Merge remote-tracking branch 'tip/timers/core' into fordlezcano/3.13/sched-clock64-conversion

Update to tip/timers/core and resolve minor conflict.

Conflicts:
	drivers/clocksource/samsung_pwm_timer.c

Signed-off-by: John Stultz <john.stultz@linaro.org>

1 files changed, 121 insertions, 104 deletions

diff --git a/drivers/clocksource/time-armada-370-xp.c b/drivers/clocksource/time-armada-370-xp.c
index 2bec8dca74b..d8e47e50278 100644
--- a/drivers/clocksource/time-armada-370-xp.c
+++ b/drivers/clocksource/time-armada-370-xp.c
@@ -13,12 +13,26 @@
  *
  * Timer 0 is used as free-running clocksource, while timer 1 is
  * used as clock_event_device.
+ *
+ * ---
+ * Clocksource driver for Armada 370 and Armada XP SoC.
+ * This driver implements one compatible string for each SoC, given
+ * each has its own characteristics:
+ *
+ *   * Armada 370 has no 25 MHz fixed timer.
+ *
+ *   * Armada XP cannot work properly without such 25 MHz fixed timer as
+ *     doing otherwise leads to using a clocksource whose frequency varies
+ *     when doing cpufreq frequency changes.
+ *
+ * See Documentation/devicetree/bindings/timer/marvell,armada-370-xp-timer.txt
  */
 
 #include <linux/init.h>
 #include <linux/platform_device.h>
 #include <linux/kernel.h>
 #include <linux/clk.h>
+#include <linux/cpu.h>
 #include <linux/timer.h>
 #include <linux/clockchips.h>
 #include <linux/interrupt.h>
@@ -28,20 +42,19 @@
 #include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/sched_clock.h>
-
-#include <asm/localtimer.h>
 #include <linux/percpu.h>
+
 /*
  * Timer block registers.
  */
 #define TIMER_CTRL_OFF		0x0000
-#define  TIMER0_EN		 0x0001
-#define  TIMER0_RELOAD_EN	 0x0002
-#define  TIMER0_25MHZ            0x0800
+#define  TIMER0_EN		 BIT(0)
+#define  TIMER0_RELOAD_EN	 BIT(1)
+#define  TIMER0_25MHZ            BIT(11)
 #define  TIMER0_DIV(div)         ((div) << 19)
-#define  TIMER1_EN		 0x0004
-#define  TIMER1_RELOAD_EN	 0x0008
-#define  TIMER1_25MHZ            0x1000
+#define  TIMER1_EN		 BIT(2)
+#define  TIMER1_RELOAD_EN	 BIT(3)
+#define  TIMER1_25MHZ            BIT(12)
 #define  TIMER1_DIV(div)         ((div) << 22)
 #define TIMER_EVENTS_STATUS	0x0004
 #define  TIMER0_CLR_MASK         (~0x1)
@@ -69,7 +82,19 @@ static bool timer25Mhz = true;
  */
 static u32 ticks_per_jiffy;
 
-static struct clock_event_device __percpu **percpu_armada_370_xp_evt;
+static struct clock_event_device __percpu *armada_370_xp_evt;
+
+static void timer_ctrl_clrset(u32 clr, u32 set)
+{
+	writel((readl(timer_base + TIMER_CTRL_OFF) & ~clr) | set,
+		timer_base + TIMER_CTRL_OFF);
+}
+
+static void local_timer_ctrl_clrset(u32 clr, u32 set)
+{
+	writel((readl(local_base + TIMER_CTRL_OFF) & ~clr) | set,
+		local_base + TIMER_CTRL_OFF);
+}
 
 static u64 notrace armada_370_xp_read_sched_clock(void)
 {
@@ -83,7 +108,6 @@ static int
 armada_370_xp_clkevt_next_event(unsigned long delta,
 				struct clock_event_device *dev)
 {
-	u32 u;
 	/*
 	 * Clear clockevent timer interrupt.
 	 */
@@ -97,11 +121,8 @@ armada_370_xp_clkevt_next_event(unsigned long delta,
 	/*
 	 * Enable the timer.
 	 */
-	u = readl(local_base + TIMER_CTRL_OFF);
-	u = ((u & ~TIMER0_RELOAD_EN) | TIMER0_EN |
-	     TIMER0_DIV(TIMER_DIVIDER_SHIFT));
-	writel(u, local_base + TIMER_CTRL_OFF);
-
+	local_timer_ctrl_clrset(TIMER0_RELOAD_EN,
+				TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT));
 	return 0;
 }
 
@@ -109,8 +130,6 @@ static void
 armada_370_xp_clkevt_mode(enum clock_event_mode mode,
 			  struct clock_event_device *dev)
 {
-	u32 u;
-
 	if (mode == CLOCK_EVT_MODE_PERIODIC) {
 
 		/*
@@ -122,18 +141,14 @@ armada_370_xp_clkevt_mode(enum clock_event_mode mode,
 		/*
 		 * Enable timer.
 		 */
-
-		u = readl(local_base + TIMER_CTRL_OFF);
-
-		writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
-			TIMER0_DIV(TIMER_DIVIDER_SHIFT)),
-			local_base + TIMER_CTRL_OFF);
+		local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN |
+					   TIMER0_EN |
+					   TIMER0_DIV(TIMER_DIVIDER_SHIFT));
 	} else {
 		/*
 		 * Disable timer.
 		 */
-		u = readl(local_base + TIMER_CTRL_OFF);
-		writel(u & ~TIMER0_EN, local_base + TIMER_CTRL_OFF);
+		local_timer_ctrl_clrset(TIMER0_EN, 0);
 
 		/*
 		 * ACK pending timer interrupt.
@@ -142,21 +157,14 @@ armada_370_xp_clkevt_mode(enum clock_event_mode mode,
 	}
 }
 
-static struct clock_event_device armada_370_xp_clkevt = {
-	.name		= "armada_370_xp_per_cpu_tick",
-	.features	= CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
-	.shift		= 32,
-	.rating		= 300,
-	.set_next_event	= armada_370_xp_clkevt_next_event,
-	.set_mode	= armada_370_xp_clkevt_mode,
-};
+static int armada_370_xp_clkevt_irq;
 
 static irqreturn_t armada_370_xp_timer_interrupt(int irq, void *dev_id)
 {
 	/*
 	 * ACK timer interrupt and call event handler.
 	 */
-	struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
+	struct clock_event_device *evt = dev_id;
 
 	writel(TIMER0_CLR_MASK, local_base + LCL_TIMER_EVENTS_STATUS);
 	evt->event_handler(evt);
@@ -167,91 +175,83 @@ static irqreturn_t armada_370_xp_timer_interrupt(int irq, void *dev_id)
 /*
  * Setup the local clock events for a CPU.
  */
-static int __cpuinit armada_370_xp_timer_setup(struct clock_event_device *evt)
+static int armada_370_xp_timer_setup(struct clock_event_device *evt)
 {
-	u32 u;
+	u32 clr = 0, set = 0;
 	int cpu = smp_processor_id();
 
-	/* Use existing clock_event for cpu 0 */
-	if (!smp_processor_id())
-		return 0;
-
-	u = readl(local_base + TIMER_CTRL_OFF);
 	if (timer25Mhz)
-		writel(u | TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
+		set = TIMER0_25MHZ;
 	else
-		writel(u & ~TIMER0_25MHZ, local_base + TIMER_CTRL_OFF);
-
-	evt->name		= armada_370_xp_clkevt.name;
-	evt->irq		= armada_370_xp_clkevt.irq;
-	evt->features		= armada_370_xp_clkevt.features;
-	evt->shift		= armada_370_xp_clkevt.shift;
-	evt->rating		= armada_370_xp_clkevt.rating,
+		clr = TIMER0_25MHZ;
+	local_timer_ctrl_clrset(clr, set);
+
+	evt->name		= "armada_370_xp_per_cpu_tick",
+	evt->features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC;
+	evt->shift		= 32,
+	evt->rating		= 300,
 	evt->set_next_event	= armada_370_xp_clkevt_next_event,
 	evt->set_mode		= armada_370_xp_clkevt_mode,
+	evt->irq		= armada_370_xp_clkevt_irq;
 	evt->cpumask		= cpumask_of(cpu);
 
-	*__this_cpu_ptr(percpu_armada_370_xp_evt) = evt;
-
 	clockevents_config_and_register(evt, timer_clk, 1, 0xfffffffe);
 	enable_percpu_irq(evt->irq, 0);
 
 	return 0;
 }
 
-static void  armada_370_xp_timer_stop(struct clock_event_device *evt)
+static void armada_370_xp_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 armada_370_xp_local_timer_ops __cpuinitdata = {
-	.setup	= armada_370_xp_timer_setup,
-	.stop	=  armada_370_xp_timer_stop,
+static int armada_370_xp_timer_cpu_notify(struct notifier_block *self,
+					   unsigned long action, void *hcpu)
+{
+	/*
+	 * Grab cpu pointer in each case to avoid spurious
+	 * preemptible warnings
+	 */
+	switch (action & ~CPU_TASKS_FROZEN) {
+	case CPU_STARTING:
+		armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt));
+		break;
+	case CPU_DYING:
+		armada_370_xp_timer_stop(this_cpu_ptr(armada_370_xp_evt));
+		break;
+	}
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block armada_370_xp_timer_cpu_nb = {
+	.notifier_call = armada_370_xp_timer_cpu_notify,
 };
 
-void __init armada_370_xp_timer_init(void)
+static void __init armada_370_xp_timer_common_init(struct device_node *np)
 {
-	u32 u;
-	struct device_node *np;
+	u32 clr = 0, set = 0;
 	int res;
 
-	np = of_find_compatible_node(NULL, NULL, "marvell,armada-370-xp-timer");
 	timer_base = of_iomap(np, 0);
 	WARN_ON(!timer_base);
 	local_base = of_iomap(np, 1);
 
-	if (of_find_property(np, "marvell,timer-25Mhz", NULL)) {
-		/* The fixed 25MHz timer is available so let's use it */
-		u = readl(local_base + TIMER_CTRL_OFF);
-		writel(u | TIMER0_25MHZ,
-		       local_base + TIMER_CTRL_OFF);
-		u = readl(timer_base + TIMER_CTRL_OFF);
-		writel(u | TIMER0_25MHZ,
-		       timer_base + TIMER_CTRL_OFF);
-		timer_clk = 25000000;
-	} else {
-		unsigned long rate = 0;
-		struct clk *clk = of_clk_get(np, 0);
-		WARN_ON(IS_ERR(clk));
-		rate =  clk_get_rate(clk);
-		u = readl(local_base + TIMER_CTRL_OFF);
-		writel(u & ~(TIMER0_25MHZ),
-		       local_base + TIMER_CTRL_OFF);
-
-		u = readl(timer_base + TIMER_CTRL_OFF);
-		writel(u & ~(TIMER0_25MHZ),
-		       timer_base + TIMER_CTRL_OFF);
-
-		timer_clk = rate / TIMER_DIVIDER;
-		timer25Mhz = false;
-	}
+	if (timer25Mhz)
+		set = TIMER0_25MHZ;		
+	else
+		clr = TIMER0_25MHZ;
+	timer_ctrl_clrset(clr, set);
+	local_timer_ctrl_clrset(clr, set);
 
 	/*
 	 * We use timer 0 as clocksource, and private(local) timer 0
 	 * for clockevents
 	 */
-	armada_370_xp_clkevt.irq = irq_of_parse_and_map(np, 4);
+	armada_370_xp_clkevt_irq = irq_of_parse_and_map(np, 4);
 
 	ticks_per_jiffy = (timer_clk + HZ / 2) / HZ;
 
@@ -267,35 +267,52 @@ void __init armada_370_xp_timer_init(void)
 	writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
 	writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
 
-	u = readl(timer_base + TIMER_CTRL_OFF);
-
-	writel((u | TIMER0_EN | TIMER0_RELOAD_EN |
-		TIMER0_DIV(TIMER_DIVIDER_SHIFT)), timer_base + TIMER_CTRL_OFF);
+	timer_ctrl_clrset(0, TIMER0_EN | TIMER0_RELOAD_EN |
+			     TIMER0_DIV(TIMER_DIVIDER_SHIFT));
 
 	clocksource_mmio_init(timer_base + TIMER0_VAL_OFF,
 			      "armada_370_xp_clocksource",
 			      timer_clk, 300, 32, clocksource_mmio_readl_down);
 
-	/* Register the clockevent on the private timer of CPU 0 */
-	armada_370_xp_clkevt.cpumask = cpumask_of(0);
-	clockevents_config_and_register(&armada_370_xp_clkevt,
-					timer_clk, 1, 0xfffffffe);
+	register_cpu_notifier(&armada_370_xp_timer_cpu_nb);
 
-	percpu_armada_370_xp_evt = alloc_percpu(struct clock_event_device *);
+	armada_370_xp_evt = alloc_percpu(struct clock_event_device);
 
 
 	/*
 	 * Setup clockevent timer (interrupt-driven).
 	 */
-	*__this_cpu_ptr(percpu_armada_370_xp_evt) = &armada_370_xp_clkevt;
-	res = request_percpu_irq(armada_370_xp_clkevt.irq,
+	res = request_percpu_irq(armada_370_xp_clkevt_irq,
 				armada_370_xp_timer_interrupt,
-				armada_370_xp_clkevt.name,
-				percpu_armada_370_xp_evt);
-	if (!res) {
-		enable_percpu_irq(armada_370_xp_clkevt.irq, 0);
-#ifdef CONFIG_LOCAL_TIMERS
-		local_timer_register(&armada_370_xp_local_timer_ops);
-#endif
-	}
+				"armada_370_xp_per_cpu_tick",
+				armada_370_xp_evt);
+	/* Immediately configure the timer on the boot CPU */
+	if (!res)
+		armada_370_xp_timer_setup(this_cpu_ptr(armada_370_xp_evt));
+}
+
+static void __init armada_xp_timer_init(struct device_node *np)
+{
+	struct clk *clk = of_clk_get_by_name(np, "fixed");
+
+	/* The 25Mhz fixed clock is mandatory, and must always be available */
+	BUG_ON(IS_ERR(clk));
+	timer_clk = clk_get_rate(clk);
+
+	armada_370_xp_timer_common_init(np);
+}
+CLOCKSOURCE_OF_DECLARE(armada_xp, "marvell,armada-xp-timer",
+		       armada_xp_timer_init);
+
+static void __init armada_370_timer_init(struct device_node *np)
+{
+	struct clk *clk = of_clk_get(np, 0);
+
+	BUG_ON(IS_ERR(clk));
+	timer_clk = clk_get_rate(clk) / TIMER_DIVIDER;
+	timer25Mhz = false;
+
+	armada_370_xp_timer_common_init(np);
 }
+CLOCKSOURCE_OF_DECLARE(armada_370, "marvell,armada-370-timer",
+		       armada_370_timer_init);