2019-11-25 02:07:59

by Wang, Peng 1. (NSB - CN/Hangzhou)

Subject: [PATCH v2.1] watchdog: make DesignWare watchdog allow users to set bigger timeout value

From aabaa4b709bd451e566c906e8d1dca48f92f9b12 Mon Sep 17 00:00:00 2001
From: Peng Wang <[email protected]>
Date: Wed, 20 Nov 2019 15:12:59 +0800
Subject: [PATCH v2.1] watchdog: make DesignWare watchdog allow users to set bigger
timeout value

watchdog_dev.c provides means to allow users to set bigger timeout value
than HW can support, make DesignWare watchdog align with this.

Signed-off-by: Peng Wang <[email protected]>
---

v2 -> v2.1:
- move Signed-off-by to be ahead of section separator

v1 -> v2:
- use top_s to compare with wdd->max_hw_heartbeat_ms
- update wdd->timeout in case it's greater than HW supports
- fix comments error

v1: initial version

---
drivers/watchdog/dw_wdt.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index fef7c61..12c116e 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -114,7 +114,15 @@ static int dw_wdt_set_timeout(struct watchdog_device *wdd, unsigned int top_s)
writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);

- wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
+ /*
+ * In case users set bigger timeout value than HW can support,
+ * kernel(watchdog_dev.c) helps to feed watchdog before
+ * wdd->max_hw_heartbeat_ms
+ */
+ if (top_s * 1000 <= wdd->max_hw_heartbeat_ms)
+ wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
+ else
+ wdd->timeout = top_s;

return 0;
}
--
1.8.3.1

2019-11-25 05:40:26

by Guenter Roeck

Subject: Re: [PATCH v2.1] watchdog: make DesignWare watchdog allow users to set bigger timeout value

On Mon, Nov 25, 2019 at 02:04:13AM +0000, Wang, Peng 1. (NSB - CN/Hangzhou) wrote:
> From aabaa4b709bd451e566c906e8d1dca48f92f9b12 Mon Sep 17 00:00:00 2001
> From: Peng Wang <[email protected]>
> Date: Wed, 20 Nov 2019 15:12:59 +0800
> Subject: [PATCH v2.1] watchdog: make DesignWare watchdog allow users to set bigger
> timeout value
>
> watchdog_dev.c provides means to allow users to set bigger timeout value
> than HW can support, make DesignWare watchdog align with this.
>
> Signed-off-by: Peng Wang <[email protected]>

Reviewed-by: Guenter Roeck <[email protected]>

> ---
>
> v2 -> v2.1:
> - move Signed-off-by to be ahead of section separator
>
> v1 -> v2:
> - use top_s to compare with wdd->max_hw_heartbeat_ms
> - update wdd->timeout in case it's greater than HW supports
> - fix comments error
>
> v1: initial version
>
> ---
> drivers/watchdog/dw_wdt.c | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
> index fef7c61..12c116e 100644
> --- a/drivers/watchdog/dw_wdt.c
> +++ b/drivers/watchdog/dw_wdt.c
> @@ -114,7 +114,15 @@ static int dw_wdt_set_timeout(struct watchdog_device *wdd, unsigned int top_s)
> writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
> dw_wdt->regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
>
> - wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
> + /*
> + * In case users set bigger timeout value than HW can support,
> + * kernel(watchdog_dev.c) helps to feed watchdog before
> + * wdd->max_hw_heartbeat_ms
> + */
> + if (top_s * 1000 <= wdd->max_hw_heartbeat_ms)
> + wdd->timeout = dw_wdt_top_in_seconds(dw_wdt, top_val);
> + else
> + wdd->timeout = top_s;
>
> return 0;
> }
> --
> 1.8.3.1
>