Hi Arnd,

Great thanks for your time! I appreciate it, those help me a lot.
all the feedback and comment inline below :

On 4 May 2015 at 23:21, Arnd Bergmann <arnd@arndb.de> wrote:
On Monday 04 May 2015 20:04:44 fu.wei@linaro.org wrote:
> From: Fu Wei <fu.wei@linaro.org>
>
> Signed-off-by: Fu Wei <fu.wei@linaro.org>
> ---
>  .../devicetree/bindings/watchdog/sbsa-gwdt.txt     | 41 ++++++++++++++++++++++
>  1 file changed, 41 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt
>
> diff --git a/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt
> new file mode 100644
> index 0000000..14c9ec5
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/watchdog/sbsa-gwdt.txt
> @@ -0,0 +1,41 @@
> +* SBSA(Server Base System Architecture) Generic Watchdog
> +
> +The SBSA Generic Watchdog Timer is used for resuming system operation
> +after two stages of timeout.
> +More details: ARM-DEN-0029 - Server Base System Architecture (SBSA)
> +
> +Required properties:
> +- compatible : Should at least contain "arm,sbsa-gwdt".
> +
> +- reg : base physical address of the frames and length of memory mapped region.
> +
> +- reg-names : Should contain the resource reg names to show the order of
> +  the values in "reg".
> +  Must include the following entries : "refresh_frame", "control_frame".

I'd suggest naming them "refresh" and "control" without the _frame postfix.

OK, will fix it
 

> +Note that #address-cells, #size-cells, and ranges shall be present to ensure
> +the CPU can address a frame's registers.

I don't see what you mean here. These properties should only be needed if there
are child devices below the watchdog, but there are none.

For now, we only have AArch64 hardware , so
#address-cells = <2>;  #size-cells = <2>; are unnecessary,

but if there is some other Soc have this, maybe we need this. Maybe we can say:
these shall be present if the parent device's ones are different from it

or just  delete it

 

> +watchdog@2a450000 {
> +     compatible = "arm,sbsa-gwdt";
> +     #address-cells = <2>;
> +     #size-cells = <2>;
> +     reg = <0x0 0x2a450000 0 0x10000
> +            0x0 0x2a440000 0 0x10000>;

Better write this as

        reg = <0x0 0x2a450000 0 0x10000>,
              <0x0 0x2a440000 0 0x10000>;

for consistency.

OK , will fix it
 

> +     reg-names = "refresh_frame", "control_frame";
> +     interrupts = <0 27 4>;
> +     interrupt-names: "ws0"

typo.

Sorry,   "interrupt-names" ?
 

> +     timeout-sec = <10 5>;
> +};
>

        Arnd



--
Best regards,

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