From 2d1fb8e983dc0669f276b176142798a228dc0f38 Mon Sep 17 00:00:00 2001 From: Finley Xiao Date: Tue, 3 Sep 2019 19:59:45 +0800 Subject: dt-bindings: Add bindings for rk3308 clock controller Add devicetree bindings for Rockchip cru which found on Rockchip SoCs. Signed-off-by: Finley Xiao Signed-off-by: Heiko Stuebner --- .../bindings/clock/rockchip,rk3308-cru.txt | 60 ++++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/rockchip,rk3308-cru.txt (limited to 'Documentation/devicetree/bindings/clock') diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3308-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,rk3308-cru.txt new file mode 100644 index 000000000000..9b151c5b0c90 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3308-cru.txt @@ -0,0 +1,60 @@ +* Rockchip RK3308 Clock and Reset Unit + +The RK3308 clock controller generates and supplies clock to various +controllers within the SoC and also implements a reset controller for SoC +peripherals. + +Required Properties: + +- compatible: CRU should be "rockchip,rk3308-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/rk3308-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, + - "mclk_i2s0_8ch_in", "mclk_i2s1_8ch_in", "mclk_i2s2_8ch_in", + "mclk_i2s3_8ch_in", "mclk_i2s0_2ch_in", + "mclk_i2s1_2ch_in" - external I2S or SPDIF clock - optional, + - "mac_clkin" - external MAC clock - optional + +Example: Clock controller node: + + cru: clock-controller@ff500000 { + compatible = "rockchip,rk3308-cru"; + reg = <0x0 0xff500000 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@ff0a0000 { + compatible = "rockchip,rk3308-uart", "snps,dw-apb-uart"; + reg = <0x0 0xff0a0000 0x0 0x100>; + interrupts = ; + clocks = <&cru SCLK_UART0>, <&cru PCLK_UART0>; + clock-names = "baudclk", "apb_pclk"; + reg-shift = <2>; + reg-io-width = <4>; + status = "disabled"; + }; -- cgit v1.2.3-59-g8ed1b