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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 17 May 2023 21:38:15 +0200
From:   Krzysztof Kozlowski <krzysztof.kozlowski@...aro.org>
To:     Alexandre Bailon <abailon@...libre.com>, airlied@...il.com,
        daniel@...ll.ch, maarten.lankhorst@...ux.intel.com,
        mripard@...nel.org, tzimmermann@...e.de
Cc:     robh+dt@...nel.org, krzysztof.kozlowski+dt@...aro.org,
        conor+dt@...nel.org, matthias.bgg@...il.com,
        angelogioacchino.delregno@...labora.com, sumit.semwal@...aro.org,
        christian.koenig@....com, jstephan@...libre.com,
        dri-devel@...ts.freedesktop.org, devicetree@...r.kernel.org,
        linux-kernel@...r.kernel.org, linux-arm-kernel@...ts.infradead.org,
        linux-mediatek@...ts.infradead.org, linux-media@...r.kernel.org,
        linaro-mm-sig@...ts.linaro.org, khilman@...libre.com,
        nbelin@...libre.com, bero@...libre.com
Subject: Re: [PATCH 7/7] dt-bindings: Add bidings for mtk,apu-drm

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@...libre.com>
> Reviewed-by: Julien Stephan <jstephan@...libre.com>

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.

Best regards,
Krzysztof