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[PATCH v5 2/8] dt-bindings: firmware: thead,th1520: Add resets for GPU clkgen

Michal Wilczynski posted 8 patches 3 months, 3 weeks ago
There is a newer version of this series
[PATCH v5 2/8] dt-bindings: firmware: thead,th1520: Add resets for GPU clkgen
Posted by Michal Wilczynski 3 months, 3 weeks ago 
Extend the TH1520 AON to describe the GPU clkgen reset line, required
for proper GPU clock and reset sequencing.

The T-HEAD TH1520 GPU requires coordinated management of two clocks
(core and sys) and two resets (GPU core reset and GPU clkgen reset).
Only the clkgen reset is exposed at the AON level, to support SoC
specific initialization handled through a dedicated auxiliary power
sequencing driver. The GPU core reset remains described in the GPU
device node, as from the GPU driver's perspective, there is only a
single reset line [1].

This follows upstream maintainers' recommendations [2] to abstract SoC
specific details into the PM domain layer rather than exposing them to
drivers directly.

Link: https://lore.kernel.org/all/816db99d-7088-4c1a-af03-b9a825ac09dc@imgtec.com/ - [1]
Link: https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/ - [2]

Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
---
 Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
index bbc183200400de7aadbb21fea21911f6f4227b09..3365124c7fd4736922717bd31caa13272f4a4ea6 100644
--- a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
+++ b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
@@ -32,6 +32,13 @@ properties:
     items:
       - const: aon
 
+  resets:
+    maxItems: 1
+
+  reset-names:
+    items:
+      - const: gpu-clkgen
+
   "#power-domain-cells":
     const: 1
 

-- 
2.34.1
Re: [PATCH v5 2/8] dt-bindings: firmware: thead,th1520: Add resets for GPU clkgen
Posted by Krzysztof Kozlowski 3 months, 3 weeks ago 
On Wed, Jun 18, 2025 at 12:22:08PM GMT, Michal Wilczynski wrote:
> Extend the TH1520 AON to describe the GPU clkgen reset line, required
> for proper GPU clock and reset sequencing.
> 
> The T-HEAD TH1520 GPU requires coordinated management of two clocks
> (core and sys) and two resets (GPU core reset and GPU clkgen reset).
> Only the clkgen reset is exposed at the AON level, to support SoC
> specific initialization handled through a dedicated auxiliary power
> sequencing driver. The GPU core reset remains described in the GPU
> device node, as from the GPU driver's perspective, there is only a
> single reset line [1].
> 
> This follows upstream maintainers' recommendations [2] to abstract SoC
> specific details into the PM domain layer rather than exposing them to
> drivers directly.
> 
> Link: https://lore.kernel.org/all/816db99d-7088-4c1a-af03-b9a825ac09dc@imgtec.com/ - [1]
> Link: https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/ - [2]
> 
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>

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

Best regards,
Krzysztof
Re: [PATCH v5 2/8] dt-bindings: firmware: thead,th1520: Add resets for GPU clkgen
Posted by Drew Fustini 3 months, 3 weeks ago 
On Wed, Jun 18, 2025 at 12:22:08PM +0200, Michal Wilczynski wrote:
> Extend the TH1520 AON to describe the GPU clkgen reset line, required
> for proper GPU clock and reset sequencing.
> 
> The T-HEAD TH1520 GPU requires coordinated management of two clocks
> (core and sys) and two resets (GPU core reset and GPU clkgen reset).
> Only the clkgen reset is exposed at the AON level, to support SoC
> specific initialization handled through a dedicated auxiliary power
> sequencing driver. The GPU core reset remains described in the GPU
> device node, as from the GPU driver's perspective, there is only a
> single reset line [1].
> 
> This follows upstream maintainers' recommendations [2] to abstract SoC
> specific details into the PM domain layer rather than exposing them to
> drivers directly.
> 
> Link: https://lore.kernel.org/all/816db99d-7088-4c1a-af03-b9a825ac09dc@imgtec.com/ - [1]
> Link: https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/ - [2]
> 
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
> ---
>  Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml | 7 +++++++
>  1 file changed, 7 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> index bbc183200400de7aadbb21fea21911f6f4227b09..3365124c7fd4736922717bd31caa13272f4a4ea6 100644
> --- a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> +++ b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> @@ -32,6 +32,13 @@ properties:
>      items:
>        - const: aon
>  
> +  resets:
> +    maxItems: 1
> +
> +  reset-names:
> +    items:
> +      - const: gpu-clkgen
> +
>    "#power-domain-cells":
>      const: 1
>  
> 
> -- 
> 2.34.1
> 

Reviewed-by: Drew Fustini <drew@pdp7.com>

I'm wondering what tree this should go through. Ulf took the original
patch that created the binding.

Thanks,
Drew
Re: [PATCH v5 2/8] dt-bindings: firmware: thead,th1520: Add resets for GPU clkgen
Posted by Bartosz Golaszewski 3 months, 3 weeks ago 
On Wed, Jun 18, 2025 at 12:22 PM Michal Wilczynski
<m.wilczynski@samsung.com> wrote:
>
> Extend the TH1520 AON to describe the GPU clkgen reset line, required
> for proper GPU clock and reset sequencing.
>
> The T-HEAD TH1520 GPU requires coordinated management of two clocks
> (core and sys) and two resets (GPU core reset and GPU clkgen reset).
> Only the clkgen reset is exposed at the AON level, to support SoC
> specific initialization handled through a dedicated auxiliary power
> sequencing driver. The GPU core reset remains described in the GPU
> device node, as from the GPU driver's perspective, there is only a
> single reset line [1].
>
> This follows upstream maintainers' recommendations [2] to abstract SoC
> specific details into the PM domain layer rather than exposing them to
> drivers directly.
>
> Link: https://lore.kernel.org/all/816db99d-7088-4c1a-af03-b9a825ac09dc@imgtec.com/ - [1]
> Link: https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/ - [2]
>
> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
> Signed-off-by: Michal Wilczynski <m.wilczynski@samsung.com>
> ---
>  Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml | 7 +++++++
>  1 file changed, 7 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> index bbc183200400de7aadbb21fea21911f6f4227b09..3365124c7fd4736922717bd31caa13272f4a4ea6 100644
> --- a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> +++ b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
> @@ -32,6 +32,13 @@ properties:
>      items:
>        - const: aon
>
> +  resets:
> +    maxItems: 1
> +
> +  reset-names:
> +    items:
> +      - const: gpu-clkgen
> +
>    "#power-domain-cells":
>      const: 1
>
>
> --
> 2.34.1
>

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

Patchew 2.1-devel-b67e4c2

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