[PATCH v1 1/2] dt-bindings: firmware: thead,th1520: Add clocks and resets

Michal Wilczynski m.wilczynski at samsung.com
Wed Apr 9 02:30:24 PDT 2025


Prepare for handling GPU clock and reset sequencing through a generic
power domain by adding clock and reset properties to the TH1520 AON
firmware bindings.

The T-HEAD TH1520 GPU requires coordinated management of two clocks
(core and sys) and two resets (GPU and GPU CLKGEN). Due to SoC-specific
requirements, the CLKGEN reset must be carefully managed alongside clock
enables to ensure proper GPU operation, as discussed on the mailing list
[1].

Since the coordination is now handled through a power domain, only the
programmable clocks (core and sys) are exposed. The GPU MEM clock is
ignored, as it is not controllable on the TH1520 SoC.

This approach follows upstream maintainers' recommendations [1] to
avoid SoC-specific details leaking into the GPU driver or clock/reset
frameworks directly.

[1] - https://lore.kernel.org/all/38d9650fc11a674c8b689d6bab937acf@kernel.org/

Signed-off-by: Michal Wilczynski <m.wilczynski at samsung.com>
---
 .../bindings/firmware/thead,th1520-aon.yaml   | 28 +++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
index bbc183200400..8075874bcd6b 100644
--- a/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
+++ b/Documentation/devicetree/bindings/firmware/thead,th1520-aon.yaml
@@ -25,6 +25,16 @@ properties:
   compatible:
     const: thead,th1520-aon
 
+  clocks:
+    items:
+      - description: GPU core clock
+      - description: GPU sys clock
+
+  clock-names:
+    items:
+      - const: gpu-core
+      - const: gpu-sys
+
   mboxes:
     maxItems: 1
 
@@ -32,13 +42,27 @@ properties:
     items:
       - const: aon
 
+  resets:
+    items:
+      - description: GPU reset
+      - description: GPU CLKGEN reset
+
+  reset-names:
+    items:
+      - const: gpu
+      - const: gpu-clkgen
+
   "#power-domain-cells":
     const: 1
 
 required:
   - compatible
+  - clocks
+  - clock-names
   - mboxes
   - mbox-names
+  - resets
+  - reset-names
   - "#power-domain-cells"
 
 additionalProperties: false
@@ -47,7 +71,11 @@ examples:
   - |
     aon: aon {
         compatible = "thead,th1520-aon";
+        clocks = <&clk_vo 0>, <&clk_vo 1>;
+        clock-names = "gpu-core", "gpu-sys";
         mboxes = <&mbox_910t 1>;
         mbox-names = "aon";
+        resets = <&rst 0>, <&rst 1>;
+        reset-names = "gpu", "gpu-clkgen";
         #power-domain-cells = <1>;
     };
-- 
2.34.1




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