Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU

Alexandre Courbot
2016-03-22T04:00:53Z

On 03/22/2016 10:41 AM, Rob Herring wrote:
> On Sun, Mar 20, 2016 at 1:55 AM, Alexandre Courbot <gnurou-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org> wrote:
>> On Sat, Mar 19, 2016 at 5:47 AM, Rob Herring <robh-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org> wrote:
>>> On Tue, Mar 15, 2016 at 11:58:42AM +0900, Alexandre Courbot wrote:
>>>> GM20B's definition is mostly similar to GK20A's, but requires an
>>>> additional clock.
>
> [...]
>
>>>> gpu@0,57000000 {
>>>> compatible = "nvidia,gk20a";
>>>> @@ -45,3 +49,22 @@ Example:
>>>> iommus = <&mc TEGRA_SWGROUP_GPU>;
>>>> status = "disabled";
>>>> };
>>>> +
>>>> +Example for GM20B:
>>>> +
>>>> + gpu@0,57000000 {
>>>
>>> Drop the comma and leading zero.
>>
>> Even though this is how it appears in the actual DT?
>
> Yes, those will need to get fixed, too.

Sorry, I just want to confirm that I understand why this needs to be
fixed. The parent node has #address-cells = <2>, and the practice of
specifying two cells in the node name is consistent with what I see in
http://www.devicetree.org/Device_Tree_Usage.

However in the device tree usage example one can interpret the two cells
as being two different components of the address, whereas in our case we
are using two cells because the address is 64-bit - hence we should
specify it in the name as a single entity. Is this correct?

Thanks,
Alex.