ARM: sirf: use clocksource_of infrastructure

This moves the two sirf clocksource drivers to drivers/clocksource
and integrates them into the framework for locating the clock sources
automatically.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Barry Song <Baohua.Song@csr.com>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>

3 files changed, 516 insertions, 0 deletions

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 4d8283aec5b5..5e2176f9453f 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -16,6 +16,8 @@ obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
 obj-$(CONFIG_CLKSRC_DBX500_PRCMU)	+= clksrc-dbx500-prcmu.o
 obj-$(CONFIG_ARMADA_370_XP_TIMER)	+= time-armada-370-xp.o
 obj-$(CONFIG_ARCH_BCM2835)	+= bcm2835_timer.o
+obj-$(CONFIG_ARCH_MARCO)	+= timer-marco.o
+obj-$(CONFIG_ARCH_PRIMA2)	+= timer-prima2.o
 obj-$(CONFIG_SUNXI_TIMER)	+= sunxi_timer.o
 obj-$(CONFIG_ARCH_TEGRA)	+= tegra20_timer.o
 obj-$(CONFIG_VT8500_TIMER)	+= vt8500_timer.o
diff --git a/drivers/clocksource/timer-marco.c b/drivers/clocksource/timer-marco.c
new file mode 100644
index 000000000000..97738dbf3e3b
--- /dev/null
+++ b/drivers/clocksource/timer-marco.c
@@ -0,0 +1,299 @@
+/*
+ * System timer for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <asm/sched_clock.h>
+#include <asm/localtimer.h>
+#include <asm/mach/time.h>
+
+#define SIRFSOC_TIMER_32COUNTER_0_CTRL			0x0000
+#define SIRFSOC_TIMER_32COUNTER_1_CTRL			0x0004
+#define SIRFSOC_TIMER_MATCH_0				0x0018
+#define SIRFSOC_TIMER_MATCH_1				0x001c
+#define SIRFSOC_TIMER_COUNTER_0				0x0048
+#define SIRFSOC_TIMER_COUNTER_1				0x004c
+#define SIRFSOC_TIMER_INTR_STATUS			0x0060
+#define SIRFSOC_TIMER_WATCHDOG_EN			0x0064
+#define SIRFSOC_TIMER_64COUNTER_CTRL			0x0068
+#define SIRFSOC_TIMER_64COUNTER_LO			0x006c
+#define SIRFSOC_TIMER_64COUNTER_HI			0x0070
+#define SIRFSOC_TIMER_64COUNTER_LOAD_LO			0x0074
+#define SIRFSOC_TIMER_64COUNTER_LOAD_HI			0x0078
+#define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO		0x007c
+#define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI		0x0080
+
+#define SIRFSOC_TIMER_REG_CNT 6
+
+static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
+	SIRFSOC_TIMER_WATCHDOG_EN,
+	SIRFSOC_TIMER_32COUNTER_0_CTRL,
+	SIRFSOC_TIMER_32COUNTER_1_CTRL,
+	SIRFSOC_TIMER_64COUNTER_CTRL,
+	SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,
+	SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,
+};
+
+static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
+
+static void __iomem *sirfsoc_timer_base;
+
+/* disable count and interrupt */
+static inline void sirfsoc_timer_count_disable(int idx)
+{
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,
+		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
+}
+
+/* enable count and interrupt */
+static inline void sirfsoc_timer_count_enable(int idx)
+{
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) | 0x7,
+		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
+}
+
+/* timer interrupt handler */
+static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+	int cpu = smp_processor_id();
+
+	/* clear timer interrupt */
+	writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
+
+	if (ce->mode == CLOCK_EVT_MODE_ONESHOT)
+		sirfsoc_timer_count_disable(cpu);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+/* read 64-bit timer counter */
+static cycle_t sirfsoc_timer_read(struct clocksource *cs)
+{
+	u64 cycles;
+
+	writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+			BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+
+	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);
+	cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO);
+
+	return cycles;
+}
+
+static int sirfsoc_timer_set_next_event(unsigned long delta,
+	struct clock_event_device *ce)
+{
+	int cpu = smp_processor_id();
+
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +
+		4 * cpu);
+	writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +
+		4 * cpu);
+
+	/* enable the tick */
+	sirfsoc_timer_count_enable(cpu);
+
+	return 0;
+}
+
+static void sirfsoc_timer_set_mode(enum clock_event_mode mode,
+	struct clock_event_device *ce)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_ONESHOT:
+		/* enable in set_next_event */
+		break;
+	default:
+		break;
+	}
+
+	sirfsoc_timer_count_disable(smp_processor_id());
+}
+
+static void sirfsoc_clocksource_suspend(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
+		sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+}
+
+static void sirfsoc_clocksource_resume(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
+		writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
+		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
+		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
+
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+}
+
+static struct clock_event_device sirfsoc_clockevent = {
+	.name = "sirfsoc_clockevent",
+	.rating = 200,
+	.features = CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode = sirfsoc_timer_set_mode,
+	.set_next_event = sirfsoc_timer_set_next_event,
+};
+
+static struct clocksource sirfsoc_clocksource = {
+	.name = "sirfsoc_clocksource",
+	.rating = 200,
+	.mask = CLOCKSOURCE_MASK(64),
+	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	.read = sirfsoc_timer_read,
+	.suspend = sirfsoc_clocksource_suspend,
+	.resume = sirfsoc_clocksource_resume,
+};
+
+static struct irqaction sirfsoc_timer_irq = {
+	.name = "sirfsoc_timer0",
+	.flags = IRQF_TIMER | IRQF_NOBALANCING,
+	.handler = sirfsoc_timer_interrupt,
+	.dev_id = &sirfsoc_clockevent,
+};
+
+#ifdef CONFIG_LOCAL_TIMERS
+
+static struct irqaction sirfsoc_timer1_irq = {
+	.name = "sirfsoc_timer1",
+	.flags = IRQF_TIMER | IRQF_NOBALANCING,
+	.handler = sirfsoc_timer_interrupt,
+};
+
+static int __cpuinit sirfsoc_local_timer_setup(struct clock_event_device *ce)
+{
+	/* Use existing clock_event for cpu 0 */
+	if (!smp_processor_id())
+		return 0;
+
+	ce->irq = sirfsoc_timer1_irq.irq;
+	ce->name = "local_timer";
+	ce->features = sirfsoc_clockevent.features;
+	ce->rating = sirfsoc_clockevent.rating;
+	ce->set_mode = sirfsoc_timer_set_mode;
+	ce->set_next_event = sirfsoc_timer_set_next_event;
+	ce->shift = sirfsoc_clockevent.shift;
+	ce->mult = sirfsoc_clockevent.mult;
+	ce->max_delta_ns = sirfsoc_clockevent.max_delta_ns;
+	ce->min_delta_ns = sirfsoc_clockevent.min_delta_ns;
+
+	sirfsoc_timer1_irq.dev_id = ce;
+	BUG_ON(setup_irq(ce->irq, &sirfsoc_timer1_irq));
+	irq_set_affinity(sirfsoc_timer1_irq.irq, cpumask_of(1));
+
+	clockevents_register_device(ce);
+	return 0;
+}
+
+static void sirfsoc_local_timer_stop(struct clock_event_device *ce)
+{
+	sirfsoc_timer_count_disable(1);
+
+	remove_irq(sirfsoc_timer1_irq.irq, &sirfsoc_timer1_irq);
+}
+
+static struct local_timer_ops sirfsoc_local_timer_ops __cpuinitdata = {
+	.setup	= sirfsoc_local_timer_setup,
+	.stop	= sirfsoc_local_timer_stop,
+};
+#endif /* CONFIG_LOCAL_TIMERS */
+
+static void __init sirfsoc_clockevent_init(void)
+{
+	clockevents_calc_mult_shift(&sirfsoc_clockevent, CLOCK_TICK_RATE, 60);
+
+	sirfsoc_clockevent.max_delta_ns =
+		clockevent_delta2ns(-2, &sirfsoc_clockevent);
+	sirfsoc_clockevent.min_delta_ns =
+		clockevent_delta2ns(2, &sirfsoc_clockevent);
+
+	sirfsoc_clockevent.cpumask = cpumask_of(0);
+	clockevents_register_device(&sirfsoc_clockevent);
+#ifdef CONFIG_LOCAL_TIMERS
+	local_timer_register(&sirfsoc_local_timer_ops);
+#endif
+}
+
+/* initialize the kernel jiffy timer source */
+static void __init sirfsoc_marco_timer_init(void)
+{
+	unsigned long rate;
+	u32 timer_div;
+	struct clk *clk;
+
+	/* timer's input clock is io clock */
+	clk = clk_get_sys("io", NULL);
+
+	BUG_ON(IS_ERR(clk));
+	rate = clk_get_rate(clk);
+
+	BUG_ON(rate < CLOCK_TICK_RATE);
+	BUG_ON(rate % CLOCK_TICK_RATE);
+
+	/* Initialize the timer dividers */
+	timer_div = rate / CLOCK_TICK_RATE - 1;
+	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);
+	writel_relaxed(timer_div << 16, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL);
+
+	/* Initialize timer counters to 0 */
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1);
+
+	/* Clear all interrupts */
+	writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
+
+	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));
+
+	BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));
+
+	sirfsoc_clockevent_init();
+}
+
+static void __init sirfsoc_of_timer_init(struct device_node *np)
+{
+	sirfsoc_timer_base = of_iomap(np, 0);
+	if (!sirfsoc_timer_base)
+		panic("unable to map timer cpu registers\n");
+
+	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
+	if (!sirfsoc_timer_irq.irq)
+		panic("No irq passed for timer0 via DT\n");
+
+#ifdef CONFIG_LOCAL_TIMERS
+	sirfsoc_timer1_irq.irq = irq_of_parse_and_map(np, 1);
+	if (!sirfsoc_timer1_irq.irq)
+		panic("No irq passed for timer1 via DT\n");
+#endif
+
+	sirfsoc_marco_timer_init();
+}
+CLOCKSOURCE_OF_DECLARE(sirfsoc_marco_timer, "sirf,marco-tick", sirfsoc_of_timer_init );
diff --git a/drivers/clocksource/timer-prima2.c b/drivers/clocksource/timer-prima2.c
new file mode 100644
index 000000000000..760882665d7a
--- /dev/null
+++ b/drivers/clocksource/timer-prima2.c
@@ -0,0 +1,215 @@
+/*
+ * System timer for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <asm/sched_clock.h>
+#include <asm/mach/time.h>
+
+#define SIRFSOC_TIMER_COUNTER_LO	0x0000
+#define SIRFSOC_TIMER_COUNTER_HI	0x0004
+#define SIRFSOC_TIMER_MATCH_0		0x0008
+#define SIRFSOC_TIMER_MATCH_1		0x000C
+#define SIRFSOC_TIMER_MATCH_2		0x0010
+#define SIRFSOC_TIMER_MATCH_3		0x0014
+#define SIRFSOC_TIMER_MATCH_4		0x0018
+#define SIRFSOC_TIMER_MATCH_5		0x001C
+#define SIRFSOC_TIMER_STATUS		0x0020
+#define SIRFSOC_TIMER_INT_EN		0x0024
+#define SIRFSOC_TIMER_WATCHDOG_EN	0x0028
+#define SIRFSOC_TIMER_DIV		0x002C
+#define SIRFSOC_TIMER_LATCH		0x0030
+#define SIRFSOC_TIMER_LATCHED_LO	0x0034
+#define SIRFSOC_TIMER_LATCHED_HI	0x0038
+
+#define SIRFSOC_TIMER_WDT_INDEX		5
+
+#define SIRFSOC_TIMER_LATCH_BIT	 BIT(0)
+
+#define SIRFSOC_TIMER_REG_CNT 11
+
+static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
+	SIRFSOC_TIMER_MATCH_0, SIRFSOC_TIMER_MATCH_1, SIRFSOC_TIMER_MATCH_2,
+	SIRFSOC_TIMER_MATCH_3, SIRFSOC_TIMER_MATCH_4, SIRFSOC_TIMER_MATCH_5,
+	SIRFSOC_TIMER_INT_EN, SIRFSOC_TIMER_WATCHDOG_EN, SIRFSOC_TIMER_DIV,
+	SIRFSOC_TIMER_LATCHED_LO, SIRFSOC_TIMER_LATCHED_HI,
+};
+
+static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
+
+static void __iomem *sirfsoc_timer_base;
+
+/* timer0 interrupt handler */
+static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+
+	WARN_ON(!(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_STATUS) & BIT(0)));
+
+	/* clear timer0 interrupt */
+	writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+/* read 64-bit timer counter */
+static cycle_t sirfsoc_timer_read(struct clocksource *cs)
+{
+	u64 cycles;
+
+	/* latch the 64-bit timer counter */
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_HI);
+	cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+	return cycles;
+}
+
+static int sirfsoc_timer_set_next_event(unsigned long delta,
+	struct clock_event_device *ce)
+{
+	unsigned long now, next;
+
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+	next = now + delta;
+	writel_relaxed(next, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0);
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+	return next - now > delta ? -ETIME : 0;
+}
+
+static void sirfsoc_timer_set_mode(enum clock_event_mode mode,
+	struct clock_event_device *ce)
+{
+	u32 val = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		WARN_ON(1);
+		break;
+	case CLOCK_EVT_MODE_ONESHOT:
+		writel_relaxed(val | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+		break;
+	case CLOCK_EVT_MODE_SHUTDOWN:
+		writel_relaxed(val & ~BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+		break;
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_RESUME:
+		break;
+	}
+}
+
+static void sirfsoc_clocksource_suspend(struct clocksource *cs)
+{
+	int i;
+
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT, sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
+		sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+}
+
+static void sirfsoc_clocksource_resume(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
+		writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2], sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1], sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+}
+
+static struct clock_event_device sirfsoc_clockevent = {
+	.name = "sirfsoc_clockevent",
+	.rating = 200,
+	.features = CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode = sirfsoc_timer_set_mode,
+	.set_next_event = sirfsoc_timer_set_next_event,
+};
+
+static struct clocksource sirfsoc_clocksource = {
+	.name = "sirfsoc_clocksource",
+	.rating = 200,
+	.mask = CLOCKSOURCE_MASK(64),
+	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	.read = sirfsoc_timer_read,
+	.suspend = sirfsoc_clocksource_suspend,
+	.resume = sirfsoc_clocksource_resume,
+};
+
+static struct irqaction sirfsoc_timer_irq = {
+	.name = "sirfsoc_timer0",
+	.flags = IRQF_TIMER,
+	.irq = 0,
+	.handler = sirfsoc_timer_interrupt,
+	.dev_id = &sirfsoc_clockevent,
+};
+
+/* Overwrite weak default sched_clock with more precise one */
+static u32 notrace sirfsoc_read_sched_clock(void)
+{
+	return (u32)(sirfsoc_timer_read(NULL) & 0xffffffff);
+}
+
+static void __init sirfsoc_clockevent_init(void)
+{
+	sirfsoc_clockevent.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&sirfsoc_clockevent, CLOCK_TICK_RATE,
+					2, -2);
+}
+
+/* initialize the kernel jiffy timer source */
+static void __init sirfsoc_prima2_timer_init(struct device_node *np)
+{
+	unsigned long rate;
+	struct clk *clk;
+
+	/* timer's input clock is io clock */
+	clk = clk_get_sys("io", NULL);
+
+	BUG_ON(IS_ERR(clk));
+
+	rate = clk_get_rate(clk);
+
+	BUG_ON(rate < CLOCK_TICK_RATE);
+	BUG_ON(rate % CLOCK_TICK_RATE);
+
+	sirfsoc_timer_base = of_iomap(np, 0);
+	if (!sirfsoc_timer_base)
+		panic("unable to map timer cpu registers\n");
+
+	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
+
+	writel_relaxed(rate / CLOCK_TICK_RATE / 2 - 1, sirfsoc_timer_base + SIRFSOC_TIMER_DIV);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+	writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, CLOCK_TICK_RATE));
+
+	setup_sched_clock(sirfsoc_read_sched_clock, 32, CLOCK_TICK_RATE);
+
+	BUG_ON(setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq));
+
+	sirfsoc_clockevent_init();
+}
+CLOCKSOURCE_OF_DECLARE(sirfsoc_prima2_timer, "sirf,prima2-tick", sirfsoc_prima2_timer_init);