diff mbox

[v2,1/4] watchdog: meson: Enable meson SoC specific data

Message ID 1446894139-6802-2-git-send-email-carlo@caione.org (mailing list archive)
State New, archived
Headers show

Commit Message

Carlo Caione Nov. 7, 2015, 11:02 a.m. UTC
From: Carlo Caione <carlo@endlessm.com>

With this patch we refactor the driver code to enable watchdog support
for all platforms based on Amlogic meson SoCs.

Signed-off-by: Carlo Caione <carlo@endlessm.com>
---
 drivers/watchdog/meson_wdt.c | 56 ++++++++++++++++++++++++++++++--------------
 1 file changed, 39 insertions(+), 17 deletions(-)

Comments

Guenter Roeck Nov. 7, 2015, 3:29 p.m. UTC | #1
On 11/07/2015 03:02 AM, Carlo Caione wrote:
> From: Carlo Caione <carlo@endlessm.com>
>
> With this patch we refactor the driver code to enable watchdog support
> for all platforms based on Amlogic meson SoCs.
>
> Signed-off-by: Carlo Caione <carlo@endlessm.com>
> ---
>   drivers/watchdog/meson_wdt.c | 56 ++++++++++++++++++++++++++++++--------------
>   1 file changed, 39 insertions(+), 17 deletions(-)
>
> diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
> index 1f4155e..446af94 100644
> --- a/drivers/watchdog/meson_wdt.c
> +++ b/drivers/watchdog/meson_wdt.c
> @@ -19,6 +19,7 @@
>   #include <linux/moduleparam.h>
>   #include <linux/notifier.h>
>   #include <linux/of.h>
> +#include <linux/of_device.h>
>   #include <linux/platform_device.h>
>   #include <linux/reboot.h>
>   #include <linux/types.h>
> @@ -27,35 +28,47 @@
>   #define DRV_NAME		"meson_wdt"
>
>   #define MESON_WDT_TC		0x00
> -#define MESON_WDT_TC_EN		BIT(22)
> -#define MESON_WDT_TC_TM_MASK	0x3fffff
>   #define MESON_WDT_DC_RESET	(3 << 24)
>
>   #define MESON_WDT_RESET		0x04
>
> -#define MESON_WDT_TIMEOUT	30
> +#define MESON_WDT_TIMEOUT	5

This is not a reasonable default, the change is not mentioned
in the description, and it is unrelated to the change at hand.
Sorry if I overlooked it in v1.

Guenter
Carlo Caione Nov. 7, 2015, 3:45 p.m. UTC | #2
On Sat, Nov 7, 2015 at 4:29 PM, Guenter Roeck <linux@roeck-us.net> wrote:
> On 11/07/2015 03:02 AM, Carlo Caione wrote:
>>
>> From: Carlo Caione <carlo@endlessm.com>
>>
>> With this patch we refactor the driver code to enable watchdog support
>> for all platforms based on Amlogic meson SoCs.
>>
>> Signed-off-by: Carlo Caione <carlo@endlessm.com>
>> ---
>>   drivers/watchdog/meson_wdt.c | 56
>> ++++++++++++++++++++++++++++++--------------
>>   1 file changed, 39 insertions(+), 17 deletions(-)
>>
>> diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
>> index 1f4155e..446af94 100644
>> --- a/drivers/watchdog/meson_wdt.c
>> +++ b/drivers/watchdog/meson_wdt.c
>> @@ -19,6 +19,7 @@
>>   #include <linux/moduleparam.h>
>>   #include <linux/notifier.h>
>>   #include <linux/of.h>
>> +#include <linux/of_device.h>
>>   #include <linux/platform_device.h>
>>   #include <linux/reboot.h>
>>   #include <linux/types.h>
>> @@ -27,35 +28,47 @@
>>   #define DRV_NAME              "meson_wdt"
>>
>>   #define MESON_WDT_TC          0x00
>> -#define MESON_WDT_TC_EN                BIT(22)
>> -#define MESON_WDT_TC_TM_MASK   0x3fffff
>>   #define MESON_WDT_DC_RESET    (3 << 24)
>>
>>   #define MESON_WDT_RESET               0x04
>>
>> -#define MESON_WDT_TIMEOUT      30
>> +#define MESON_WDT_TIMEOUT      5
>
>
> This is not a reasonable default, the change is not mentioned
> in the description, and it is unrelated to the change at hand.

The problem is that the default is too small or simply that the change
is not mentioned?

For the meson8b the maximum timeout is ~8 sec whereas for meson6 is
~40 sec that's why I lowered the default from 30 to 5 sec.
I can set a different default for each SoC but at least for meson8b
the value will be always < 8 sec.

Thanks,
Guenter Roeck Nov. 7, 2015, 4:37 p.m. UTC | #3
On 11/07/2015 07:45 AM, Carlo Caione wrote:
> On Sat, Nov 7, 2015 at 4:29 PM, Guenter Roeck <linux@roeck-us.net> wrote:
>> On 11/07/2015 03:02 AM, Carlo Caione wrote:
>>>
>>> From: Carlo Caione <carlo@endlessm.com>
>>>
>>> With this patch we refactor the driver code to enable watchdog support
>>> for all platforms based on Amlogic meson SoCs.
>>>
>>> Signed-off-by: Carlo Caione <carlo@endlessm.com>
>>> ---
>>>    drivers/watchdog/meson_wdt.c | 56
>>> ++++++++++++++++++++++++++++++--------------
>>>    1 file changed, 39 insertions(+), 17 deletions(-)
>>>
>>> diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
>>> index 1f4155e..446af94 100644
>>> --- a/drivers/watchdog/meson_wdt.c
>>> +++ b/drivers/watchdog/meson_wdt.c
>>> @@ -19,6 +19,7 @@
>>>    #include <linux/moduleparam.h>
>>>    #include <linux/notifier.h>
>>>    #include <linux/of.h>
>>> +#include <linux/of_device.h>
>>>    #include <linux/platform_device.h>
>>>    #include <linux/reboot.h>
>>>    #include <linux/types.h>
>>> @@ -27,35 +28,47 @@
>>>    #define DRV_NAME              "meson_wdt"
>>>
>>>    #define MESON_WDT_TC          0x00
>>> -#define MESON_WDT_TC_EN                BIT(22)
>>> -#define MESON_WDT_TC_TM_MASK   0x3fffff
>>>    #define MESON_WDT_DC_RESET    (3 << 24)
>>>
>>>    #define MESON_WDT_RESET               0x04
>>>
>>> -#define MESON_WDT_TIMEOUT      30
>>> +#define MESON_WDT_TIMEOUT      5
>>
>>
>> This is not a reasonable default, the change is not mentioned
>> in the description, and it is unrelated to the change at hand.
>
> The problem is that the default is too small or simply that the change
> is not mentioned?
>
Both.

> For the meson8b the maximum timeout is ~8 sec whereas for meson6 is
> ~40 sec that's why I lowered the default from 30 to 5 sec.
> I can set a different default for each SoC but at least for meson8b
> the value will be always < 8 sec.
>
Ok, but your change impacts both architectures. There is no reason
to hold meson6 hostage for the meson8b limitations.

An easy fix would be to set the actual timeout to min(default, max).

Thanks,
Guenter
diff mbox

Patch

diff --git a/drivers/watchdog/meson_wdt.c b/drivers/watchdog/meson_wdt.c
index 1f4155e..446af94 100644
--- a/drivers/watchdog/meson_wdt.c
+++ b/drivers/watchdog/meson_wdt.c
@@ -19,6 +19,7 @@ 
 #include <linux/moduleparam.h>
 #include <linux/notifier.h>
 #include <linux/of.h>
+#include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/reboot.h>
 #include <linux/types.h>
@@ -27,35 +28,47 @@ 
 #define DRV_NAME		"meson_wdt"
 
 #define MESON_WDT_TC		0x00
-#define MESON_WDT_TC_EN		BIT(22)
-#define MESON_WDT_TC_TM_MASK	0x3fffff
 #define MESON_WDT_DC_RESET	(3 << 24)
 
 #define MESON_WDT_RESET		0x04
 
-#define MESON_WDT_TIMEOUT	30
+#define MESON_WDT_TIMEOUT	5
 #define MESON_WDT_MIN_TIMEOUT	1
-#define MESON_WDT_MAX_TIMEOUT	(MESON_WDT_TC_TM_MASK / 100000)
 
-#define MESON_SEC_TO_TC(s)	((s) * 100000)
+#define MESON_SEC_TO_TC(s, c)	((s) * (c))
 
 static bool nowayout = WATCHDOG_NOWAYOUT;
 static unsigned int timeout = MESON_WDT_TIMEOUT;
 
+struct meson_wdt_data {
+	unsigned int enable;
+	unsigned int terminal_count_mask;
+	unsigned int count_unit;
+};
+
+static struct meson_wdt_data meson6_wdt_data = {
+	.enable			= BIT(22),
+	.terminal_count_mask	= 0x3fffff,
+	.count_unit		= 100000, /* 10 us */
+};
+
 struct meson_wdt_dev {
 	struct watchdog_device wdt_dev;
 	void __iomem *wdt_base;
 	struct notifier_block restart_handler;
+	const struct meson_wdt_data *data;
 };
 
 static int meson_restart_handle(struct notifier_block *this, unsigned long mode,
 				void *cmd)
 {
-	u32 tc_reboot = MESON_WDT_DC_RESET | MESON_WDT_TC_EN;
+	u32 tc_reboot = MESON_WDT_DC_RESET;
 	struct meson_wdt_dev *meson_wdt = container_of(this,
 						       struct meson_wdt_dev,
 						       restart_handler);
 
+	tc_reboot |= meson_wdt->data->enable;
+
 	while (1) {
 		writel(tc_reboot, meson_wdt->wdt_base + MESON_WDT_TC);
 		mdelay(5);
@@ -80,8 +93,8 @@  static void meson_wdt_change_timeout(struct watchdog_device *wdt_dev,
 	u32 reg;
 
 	reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
-	reg &= ~MESON_WDT_TC_TM_MASK;
-	reg |= MESON_SEC_TO_TC(timeout);
+	reg &= ~meson_wdt->data->terminal_count_mask;
+	reg |= MESON_SEC_TO_TC(timeout, meson_wdt->data->count_unit);
 	writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
 }
 
@@ -102,7 +115,7 @@  static int meson_wdt_stop(struct watchdog_device *wdt_dev)
 	u32 reg;
 
 	reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
-	reg &= ~MESON_WDT_TC_EN;
+	reg &= ~meson_wdt->data->enable;
 	writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
 
 	return 0;
@@ -117,7 +130,7 @@  static int meson_wdt_start(struct watchdog_device *wdt_dev)
 	meson_wdt_ping(wdt_dev);
 
 	reg = readl(meson_wdt->wdt_base + MESON_WDT_TC);
-	reg |= MESON_WDT_TC_EN;
+	reg |= meson_wdt->data->enable;
 	writel(reg, meson_wdt->wdt_base + MESON_WDT_TC);
 
 	return 0;
@@ -138,10 +151,17 @@  static const struct watchdog_ops meson_wdt_ops = {
 	.set_timeout	= meson_wdt_set_timeout,
 };
 
+static const struct of_device_id meson_wdt_dt_ids[] = {
+	{ .compatible = "amlogic,meson6-wdt", .data = &meson6_wdt_data },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, meson_wdt_dt_ids);
+
 static int meson_wdt_probe(struct platform_device *pdev)
 {
 	struct resource *res;
 	struct meson_wdt_dev *meson_wdt;
+	const struct of_device_id *of_id;
 	int err;
 
 	meson_wdt = devm_kzalloc(&pdev->dev, sizeof(*meson_wdt), GFP_KERNEL);
@@ -153,11 +173,19 @@  static int meson_wdt_probe(struct platform_device *pdev)
 	if (IS_ERR(meson_wdt->wdt_base))
 		return PTR_ERR(meson_wdt->wdt_base);
 
+	of_id = of_match_device(meson_wdt_dt_ids, &pdev->dev);
+	if (!of_id) {
+		dev_err(&pdev->dev, "Unable to initialize WDT data\n");
+		return -ENODEV;
+	}
+	meson_wdt->data = of_id->data;
+
 	meson_wdt->wdt_dev.parent = &pdev->dev;
 	meson_wdt->wdt_dev.info = &meson_wdt_info;
 	meson_wdt->wdt_dev.ops = &meson_wdt_ops;
 	meson_wdt->wdt_dev.timeout = MESON_WDT_TIMEOUT;
-	meson_wdt->wdt_dev.max_timeout = MESON_WDT_MAX_TIMEOUT;
+	meson_wdt->wdt_dev.max_timeout =
+		meson_wdt->data->terminal_count_mask / meson_wdt->data->count_unit;
 	meson_wdt->wdt_dev.min_timeout = MESON_WDT_MIN_TIMEOUT;
 
 	watchdog_set_drvdata(&meson_wdt->wdt_dev, meson_wdt);
@@ -204,12 +232,6 @@  static void meson_wdt_shutdown(struct platform_device *pdev)
 	meson_wdt_stop(&meson_wdt->wdt_dev);
 }
 
-static const struct of_device_id meson_wdt_dt_ids[] = {
-	{ .compatible = "amlogic,meson6-wdt" },
-	{ /* sentinel */ }
-};
-MODULE_DEVICE_TABLE(of, meson_wdt_dt_ids);
-
 static struct platform_driver meson_wdt_driver = {
 	.probe		= meson_wdt_probe,
 	.remove		= meson_wdt_remove,