Re: [PATCH 7/7] dt-bindings: Add bidings for mtk,apu-drm

[Krzysztof Kozlowski]

On 17/05/2023 21:38, Krzysztof Kozlowski wrote:
> On 17/05/2023 16:52, Alexandre Bailon wrote:
>> This adds the device tree bindings for the APU DRM driver.
>>
>> Signed-off-by: Alexandre Bailon <abailon@xxxxxxxxxxxx>
>> Reviewed-by: Julien Stephan <jstephan@xxxxxxxxxxxx>
> 
> There are so many errors in this patch... that for sure it was not
> tested. Reduced review, except what was already said:
> 
>> ---
>>  .../devicetree/bindings/gpu/mtk,apu-drm.yaml  | 38 +++++++++++++++++++
>>  1 file changed, 38 insertions(+)
>>  create mode 100644 Documentation/devicetree/bindings/gpu/mtk,apu-drm.yaml
>>
>> diff --git a/Documentation/devicetree/bindings/gpu/mtk,apu-drm.yaml b/Documentation/devicetree/bindings/gpu/mtk,apu-drm.yaml
>> new file mode 100644
>> index 000000000000..6f432d3ea478
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/gpu/mtk,apu-drm.yaml
>> @@ -0,0 +1,38 @@
>> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/gpu/mediatek,apu-drm.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: AI Processor Unit DRM
>> +
>> +properties:
>> +  compatible:
>> +    const: mediatek,apu-drm
> 
> drm is not hardware. Drop everywhere or explain the acronym. If you
> explain it like Linux explains, then: drm is not hardware.
> 
>> +
>> +  remoteproc:
>> +    maxItems: 2
>> +    description:
>> +      Handle to remoteproc devices controlling the APU
> 
> Missing type/ref. Does not look like generic property, so missing vendor
> prefix.
> 
>> +
>> +  iova:
>> +    maxItems: 1
>> +    description:
>> +      Address and size of virtual memory that could used by the APU
> 
> So it is a reg?
> 
>> +
>> +required:
>> +  - compatible
>> +  - remoteproc
>> +  - iova
>> +
>> +additionalProperties: false
>> +
>> +examples:
>> +  - |
>> +    apu@0 {
> 
> Where is reg? @0 says you have it...
> 
>> +      compatible = "mediatek,apu-drm";
>> +      remoteproc = <&vpu0>, <&vpu1>;
>> +      iova = <0 0x60000000 0 0x10000000>;
> 
> Why would you store virtual address, not real, in DT? Let's say you have
> some randomization like KASLR. How is it going to work? Drop, it is not
> hardware property.

Actually RANDOMIZE_BASE. KASLR randomizes the physical.

Best regards,
Krzysztof