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

From	Alexandre Courbot <acourbot@nvidia.com>
Newsgroups	linux.kernel
Subject	Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU
Date	2016-03-22 05:10 +0100
Message-ID	<rflNL-7ws-3@gated-at.bofh.it> (permalink)
References	<rcNnb-4dY-3@gated-at.bofh.it> <rcNwR-4xg-1@gated-at.bofh.it> <re9vk-824-13@gated-at.bofh.it> <reFvb-39W-7@gated-at.bofh.it> <rfjCh-5JC-7@gated-at.bofh.it>
Organization	NVIDIA

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On 03/22/2016 10:41 AM, Rob Herring wrote:
> On Sun, Mar 20, 2016 at 1:55 AM, Alexandre Courbot <gnurou@gmail.com> wrote:
>> On Sat, Mar 19, 2016 at 5:47 AM, Rob Herring <robh@kernel.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.

Thread

Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU Rob Herring <robh@kernel.org> - 2016-03-18 21:50 +0100
  Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU Alexandre Courbot <gnurou@gmail.com> - 2016-03-20 08:00 +0100
    Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU Rob Herring <robh@kernel.org> - 2016-03-22 02:50 +0100
      Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU Alexandre Courbot <acourbot@nvidia.com> - 2016-03-22 05:10 +0100
        Re: [PATCH v2 3/5] dt-bindings: Add documentation for GM20B GPU Rob Herring <robh@kernel.org> - 2016-03-22 13:50 +0100

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