1 files changed, 136 insertions, 32 deletions

diff --git a/arch/arm/mach-at91/at91sam926x_time.c b/arch/arm/mach-at91/at91sam926x_time.c
index 608a63240b6..0a9e2fc8f79 100644
--- a/arch/arm/mach-at91/at91sam926x_time.c
+++ b/arch/arm/mach-at91/at91sam926x_time.c
@@ -14,18 +14,43 @@
 #include <linux/kernel.h>
 #include <linux/clk.h>
 #include <linux/clockchips.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
 
 #include <asm/mach/time.h>
+#include <mach/hardware.h>
 
-#include <mach/at91_pit.h>
+#define AT91_PIT_MR		0x00			/* Mode Register */
+#define		AT91_PIT_PITIEN		(1 << 25)		/* Timer Interrupt Enable */
+#define		AT91_PIT_PITEN		(1 << 24)		/* Timer Enabled */
+#define		AT91_PIT_PIV		(0xfffff)		/* Periodic Interval Value */
 
+#define AT91_PIT_SR		0x04			/* Status Register */
+#define		AT91_PIT_PITS		(1 << 0)		/* Timer Status */
+
+#define AT91_PIT_PIVR		0x08			/* Periodic Interval Value Register */
+#define AT91_PIT_PIIR		0x0c			/* Periodic Interval Image Register */
+#define		AT91_PIT_PICNT		(0xfff << 20)		/* Interval Counter */
+#define		AT91_PIT_CPIV		(0xfffff)		/* Inverval Value */
 
 #define PIT_CPIV(x)	((x) & AT91_PIT_CPIV)
 #define PIT_PICNT(x)	(((x) & AT91_PIT_PICNT) >> 20)
 
 static u32 pit_cycle;		/* write-once */
 static u32 pit_cnt;		/* access only w/system irq blocked */
+static void __iomem *pit_base_addr __read_mostly;
+static struct clk *mck;
 
+static inline unsigned int pit_read(unsigned int reg_offset)
+{
+	return __raw_readl(pit_base_addr + reg_offset);
+}
+
+static inline void pit_write(unsigned int reg_offset, unsigned long value)
+{
+	__raw_writel(value, pit_base_addr + reg_offset);
+}
 
 /*
  * Clocksource:  just a monotonic counter of MCK/16 cycles.
@@ -39,7 +64,7 @@ static cycle_t read_pit_clk(struct clocksource *cs)
 
 	raw_local_irq_save(flags);
 	elapsed = pit_cnt;
-	t = at91_sys_read(AT91_PIT_PIIR);
+	t = pit_read(AT91_PIT_PIIR);
 	raw_local_irq_restore(flags);
 
 	elapsed += PIT_PICNT(t) * pit_cycle;
@@ -51,7 +76,6 @@ static struct clocksource pit_clk = {
 	.name		= "pit",
 	.rating		= 175,
 	.read		= read_pit_clk,
-	.shift		= 20,
 	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
@@ -65,8 +89,8 @@ pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
 		/* update clocksource counter */
-		pit_cnt += pit_cycle * PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
-		at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
+		pit_cnt += pit_cycle * PIT_PICNT(pit_read(AT91_PIT_PIVR));
+		pit_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN
 				| AT91_PIT_PITIEN);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
@@ -75,19 +99,45 @@ pit_clkevt_mode(enum clock_event_mode mode, struct clock_event_device *dev)
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	case CLOCK_EVT_MODE_UNUSED:
 		/* disable irq, leaving the clocksource active */
-		at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
+		pit_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
 		break;
 	case CLOCK_EVT_MODE_RESUME:
 		break;
 	}
 }
 
+static void at91sam926x_pit_suspend(struct clock_event_device *cedev)
+{
+	/* Disable timer */
+	pit_write(AT91_PIT_MR, 0);
+}
+
+static void at91sam926x_pit_reset(void)
+{
+	/* Disable timer and irqs */
+	pit_write(AT91_PIT_MR, 0);
+
+	/* Clear any pending interrupts, wait for PIT to stop counting */
+	while (PIT_CPIV(pit_read(AT91_PIT_PIVR)) != 0)
+		cpu_relax();
+
+	/* Start PIT but don't enable IRQ */
+	pit_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
+}
+
+static void at91sam926x_pit_resume(struct clock_event_device *cedev)
+{
+	at91sam926x_pit_reset();
+}
+
 static struct clock_event_device pit_clkevt = {
 	.name		= "pit",
 	.features	= CLOCK_EVT_FEAT_PERIODIC,
 	.shift		= 32,
 	.rating		= 100,
 	.set_mode	= pit_clkevt_mode,
+	.suspend	= at91sam926x_pit_suspend,
+	.resume		= at91sam926x_pit_resume,
 };
 
 
@@ -104,11 +154,11 @@ static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
 
 	/* The PIT interrupt may be disabled, and is shared */
 	if ((pit_clkevt.mode == CLOCK_EVT_MODE_PERIODIC)
-			&& (at91_sys_read(AT91_PIT_SR) & AT91_PIT_PITS)) {
+			&& (pit_read(AT91_PIT_SR) & AT91_PIT_PITS)) {
 		unsigned nr_ticks;
 
 		/* Get number of ticks performed before irq, and ack it */
-		nr_ticks = PIT_PICNT(at91_sys_read(AT91_PIT_PIVR));
+		nr_ticks = PIT_PICNT(pit_read(AT91_PIT_PIVR));
 		do {
 			pit_cnt += pit_cycle;
 			pit_clkevt.event_handler(&pit_clkevt);
@@ -123,36 +173,84 @@ static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
 
 static struct irqaction at91sam926x_pit_irq = {
 	.name		= "at91_tick",
-	.flags		= IRQF_SHARED | IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
-	.handler	= at91sam926x_pit_interrupt
+	.flags		= IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= at91sam926x_pit_interrupt,
+	.irq		= NR_IRQS_LEGACY + AT91_ID_SYS,
 };
 
-static void at91sam926x_pit_reset(void)
+#ifdef CONFIG_OF
+static struct of_device_id pit_timer_ids[] = {
+	{ .compatible = "atmel,at91sam9260-pit" },
+	{ /* sentinel */ }
+};
+
+static int __init of_at91sam926x_pit_init(void)
 {
-	/* Disable timer and irqs */
-	at91_sys_write(AT91_PIT_MR, 0);
+	struct device_node	*np;
+	int			ret;
 
-	/* Clear any pending interrupts, wait for PIT to stop counting */
-	while (PIT_CPIV(at91_sys_read(AT91_PIT_PIVR)) != 0)
-		cpu_relax();
+	np = of_find_matching_node(NULL, pit_timer_ids);
+	if (!np)
+		goto err;
 
-	/* Start PIT but don't enable IRQ */
-	at91_sys_write(AT91_PIT_MR, (pit_cycle - 1) | AT91_PIT_PITEN);
+	pit_base_addr = of_iomap(np, 0);
+	if (!pit_base_addr)
+		goto node_err;
+
+	mck = of_clk_get(np, 0);
+
+	/* Get the interrupts property */
+	ret = irq_of_parse_and_map(np, 0);
+	if (!ret) {
+		pr_crit("AT91: PIT: Unable to get IRQ from DT\n");
+		if (!IS_ERR(mck))
+			clk_put(mck);
+		goto ioremap_err;
+	}
+	at91sam926x_pit_irq.irq = ret;
+
+	of_node_put(np);
+
+	return 0;
+
+ioremap_err:
+	iounmap(pit_base_addr);
+node_err:
+	of_node_put(np);
+err:
+	return -EINVAL;
 }
+#else
+static int __init of_at91sam926x_pit_init(void)
+{
+	return -EINVAL;
+}
+#endif
 
 /*
  * Set up both clocksource and clockevent support.
  */
-static void __init at91sam926x_pit_init(void)
+void __init at91sam926x_pit_init(void)
 {
 	unsigned long	pit_rate;
 	unsigned	bits;
+	int		ret;
+
+	mck = ERR_PTR(-ENOENT);
+
+	/* For device tree enabled device: initialize here */
+	of_at91sam926x_pit_init();
 
 	/*
 	 * Use our actual MCK to figure out how many MCK/16 ticks per
 	 * 1/HZ period (instead of a compile-time constant LATCH).
 	 */
-	pit_rate = clk_get_rate(clk_get(NULL, "mck")) / 16;
+	if (IS_ERR(mck))
+		mck = clk_get(NULL, "mck");
+
+	if (IS_ERR(mck))
+		panic("AT91: PIT: Unable to get mck clk\n");
+	pit_rate = clk_get_rate(mck) / 16;
 	pit_cycle = (pit_rate + HZ/2) / HZ;
 	WARN_ON(((pit_cycle - 1) & ~AT91_PIT_PIV) != 0);
 
@@ -163,13 +261,14 @@ static void __init at91sam926x_pit_init(void)
 	 * Register clocksource.  The high order bits of PIV are unused,
 	 * so this isn't a 32-bit counter unless we get clockevent irqs.
 	 */
-	pit_clk.mult = clocksource_hz2mult(pit_rate, pit_clk.shift);
 	bits = 12 /* PICNT */ + ilog2(pit_cycle) /* PIV */;
 	pit_clk.mask = CLOCKSOURCE_MASK(bits);
-	clocksource_register(&pit_clk);
+	clocksource_register_hz(&pit_clk, pit_rate);
 
 	/* Set up irq handler */
-	setup_irq(AT91_ID_SYS, &at91sam926x_pit_irq);
+	ret = setup_irq(at91sam926x_pit_irq.irq, &at91sam926x_pit_irq);
+	if (ret)
+		pr_crit("AT91: PIT: Unable to setup IRQ\n");
 
 	/* Set up and register clockevents */
 	pit_clkevt.mult = div_sc(pit_rate, NSEC_PER_SEC, pit_clkevt.shift);
@@ -177,14 +276,19 @@ static void __init at91sam926x_pit_init(void)
 	clockevents_register_device(&pit_clkevt);
 }
 
-static void at91sam926x_pit_suspend(void)
+void __init at91sam926x_ioremap_pit(u32 addr)
 {
-	/* Disable timer */
-	at91_sys_write(AT91_PIT_MR, 0);
-}
+#if defined(CONFIG_OF)
+	struct device_node *np =
+		of_find_matching_node(NULL, pit_timer_ids);
 
-struct sys_timer at91sam926x_timer = {
-	.init		= at91sam926x_pit_init,
-	.suspend	= at91sam926x_pit_suspend,
-	.resume		= at91sam926x_pit_reset,
-};
+	if (np) {
+		of_node_put(np);
+		return;
+	}
+#endif
+	pit_base_addr = ioremap(addr, 16);
+
+	if (!pit_base_addr)
+		panic("Impossible to ioremap PIT\n");
+}