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* [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes
@ 2015-01-11 11:40 Maxime Ripard
  2015-01-11 11:40 ` [PATCH 1/5] clocksource: sun5i: Switch to request_irq Maxime Ripard
                   ` (4 more replies)
  0 siblings, 5 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

Hi,

The Allwinner HS timers have the AHB clock as their parent
clock. Since this clock is shared with other devices, we could very
well have another driver requesting a rate change of that clock,
making our timer change frequency at the same time.

This is especially true on the A31, where the DMA controller needs to
do such a rate change, making the HS timer unreliable at the time on
the A31.

This serie makes some cleanups and implements clock notifiers to be
able to reflect such rate changes and make sure that the timer is
always working.

Maxime

Maxime Ripard (5):
  clocksource: sun5i: Switch to request_irq
  clocksource: sun5i: Use of_io_request_and_map
  clocksource: sun5i: Remove sched_clock
  clocksource: sun5i: Refactor the current code
  clocksource: sun5i: Add clock notifiers

 drivers/clocksource/timer-sun5i.c | 306 +++++++++++++++++++++++++++++---------
 1 file changed, 232 insertions(+), 74 deletions(-)

-- 
2.2.1


^ permalink raw reply	[flat|nested] 8+ messages in thread

* [PATCH 1/5] clocksource: sun5i: Switch to request_irq
  2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
@ 2015-01-11 11:40 ` Maxime Ripard
  2015-01-18 18:40   ` Daniel Lezcano
  2015-01-11 11:40 ` [PATCH 2/5] clocksource: sun5i: Use of_io_request_and_map Maxime Ripard
                   ` (3 subsequent siblings)
  4 siblings, 1 reply; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

The current code uses setup_irq, while it could perfectly use the much simpler
request_irq. Switch to that.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 drivers/clocksource/timer-sun5i.c | 10 ++--------
 1 file changed, 2 insertions(+), 8 deletions(-)

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 02268448dc85..738853873a3b 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -130,13 +130,6 @@ static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
 	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 u64 sun5i_timer_sched_read(void)
 {
 	return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
@@ -178,7 +171,8 @@ static void __init sun5i_timer_init(struct device_node *node)
 
 	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
 
-	ret = setup_irq(irq, &sun5i_timer_irq);
+	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			  "sun5i_timer", &sun5i_clockevent);
 	if (ret)
 		pr_warn("failed to setup irq %d\n", irq);
 
-- 
2.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 2/5] clocksource: sun5i: Use of_io_request_and_map
  2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
  2015-01-11 11:40 ` [PATCH 1/5] clocksource: sun5i: Switch to request_irq Maxime Ripard
@ 2015-01-11 11:40 ` Maxime Ripard
  2015-01-11 11:40 ` [PATCH 3/5] clocksource: sun5i: Remove sched_clock Maxime Ripard
                   ` (2 subsequent siblings)
  4 siblings, 0 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

of_iomap doesn't do a request_mem_region on the memory area defined in the DT
it maps. Switch to of_io_request_and_map to make sure we're the only users.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 drivers/clocksource/timer-sun5i.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 738853873a3b..ec82c4c69dfc 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -143,7 +143,8 @@ static void __init sun5i_timer_init(struct device_node *node)
 	int ret, irq;
 	u32 val;
 
-	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");
 
-- 
2.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 3/5] clocksource: sun5i: Remove sched_clock
  2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
  2015-01-11 11:40 ` [PATCH 1/5] clocksource: sun5i: Switch to request_irq Maxime Ripard
  2015-01-11 11:40 ` [PATCH 2/5] clocksource: sun5i: Use of_io_request_and_map Maxime Ripard
@ 2015-01-11 11:40 ` Maxime Ripard
  2015-01-11 11:40 ` [PATCH 4/5] clocksource: sun5i: Refactor the current code Maxime Ripard
  2015-01-11 11:40 ` [PATCH 5/5] clocksource: sun5i: Add clock notifiers Maxime Ripard
  4 siblings, 0 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

It's not possible to remove a sched_clock once it has been added, nor is it
possible to change its rate.

Since we will need to support a rate change, and that we have other
sched_clocks in the system anyway, remove it.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 drivers/clocksource/timer-sun5i.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index ec82c4c69dfc..3db470dd7a5b 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -130,11 +130,6 @@ static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static u64 sun5i_timer_sched_read(void)
-{
-	return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
-}
-
 static void __init sun5i_timer_init(struct device_node *node)
 {
 	struct reset_control *rstc;
@@ -166,7 +161,6 @@ static void __init sun5i_timer_init(struct device_node *node)
 	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);
 
-- 
2.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 4/5] clocksource: sun5i: Refactor the current code
  2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
                   ` (2 preceding siblings ...)
  2015-01-11 11:40 ` [PATCH 3/5] clocksource: sun5i: Remove sched_clock Maxime Ripard
@ 2015-01-11 11:40 ` Maxime Ripard
  2015-01-11 11:40 ` [PATCH 5/5] clocksource: sun5i: Add clock notifiers Maxime Ripard
  4 siblings, 0 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

Refactor the code in order to remove the global variables and split the clock
source and clock events registration in order to ease the addition of the clock
notifiers needed to handle the parent clock rate changes.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 drivers/clocksource/timer-sun5i.c | 231 +++++++++++++++++++++++++++-----------
 1 file changed, 166 insertions(+), 65 deletions(-)

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 3db470dd7a5b..384e3ab6145d 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -18,6 +18,7 @@
 #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 +38,27 @@
 
 #define TIMER_SYNC_TICKS	3
 
-static void __iomem *timer_base;
-static u32 ticks_per_jiffy;
+struct sun5i_timer {
+	void __iomem		*base;
+	struct clk		*clk;
+	u32			ticks_per_jiffy;
+};
+
+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 +66,30 @@ 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;
@@ -77,66 +97,170 @@ 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 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 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;
+
+	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_disable_clk;
+	}
+
+	return 0;
+
+err_disable_clk:
+	clk_disable_unprepare(clk);
+err_free:
+	kfree(cs);
+	return ret;
+}
+
+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->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);
+
+	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			  "sun5i_timer", ce);
+	if (ret) {
+		pr_err("Unable to register interrupt\n");
+		goto err_disable_clk;
+	}
+
+	clockevents_config_and_register(&ce->clkevt, rate,
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	return 0;
+
+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_io_request_and_map(node, 0,
 					   of_node_full_name(node));
@@ -150,36 +274,13 @@ 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));
-
-	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);
-
-	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
-			  "sun5i_timer", &sun5i_clockevent);
-	if (ret)
-		pr_warn("failed to setup irq %d\n", irq);
-
-	/* 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);
+	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);
-- 
2.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* [PATCH 5/5] clocksource: sun5i: Add clock notifiers
  2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
                   ` (3 preceding siblings ...)
  2015-01-11 11:40 ` [PATCH 4/5] clocksource: sun5i: Refactor the current code Maxime Ripard
@ 2015-01-11 11:40 ` Maxime Ripard
  4 siblings, 0 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-11 11:40 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Maxime Ripard

The parent clock of the sun5i timer is the AHB clock, which rate might change
because of other devices requirements.

This is for example the case on the Allwinner A31, where the DMA controller
needs a minimum rate higher than the default, that is enforced after the timer
driver has probed.

Add clock notifiers to make sure we reflect the clock rate changes in the timer
rates.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
---
 drivers/clocksource/timer-sun5i.c | 72 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 70 insertions(+), 2 deletions(-)

diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
index 384e3ab6145d..afb998d30aff 100644
--- a/drivers/clocksource/timer-sun5i.c
+++ b/drivers/clocksource/timer-sun5i.c
@@ -41,9 +41,13 @@
 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;
@@ -152,6 +156,30 @@ static cycle_t sun5i_clksrc_read(struct clocksource *clksrc)
 	return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1));
 }
 
+static int sun5i_rate_cb_clksrc(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_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)
@@ -174,6 +202,14 @@ static int __init sun5i_setup_clocksource(struct device_node *node,
 
 	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,
@@ -188,11 +224,13 @@ static int __init sun5i_setup_clocksource(struct device_node *node,
 	ret = clocksource_register_hz(&cs->clksrc, rate);
 	if (ret) {
 		pr_err("Couldn't register clock source.\n");
-		goto err_disable_clk;
+		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:
@@ -200,6 +238,26 @@ err_free:
 	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);
+	unsigned long flags;
+
+	if (event == POST_RATE_CHANGE) {
+		local_irq_save(flags);
+		clockevents_update_freq(&ce->clkevt, ndata->new_rate);
+		local_irq_restore(flags);
+
+		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)
 {
@@ -223,6 +281,14 @@ static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem
 	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;
@@ -240,7 +306,7 @@ static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem
 			  "sun5i_timer", ce);
 	if (ret) {
 		pr_err("Unable to register interrupt\n");
-		goto err_disable_clk;
+		goto err_remove_notifier;
 	}
 
 	clockevents_config_and_register(&ce->clkevt, rate,
@@ -248,6 +314,8 @@ static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem
 
 	return 0;
 
+err_remove_notifier:
+	clk_notifier_unregister(clk, &ce->timer.clk_rate_cb);
 err_disable_clk:
 	clk_disable_unprepare(clk);
 err_free:
-- 
2.2.1


^ permalink raw reply related	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/5] clocksource: sun5i: Switch to request_irq
  2015-01-11 11:40 ` [PATCH 1/5] clocksource: sun5i: Switch to request_irq Maxime Ripard
@ 2015-01-18 18:40   ` Daniel Lezcano
  2015-01-21  9:17     ` Maxime Ripard
  0 siblings, 1 reply; 8+ messages in thread
From: Daniel Lezcano @ 2015-01-18 18:40 UTC (permalink / raw)
  To: Maxime Ripard, Thomas Gleixner; +Cc: linux-kernel, linux-arm-kernel

On 01/11/2015 12:40 PM, Maxime Ripard wrote:
> The current code uses setup_irq, while it could perfectly use the much simpler
> request_irq. Switch to that.
>
> Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> ---
>   drivers/clocksource/timer-sun5i.c | 10 ++--------
>   1 file changed, 2 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
> index 02268448dc85..738853873a3b 100644
> --- a/drivers/clocksource/timer-sun5i.c
> +++ b/drivers/clocksource/timer-sun5i.c
> @@ -130,13 +130,6 @@ static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
>   	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 u64 sun5i_timer_sched_read(void)
>   {
>   	return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
> @@ -178,7 +171,8 @@ static void __init sun5i_timer_init(struct device_node *node)
>
>   	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
>
> -	ret = setup_irq(irq, &sun5i_timer_irq);
> +	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
> +			  "sun5i_timer", &sun5i_clockevent);

Is the timer name change done in purpose ?

>   	if (ret)
>   		pr_warn("failed to setup irq %d\n", irq);
>
>


-- 
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^ permalink raw reply	[flat|nested] 8+ messages in thread

* Re: [PATCH 1/5] clocksource: sun5i: Switch to request_irq
  2015-01-18 18:40   ` Daniel Lezcano
@ 2015-01-21  9:17     ` Maxime Ripard
  0 siblings, 0 replies; 8+ messages in thread
From: Maxime Ripard @ 2015-01-21  9:17 UTC (permalink / raw)
  To: Daniel Lezcano; +Cc: Thomas Gleixner, linux-kernel, linux-arm-kernel

[-- Attachment #1: Type: text/plain, Size: 1630 bytes --]

On Sun, Jan 18, 2015 at 07:40:56PM +0100, Daniel Lezcano wrote:
> On 01/11/2015 12:40 PM, Maxime Ripard wrote:
> >The current code uses setup_irq, while it could perfectly use the much simpler
> >request_irq. Switch to that.
> >
> >Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
> >---
> >  drivers/clocksource/timer-sun5i.c | 10 ++--------
> >  1 file changed, 2 insertions(+), 8 deletions(-)
> >
> >diff --git a/drivers/clocksource/timer-sun5i.c b/drivers/clocksource/timer-sun5i.c
> >index 02268448dc85..738853873a3b 100644
> >--- a/drivers/clocksource/timer-sun5i.c
> >+++ b/drivers/clocksource/timer-sun5i.c
> >@@ -130,13 +130,6 @@ static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
> >  	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 u64 sun5i_timer_sched_read(void)
> >  {
> >  	return ~readl(timer_base + TIMER_CNTVAL_LO_REG(1));
> >@@ -178,7 +171,8 @@ static void __init sun5i_timer_init(struct device_node *node)
> >
> >  	ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
> >
> >-	ret = setup_irq(irq, &sun5i_timer_irq);
> >+	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
> >+			  "sun5i_timer", &sun5i_clockevent);
> 
> Is the timer name change done in purpose ?

Hmm, no, it's a mistake. I'll resend a v2.

Maxime

-- 
Maxime Ripard, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

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^ permalink raw reply	[flat|nested] 8+ messages in thread

end of thread, other threads:[~2015-01-21  9:20 UTC | newest]

Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-11 11:40 [PATCH 0/5] clocksource: sun5i: Support parent clock rate changes Maxime Ripard
2015-01-11 11:40 ` [PATCH 1/5] clocksource: sun5i: Switch to request_irq Maxime Ripard
2015-01-18 18:40   ` Daniel Lezcano
2015-01-21  9:17     ` Maxime Ripard
2015-01-11 11:40 ` [PATCH 2/5] clocksource: sun5i: Use of_io_request_and_map Maxime Ripard
2015-01-11 11:40 ` [PATCH 3/5] clocksource: sun5i: Remove sched_clock Maxime Ripard
2015-01-11 11:40 ` [PATCH 4/5] clocksource: sun5i: Refactor the current code Maxime Ripard
2015-01-11 11:40 ` [PATCH 5/5] clocksource: sun5i: Add clock notifiers Maxime Ripard

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