[PATCH v2 1/4] dt-bindings: mmc: amlogic,meson-gx-mmc: document the T7 pipeline clock
From: Lucas Tanure <hidden>
Date: 2026-09-05 15:32:47
Also in:
linux-amlogic, linux-arm-kernel, linux-clk, linux-mmc, lkml
Subsystem:
multimedia card (mmc), secure digital (sd) and sdio subsystem, open firmware and flattened device tree bindings, the rest · Maintainers:
Ulf Hansson, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
The SD/eMMC controllers of the T7 SoC are physically far from the NIC_MATRIX bus fabric, so the hardware design inserts a pipeline stage in the middle of the bus path to help timing closure. This stage is fed by its own gate clock and, when that clock is disabled, a controller that starts a DMA transfer can never complete it. Allow a fourth clock entry, named "pipeline", and require it for the amlogic,t7-mmc compatible. The other controllers of this family keep the existing three clocks. Assisted-by: Claude:claude-fable-5 Signed-off-by: Lucas Tanure <redacted> --- .../bindings/mmc/amlogic,meson-gx-mmc.yaml | 29 ++++++++++++++++++- 1 file changed, 28 insertions(+), 1 deletion(-)
diff --git a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx-mmc.yaml b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx-mmc.yaml
index 976f36de2091..12342b1d78e5 100644
--- a/Documentation/devicetree/bindings/mmc/amlogic,meson-gx-mmc.yaml
+++ b/Documentation/devicetree/bindings/mmc/amlogic,meson-gx-mmc.yaml@@ -15,6 +15,23 @@ maintainers: allOf: - $ref: mmc-controller.yaml# + - if: + properties: + compatible: + contains: + const: amlogic,t7-mmc + then: + properties: + clocks: + minItems: 4 + clock-names: + minItems: 4 + else: + properties: + clocks: + maxItems: 3 + clock-names: + maxItems: 3 properties: compatible:
@@ -38,13 +55,23 @@ properties: - description: card detect clocks: - maxItems: 3 + minItems: 3 + items: + - description: core clock + - description: clock input 0 of the internal mux + - description: clock input 1 of the internal mux + - description: + clock of the pipeline stage inserted in the bus path between + the controller and the DRAM. Without it, the controller cannot + complete DMA transfers. clock-names: + minItems: 3 items: - const: core - const: clkin0 - const: clkin1 + - const: pipeline resets: maxItems: 1
--
2.55.0