[PATCH RFC 01/10] dt-bindings: gpu: mali-valhall-csf: add mediatek,mt8196-mali variant

Nicolas Frattaroli
2025-09-05T10:24:10Z

The Mali-based GPU on the MediaTek MT8196 SoC is shackled to its concept
of "MFlexGraphics", which in this iteration includes an embedded MCU
that needs to be poked to power on the GPU, and is in charge of
controlling all the clocks and regulators.

In return, it lets us omit the OPP tables from the device tree, as those
can now be enumerated at runtime from the MCU.

Add the mediatek,mt8196-mali compatible, and a performance-controller
property which points to a node representing such setups. It's required
on mt8196 devices.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
.../bindings/gpu/arm,mali-valhall-csf.yaml | 36 +++++++++++++++++++++-
1 file changed, 35 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
index a5b4e00217587c5d1f889094e2fff7b76e6148eb..6df802e900b744d226395c29f8d87fb6d3282d26 100644
--- a/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
+++ b/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
@@ -19,6 +19,7 @@ properties:
- items:
- enum:
- rockchip,rk3588-mali
+ - mediatek,mt8196-mali
- const: arm,mali-valhall-csf # Mali Valhall GPU model/revision is fully discoverable

reg:
@@ -53,6 +54,13 @@ properties:
opp-table:
type: object

+ performance-controller:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description:
+ A phandle of a device that controls this GPU's power and frequency,
+ if any. If present, this is usually in the form of some specialised
+ embedded MCU.
+
power-domains:
minItems: 1
maxItems: 5
@@ -91,7 +99,6 @@ required:
- interrupts
- interrupt-names
- clocks
- - mali-supply

additionalProperties: false

@@ -105,9 +112,24 @@ allOf:
properties:
clocks:
minItems: 3
+ performance-controller: false
power-domains:
maxItems: 1
power-domain-names: false
+ required:
+ - mali-supply
+ - if:
+ properties:
+ compatible:
+ contains:
+ const: rockchip,mt8196-mali
+ then:
+ properties:
+ mali-supply: false
+ sram-supply: false
+ operating-points-v2: false
+ required:
+ - performance-controller

examples:
- |
@@ -143,5 +165,17 @@ examples:
};
};
};
+ - |
+ gpu2: gpu@48000000 {
+ compatible = "mediatek,mt8196-mali", "arm,mali-valhall-csf";
+ reg = <0x48000000 0x480000>;
+ clocks = <&mfgpll 0>;
+ clock-names = "core";
+ interrupts = <GIC_SPI 606 IRQ_TYPE_LEVEL_HIGH 0>,
+ <GIC_SPI 605 IRQ_TYPE_LEVEL_HIGH 0>,
+ <GIC_SPI 604 IRQ_TYPE_LEVEL_HIGH 0>;
+ interrupt-names = "job", "mmu", "gpu";
+ performance-controller = <&gpufreq>;
+ };

...

--
2.51.0