1 files changed, 225 insertions, 75 deletions

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 5dcbf90b8015..28aa4b7bb602 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -17,7 +17,7 @@
 #include <linux/irq.h>
 #include <linux/irqreturn.h>
 #include <linux/reset.h>
-#include <linux/sched_clock.h>
+#include <linux/slab.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
@@ -37,8 +37,31 @@
 
 #define TIMER_SYNC_TICKS	3
 
-static void __iomem *timer_base;
-static u32 ticks_per_jiffy;
+struct sun5i_timer {
+	void __iomem		*base;
+	struct clk		*clk;
+	struct notifier_block	clk_rate_cb;
+	u32			ticks_per_jiffy;
+};
+
+#define to_sun5i_timer(x) \
+	container_of(x, struct sun5i_timer, clk_rate_cb)
+
+struct sun5i_timer_clksrc {
+	struct sun5i_timer	timer;
+	struct clocksource	clksrc;
+};
+
+#define to_sun5i_timer_clksrc(x) \
+	container_of(x, struct sun5i_timer_clksrc, clksrc)
+
+struct sun5i_timer_clkevt {
+	struct sun5i_timer		timer;
+	struct clock_event_device	clkevt;
+};
+
+#define to_sun5i_timer_clkevt(x) \
+	container_of(x, struct sun5i_timer_clkevt, clkevt)
 
 /*
  * When we disable a timer, we need to wait at least for 2 cycles of
@@ -46,30 +69,30 @@ static u32 ticks_per_jiffy;
  * that is already setup and runs at the same frequency than the other
  * timers, and we never will be disabled.
  */
-static void sun5i_clkevt_sync(void)
+static void sun5i_clkevt_sync(struct sun5i_timer_clkevt *ce)
 {
-	u32 old = readl(timer_base + TIMER_CNTVAL_LO_REG(1));
+	u32 old = readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1));
 
-	while ((old - readl(timer_base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS)
+	while ((old - readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS)
 		cpu_relax();
 }
 
-static void sun5i_clkevt_time_stop(u8 timer)
+static void sun5i_clkevt_time_stop(struct sun5i_timer_clkevt *ce, u8 timer)
 {
-	u32 val = readl(timer_base + TIMER_CTL_REG(timer));
-	writel(val & ~TIMER_CTL_ENABLE, timer_base + TIMER_CTL_REG(timer));
+	u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
+	writel(val & ~TIMER_CTL_ENABLE, ce->timer.base + TIMER_CTL_REG(timer));
 
-	sun5i_clkevt_sync();
+	sun5i_clkevt_sync(ce);
 }
 
-static void sun5i_clkevt_time_setup(u8 timer, u32 delay)
+static void sun5i_clkevt_time_setup(struct sun5i_timer_clkevt *ce, u8 timer, u32 delay)
 {
-	writel(delay, timer_base + TIMER_INTVAL_LO_REG(timer));
+	writel(delay, ce->timer.base + TIMER_INTVAL_LO_REG(timer));
 }
 
-static void sun5i_clkevt_time_start(u8 timer, bool periodic)
+static void sun5i_clkevt_time_start(struct sun5i_timer_clkevt *ce, u8 timer, bool periodic)
 {
-	u32 val = readl(timer_base + TIMER_CTL_REG(timer));
+	u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
 
 	if (periodic)
 		val &= ~TIMER_CTL_ONESHOT;
@@ -77,80 +100,230 @@ static void sun5i_clkevt_time_start(u8 timer, bool periodic)
 		val |= TIMER_CTL_ONESHOT;
 
 	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
-	       timer_base + TIMER_CTL_REG(timer));
+	       ce->timer.base + TIMER_CTL_REG(timer));
 }
 
 static void sun5i_clkevt_mode(enum clock_event_mode mode,
-			      struct clock_event_device *clk)
+			      struct clock_event_device *clkevt)
 {
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
 	switch (mode) {
 	case CLOCK_EVT_MODE_PERIODIC:
-		sun5i_clkevt_time_stop(0);
-		sun5i_clkevt_time_setup(0, ticks_per_jiffy);
-		sun5i_clkevt_time_start(0, true);
+		sun5i_clkevt_time_stop(ce, 0);
+		sun5i_clkevt_time_setup(ce, 0, ce->timer.ticks_per_jiffy);
+		sun5i_clkevt_time_start(ce, 0, true);
 		break;
 	case CLOCK_EVT_MODE_ONESHOT:
-		sun5i_clkevt_time_stop(0);
-		sun5i_clkevt_time_start(0, false);
+		sun5i_clkevt_time_stop(ce, 0);
+		sun5i_clkevt_time_start(ce, 0, false);
 		break;
 	case CLOCK_EVT_MODE_UNUSED:
 	case CLOCK_EVT_MODE_SHUTDOWN:
 	default:
-		sun5i_clkevt_time_stop(0);
+		sun5i_clkevt_time_stop(ce, 0);
 		break;
 	}
 }
 
 static int sun5i_clkevt_next_event(unsigned long evt,
-				   struct clock_event_device *unused)
+				   struct clock_event_device *clkevt)
 {
-	sun5i_clkevt_time_stop(0);
-	sun5i_clkevt_time_setup(0, evt - TIMER_SYNC_TICKS);
-	sun5i_clkevt_time_start(0, false);
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
+	sun5i_clkevt_time_stop(ce, 0);
+	sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS);
+	sun5i_clkevt_time_start(ce, 0, false);
 
 	return 0;
 }
 
-static struct clock_event_device sun5i_clockevent = {
-	.name = "sun5i_tick",
-	.rating = 340,
-	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
-	.set_mode = sun5i_clkevt_mode,
-	.set_next_event = sun5i_clkevt_next_event,
-};
-
-
 static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
 {
-	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+	struct sun5i_timer_clkevt *ce = (struct sun5i_timer_clkevt *)dev_id;
 
-	writel(0x1, timer_base + TIMER_IRQ_ST_REG);
-	evt->event_handler(evt);
+	writel(0x1, ce->timer.base + TIMER_IRQ_ST_REG);
+	ce->clkevt.event_handler(&ce->clkevt);
 
 	return IRQ_HANDLED;
 }
 
-static struct irqaction sun5i_timer_irq = {
-	.name = "sun5i_timer0",
-	.flags = IRQF_TIMER | IRQF_IRQPOLL,
-	.handler = sun5i_timer_interrupt,
-	.dev_id = &sun5i_clockevent,
-};
+static cycle_t sun5i_clksrc_read(struct clocksource *clksrc)
+{
+	struct sun5i_timer_clksrc *cs = to_sun5i_timer_clksrc(clksrc);
+
+	return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1));
+}
 
-static u64 sun5i_timer_sched_read(void)
+static int sun5i_rate_cb_clksrc(struct notifier_block *nb,
+				unsigned long event, void *data)
 {
-	return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
+	struct clk_notifier_data *ndata = data;
+	struct sun5i_timer *timer = to_sun5i_timer(nb);
+	struct sun5i_timer_clksrc *cs = container_of(timer, struct sun5i_timer_clksrc, timer);
+
+	switch (event) {
+	case PRE_RATE_CHANGE:
+		clocksource_unregister(&cs->clksrc);
+		break;
+
+	case POST_RATE_CHANGE:
+		clocksource_register_hz(&cs->clksrc, ndata->new_rate);
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init sun5i_setup_clocksource(struct device_node *node,
+					  void __iomem *base,
+					  struct clk *clk, int irq)
+{
+	struct sun5i_timer_clksrc *cs;
+	unsigned long rate;
+	int ret;
+
+	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clock\n");
+		goto err_free;
+	}
+
+	rate = clk_get_rate(clk);
+
+	cs->timer.base = base;
+	cs->timer.clk = clk;
+	cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc;
+	cs->timer.clk_rate_cb.next = NULL;
+
+	ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb);
+	if (ret) {
+		pr_err("Unable to register clock notifier.\n");
+		goto err_disable_clk;
+	}
+
+	writel(~0, base + TIMER_INTVAL_LO_REG(1));
+	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+	       base + TIMER_CTL_REG(1));
+
+	cs->clksrc.name = node->name;
+	cs->clksrc.rating = 340;
+	cs->clksrc.read = sun5i_clksrc_read;
+	cs->clksrc.mask = CLOCKSOURCE_MASK(32);
+	cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	ret = clocksource_register_hz(&cs->clksrc, rate);
+	if (ret) {
+		pr_err("Couldn't register clock source.\n");
+		goto err_remove_notifier;
+	}
+
+	return 0;
+
+err_remove_notifier:
+	clk_notifier_unregister(clk, &cs->timer.clk_rate_cb);
+err_disable_clk:
+	clk_disable_unprepare(clk);
+err_free:
+	kfree(cs);
+	return ret;
+}
+
+static int sun5i_rate_cb_clkevt(struct notifier_block *nb,
+				unsigned long event, void *data)
+{
+	struct clk_notifier_data *ndata = data;
+	struct sun5i_timer *timer = to_sun5i_timer(nb);
+	struct sun5i_timer_clkevt *ce = container_of(timer, struct sun5i_timer_clkevt, timer);
+
+	if (event == POST_RATE_CHANGE) {
+		clockevents_update_freq(&ce->clkevt, ndata->new_rate);
+		ce->timer.ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem *base,
+					 struct clk *clk, int irq)
+{
+	struct sun5i_timer_clkevt *ce;
+	unsigned long rate;
+	int ret;
+	u32 val;
+
+	ce = kzalloc(sizeof(*ce), GFP_KERNEL);
+	if (!ce)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clock\n");
+		goto err_free;
+	}
+
+	rate = clk_get_rate(clk);
+
+	ce->timer.base = base;
+	ce->timer.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+	ce->timer.clk = clk;
+	ce->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clkevt;
+	ce->timer.clk_rate_cb.next = NULL;
+
+	ret = clk_notifier_register(clk, &ce->timer.clk_rate_cb);
+	if (ret) {
+		pr_err("Unable to register clock notifier.\n");
+		goto err_disable_clk;
+	}
+
+	ce->clkevt.name = node->name;
+	ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	ce->clkevt.set_next_event = sun5i_clkevt_next_event;
+	ce->clkevt.set_mode = sun5i_clkevt_mode;
+	ce->clkevt.rating = 340;
+	ce->clkevt.irq = irq;
+	ce->clkevt.cpumask = cpu_possible_mask;
+
+	/* Enable timer0 interrupt */
+	val = readl(base + TIMER_IRQ_EN_REG);
+	writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG);
+
+	clockevents_config_and_register(&ce->clkevt, rate,
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			  "sun5i_timer0", ce);
+	if (ret) {
+		pr_err("Unable to register interrupt\n");
+		goto err_remove_notifier;
+	}
+
+	return 0;
+
+err_remove_notifier:
+	clk_notifier_unregister(clk, &ce->timer.clk_rate_cb);
+err_disable_clk:
+	clk_disable_unprepare(clk);
+err_free:
+	kfree(ce);
+	return ret;
 }
 
 static void __init sun5i_timer_init(struct device_node *node)
 {
 	struct reset_control *rstc;
-	unsigned long rate;
+	void __iomem *timer_base;
 	struct clk *clk;
-	int ret, irq;
-	u32 val;
+	int irq;
 
-	timer_base = of_iomap(node, 0);
+	timer_base = of_io_request_and_map(node, 0, of_node_full_name(node));
 	if (!timer_base)
 		panic("Can't map registers");
 
@@ -161,36 +334,13 @@ static void __init sun5i_timer_init(struct device_node *node)
 	clk = of_clk_get(node, 0);
 	if (IS_ERR(clk))
 		panic("Can't get timer clock");
-	clk_prepare_enable(clk);
-	rate = clk_get_rate(clk);
 
 	rstc = of_reset_control_get(node, NULL);
 	if (!IS_ERR(rstc))
 		reset_control_deassert(rstc);
 
-	writel(~0, timer_base + TIMER_INTVAL_LO_REG(1));
-	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
-	       timer_base + TIMER_CTL_REG(1));
-
-	sched_clock_register(sun5i_timer_sched_read, 32, rate);
-	clocksource_mmio_init(timer_base + TIMER_CNTVAL_LO_REG(1), node->name,
-			      rate, 340, 32, clocksource_mmio_readl_down);
-
-	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
-
-	/* Enable timer0 interrupt */
-	val = readl(timer_base + TIMER_IRQ_EN_REG);
-	writel(val | TIMER_IRQ_EN(0), timer_base + TIMER_IRQ_EN_REG);
-
-	sun5i_clockevent.cpumask = cpu_possible_mask;
-	sun5i_clockevent.irq = irq;
-
-	clockevents_config_and_register(&sun5i_clockevent, rate,
-					TIMER_SYNC_TICKS, 0xffffffff);
-
-	ret = setup_irq(irq, &sun5i_timer_irq);
-	if (ret)
-		pr_warn("failed to setup irq %d\n", irq);
+	sun5i_setup_clocksource(node, timer_base, clk, irq);
+	sun5i_setup_clockevent(node, timer_base, clk, irq);
 }
 CLOCKSOURCE_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer",
 		       sun5i_timer_init);