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* [PATCH v4 0/2] clocksource: Conexant CX92755 timers support
@ 2015-01-26  7:56 Baruch Siach
  2015-01-26  7:56 ` [PATCH v4 1/2] clocksource: devicetree: document Conexant Digicolor timer binding Baruch Siach
  2015-01-26  7:56 ` [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer Baruch Siach
  0 siblings, 2 replies; 7+ messages in thread
From: Baruch Siach @ 2015-01-26  7:56 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Baruch Siach

This short series adds support for the Conexant CX92755 SoC timers. This SoC is
part of the Conexant Digicolor series of SoCs.

v4:
   Address review comments by Daniel Lezcano:

   * Use macros for register configuration values

   * Encapsulate static objects in a struct

   * Use of_io_request_and_map to exclusively map registers

   * Use UINT_MAX instead of ~0

   * Use request_irq instead of setup_irq, obviating the need for a separate 
     irqaction struct

v3:
   http://article.gmane.org/gmane.linux.kernel/1870628
   http://article.gmane.org/gmane.linux.kernel/1870627

   * Split into a separate clocksource series

v2:
   http://article.gmane.org/gmane.linux.kernel/1861850
   http://article.gmane.org/gmane.linux.kernel/1861853

   * Change the timer dt binding, so that the 'reg' property points to the
     first "Agent Communication" register. This should improve the chance of
     reusing this binding for other SoCs in this series.

   * Add the CONTROL() and COUNT() macros to the timer driver to make the code
     clearer.

   * Move arch/arm Kconfig changes from the clocksource driver patch to the
     base arch support patch to reduce dependency between them

v1:
   http://article.gmane.org/gmane.linux.kernel/1855028
   http://article.gmane.org/gmane.linux.kernel/1855025

Baruch Siach (2):
  clocksource: devicetree: document Conexant Digicolor timer binding
  clocksource: driver for Conexant Digicolor SoC timer

 .../devicetree/bindings/timer/digicolor-timer.txt  |  18 +++
 drivers/clocksource/Makefile                       |   1 +
 drivers/clocksource/timer-digicolor.c              | 170 +++++++++++++++++++++
 3 files changed, 189 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/digicolor-timer.txt
 create mode 100644 drivers/clocksource/timer-digicolor.c

-- 
2.1.4


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v4 1/2] clocksource: devicetree: document Conexant Digicolor timer binding
  2015-01-26  7:56 [PATCH v4 0/2] clocksource: Conexant CX92755 timers support Baruch Siach
@ 2015-01-26  7:56 ` Baruch Siach
  2015-01-26  7:56 ` [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer Baruch Siach
  1 sibling, 0 replies; 7+ messages in thread
From: Baruch Siach @ 2015-01-26  7:56 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Baruch Siach

The Conexant CX92755 SoC provides 8 32-bit timers as part of its so called
"Agent Communication" block. Timers can be configures either as free running or
one shot. Each timer has a dedicated interrupt source in the CX92755 interrupts
controller. The first timer (Timer A) can also be configured as watchdog.

This commit adds devicetree binding definition of this hardware module. The
binding defined here should be reusable for other SoCs in the Digicolor series.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
 .../devicetree/bindings/timer/digicolor-timer.txt      | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/timer/digicolor-timer.txt

diff --git a/Documentation/devicetree/bindings/timer/digicolor-timer.txt b/Documentation/devicetree/bindings/timer/digicolor-timer.txt
new file mode 100644
index 000000000000..d1b659bbc29f
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/digicolor-timer.txt
@@ -0,0 +1,18 @@
+Conexant Digicolor SoCs Timer Controller
+
+Required properties:
+
+- compatible : should be "cnxt,cx92755-timer"
+- reg : Specifies base physical address and size of the "Agent Communication"
+  timer registers
+- interrupts : Contains 8 interrupts, one for each timer
+- clocks: phandle to the main clock
+
+Example:
+
+	timer@f0000fc0 {
+		compatible = "cnxt,cx92755-timer";
+		reg = <0xf0000fc0 0x40>;
+		interrupts = <19>, <31>, <34>, <35>, <52>, <53>, <54>, <55>;
+		clocks = <&main_clk>;
+	};
-- 
2.1.4


^ permalink raw reply	[flat|nested] 7+ messages in thread

* [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer
  2015-01-26  7:56 [PATCH v4 0/2] clocksource: Conexant CX92755 timers support Baruch Siach
  2015-01-26  7:56 ` [PATCH v4 1/2] clocksource: devicetree: document Conexant Digicolor timer binding Baruch Siach
@ 2015-01-26  7:56 ` Baruch Siach
  2015-01-26  9:43   ` Daniel Lezcano
  1 sibling, 1 reply; 7+ messages in thread
From: Baruch Siach @ 2015-01-26  7:56 UTC (permalink / raw)
  To: Daniel Lezcano, Thomas Gleixner
  Cc: linux-kernel, linux-arm-kernel, Baruch Siach

Add clocksource driver to the Conexant CX92755 SoC, part of the Digicolor SoCs
series. Hardware provides 8 timers, A to H. Timer A is dedicated to a future
watchdog driver so we don't use it here. Use timer B for sched_clock, and timer
C for clock_event.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
---
 drivers/clocksource/Makefile          |   1 +
 drivers/clocksource/timer-digicolor.c | 170 ++++++++++++++++++++++++++++++++++
 2 files changed, 171 insertions(+)
 create mode 100644 drivers/clocksource/timer-digicolor.c

diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 94d90b24b56b..a993c108be67 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_SH_TIMER_TMU)	+= sh_tmu.o
 obj-$(CONFIG_EM_TIMER_STI)	+= em_sti.o
 obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
 obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
+obj-$(CONFIG_ARCH_DIGICOLOR)	+= timer-digicolor.o
 obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
 obj-$(CONFIG_DW_APB_TIMER_OF)	+= dw_apb_timer_of.o
 obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
diff --git a/drivers/clocksource/timer-digicolor.c b/drivers/clocksource/timer-digicolor.c
new file mode 100644
index 000000000000..c97ea7eac4a5
--- /dev/null
+++ b/drivers/clocksource/timer-digicolor.c
@@ -0,0 +1,170 @@
+/*
+ * Conexant Digicolor timer driver
+ *
+ * Author: Baruch Siach <baruch@tkos.co.il>
+ *
+ * Copyright (C) 2014 Paradox Innovation Ltd.
+ *
+ * Based on:
+ *	Allwinner SoCs hstimer driver
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+/*
+ * Conexant Digicolor SoCs have 8 configurable timers, named from "Timer A" to
+ * "Timer H". Timer A is the only one with watchdog support, so it is dedicated
+ * to the watchdog driver. This driver uses Timer B for sched_clock(), and
+ * Timer C for clockevents.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+enum {
+	TIMER_A,
+	TIMER_B,
+	TIMER_C,
+	TIMER_D,
+	TIMER_E,
+	TIMER_F,
+	TIMER_G,
+	TIMER_H,
+};
+
+#define CONTROL(t)	((t)*8)
+#define COUNT(t)	((t)*8 + 4)
+
+#define CONTROL_DISABLE		0
+#define CONTROL_ENABLE		BIT(0)
+#define CONTROL_MODE(m)		((m) << 4)
+#define CONTROL_MODE_ONESHOT	CONTROL_MODE(1)
+#define CONTROL_MODE_PERIODIC	CONTROL_MODE(2)
+
+static struct dc_dev_t {
+	void __iomem *timer_base;
+	u32 ticks_per_jiffy;
+} dc_dev;
+
+static void digicolor_clkevt_mode(enum clock_event_mode mode,
+				  struct clock_event_device *clk)
+{
+	switch (mode) {
+	case CLOCK_EVT_MODE_PERIODIC:
+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
+		writel(dc_dev.ticks_per_jiffy,
+		       dc_dev.timer_base + COUNT(TIMER_C));
+		writeb(CONTROL_ENABLE | CONTROL_MODE_PERIODIC,
+		       dc_dev.timer_base + CONTROL(TIMER_C));
+		break;
+	case CLOCK_EVT_MODE_ONESHOT:
+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
+		writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
+		       dc_dev.timer_base + CONTROL(TIMER_C));
+		break;
+	case CLOCK_EVT_MODE_UNUSED:
+	case CLOCK_EVT_MODE_SHUTDOWN:
+	default:
+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
+		break;
+	}
+}
+
+static int digicolor_clkevt_next_event(unsigned long evt,
+				       struct clock_event_device *unused)
+{
+	writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
+	writel(evt, dc_dev.timer_base + COUNT(TIMER_C));
+	writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
+	       dc_dev.timer_base + CONTROL(TIMER_C));
+
+	return 0;
+}
+
+static struct clock_event_device digicolor_clockevent = {
+	.name = "digicolor_tick",
+	.rating = 340,
+	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_mode = digicolor_clkevt_mode,
+	.set_next_event = digicolor_clkevt_next_event,
+};
+
+static irqreturn_t digicolor_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static u64 digicolor_timer_sched_read(void)
+{
+	return ~readl(dc_dev.timer_base + COUNT(TIMER_B));
+}
+
+static void __init digicolor_timer_init(struct device_node *node)
+{
+	unsigned long rate;
+	struct clk *clk;
+	int ret, irq;
+
+	dc_dev.timer_base =
+		of_io_request_and_map(node, 0, of_node_full_name(node));
+	if (!dc_dev.timer_base) {
+		pr_err("Can't map registers");
+		return;
+	}
+
+	irq = irq_of_parse_and_map(node, TIMER_C);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ");
+		return;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Can't get timer clock");
+		return;
+	}
+	clk_prepare_enable(clk);
+	rate = clk_get_rate(clk);
+	dc_dev.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+
+	writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_B));
+	writel(UINT_MAX, dc_dev.timer_base + COUNT(TIMER_B));
+	writeb(CONTROL_ENABLE, dc_dev.timer_base + CONTROL(TIMER_B));
+
+	sched_clock_register(digicolor_timer_sched_read, 32, rate);
+	clocksource_mmio_init(dc_dev.timer_base + COUNT(TIMER_B), node->name,
+			      rate, 340, 32, clocksource_mmio_readl_down);
+
+	ret = request_irq(irq, digicolor_timer_interrupt,
+			  IRQF_TIMER | IRQF_IRQPOLL, "digicolor_timerC",
+			  &digicolor_clockevent);
+	if (ret)
+		pr_warn("request of timer irq %d failed (%d)\n", irq, ret);
+
+	digicolor_clockevent.cpumask = cpu_possible_mask;
+	digicolor_clockevent.irq = irq;
+
+	clockevents_config_and_register(&digicolor_clockevent, rate, 0,
+					0xffffffff);
+}
+CLOCKSOURCE_OF_DECLARE(conexant_digicolor, "cnxt,cx92755-timer",
+		       digicolor_timer_init);
-- 
2.1.4


^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer
  2015-01-26  7:56 ` [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer Baruch Siach
@ 2015-01-26  9:43   ` Daniel Lezcano
  2015-01-26 10:15     ` Baruch Siach
  0 siblings, 1 reply; 7+ messages in thread
From: Daniel Lezcano @ 2015-01-26  9:43 UTC (permalink / raw)
  To: Baruch Siach, Thomas Gleixner; +Cc: linux-kernel, linux-arm-kernel

On 01/26/2015 08:56 AM, Baruch Siach wrote:
> Add clocksource driver to the Conexant CX92755 SoC, part of the Digicolor SoCs
> series. Hardware provides 8 timers, A to H. Timer A is dedicated to a future
> watchdog driver so we don't use it here. Use timer B for sched_clock, and timer
> C for clock_event.
>
> Signed-off-by: Baruch Siach <baruch@tkos.co.il>
> ---
>   drivers/clocksource/Makefile          |   1 +
>   drivers/clocksource/timer-digicolor.c | 170 ++++++++++++++++++++++++++++++++++
>   2 files changed, 171 insertions(+)
>   create mode 100644 drivers/clocksource/timer-digicolor.c
>
> diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
> index 94d90b24b56b..a993c108be67 100644
> --- a/drivers/clocksource/Makefile
> +++ b/drivers/clocksource/Makefile
> @@ -10,6 +10,7 @@ obj-$(CONFIG_SH_TIMER_TMU)	+= sh_tmu.o
>   obj-$(CONFIG_EM_TIMER_STI)	+= em_sti.o
>   obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
>   obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
> +obj-$(CONFIG_ARCH_DIGICOLOR)	+= timer-digicolor.o
>   obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
>   obj-$(CONFIG_DW_APB_TIMER_OF)	+= dw_apb_timer_of.o
>   obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
> diff --git a/drivers/clocksource/timer-digicolor.c b/drivers/clocksource/timer-digicolor.c
> new file mode 100644
> index 000000000000..c97ea7eac4a5
> --- /dev/null
> +++ b/drivers/clocksource/timer-digicolor.c
> @@ -0,0 +1,170 @@
> +/*
> + * Conexant Digicolor timer driver
> + *
> + * Author: Baruch Siach <baruch@tkos.co.il>
> + *
> + * Copyright (C) 2014 Paradox Innovation Ltd.
> + *
> + * Based on:
> + *	Allwinner SoCs hstimer driver
> + *
> + * Copyright (C) 2013 Maxime Ripard
> + *
> + * Maxime Ripard <maxime.ripard@free-electrons.com>
> + *
> + * This file is licensed under the terms of the GNU General Public
> + * License version 2.  This program is licensed "as is" without any
> + * warranty of any kind, whether express or implied.
> + */
> +
> +/*
> + * Conexant Digicolor SoCs have 8 configurable timers, named from "Timer A" to
> + * "Timer H". Timer A is the only one with watchdog support, so it is dedicated
> + * to the watchdog driver. This driver uses Timer B for sched_clock(), and
> + * Timer C for clockevents.
> + */
> +
> +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
> +
> +#include <linux/clk.h>
> +#include <linux/clockchips.h>
> +#include <linux/interrupt.h>
> +#include <linux/irq.h>
> +#include <linux/irqreturn.h>
> +#include <linux/sched_clock.h>
> +#include <linux/of.h>
> +#include <linux/of_address.h>
> +#include <linux/of_irq.h>
> +
> +enum {
> +	TIMER_A,
> +	TIMER_B,
> +	TIMER_C,
> +	TIMER_D,
> +	TIMER_E,
> +	TIMER_F,
> +	TIMER_G,
> +	TIMER_H,
> +};
> +
> +#define CONTROL(t)	((t)*8)
> +#define COUNT(t)	((t)*8 + 4)
> +
> +#define CONTROL_DISABLE		0
> +#define CONTROL_ENABLE		BIT(0)
> +#define CONTROL_MODE(m)		((m) << 4)
> +#define CONTROL_MODE_ONESHOT	CONTROL_MODE(1)
> +#define CONTROL_MODE_PERIODIC	CONTROL_MODE(2)
> +
> +static struct dc_dev_t {
> +	void __iomem *timer_base;
> +	u32 ticks_per_jiffy;
> +} dc_dev;

Hi Baruch,

your code is valid but I think there is a misunderstanding when we 
talked about the encapsulation.

I was expecting something like:

static struct digicolor_timer {
	void __iomem *base;
	u32 ticks_per_jiffy;
	int channel;
	struct clock_event_device ce;
};

struct digicolor_timer *dg_timer(struct clock_event_device *ce)
{
	return container_of(ce, struct digicolor_timer, ce);
}

So the timer could be accessed directly from the clock_event_device 
structure. The exception is the 'sched_read' and the init function where 
you will have to address directly the global variable.

Perhaps, that would be nice if you take the opportunity to encapsulate 
the enable/disable functions.

static inline void dg_timer_disable(struct clock_event_device *ce)
{
	struct digital_timer *dt = dg_timer(ce);
	writeb(CONTROL_DISABLE, dt->base + CONTROL(dt->channel));	
}

static inline void dg_timer_enable(struct clock_event_device *ce, int mode)
{
	struct digital_timer *dt = dg_timer(ce);
	writeb(CONTROL_ENABLE | mode, dt->base, CONTROL(dt->channel));
}

> +
> +static void digicolor_clkevt_mode(enum clock_event_mode mode,
> +				  struct clock_event_device *clk)

IMO, 'clk' argument name is confusing. I would suggest to use 'ce' or 
whatever.

> +{
> +	switch (mode) {
> +	case CLOCK_EVT_MODE_PERIODIC:
> +		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> +		writel(dc_dev.ticks_per_jiffy,
> +		       dc_dev.timer_base + COUNT(TIMER_C));
> +		writeb(CONTROL_ENABLE | CONTROL_MODE_PERIODIC,
> +		       dc_dev.timer_base + CONTROL(TIMER_C));

Becomes:

		dg_timer_disable(ce);
		dg_timer_enable(ce, CONTROL_MODE_PERIODIC);

...

> +		break;
> +	case CLOCK_EVT_MODE_ONESHOT:
> +		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> +		writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
> +		       dc_dev.timer_base + CONTROL(TIMER_C));


Becomes:
		dg_timer_disable(ce);
		dg_timer_enable(ce, CONTROL_MODE_ONESHOT);
	

> +		break;
> +	case CLOCK_EVT_MODE_UNUSED:
> +	case CLOCK_EVT_MODE_SHUTDOWN:
> +	default:
> +		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));

Becomes:
		dg_timer_disable(ce);

> +		break;
> +	}
> +}
> +
> +static int digicolor_clkevt_next_event(unsigned long evt,
> +				       struct clock_event_device *unused)
> +{
> +	writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> +	writel(evt, dc_dev.timer_base + COUNT(TIMER_C));
> +	writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
> +	       dc_dev.timer_base + CONTROL(TIMER_C));

Becomes:
	dg_timer_disable(ce);
	writel(evt, dg_timer(ce)->base + COUNT(dg_timer(ce)->base));
	dg_timer_enable(ce, CONTROL_MODE_ONESHOT);
> +	return 0;
> +}
> +
> +static struct clock_event_device digicolor_clockevent = {
> +	.name = "digicolor_tick",
> +	.rating = 340,
> +	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
> +	.set_mode = digicolor_clkevt_mode,
> +	.set_next_event = digicolor_clkevt_next_event,
> +};


struct digicolor_timer dg_timer = {
	
	.ce = {
		.name = "digicolor_tick",
		.rating = 340,
		.features = CLOCK_EVT_FEAT_PERIODIC |
				CLOCK_EVT_FEAT_ONESHOT,
		.set_mode = digicolor_clkevt_mode,
		.set_next_event = digicolor_clkevt_next_event,
	},
	.channel = TIMER_C,
};

What do you think ?

> +static irqreturn_t digicolor_timer_interrupt(int irq, void *dev_id)
> +{
> +	struct clock_event_device *evt = dev_id;
> +
> +	evt->event_handler(evt);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static u64 digicolor_timer_sched_read(void)
> +{
> +	return ~readl(dc_dev.timer_base + COUNT(TIMER_B));
> +}
> +
> +static void __init digicolor_timer_init(struct device_node *node)
> +{
> +	unsigned long rate;
> +	struct clk *clk;
> +	int ret, irq;
> +
> +	dc_dev.timer_base =
> +		of_io_request_and_map(node, 0, of_node_full_name(node));
> +	if (!dc_dev.timer_base) {
> +		pr_err("Can't map registers");
> +		return;
> +	}
> +
> +	irq = irq_of_parse_and_map(node, TIMER_C);
> +	if (irq <= 0) {
> +		pr_err("Can't parse IRQ");
> +		return;
> +	}
> +
> +	clk = of_clk_get(node, 0);
> +	if (IS_ERR(clk)) {
> +		pr_err("Can't get timer clock");
> +		return;
> +	}
> +	clk_prepare_enable(clk);
> +	rate = clk_get_rate(clk);
> +	dc_dev.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
> +
> +	writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_B));
> +	writel(UINT_MAX, dc_dev.timer_base + COUNT(TIMER_B));
> +	writeb(CONTROL_ENABLE, dc_dev.timer_base + CONTROL(TIMER_B));
> +
> +	sched_clock_register(digicolor_timer_sched_read, 32, rate);
> +	clocksource_mmio_init(dc_dev.timer_base + COUNT(TIMER_B), node->name,
> +			      rate, 340, 32, clocksource_mmio_readl_down);
> +
> +	ret = request_irq(irq, digicolor_timer_interrupt,
> +			  IRQF_TIMER | IRQF_IRQPOLL, "digicolor_timerC",
> +			  &digicolor_clockevent);
> +	if (ret)
> +		pr_warn("request of timer irq %d failed (%d)\n", irq, ret);
> +
> +	digicolor_clockevent.cpumask = cpu_possible_mask;
> +	digicolor_clockevent.irq = irq;
> +
> +	clockevents_config_and_register(&digicolor_clockevent, rate, 0,
> +					0xffffffff);
> +}
> +CLOCKSOURCE_OF_DECLARE(conexant_digicolor, "cnxt,cx92755-timer",
> +		       digicolor_timer_init);
>


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  <http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs

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^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer
  2015-01-26  9:43   ` Daniel Lezcano
@ 2015-01-26 10:15     ` Baruch Siach
  2015-01-26 10:26       ` Daniel Lezcano
  2015-01-26 10:38       ` Thomas Gleixner
  0 siblings, 2 replies; 7+ messages in thread
From: Baruch Siach @ 2015-01-26 10:15 UTC (permalink / raw)
  To: Daniel Lezcano; +Cc: Thomas Gleixner, linux-kernel, linux-arm-kernel

Hi Daniel,

On Mon, Jan 26, 2015 at 10:43:43AM +0100, Daniel Lezcano wrote:
[...]
> >+static struct dc_dev_t {
> >+	void __iomem *timer_base;
> >+	u32 ticks_per_jiffy;
> >+} dc_dev;
> 
> Hi Baruch,
> 
> your code is valid but I think there is a misunderstanding when we talked
> about the encapsulation.
> 
> I was expecting something like:
> 
> static struct digicolor_timer {
> 	void __iomem *base;
> 	u32 ticks_per_jiffy;
> 	int channel;
> 	struct clock_event_device ce;
> };
> 
> struct digicolor_timer *dg_timer(struct clock_event_device *ce)
> {
> 	return container_of(ce, struct digicolor_timer, ce);
> }
> 
> So the timer could be accessed directly from the clock_event_device
> structure. The exception is the 'sched_read' and the init function where you
> will have to address directly the global variable.
> 
> Perhaps, that would be nice if you take the opportunity to encapsulate the
> enable/disable functions.
> 
> static inline void dg_timer_disable(struct clock_event_device *ce)
> {
> 	struct digital_timer *dt = dg_timer(ce);
> 	writeb(CONTROL_DISABLE, dt->base + CONTROL(dt->channel));	
> }
> 
> static inline void dg_timer_enable(struct clock_event_device *ce, int mode)
> {
> 	struct digital_timer *dt = dg_timer(ce);
> 	writeb(CONTROL_ENABLE | mode, dt->base, CONTROL(dt->channel));
> }
> 
> >+
> >+static void digicolor_clkevt_mode(enum clock_event_mode mode,
> >+				  struct clock_event_device *clk)
> 
> IMO, 'clk' argument name is confusing. I would suggest to use 'ce' or
> whatever.
> 
> >+{
> >+	switch (mode) {
> >+	case CLOCK_EVT_MODE_PERIODIC:
> >+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> >+		writel(dc_dev.ticks_per_jiffy,
> >+		       dc_dev.timer_base + COUNT(TIMER_C));
> >+		writeb(CONTROL_ENABLE | CONTROL_MODE_PERIODIC,
> >+		       dc_dev.timer_base + CONTROL(TIMER_C));
> 
> Becomes:
> 
> 		dg_timer_disable(ce);
> 		dg_timer_enable(ce, CONTROL_MODE_PERIODIC);
> 
> ...
> 
> >+		break;
> >+	case CLOCK_EVT_MODE_ONESHOT:
> >+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> >+		writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
> >+		       dc_dev.timer_base + CONTROL(TIMER_C));
> 
> 
> Becomes:
> 		dg_timer_disable(ce);
> 		dg_timer_enable(ce, CONTROL_MODE_ONESHOT);
> 	
> 
> >+		break;
> >+	case CLOCK_EVT_MODE_UNUSED:
> >+	case CLOCK_EVT_MODE_SHUTDOWN:
> >+	default:
> >+		writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> 
> Becomes:
> 		dg_timer_disable(ce);
> 
> >+		break;
> >+	}
> >+}
> >+
> >+static int digicolor_clkevt_next_event(unsigned long evt,
> >+				       struct clock_event_device *unused)
> >+{
> >+	writeb(CONTROL_DISABLE, dc_dev.timer_base + CONTROL(TIMER_C));
> >+	writel(evt, dc_dev.timer_base + COUNT(TIMER_C));
> >+	writeb(CONTROL_ENABLE | CONTROL_MODE_ONESHOT,
> >+	       dc_dev.timer_base + CONTROL(TIMER_C));
> 
> Becomes:
> 	dg_timer_disable(ce);
> 	writel(evt, dg_timer(ce)->base + COUNT(dg_timer(ce)->base));
> 	dg_timer_enable(ce, CONTROL_MODE_ONESHOT);
> >+	return 0;
> >+}
> >+
> >+static struct clock_event_device digicolor_clockevent = {
> >+	.name = "digicolor_tick",
> >+	.rating = 340,
> >+	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
> >+	.set_mode = digicolor_clkevt_mode,
> >+	.set_next_event = digicolor_clkevt_next_event,
> >+};
> 
> 
> struct digicolor_timer dg_timer = {
> 	
> 	.ce = {
> 		.name = "digicolor_tick",
> 		.rating = 340,
> 		.features = CLOCK_EVT_FEAT_PERIODIC |
> 				CLOCK_EVT_FEAT_ONESHOT,
> 		.set_mode = digicolor_clkevt_mode,
> 		.set_next_event = digicolor_clkevt_next_event,
> 	},
> 	.channel = TIMER_C,
> };
> 
> What do you think ?

OK. I'll give it a try.

Thanks for your prompt response and thorough review.

baruch

-- 
     http://baruch.siach.name/blog/                  ~. .~   Tk Open Systems
=}------------------------------------------------ooO--U--Ooo------------{=
   - baruch@tkos.co.il - tel: +972.2.679.5364, http://www.tkos.co.il -

^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer
  2015-01-26 10:15     ` Baruch Siach
@ 2015-01-26 10:26       ` Daniel Lezcano
  2015-01-26 10:38       ` Thomas Gleixner
  1 sibling, 0 replies; 7+ messages in thread
From: Daniel Lezcano @ 2015-01-26 10:26 UTC (permalink / raw)
  To: Baruch Siach; +Cc: Thomas Gleixner, linux-kernel, linux-arm-kernel

On 01/26/2015 11:15 AM, Baruch Siach wrote:
> Hi Daniel,

[ ... ]

>>
>> What do you think ?
>
> OK. I'll give it a try.
>
> Thanks for your prompt response and thorough review.

Maxime Ripard just sent a patchset (patch 4/5) with some changes 
suggested above :)

http://www.spinics.net/lists/arm-kernel/msg394704.html

As you may see, the enable/disable is passing the timer channel as 
parameter while I suggested to store it in the structure. It is up to 
you to choose what fits better for your future needs.

   -- Daniel


-- 
  <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


^ permalink raw reply	[flat|nested] 7+ messages in thread

* Re: [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer
  2015-01-26 10:15     ` Baruch Siach
  2015-01-26 10:26       ` Daniel Lezcano
@ 2015-01-26 10:38       ` Thomas Gleixner
  1 sibling, 0 replies; 7+ messages in thread
From: Thomas Gleixner @ 2015-01-26 10:38 UTC (permalink / raw)
  To: Baruch Siach; +Cc: Daniel Lezcano, linux-kernel, linux-arm-kernel

On Mon, 26 Jan 2015, Baruch Siach wrote:
> Hi Daniel,
> 
> On Mon, Jan 26, 2015 at 10:43:43AM +0100, Daniel Lezcano wrote:
> > What do you think ?
> 
> OK. I'll give it a try.
> 
> Thanks for your prompt response and thorough review.

Can you please trim your replies proper? It's annoying to page through
useless quoted text to find the meat of the mail.

Thanks,

	tglx

^ permalink raw reply	[flat|nested] 7+ messages in thread

end of thread, other threads:[~2015-01-26 10:38 UTC | newest]

Thread overview: 7+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2015-01-26  7:56 [PATCH v4 0/2] clocksource: Conexant CX92755 timers support Baruch Siach
2015-01-26  7:56 ` [PATCH v4 1/2] clocksource: devicetree: document Conexant Digicolor timer binding Baruch Siach
2015-01-26  7:56 ` [PATCH v4 2/2] clocksource: driver for Conexant Digicolor SoC timer Baruch Siach
2015-01-26  9:43   ` Daniel Lezcano
2015-01-26 10:15     ` Baruch Siach
2015-01-26 10:26       ` Daniel Lezcano
2015-01-26 10:38       ` Thomas Gleixner

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