Hi Pratyush,



On 15 September 2015 at 17:44, Pratyush Anand [off-list ref] wrote:

On 15/09/2015:04:43:32 PM, Dave Young wrote:

quoted

On 08/25/15 at 01:01am, fu.wei@linaro.org wrote:

quoted

From: Fu Wei <redacted>

This can be a example of adding SBSA Generic Watchdog device node
into some dts files for the Soc which contains SBSA Generic Watchdog.

Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Fu Wei <redacted>
---
 arch/arm64/boot/dts/arm/foundation-v8.dts | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/arch/arm64/boot/dts/arm/foundation-v8.dts b/arch/arm64/boot/dts/arm/foundation-v8.dts
index 4eac8dc..824431f 100644
--- a/arch/arm64/boot/dts/arm/foundation-v8.dts
+++ b/arch/arm64/boot/dts/arm/foundation-v8.dts

@@ -237,4 +237,11 @@
                    };
            };
    };
+   watchdog@2a440000 {
+           compatible = "arm,sbsa-gwdt";
+           reg = <0x0 0x2a440000 0 0x1000>,
+                   <0x0 0x2a450000 0 0x1000>;
+           interrupts = <0 27 4>;
+           timeout-sec = <10 5>;

I assume 10 is timeout, 5 is pre timeout, but in the driver code the default
value is 30/10, I think the example dts[i] should use same default values as in code.

BTW, for kdump kernel Pratyush is working on kdump on wdt enabled system.
Basiclly we expect one configure longer timeout, and kick it in shorter
period so we can get a chance to save vmcore. 10s sounds too short for the case..

Specially if D-cache is not enabled in ARM64 kexec-tool/purgatory then its more
than 2 min. Geoff has yet not agreed [1] to take D-cache support in purgatory.

[1] https://www.mail-archive.com/kexec@lists.infradead.org/msg12881.html

Great thanks for your info.
I thinks I may need to make the default pretimeout longer in example,
may be at least 30s(for kdump kernel  with  D-cache)

any thought?

~Pratyush

-- 
Best regards,

Fu Wei
Software Engineer
Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch
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