The PRG_ETHERNET registers can add an RX delay in RGMII mode. This requires an internal re-timing circuit whose input clock is called "timing adjustment clock". Document this clock input so the clock can be enabled as needed. Reviewed-by: Andrew Lunn <andrew@xxxxxxx> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> --- Rob, there is a soft dependency for this patch on commit f22531438ff42c "dt-bindings: net: dwmac: increase 'maxItems' for 'clocks', 'clock-names' properties" which is currently in your dt-next branch. That commit is needed to make the dt-bindings schema validation pass, because it increases the maximum number allowed clocks for anything that extends "snps,dwmac" from three to five (here I need four clocks). .../devicetree/bindings/net/amlogic,meson-dwmac.yaml | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml index 66074314e57a..64c20c92c07d 100644 --- a/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml +++ b/Documentation/devicetree/bindings/net/amlogic,meson-dwmac.yaml @@ -40,18 +40,22 @@ allOf: then: properties: clocks: + minItems: 3 + maxItems: 4 items: - description: GMAC main clock - description: First parent clock of the internal mux - description: Second parent clock of the internal mux + - description: The clock which drives the timing adjustment logic clock-names: minItems: 3 - maxItems: 3 + maxItems: 4 items: - const: stmmaceth - const: clkin0 - const: clkin1 + - const: timing-adjustment amlogic,tx-delay-ns: $ref: /schemas/types.yaml#definitions/uint32 @@ -120,7 +124,7 @@ examples: reg = <0xc9410000 0x10000>, <0xc8834540 0x8>; interrupts = <8>; interrupt-names = "macirq"; - clocks = <&clk_eth>, <&clkc_fclk_div2>, <&clk_mpll2>; - clock-names = "stmmaceth", "clkin0", "clkin1"; + clocks = <&clk_eth>, <&clk_fclk_div2>, <&clk_mpll2>, <&clk_fclk_div2>; + clock-names = "stmmaceth", "clkin0", "clkin1", "timing-adjustment"; phy-mode = "rgmii"; }; -- 2.26.2