* [PATCH 03/23] Documentation: watchdog: at91sam9_wdt: add clocks property
2015-07-31 9:39 [PATCH 00/23] ARM: at91: Properly handle slow clock Alexandre Belloni
@ 2015-07-31 9:39 ` Alexandre Belloni
2015-07-31 9:39 ` [PATCH 16/23] watchdog: at91sam9: get and use slow clock Alexandre Belloni
` (2 subsequent siblings)
3 siblings, 0 replies; 6+ messages in thread
From: Alexandre Belloni @ 2015-07-31 9:39 UTC (permalink / raw)
To: Nicolas Ferre
Cc: Boris Brezillon, Maxime Ripard, Jean-Christophe Plagniol-Villard,
linux-arm-kernel, linux-kernel, Alexandre Belloni,
Wim Van Sebroeck, linux-watchdog
The watchdog has an input clock, the slow clock. It is required as it will
not function without it.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
---
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: linux-watchdog@vger.kernel.org
Documentation/devicetree/bindings/watchdog/atmel-wdt.txt | 2 ++
1 file changed, 2 insertions(+)
diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
index a4d869744f59..86fa6de1019b 100644
--- a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt
@@ -6,6 +6,7 @@ Required properties:
- compatible: must be "atmel,at91sam9260-wdt".
- reg: physical base address of the controller and length of memory mapped
region.
+- clocks: phandle to input clock.
Optional properties:
- timeout-sec: contains the watchdog timeout in seconds.
@@ -39,6 +40,7 @@ Example:
compatible = "atmel,at91sam9260-wdt";
reg = <0xfffffd40 0x10>;
interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
+ clocks = <&clk32k>;
timeout-sec = <15>;
atmel,watchdog-type = "hardware";
atmel,reset-type = "all";
--
2.1.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* [PATCH 16/23] watchdog: at91sam9: get and use slow clock
2015-07-31 9:39 [PATCH 00/23] ARM: at91: Properly handle slow clock Alexandre Belloni
2015-07-31 9:39 ` [PATCH 03/23] Documentation: watchdog: at91sam9_wdt: add clocks property Alexandre Belloni
@ 2015-07-31 9:39 ` Alexandre Belloni
2015-07-31 9:59 ` [PATCH 00/23] ARM: at91: Properly handle " Boris Brezillon
2015-07-31 15:21 ` Alexandre Belloni
3 siblings, 0 replies; 6+ messages in thread
From: Alexandre Belloni @ 2015-07-31 9:39 UTC (permalink / raw)
To: Nicolas Ferre
Cc: Boris Brezillon, Maxime Ripard, Jean-Christophe Plagniol-Villard,
linux-arm-kernel, linux-kernel, Alexandre Belloni,
Wim Van Sebroeck, linux-watchdog
Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system
hang") added a workaround for the slow clock as it is not properly handled
by its users.
Get and use the slow clock as it is necessary for the at91sam9 watchdog.
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
---
Cc: Wim Van Sebroeck <wim@iguana.be>
Cc: linux-watchdog@vger.kernel.org
drivers/watchdog/at91sam9_wdt.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/drivers/watchdog/at91sam9_wdt.c b/drivers/watchdog/at91sam9_wdt.c
index e4698f7c5f93..7e6acaf3ece4 100644
--- a/drivers/watchdog/at91sam9_wdt.c
+++ b/drivers/watchdog/at91sam9_wdt.c
@@ -17,6 +17,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/clk.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
@@ -90,6 +91,7 @@ struct at91wdt {
unsigned long heartbeat; /* WDT heartbeat in jiffies */
bool nowayout;
unsigned int irq;
+ struct clk *sclk;
};
/* ......................................................................... */
@@ -352,15 +354,25 @@ static int __init at91wdt_probe(struct platform_device *pdev)
if (IS_ERR(wdt->base))
return PTR_ERR(wdt->base);
+ wdt->sclk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(wdt->sclk))
+ return PTR_ERR(wdt->sclk);
+
+ err = clk_prepare_enable(wdt->sclk);
+ if (err) {
+ dev_err(&pdev->dev, "Could not enable slow clock\n");
+ return err;
+ }
+
if (pdev->dev.of_node) {
err = of_at91wdt_init(pdev->dev.of_node, wdt);
if (err)
- return err;
+ goto err_clk;
}
err = at91_wdt_init(pdev, wdt);
if (err)
- return err;
+ goto err_clk;
platform_set_drvdata(pdev, wdt);
@@ -368,6 +380,11 @@ static int __init at91wdt_probe(struct platform_device *pdev)
wdt->wdd.timeout, wdt->nowayout);
return 0;
+
+err_clk:
+ clk_disable_unprepare(wdt->sclk);
+
+ return err;
}
static int __exit at91wdt_remove(struct platform_device *pdev)
@@ -377,6 +394,7 @@ static int __exit at91wdt_remove(struct platform_device *pdev)
pr_warn("I quit now, hardware will probably reboot!\n");
del_timer(&wdt->timer);
+ clk_disable_unprepare(wdt->sclk);
return 0;
}
--
2.1.4
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH 00/23] ARM: at91: Properly handle slow clock
2015-07-31 9:39 [PATCH 00/23] ARM: at91: Properly handle slow clock Alexandre Belloni
2015-07-31 9:39 ` [PATCH 03/23] Documentation: watchdog: at91sam9_wdt: add clocks property Alexandre Belloni
2015-07-31 9:39 ` [PATCH 16/23] watchdog: at91sam9: get and use slow clock Alexandre Belloni
@ 2015-07-31 9:59 ` Boris Brezillon
2015-07-31 10:20 ` Alexandre Belloni
2015-07-31 15:21 ` Alexandre Belloni
3 siblings, 1 reply; 6+ messages in thread
From: Boris Brezillon @ 2015-07-31 9:59 UTC (permalink / raw)
To: Alexandre Belloni
Cc: Nicolas Ferre, Maxime Ripard, Jean-Christophe Plagniol-Villard,
linux-arm-kernel, linux-kernel, Alessandro Zummo, Arnd Bergmann,
Daniel Lezcano, Dmitry Eremin-Solenikov, Greg Kroah-Hartman,
linux-clk, linux-pm, linux-pwm, linux-watchdog, Michael Turquette,
rtc-linux, Sebastian Reichel, Stephen Boyd, Thierry Reding,
Thomas Gleixner, Wim Van Sebroeck
Hi Alexandre,
On Fri, 31 Jul 2015 11:39:36 +0200
Alexandre Belloni <alexandre.belloni@free-electrons.com> wrote:
> Hi,
>
> It was discovered that all the slow clock user were not properly claiming it.
> This can end up in a system hang because the last registered user is releasing
> it, and it gets disabled.
>
> commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang")
> was a workaround. This series is adding the slow clock to the necessary drivers
> to avoid the issue and then removes that workaround.
>
> The Documentation updates and DT patches should probably go through the AT91
> tree this cycle to avoid breakage.
>
> Then the other patches can go through each subsystem tree. They are trivial
> enough to also go in this cycle.
>
> The final clk patch depends on the other ones and may be taken for the next
> cycle to avoid synchronization issues.
>
> I've thrown in a cleanup for at91-reset as it avoids adding support for that
> clock to the platform data initialization
I would have squashed commit 5 to 14 into a single patch, but apart
from that it looks good to me.
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Thanks,
Boris
>
> Changes in v2:
> - statisticize the global in the atmel-st change
> - merge at91_reset_of_probe() in at91_reset_probe()
> - added patches from Boris for the TCB
> - added the slow clock to the TCB
>
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-clk@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> Cc: linux-pwm@vger.kernel.org
> Cc: linux-watchdog@vger.kernel.org
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: rtc-linux@googlegroups.com
> Cc: Sebastian Reichel <sre@kernel.org>
> Cc: Stephen Boyd <sboyd@codeaurora.org>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Wim Van Sebroeck <wim@iguana.be>
>
> Alexandre Belloni (20):
> Documentation: dt: atmel-at91: add clocks to system timer, rstc and
> shdwc
> Documentation: watchdog: at91sam9_wdt: add clocks property
> Documentation: dt: rtc: at91rm9200: add clocks property
> ARM: at91/dt: at91rm9200: use slow clock where necessary
> ARM: at91/dt: at91sam9260: use slow clock where necessary
> ARM: at91/dt: at91sam9261: use slow clock where necessary
> ARM: at91/dt: at91sam9263: use slow clock where necessary
> ARM: at91/dt: at91sam9g45: use slow clock where necessary
> ARM: at91/dt: at91sam9n12: use slow clock where necessary
> ARM: at91/dt: at91sam9rl: use slow clock where necessary
> ARM: at91/dt: at91sam9x5: use slow clock where necessary
> ARM: at91/dt: sama5d3: use slow clock where necessary
> ARM: at91/dt: sama5d4: use slow clock where necessary
> rtc: at91rm9200: get and use slow clock
> watchdog: at91sam9: get and use slow clock
> power/reset: at91-reset: remove useless at91_reset_platform_probe()
> power/reset: at91-reset: get and use slow clock
> power/reset: at91-poweroff: get and use slow clock
> clocksource: atmel-st: get and use slow clock
> clk: at91: Revert "keep slow clk enabled to prevent system hang"
>
> Boris Brezillon (3):
> Documentation: dt: atmel-at91: add slow clock to tcb
> clocksource: tcb_clksrc: fix setup_clkevents error path
> misc: atmel_tclib: get and use slow clock
>
> .../devicetree/bindings/arm/atmel-at91.txt | 13 +++--
> .../bindings/rtc/atmel,at91rm9200-rtc.txt | 2 +
> .../devicetree/bindings/watchdog/atmel-wdt.txt | 2 +
> arch/arm/boot/dts/at91rm9200.dtsi | 10 ++--
> arch/arm/boot/dts/at91sam9260.dtsi | 11 +++--
> arch/arm/boot/dts/at91sam9261.dtsi | 7 ++-
> arch/arm/boot/dts/at91sam9263.dtsi | 7 ++-
> arch/arm/boot/dts/at91sam9g45.dtsi | 12 +++--
> arch/arm/boot/dts/at91sam9n12.dtsi | 12 +++--
> arch/arm/boot/dts/at91sam9rl.dtsi | 8 ++-
> arch/arm/boot/dts/at91sam9x5.dtsi | 12 +++--
> arch/arm/boot/dts/sama5d3.dtsi | 8 ++-
> arch/arm/boot/dts/sama5d3_tcb1.dtsi | 4 +-
> arch/arm/boot/dts/sama5d4.dtsi | 12 +++--
> drivers/clk/at91/clk-slow.c | 27 ----------
> drivers/clocksource/tcb_clksrc.c | 10 +++-
> drivers/clocksource/timer-atmel-st.c | 31 ++++++++----
> drivers/misc/atmel_tclib.c | 4 ++
> drivers/power/reset/at91-poweroff.c | 13 +++++
> drivers/power/reset/at91-reset.c | 57 ++++++----------------
> drivers/pwm/pwm-atmel-tcb.c | 23 ++++++---
> drivers/rtc/rtc-at91rm9200.c | 27 ++++++++--
> drivers/watchdog/at91sam9_wdt.c | 22 ++++++++-
> include/linux/atmel_tc.h | 1 +
> 24 files changed, 206 insertions(+), 129 deletions(-)
>
--
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: [PATCH 00/23] ARM: at91: Properly handle slow clock
2015-07-31 9:59 ` [PATCH 00/23] ARM: at91: Properly handle " Boris Brezillon
@ 2015-07-31 10:20 ` Alexandre Belloni
0 siblings, 0 replies; 6+ messages in thread
From: Alexandre Belloni @ 2015-07-31 10:20 UTC (permalink / raw)
To: Boris Brezillon
Cc: Nicolas Ferre, Maxime Ripard, Jean-Christophe Plagniol-Villard,
linux-arm-kernel, linux-kernel, Alessandro Zummo, Arnd Bergmann,
Daniel Lezcano, Dmitry Eremin-Solenikov, Greg Kroah-Hartman,
linux-clk, linux-pm, linux-pwm, linux-watchdog, Michael Turquette,
rtc-linux, Sebastian Reichel, Stephen Boyd, Thierry Reding,
Thomas Gleixner, Wim Van Sebroeck
Hi,
On 31/07/2015 at 11:59:03 +0200, Boris Brezillon wrote :
> I would have squashed commit 5 to 14 into a single patch, but apart
> from that it looks good to me.
>
I wanted to clearly list were the slow clock was needed for each soc. It
actually allowed me to find one that was missing.
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 00/23] ARM: at91: Properly handle slow clock
2015-07-31 9:39 [PATCH 00/23] ARM: at91: Properly handle slow clock Alexandre Belloni
` (2 preceding siblings ...)
2015-07-31 9:59 ` [PATCH 00/23] ARM: at91: Properly handle " Boris Brezillon
@ 2015-07-31 15:21 ` Alexandre Belloni
3 siblings, 0 replies; 6+ messages in thread
From: Alexandre Belloni @ 2015-07-31 15:21 UTC (permalink / raw)
To: Nicolas Ferre
Cc: Boris Brezillon, Maxime Ripard, Jean-Christophe Plagniol-Villard,
linux-arm-kernel, linux-kernel, Alessandro Zummo, Arnd Bergmann,
Daniel Lezcano, Dmitry Eremin-Solenikov, Greg Kroah-Hartman,
linux-clk, linux-pm, linux-pwm, linux-watchdog, Michael Turquette,
rtc-linux, Sebastian Reichel, Stephen Boyd, Thierry Reding,
Thomas Gleixner, Wim Van Sebroeck
Hi,
I realize now that I forgot to add the v2 tag in the subject lines. This
is really v2 :)
On 31/07/2015 at 11:39:36 +0200, Alexandre Belloni wrote :
> Hi,
>
> It was discovered that all the slow clock user were not properly claiming it.
> This can end up in a system hang because the last registered user is releasing
> it, and it gets disabled.
>
> commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system hang")
> was a workaround. This series is adding the slow clock to the necessary drivers
> to avoid the issue and then removes that workaround.
>
> The Documentation updates and DT patches should probably go through the AT91
> tree this cycle to avoid breakage.
>
> Then the other patches can go through each subsystem tree. They are trivial
> enough to also go in this cycle.
>
> The final clk patch depends on the other ones and may be taken for the next
> cycle to avoid synchronization issues.
>
> I've thrown in a cleanup for at91-reset as it avoids adding support for that
> clock to the platform data initialization
>
> Changes in v2:
> - statisticize the global in the atmel-st change
> - merge at91_reset_of_probe() in at91_reset_probe()
> - added patches from Boris for the TCB
> - added the slow clock to the TCB
>
> Cc: Alessandro Zummo <a.zummo@towertech.it>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
> Cc: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Cc: linux-clk@vger.kernel.org
> Cc: linux-pm@vger.kernel.org
> Cc: linux-pwm@vger.kernel.org
> Cc: linux-watchdog@vger.kernel.org
> Cc: Michael Turquette <mturquette@baylibre.com>
> Cc: rtc-linux@googlegroups.com
> Cc: Sebastian Reichel <sre@kernel.org>
> Cc: Stephen Boyd <sboyd@codeaurora.org>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Wim Van Sebroeck <wim@iguana.be>
>
> Alexandre Belloni (20):
> Documentation: dt: atmel-at91: add clocks to system timer, rstc and
> shdwc
> Documentation: watchdog: at91sam9_wdt: add clocks property
> Documentation: dt: rtc: at91rm9200: add clocks property
> ARM: at91/dt: at91rm9200: use slow clock where necessary
> ARM: at91/dt: at91sam9260: use slow clock where necessary
> ARM: at91/dt: at91sam9261: use slow clock where necessary
> ARM: at91/dt: at91sam9263: use slow clock where necessary
> ARM: at91/dt: at91sam9g45: use slow clock where necessary
> ARM: at91/dt: at91sam9n12: use slow clock where necessary
> ARM: at91/dt: at91sam9rl: use slow clock where necessary
> ARM: at91/dt: at91sam9x5: use slow clock where necessary
> ARM: at91/dt: sama5d3: use slow clock where necessary
> ARM: at91/dt: sama5d4: use slow clock where necessary
> rtc: at91rm9200: get and use slow clock
> watchdog: at91sam9: get and use slow clock
> power/reset: at91-reset: remove useless at91_reset_platform_probe()
> power/reset: at91-reset: get and use slow clock
> power/reset: at91-poweroff: get and use slow clock
> clocksource: atmel-st: get and use slow clock
> clk: at91: Revert "keep slow clk enabled to prevent system hang"
>
> Boris Brezillon (3):
> Documentation: dt: atmel-at91: add slow clock to tcb
> clocksource: tcb_clksrc: fix setup_clkevents error path
> misc: atmel_tclib: get and use slow clock
>
> .../devicetree/bindings/arm/atmel-at91.txt | 13 +++--
> .../bindings/rtc/atmel,at91rm9200-rtc.txt | 2 +
> .../devicetree/bindings/watchdog/atmel-wdt.txt | 2 +
> arch/arm/boot/dts/at91rm9200.dtsi | 10 ++--
> arch/arm/boot/dts/at91sam9260.dtsi | 11 +++--
> arch/arm/boot/dts/at91sam9261.dtsi | 7 ++-
> arch/arm/boot/dts/at91sam9263.dtsi | 7 ++-
> arch/arm/boot/dts/at91sam9g45.dtsi | 12 +++--
> arch/arm/boot/dts/at91sam9n12.dtsi | 12 +++--
> arch/arm/boot/dts/at91sam9rl.dtsi | 8 ++-
> arch/arm/boot/dts/at91sam9x5.dtsi | 12 +++--
> arch/arm/boot/dts/sama5d3.dtsi | 8 ++-
> arch/arm/boot/dts/sama5d3_tcb1.dtsi | 4 +-
> arch/arm/boot/dts/sama5d4.dtsi | 12 +++--
> drivers/clk/at91/clk-slow.c | 27 ----------
> drivers/clocksource/tcb_clksrc.c | 10 +++-
> drivers/clocksource/timer-atmel-st.c | 31 ++++++++----
> drivers/misc/atmel_tclib.c | 4 ++
> drivers/power/reset/at91-poweroff.c | 13 +++++
> drivers/power/reset/at91-reset.c | 57 ++++++----------------
> drivers/pwm/pwm-atmel-tcb.c | 23 ++++++---
> drivers/rtc/rtc-at91rm9200.c | 27 ++++++++--
> drivers/watchdog/at91sam9_wdt.c | 22 ++++++++-
> include/linux/atmel_tc.h | 1 +
> 24 files changed, 206 insertions(+), 129 deletions(-)
>
> --
> 2.1.4
>
--
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com
^ permalink raw reply [flat|nested] 6+ messages in thread