Amlogic Meson8, Meson8b and Meson8m2 SoCs have a DDR clock controller in the MMCBUS registers. There is no public documentation on this, but the GPL u-boot sources from the Amlogic BSP show that: - it uses the same XTAL input as the main clock controller - it contains a PLL which seems to be implemented just like the other PLLs in this SoC - there is a power-of-two PLL post-divider Add the documentation and header file for this DDR clock controller. Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> --- .../clock/amlogic,meson8-ddr-clkc.yaml | 50 +++++++++++++++++++ include/dt-bindings/clock/meson8-ddr-clkc.h | 4 ++ 2 files changed, 54 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/amlogic,meson8-ddr-clkc.yaml create mode 100644 include/dt-bindings/clock/meson8-ddr-clkc.h diff --git a/Documentation/devicetree/bindings/clock/amlogic,meson8-ddr-clkc.yaml b/Documentation/devicetree/bindings/clock/amlogic,meson8-ddr-clkc.yaml new file mode 100644 index 000000000000..bf3ca5888485 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/amlogic,meson8-ddr-clkc.yaml @@ -0,0 +1,50 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/clock/amlogic,meson8-ddr-clkc.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Amlogic DDR Clock Controller Device Tree Bindings + +maintainers: + - Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> + +properties: + compatible: + enum: + - amlogic,meson8-ddr-clkc + - amlogic,meson8b-ddr-clkc + + reg: + maxItems: 1 + + clocks: + maxItems: 1 + + clock-names: + items: + - const: xtal + + "#clock-cells": + const: 1 + +required: + - compatible + - reg + - clocks + - clock-names + - "#clock-cells" + +additionalProperties: false + +examples: + - | + ddr_clkc: clock-controller@400 { + compatible = "amlogic,meson8-ddr-clkc"; + reg = <0x400 0x20>; + clocks = <&xtal>; + clock-names = "xtal"; + #clock-cells = <1>; + }; + +... diff --git a/include/dt-bindings/clock/meson8-ddr-clkc.h b/include/dt-bindings/clock/meson8-ddr-clkc.h new file mode 100644 index 000000000000..a8e0fa2987ab --- /dev/null +++ b/include/dt-bindings/clock/meson8-ddr-clkc.h @@ -0,0 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#define DDR_CLKID_DDR_PLL_DCO 0 +#define DDR_CLKID_DDR_PLL 1 -- 2.23.0
