Message-ID: <f0d978aa-eb78-4494-9574-01566ac28b12@imgtec.com>
Date: Mon, 4 Aug 2025 08:53:45 +0000
From: Matt Coster <Matt.Coster@...tec.com>
To: Michal Wilczynski <m.wilczynski@...sung.com>
CC: Krzysztof Kozlowski <krzk+dt@...nel.org>, Guo Ren <guoren@...nel.org>,
        Fu
 Wei <wefu@...hat.com>, Rob Herring <robh@...nel.org>,
        Conor Dooley
	<conor+dt@...nel.org>,
        Bartosz Golaszewski <brgl@...ev.pl>,
        Philipp Zabel
	<p.zabel@...gutronix.de>,
        Frank Binns <Frank.Binns@...tec.com>,
        Maarten
 Lankhorst <maarten.lankhorst@...ux.intel.com>,
        Maxime Ripard
	<mripard@...nel.org>,
        Thomas Zimmermann <tzimmermann@...e.de>,
        David Airlie
	<airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
        Paul Walmsley
	<paul.walmsley@...ive.com>,
        Palmer Dabbelt <palmer@...belt.com>,
        Albert Ou
	<aou@...s.berkeley.edu>, Alexandre Ghiti <alex@...ti.fr>,
        Ulf Hansson
	<ulf.hansson@...aro.org>,
        Marek Szyprowski <m.szyprowski@...sung.com>,
        Drew
 Fustini <fustini@...nel.org>,
        "linux-riscv@...ts.infradead.org"
	<linux-riscv@...ts.infradead.org>,
        "devicetree@...r.kernel.org"
	<devicetree@...r.kernel.org>,
        "linux-kernel@...r.kernel.org"
	<linux-kernel@...r.kernel.org>,
        "linux-pm@...r.kernel.org"
	<linux-pm@...r.kernel.org>,
        "dri-devel@...ts.freedesktop.org"
	<dri-devel@...ts.freedesktop.org>
Subject: Re: [PATCH v10 2/4] dt-bindings: gpu: img,powervr-rogue: Add TH1520
 GPU support

On 01/08/2025 11:31, Michal Wilczynski wrote:
> Rework the PowerVR Rogue GPU binding to use an explicit, per variant
> style for defining power domain properties and add support for the
> T-HEAD TH1520 SoC's GPU.
> 
> To improve clarity and precision, the binding is refactored so that
> power domain items are listed explicitly for each variant [1]. The
> previous method relied on an implicit, positional mapping between the
> `power-domains` and `power-domain-names` properties. This change
> replaces the generic rules with self contained if/then blocks for each
> GPU variant, making the relationship between power domains and their
> names explicit and unambiguous.
> 
> The generic if block for img,img-rogue, which previously required
> power-domains and power-domain-names for all variants, is removed.
> Instead, each specific GPU variant now defines its own power domain
> requirements within a self-contained if/then block, making the schema
> more explicit.
> 
> This new structure is then used to add support for the
> `thead,th1520-gpu`. While its BXM-4-64 IP has two conceptual power
> domains, the TH1520 SoC integrates them behind a single power gate. The
> new binding models this with a specific rule that enforces a single
> `power-domains` entry and disallows the `power-domain-names` property.
> 
> Link: https://lore.kernel.org/all/4d79c8dd-c5fb-442c-ac65-37e7176b0cdd@linaro.org/  [1]
> 
> Signed-off-by: Michal Wilczynski <m.wilczynski@...sung.com>

I'm happy with this version for the power domains (and I see Krzysztof
agrees with his R-b, thanks!), but somewhere in the chaos we've lost the
minItems: 3 constraint for clock{s,-names}. Would you mind adding that
as a conditional on thead,th1520-gpu?

Cheers,
Matt

> ---
>  .../devicetree/bindings/gpu/img,powervr-rogue.yaml | 33 ++++++++++++++++------
>  1 file changed, 25 insertions(+), 8 deletions(-)
> 
> diff --git a/Documentation/devicetree/bindings/gpu/img,powervr-rogue.yaml b/Documentation/devicetree/bindings/gpu/img,powervr-rogue.yaml
> index 4450e2e73b3ccf74d29f0e31e2e6687d7cbe5d65..dc53ed59331bedee2d7438288f482870714bbf46 100644
> --- a/Documentation/devicetree/bindings/gpu/img,powervr-rogue.yaml
> +++ b/Documentation/devicetree/bindings/gpu/img,powervr-rogue.yaml
> @@ -21,6 +21,11 @@ properties:
>            # work with newer dts.
>            - const: img,img-axe
>            - const: img,img-rogue
> +      - items:
> +          - enum:
> +              - thead,th1520-gpu
> +          - const: img,img-bxm-4-64
> +          - const: img,img-rogue
>        - items:
>            - enum:
>                - ti,j721s2-gpu
> @@ -77,14 +82,18 @@ required:
>  additionalProperties: false
>  
>  allOf:
> -  # Constraints added alongside the new compatible strings that would otherwise
> -  # create an ABI break.
>    - if:
>        properties:
>          compatible:
>            contains:
> -            const: img,img-rogue
> +            const: img,img-axe-1-16m
>      then:
> +      properties:
> +        power-domains:
> +          items:
> +            - description: Power domain A
> +        power-domain-names:
> +          maxItems: 1
>        required:
>          - power-domains
>          - power-domain-names
> @@ -93,13 +102,16 @@ allOf:
>        properties:
>          compatible:
>            contains:
> -            const: img,img-axe-1-16m
> +            const: thead,th1520-gpu
>      then:
>        properties:
>          power-domains:
> -          maxItems: 1
> -        power-domain-names:
> -          maxItems: 1
> +          items:
> +            - description: The single, unified power domain for the GPU on the
> +                TH1520 SoC, integrating all internal IP power domains.
> +        power-domain-names: false
> +      required:
> +        - power-domains
>  
>    - if:
>        properties:
> @@ -109,9 +121,14 @@ allOf:
>      then:
>        properties:
>          power-domains:
> -          minItems: 2
> +          items:
> +            - description: Power domain A
> +            - description: Power domain B
>          power-domain-names:
>            minItems: 2
> +      required:
> +        - power-domains
> +        - power-domain-names
>  
>    - if:
>        properties:
> 


-- 
Matt Coster
E: matt.coster@...tec.com


Download attachment "OpenPGP_signature.asc" of type "application/pgp-signature" (237 bytes)

Powered by blists - more mailing lists