;
+		dgt_hz = 24576000 / 4;
+	} else if (cpu_is_qsd8x50()) {
+		event_base = MSM_CSR_BASE;
+		source_base = MSM_CSR_BASE + 0x10;
+		dgt_hz = 19200000 / 4;
+	} else if (cpu_is_msm8x60() || cpu_is_msm8960()) {
+		event_base = MSM_TMR_BASE + 0x04;
+		/* Use CPU0's timer as the global clock source. */
+		source_base = MSM_TMR0_BASE + 0x24;
+		dgt_hz = 27000000 / 4;
+		writel_relaxed(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
+	} else
+		BUG();
+
+	writel_relaxed(0, event_base + TIMER_ENABLE);
+	writel_relaxed(0, event_base + TIMER_CLEAR);
+	writel_relaxed(~0, event_base + TIMER_MATCH_VAL);
+	ce->cpumask = cpumask_of(0);
+
+	ce->irq = INT_GP_TIMER_EXP;
+	clockevents_config_and_register(ce, GPT_HZ, 4, 0xffffffff);
+	if (cpu_is_msm8x60() || cpu_is_msm8960()) {
+		msm_evt.percpu_evt = alloc_percpu(struct clock_event_device *);
+		if (!msm_evt.percpu_evt) {
+			pr_err("memory allocation failed for %s\n", ce->name);
+			goto err;
+		}
+		*__this_cpu_ptr(msm_evt.percpu_evt) = ce;
+		res = request_percpu_irq(ce->irq, msm_timer_interrupt,
+					 ce->name, msm_evt.percpu_evt);
+		if (!res) {
+			enable_percpu_irq(ce->irq, 0);
+#ifdef CONFIG_LOCAL_TIMERS
+			local_timer_register(&msm_local_timer_ops);
+#endif
+		}
+	} else {
+		msm_evt.evt = ce;
+		res = request_irq(ce->irq, msm_timer_interrupt,
+				  IRQF_TIMER | IRQF_NOBALANCING |
+				  IRQF_TRIGGER_RISING, ce->name, &msm_evt.evt);
+	}
+
+	if (res)
+		pr_err("request_irq failed for %s\n", ce->name);
+err:
+	writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
+	res = clocksource_register_hz(cs, dgt_hz);
+	if (res)
+		pr_err("clocksource_register failed\n");
+	setup_sched_clock(msm_sched_clock_read,
+			cpu_is_msm7x01() ? 32 - MSM_DGT_SHIFT : 32, dgt_hz);
+}
+
+struct sys_timer msm_timer = {
+	.init = msm_timer_init
+};