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@samsung.com>
---
 .../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:

-- 
2.34.1

On Fri, Aug 01, 2025 at 12:31:02PM +0200, 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@samsung.com>
> ---
>  .../devicetree/bindings/gpu/img,powervr-rogue.yaml | 33 ++++++++++++++++------
>  1 file changed, 25 insertions(+), 8 deletions(-)

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

Best regards,
Krzysztof

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@samsung.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@imgtec.com