From 97752d2343518169db7e1fb9da7f2386cf2c3727 Mon Sep 17 00:00:00 2001 From: Elaine Zhang Date: Fri, 15 Jun 2018 10:16:48 +0800 Subject: [PATCH] dt-bindings: add bindings for px30 clock controller Add devicetree bindings for Rockchip cru which found on Rockchip SoCs. Signed-off-by: Elaine Zhang Reviewed-by: Rob Herring Signed-off-by: Heiko Stuebner --- .../bindings/clock/rockchip,px30-cru.txt | 65 ++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/rockchip,px30-cru.txt diff --git a/Documentation/devicetree/bindings/clock/rockchip,px30-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,px30-cru.txt new file mode 100644 index 0000000..39f0c1a --- /dev/null +++ b/Documentation/devicetree/bindings/clock/rockchip,px30-cru.txt @@ -0,0 +1,65 @@ +* Rockchip PX30 Clock and Reset Unit + +The PX30 clock controller generates and supplies clock to various +controllers within the SoC and also implements a reset controller for SoC +peripherals. + +Required Properties: + +- compatible: PMU for CRU should be "rockchip,px30-pmu-cru" +- compatible: CRU should be "rockchip,px30-cru" +- reg: physical base address of the controller and length of memory mapped + region. +- #clock-cells: should be 1. +- #reset-cells: should be 1. + +Optional Properties: + +- rockchip,grf: phandle to the syscon managing the "general register files" + If missing, pll rates are not changeable, due to the missing pll lock status. + +Each clock is assigned an identifier and client nodes can use this identifier +to specify the clock which they consume. All available clocks are defined as +preprocessor macros in the dt-bindings/clock/px30-cru.h headers and can be +used in device tree sources. Similar macros exist for the reset sources in +these files. + +External clocks: + +There are several clocks that are generated outside the SoC. It is expected +that they are defined using standard clock bindings with following +clock-output-names: + - "xin24m" - crystal input - required, + - "xin32k" - rtc clock - optional, + - "i2sx_clkin" - external I2S clock - optional, + - "gmac_clkin" - external GMAC clock - optional + +Example: Clock controller node: + + pmucru: clock-controller@ff2bc000 { + compatible = "rockchip,px30-pmucru"; + reg = <0x0 0xff2bc000 0x0 0x1000>; + #clock-cells = <1>; + #reset-cells = <1>; + }; + + cru: clock-controller@ff2b0000 { + compatible = "rockchip,px30-cru"; + reg = <0x0 0xff2b0000 0x0 0x1000>; + rockchip,grf = <&grf>; + #clock-cells = <1>; + #reset-cells = <1>; + }; + +Example: UART controller node that consumes the clock generated by the clock + controller: + + uart0: serial@ff030000 { + compatible = "rockchip,px30-uart", "snps,dw-apb-uart"; + reg = <0x0 0xff030000 0x0 0x100>; + interrupts = ; + clocks = <&pmucru SCLK_UART0_PMU>, <&pmucru PCLK_UART0_PMU>; + clock-names = "baudclk", "apb_pclk"; + reg-shift = <2>; + reg-io-width = <4>; + }; -- 2.7.4