On the MediaTek MT8196 SoC, the bitmask for which shader cores are
present and functional is not the one in the Mali GPU's registers, but
in an external efuse.

Add the nvmem cell properties to describe such a setup, and make them
required on MT8196.

Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
 .../devicetree/bindings/gpu/arm,mali-valhall-csf.yaml      | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml b/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
index bee9faf1d3f8..8eccd4338a2b 100644
--- a/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
+++ b/Documentation/devicetree/bindings/gpu/arm,mali-valhall-csf.yaml
@@ -51,6 +51,14 @@ properties:
           - stacks
       - const: stacks
 
+  nvmem-cells:
+    items:
+      - description: bitmask of functional shader cores
+
+  nvmem-cell-names:
+    items:
+      - const: shader-present
+
   mali-supply: true
 
   operating-points-v2: true
@@ -108,6 +116,8 @@ allOf:
       properties:
         clocks:
           minItems: 3
+        nvmem-cells: false
+        nvmem-cell-names: false
         power-domains:
           maxItems: 1
         power-domain-names: false
@@ -133,6 +143,8 @@ allOf:
             - const: core
             - const: stacks
       required:
+        - nvmem-cells
+        - nvmem-cell-names
         - power-domains
 
 examples:
@@ -179,6 +191,8 @@ examples:
                      <GIC_SPI 605 IRQ_TYPE_LEVEL_HIGH 0>,
                      <GIC_SPI 604 IRQ_TYPE_LEVEL_HIGH 0>;
         interrupt-names = "job", "mmu", "gpu";
+        nvmem-cells = <&shader_present>;
+        nvmem-cell-names = "shader-present";
         power-domains = <&gpufreq>;
     };
 

-- 
2.52.0