[PULL] : clockevents for 4.4

[PULL] : clockevents for 4.4

[Daniel Lezcano]

Hi Thomas,

this pull request has the following contents:

  - Removed unneeded memset in em_sti, sh_cmt and h8300 because there 
are already zeroed by a kzalloc (Alexey Klimov)

  - Optimized code by replacing this_cpu_ptr by container_of on the 
exynos_mct (Alexey Klimov)

  - Got immune from a spurious interrupt when enabling the mtk_timer 
(Daniel Lezcano)

  - Used the dynamic irq affinity to optimize wakeup and useless IPI 
timer on the imx timer (Lucas Stach)

  - Added new timer for Tango SoCs (Marc Gonzalez)

  - Implemented the timer delay for armada-370-xp (Russell King)

  - Used GPT as clock source (Yingjoe Chen)

Thanks !

   -- Daniel

The following changes since commit c8d75aa47dd585c9538a8205e9bb9847e12cfb84:

   posix_cpu_timer: Reduce unnecessary sighand lock contention 
(2015-10-15 11:23:41 +0200)

are available in the git repository at:

   http://git.linaro.org/people/daniel.lezcano/linux.git clockevents/4.4

for you to fetch changes up to cb0f2538039c65f2bb64a9d427dbe9dd7d0f71a6:

   clocksource/drivers/armada-370-xp: Implement ARM delay timer 
(2015-10-19 22:42:14 +0200)

----------------------------------------------------------------
Alexey Klimov (4):
       clocksource/drivers/em_sti: Remove unneeded memset()s
       clocksource/drivers/sh_cmt: Remove unneeded memset() in 
sh_cmt_setup()
       clocksource/drivers/h8300_*: Remove unneeded memset()s
       clocksource/drivers/exynos_mct: Use container_of() instead of 
this_cpu_ptr()

Daniel Lezcano (1):
       clockevents/drivers/mtk: Fix spurious interrupt leading to crash

Lucas Stach (1):
       clocksource/drivers/imx: Allow timer irq affinity change

Marc Gonzalez (1):
       clocksource/drivers/tango_xtal: Add new timer for Tango SoCs

Russell King (1):
       clocksource/drivers/armada-370-xp: Implement ARM delay timer

Yingjoe Chen (1):
       clocksource/drivers/mediatek: Use GPT as sched clock source

  drivers/clocksource/Kconfig              |  4 ++
  drivers/clocksource/Makefile             |  1 +
  drivers/clocksource/em_sti.c             |  2 -
  drivers/clocksource/exynos_mct.c         | 12 ++++--
  drivers/clocksource/h8300_timer16.c      |  1 -
  drivers/clocksource/h8300_timer8.c       |  1 -
  drivers/clocksource/h8300_tpu.c          |  1 -
  drivers/clocksource/mtk_timer.c          | 26 ++++++++-----
  drivers/clocksource/sh_cmt.c             |  1 -
  drivers/clocksource/tango_xtal.c         | 66 
++++++++++++++++++++++++++++++++
  drivers/clocksource/time-armada-370-xp.c | 14 +++++++
  drivers/clocksource/timer-imx-gpt.c      |  3 +-
  12 files changed, 111 insertions(+), 21 deletions(-)
  create mode 100644 drivers/clocksource/tango_xtal.c
-- 
  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

Follow Linaro:  <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
<http://www.linaro.org/linaro-blog/> Blog

[PATCH 1/9] clockevents/drivers/mtk: Fix spurious interrupt leading to crash

[Daniel Lezcano]

After analysis done by Yingjoe Chen, the timer appears to have a pending
interrupt when it is enabled.

Fix this by acknowledging the pending interrupt when enabling the timer
interrupt.

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
---
 drivers/clocksource/mtk_timer.c | 16 ++++++----------
 1 file changed, 6 insertions(+), 10 deletions(-)

diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
index 50f0641..c8badc4 100644
--- a/drivers/clocksource/mtk_timer.c
+++ b/drivers/clocksource/mtk_timer.c
@@ -141,14 +141,6 @@ static irqreturn_t mtk_timer_interrupt(int irq, void *dev_id)
 	return IRQ_HANDLED;
 }
 
-static void mtk_timer_global_reset(struct mtk_clock_event_device *evt)
-{
-	/* Disable all interrupts */
-	writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG);
-	/* Acknowledge all interrupts */
-	writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
-}
-
 static void
 mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
 {
@@ -168,6 +160,12 @@ static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer)
 {
 	u32 val;
 
+	/* Disable all interrupts */
+	writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG);
+
+	/* Acknowledge all spurious pending interrupts */
+	writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
+
 	val = readl(evt->gpt_base + GPT_IRQ_EN_REG);
 	writel(val | GPT_IRQ_ENABLE(timer),
 			evt->gpt_base + GPT_IRQ_EN_REG);
@@ -220,8 +218,6 @@ static void __init mtk_timer_init(struct device_node *node)
 	}
 	rate = clk_get_rate(clk);
 
-	mtk_timer_global_reset(evt);
-
 	if (request_irq(evt->dev.irq, mtk_timer_interrupt,
 			IRQF_TIMER | IRQF_IRQPOLL, "mtk_timer", evt)) {
 		pr_warn("failed to setup irq %d\n", evt->dev.irq);
-- 
1.9.1

[PATCH 2/9] clocksource/drivers/mediatek: Use GPT as sched clock source

[Daniel Lezcano]

From: Yingjoe Chen <yingjoe.chen@mediatek.com>

When cpu is in deep idle, arch timer will stop counting. Setup GPT as
sched clock source so it can keep counting in idle.

Signed-off-by: Yingjoe Chen <yingjoe.chen@mediatek.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>
---
 drivers/clocksource/mtk_timer.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
index c8badc4..fbfc746 100644
--- a/drivers/clocksource/mtk_timer.c
+++ b/drivers/clocksource/mtk_timer.c
@@ -24,6 +24,7 @@
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
+#include <linux/sched_clock.h>
 #include <linux/slab.h>
 
 #define GPT_IRQ_EN_REG		0x00
@@ -59,6 +60,13 @@ struct mtk_clock_event_device {
 	struct clock_event_device dev;
 };
 
+static void __iomem *gpt_sched_reg __read_mostly;
+
+static u64 notrace mtk_read_sched_clock(void)
+{
+	return readl_relaxed(gpt_sched_reg);
+}
+
 static inline struct mtk_clock_event_device *to_mtk_clk(
 				struct clock_event_device *c)
 {
@@ -230,6 +238,8 @@ static void __init mtk_timer_init(struct device_node *node)
 	mtk_timer_setup(evt, GPT_CLK_SRC, TIMER_CTRL_OP_FREERUN);
 	clocksource_mmio_init(evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC),
 			node->name, rate, 300, 32, clocksource_mmio_readl_up);
+	gpt_sched_reg = evt->gpt_base + TIMER_CNT_REG(GPT_CLK_SRC);
+	sched_clock_register(mtk_read_sched_clock, 32, rate);
 
 	/* Configure clock event */
 	mtk_timer_setup(evt, GPT_CLK_EVT, TIMER_CTRL_OP_REPEAT);
-- 
1.9.1

[PATCH 3/9] clocksource/drivers/em_sti: Remove unneeded memset()s

[Daniel Lezcano]

From: Alexey Klimov <alexey.klimov@linaro.org>

Memory for cs and ced fields in struct em_sti_priv is allocated
by devm_kzalloc() in the beginning of em_sti_probe() so they
don't need to be zeroed one more time in
em_sti_register_clocksource() and in em_sti_register_clockevent().

Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/em_sti.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/drivers/clocksource/em_sti.c b/drivers/clocksource/em_sti.c
index 7a97a34..19bb179 100644
--- a/drivers/clocksource/em_sti.c
+++ b/drivers/clocksource/em_sti.c
@@ -228,7 +228,6 @@ static int em_sti_register_clocksource(struct em_sti_priv *p)
 {
 	struct clocksource *cs = &p->cs;
 
-	memset(cs, 0, sizeof(*cs));
 	cs->name = dev_name(&p->pdev->dev);
 	cs->rating = 200;
 	cs->read = em_sti_clocksource_read;
@@ -285,7 +284,6 @@ static void em_sti_register_clockevent(struct em_sti_priv *p)
 {
 	struct clock_event_device *ced = &p->ced;
 
-	memset(ced, 0, sizeof(*ced));
 	ced->name = dev_name(&p->pdev->dev);
 	ced->features = CLOCK_EVT_FEAT_ONESHOT;
 	ced->rating = 200;
-- 
1.9.1

[PATCH 4/9] clocksource/drivers/sh_cmt: Remove unneeded memset() in sh_cmt_setup()

[Daniel Lezcano]

From: Alexey Klimov <alexey.klimov@linaro.org>

Memory for cmt struct is allocated by kzalloc() in sh_cmt_setup.

Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/sh_cmt.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/drivers/clocksource/sh_cmt.c b/drivers/clocksource/sh_cmt.c
index ba73a6e..103c493 100644
--- a/drivers/clocksource/sh_cmt.c
+++ b/drivers/clocksource/sh_cmt.c
@@ -962,7 +962,6 @@ static int sh_cmt_setup(struct sh_cmt_device *cmt, struct platform_device *pdev)
 	unsigned int i;
 	int ret;
 
-	memset(cmt, 0, sizeof(*cmt));
 	cmt->pdev = pdev;
 	raw_spin_lock_init(&cmt->lock);
 
-- 
1.9.1

[PATCH 5/9] clocksource/drivers/h8300_*: Remove unneeded memset()s

[Daniel Lezcano]

From: Alexey Klimov <alexey.klimov@linaro.org>

Memory for timer16_priv, timer8_priv and tpu_priv structs is
allocated by devm_kzalloc() in corresponding probe functions
of drivers.
No need to zero it one more time.

Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/h8300_timer16.c | 1 -
 drivers/clocksource/h8300_timer8.c  | 1 -
 drivers/clocksource/h8300_tpu.c     | 1 -
 3 files changed, 3 deletions(-)

diff --git a/drivers/clocksource/h8300_timer16.c b/drivers/clocksource/h8300_timer16.c
index 82941c1..0e076c6 100644
--- a/drivers/clocksource/h8300_timer16.c
+++ b/drivers/clocksource/h8300_timer16.c
@@ -153,7 +153,6 @@ static int timer16_setup(struct timer16_priv *p, struct platform_device *pdev)
 	int ret, irq;
 	unsigned int ch;
 
-	memset(p, 0, sizeof(*p));
 	p->pdev = pdev;
 
 	res[REG_CH] = platform_get_resource(p->pdev,
diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c
index f9b3b70..44375d8 100644
--- a/drivers/clocksource/h8300_timer8.c
+++ b/drivers/clocksource/h8300_timer8.c
@@ -215,7 +215,6 @@ static int timer8_setup(struct timer8_priv *p,
 	int irq;
 	int ret;
 
-	memset(p, 0, sizeof(*p));
 	p->pdev = pdev;
 
 	res = platform_get_resource(p->pdev, IORESOURCE_MEM, 0);
diff --git a/drivers/clocksource/h8300_tpu.c b/drivers/clocksource/h8300_tpu.c
index 64195fd..5487410 100644
--- a/drivers/clocksource/h8300_tpu.c
+++ b/drivers/clocksource/h8300_tpu.c
@@ -123,7 +123,6 @@ static int __init tpu_setup(struct tpu_priv *p, struct platform_device *pdev)
 {
 	struct resource *res[2];
 
-	memset(p, 0, sizeof(*p));
 	p->pdev = pdev;
 
 	res[CH_L] = platform_get_resource(p->pdev, IORESOURCE_MEM, CH_L);
-- 
1.9.1

Re: [PATCH 5/9] clocksource/drivers/h8300_*: Remove unneeded memset()s

[Yoshinori Sato]

On Tue, 20 Oct 2015 05:59:24 +0900,
Daniel Lezcano wrote:
> 
> From: Alexey Klimov <alexey.klimov@linaro.org>
> 
> Memory for timer16_priv, timer8_priv and tpu_priv structs is
> allocated by devm_kzalloc() in corresponding probe functions
> of drivers.
> No need to zero it one more time.
> 
> Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Acked-by: Yoshinori Sato <ysato@users.sourceforge.jp>

> ---
>  drivers/clocksource/h8300_timer16.c | 1 -
>  drivers/clocksource/h8300_timer8.c  | 1 -
>  drivers/clocksource/h8300_tpu.c     | 1 -
>  3 files changed, 3 deletions(-)
> 
> diff --git a/drivers/clocksource/h8300_timer16.c b/drivers/clocksource/h8300_timer16.c
> index 82941c1..0e076c6 100644
> --- a/drivers/clocksource/h8300_timer16.c
> +++ b/drivers/clocksource/h8300_timer16.c
> @@ -153,7 +153,6 @@ static int timer16_setup(struct timer16_priv *p, struct platform_device *pdev)
>  	int ret, irq;
>  	unsigned int ch;
>  
> -	memset(p, 0, sizeof(*p));
>  	p->pdev = pdev;
>  
>  	res[REG_CH] = platform_get_resource(p->pdev,
> diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c
> index f9b3b70..44375d8 100644
> --- a/drivers/clocksource/h8300_timer8.c
> +++ b/drivers/clocksource/h8300_timer8.c
> @@ -215,7 +215,6 @@ static int timer8_setup(struct timer8_priv *p,
>  	int irq;
>  	int ret;
>  
> -	memset(p, 0, sizeof(*p));
>  	p->pdev = pdev;
>  
>  	res = platform_get_resource(p->pdev, IORESOURCE_MEM, 0);
> diff --git a/drivers/clocksource/h8300_tpu.c b/drivers/clocksource/h8300_tpu.c
> index 64195fd..5487410 100644
> --- a/drivers/clocksource/h8300_tpu.c
> +++ b/drivers/clocksource/h8300_tpu.c
> @@ -123,7 +123,6 @@ static int __init tpu_setup(struct tpu_priv *p, struct platform_device *pdev)
>  {
>  	struct resource *res[2];
>  
> -	memset(p, 0, sizeof(*p));
>  	p->pdev = pdev;
>  
>  	res[CH_L] = platform_get_resource(p->pdev, IORESOURCE_MEM, CH_L);
> -- 
> 1.9.1
> 

[PATCH 6/9] clocksource/drivers/exynos_mct: Use container_of() instead of this_cpu_ptr()

[Daniel Lezcano]

From: Alexey Klimov <alexey.klimov@linaro.org>

Since evt structure is embedded in per-CPU mevt structure it's
definitely faster to use container_of() to get access to mevt
if we have evt (for example as incoming function argument) instead
of more expensive approach with this_cpu_ptr(&percpu_mct_tick).
this_cpu_ptr() on per-CPU mevt structure leads to access to cp15
to get cpu id and arithmetic operations.
Container_of() is cheaper since it's just one asm instruction.
This should work if used evt pointer is correct and owned by
local mevt structure.

For example, before this patch set_state_shutdown() looks like:

 4a4:	e92d4010 	push	{r4, lr}
 4a8:	e3004000 	movw	r4, #0
 4ac:	ebfffffe 	bl	0 <debug_smp_processor_id>
 4b0:	e3003000 	movw	r3, #0
 4b4:	e3404000 	movt	r4, #0
 4b8:	e3403000 	movt	r3, #0
 4bc:	e7933100 	ldr	r3, [r3, r0, lsl #2]
 4c0:	e0844003 	add	r4, r4, r3
 4c4:	e59400c0 	ldr	r0, [r4, #192]	; 0xc0
 4c8:	ebffffd4 	bl	420 <exynos4_mct_tick_stop.isra.1>
 4cc:	e3a00000 	mov	r0, #0
 4d0:	e8bd8010 	pop	{r4, pc}

With this patch:

 4a4:	e92d4010 	push	{r4, lr}
 4a8:	e59000c0 	ldr	r0, [r0, #192]	; 0xc0
 4ac:	ebffffdb 	bl	420 <exynos4_mct_tick_stop.isra.1>
 4b0:	e3a00000 	mov	r0, #0
 4b4:	e8bd8010 	pop	{r4, pc}

Also, for me size of exynos_mct.o decreased from 84588 bytes
to 83956.

Signed-off-by: Alexey Klimov <alexey.klimov@linaro.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Reviewed-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
---
 drivers/clocksource/exynos_mct.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/drivers/clocksource/exynos_mct.c b/drivers/clocksource/exynos_mct.c
index 029f96a..ff44082 100644
--- a/drivers/clocksource/exynos_mct.c
+++ b/drivers/clocksource/exynos_mct.c
@@ -382,24 +382,28 @@ static void exynos4_mct_tick_start(unsigned long cycles,
 static int exynos4_tick_set_next_event(unsigned long cycles,
 				       struct clock_event_device *evt)
 {
-	struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
+	struct mct_clock_event_device *mevt;
 
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
 	exynos4_mct_tick_start(cycles, mevt);
-
 	return 0;
 }
 
 static int set_state_shutdown(struct clock_event_device *evt)
 {
-	exynos4_mct_tick_stop(this_cpu_ptr(&percpu_mct_tick));
+	struct mct_clock_event_device *mevt;
+
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
+	exynos4_mct_tick_stop(mevt);
 	return 0;
 }
 
 static int set_state_periodic(struct clock_event_device *evt)
 {
-	struct mct_clock_event_device *mevt = this_cpu_ptr(&percpu_mct_tick);
+	struct mct_clock_event_device *mevt;
 	unsigned long cycles_per_jiffy;
 
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
 	cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
 			    >> evt->shift);
 	exynos4_mct_tick_stop(mevt);
-- 
1.9.1

[PATCH 7/9] clocksource/drivers/imx: Allow timer irq affinity change

[Daniel Lezcano]

From: Lucas Stach <l.stach@pengutronix.de>

Allow the timer core to change the smp affinity of the broadcast timer
irq by setting CLOCK_EVT_FEAT_DYNIRQ flag. For this to work the timer
core needs to be told about the used irq.

This reduces interrupt pressure and wakeups on CPU0 as well as vastly
reducing the number of timer broadcast IPIs.

Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/timer-imx-gpt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-imx-gpt.c b/drivers/clocksource/timer-imx-gpt.c
index 839aba9..99ec967 100644
--- a/drivers/clocksource/timer-imx-gpt.c
+++ b/drivers/clocksource/timer-imx-gpt.c
@@ -305,13 +305,14 @@ static int __init mxc_clockevent_init(struct imx_timer *imxtm)
 	struct irqaction *act = &imxtm->act;
 
 	ced->name = "mxc_timer1";
-	ced->features = CLOCK_EVT_FEAT_ONESHOT;
+	ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
 	ced->set_state_shutdown = mxc_shutdown;
 	ced->set_state_oneshot = mxc_set_oneshot;
 	ced->tick_resume = mxc_shutdown;
 	ced->set_next_event = imxtm->gpt->set_next_event;
 	ced->rating = 200;
 	ced->cpumask = cpumask_of(0);
+	ced->irq = imxtm->irq;
 	clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per),
 					0xff, 0xfffffffe);
 
-- 
1.9.1

[PATCH 8/9] clocksource/drivers/tango_xtal: Add new timer for Tango SoCs

[Daniel Lezcano]

From: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>

Sigma Designs Tango platforms provide a 27 MHz crystal oscillator.
Use it for clocksource, sched_clock, and delay_timer.

Signed-off-by: Marc Gonzalez <marc_gonzalez@sigmadesigns.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
---
 drivers/clocksource/Kconfig      |  4 +++
 drivers/clocksource/Makefile     |  1 +
 drivers/clocksource/tango_xtal.c | 66 ++++++++++++++++++++++++++++++++++++++++
 3 files changed, 71 insertions(+)
 create mode 100644 drivers/clocksource/tango_xtal.c

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index a7726db..50b68bc 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -279,6 +279,10 @@ config CLKSRC_MIPS_GIC
 	depends on MIPS_GIC
 	select CLKSRC_OF
 
+config CLKSRC_TANGO_XTAL
+	bool
+	select CLKSRC_OF
+
 config CLKSRC_PXA
 	def_bool y if ARCH_PXA || ARCH_SA1100
 	select CLKSRC_OF if OF
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 5c00863..fc9348d 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -56,6 +56,7 @@ obj-$(CONFIG_ARCH_KEYSTONE)		+= timer-keystone.o
 obj-$(CONFIG_ARCH_INTEGRATOR_AP)	+= timer-integrator-ap.o
 obj-$(CONFIG_CLKSRC_VERSATILE)		+= versatile.o
 obj-$(CONFIG_CLKSRC_MIPS_GIC)		+= mips-gic-timer.o
+obj-$(CONFIG_CLKSRC_TANGO_XTAL)		+= tango_xtal.o
 obj-$(CONFIG_CLKSRC_IMX_GPT)		+= timer-imx-gpt.o
 obj-$(CONFIG_ASM9260_TIMER)		+= asm9260_timer.o
 obj-$(CONFIG_H8300)			+= h8300_timer8.o
diff --git a/drivers/clocksource/tango_xtal.c b/drivers/clocksource/tango_xtal.c
new file mode 100644
index 0000000..d297b30
--- /dev/null
+++ b/drivers/clocksource/tango_xtal.c
@@ -0,0 +1,66 @@
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+#include <linux/of_address.h>
+#include <linux/printk.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+
+static void __iomem *xtal_in_cnt;
+static struct delay_timer delay_timer;
+
+static unsigned long notrace read_xtal_counter(void)
+{
+	return readl_relaxed(xtal_in_cnt);
+}
+
+static u64 notrace read_sched_clock(void)
+{
+	return read_xtal_counter();
+}
+
+static cycle_t read_clocksource(struct clocksource *cs)
+{
+	return read_xtal_counter();
+}
+
+static struct clocksource tango_xtal = {
+	.name	= "tango-xtal",
+	.rating	= 350,
+	.read	= read_clocksource,
+	.mask	= CLOCKSOURCE_MASK(32),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void __init tango_clocksource_init(struct device_node *np)
+{
+	struct clk *clk;
+	int xtal_freq, ret;
+
+	xtal_in_cnt = of_iomap(np, 0);
+	if (xtal_in_cnt == NULL) {
+		pr_err("%s: invalid address\n", np->full_name);
+		return;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("%s: invalid clock\n", np->full_name);
+		return;
+	}
+
+	xtal_freq = clk_get_rate(clk);
+	delay_timer.freq = xtal_freq;
+	delay_timer.read_current_timer = read_xtal_counter;
+
+	ret = clocksource_register_hz(&tango_xtal, xtal_freq);
+	if (ret != 0) {
+		pr_err("%s: registration failed\n", np->full_name);
+		return;
+	}
+
+	sched_clock_register(read_sched_clock, 32, xtal_freq);
+	register_current_timer_delay(&delay_timer);
+}
+
+CLOCKSOURCE_OF_DECLARE(tango, "sigma,tick-counter", tango_clocksource_init);
-- 
1.9.1

[PATCH 9/9] clocksource/drivers/armada-370-xp: Implement ARM delay timer

[Daniel Lezcano]

From: Russell King <rmk+kernel@arm.linux.org.uk>

Implement an ARM delay timer to be used for udelay() on Armada 37x
platforms.  This allows us to skip the delay loop calibration at boot,
saving 180ms on the boot time of the kernel (which is around 10%).

It also means that udelay() will be unaffected by CPU frequency changes
when cpufreq is enabled on these platforms.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Acked-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
---
 drivers/clocksource/time-armada-370-xp.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/drivers/clocksource/time-armada-370-xp.c b/drivers/clocksource/time-armada-370-xp.c
index 2162796..d93ec3c 100644
--- a/drivers/clocksource/time-armada-370-xp.c
+++ b/drivers/clocksource/time-armada-370-xp.c
@@ -45,6 +45,8 @@
 #include <linux/percpu.h>
 #include <linux/syscore_ops.h>
 
+#include <asm/delay.h>
+
 /*
  * Timer block registers.
  */
@@ -249,6 +251,15 @@ struct syscore_ops armada_370_xp_timer_syscore_ops = {
 	.resume		= armada_370_xp_timer_resume,
 };
 
+static unsigned long armada_370_delay_timer_read(void)
+{
+	return ~readl(timer_base + TIMER0_VAL_OFF);
+}
+
+static struct delay_timer armada_370_delay_timer = {
+	.read_current_timer = armada_370_delay_timer_read,
+};
+
 static void __init armada_370_xp_timer_common_init(struct device_node *np)
 {
 	u32 clr = 0, set = 0;
@@ -287,6 +298,9 @@ static void __init armada_370_xp_timer_common_init(struct device_node *np)
 		TIMER0_RELOAD_EN | enable_mask,
 		TIMER0_RELOAD_EN | enable_mask);
 
+	armada_370_delay_timer.freq = timer_clk;
+	register_current_timer_delay(&armada_370_delay_timer);
+
 	/*
 	 * Set scale and timer for sched_clock.
 	 */
-- 
1.9.1

Re: [PATCH 1/9] clockevents/drivers/mtk: Fix spurious interrupt leading to crash

[Matthias Brugger]

2015-10-19 22:59 GMT+02:00 Daniel Lezcano <daniel.lezcano@linaro.org>:
> After analysis done by Yingjoe Chen, the timer appears to have a pending
> interrupt when it is enabled.
>
> Fix this by acknowledging the pending interrupt when enabling the timer
> interrupt.
>
> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
> Tested-by: Yingjoe Chen <yingjoe.chen@mediatek.com>

Acked-by: Matthias Brugger <matthias.bgg@gmail.com>

> ---
>  drivers/clocksource/mtk_timer.c | 16 ++++++----------
>  1 file changed, 6 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/clocksource/mtk_timer.c b/drivers/clocksource/mtk_timer.c
> index 50f0641..c8badc4 100644
> --- a/drivers/clocksource/mtk_timer.c
> +++ b/drivers/clocksource/mtk_timer.c
> @@ -141,14 +141,6 @@ static irqreturn_t mtk_timer_interrupt(int irq, void *dev_id)
>         return IRQ_HANDLED;
>  }
>
> -static void mtk_timer_global_reset(struct mtk_clock_event_device *evt)
> -{
> -       /* Disable all interrupts */
> -       writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG);
> -       /* Acknowledge all interrupts */
> -       writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
> -}
> -
>  static void
>  mtk_timer_setup(struct mtk_clock_event_device *evt, u8 timer, u8 option)
>  {
> @@ -168,6 +160,12 @@ static void mtk_timer_enable_irq(struct mtk_clock_event_device *evt, u8 timer)
>  {
>         u32 val;
>
> +       /* Disable all interrupts */
> +       writel(0x0, evt->gpt_base + GPT_IRQ_EN_REG);
> +
> +       /* Acknowledge all spurious pending interrupts */
> +       writel(0x3f, evt->gpt_base + GPT_IRQ_ACK_REG);
> +
>         val = readl(evt->gpt_base + GPT_IRQ_EN_REG);
>         writel(val | GPT_IRQ_ENABLE(timer),
>                         evt->gpt_base + GPT_IRQ_EN_REG);
> @@ -220,8 +218,6 @@ static void __init mtk_timer_init(struct device_node *node)
>         }
>         rate = clk_get_rate(clk);
>
> -       mtk_timer_global_reset(evt);
> -
>         if (request_irq(evt->dev.irq, mtk_timer_interrupt,
>                         IRQF_TIMER | IRQF_IRQPOLL, "mtk_timer", evt)) {
>                 pr_warn("failed to setup irq %d\n", evt->dev.irq);
> --
> 1.9.1
>



-- 
motzblog.wordpress.com