[PATCH v4 5/6] dt-bindings: add documentation of rk3399 clock controller

[robh@kernel.org (Rob Herring)]

On Fri, Feb 19, 2016 at 09:59:46AM +0800, jianqun.xu wrote:
> From: Xing Zheng <zhengxing@rock-chips.com>
> 
> Add the devicetree binding for the cru on the rk3399 which quite
> similar structured as previous clock controllers.
> 
> Signed-off-by: Xing Zheng <zhengxing@rock-chips.com>
> Signed-off-by: Jianqun Xu <jay.xu@rock-chips.com>
> ---
> changes in v4:
> - none
> changes in v3:
> - none
> changes in v2:
> - none
> 
>  .../bindings/clock/rockchip,rk3399-cru.txt         | 82 ++++++++++++++++++++++
>  1 file changed, 82 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt

Acked-by: Rob Herring <robh@kernel.org>

> 
> diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt
> new file mode 100644
> index 0000000..07bcc6e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3399-cru.txt
> @@ -0,0 +1,82 @@
> +* Rockchip RK3399 Clock and Reset Unit
> +
> +The RK3399 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,rk3399-pmucru"
> +- compatible: CRU should be "rockchip,rk3399-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/rk3399-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,
> + - "ext_i2s" - external I2S clock - optional,
> + - "ext_gmac" - external GMAC clock - optional
> + - "ext_hsadc" - external HSADC clock - optional,
> + - "ext_isp" - external ISP clock - optional,
> + - "ext_jtag" - external JTAG clock - optional
> + - "ext_vip" - external VIP clock - optional,
> + - "usbotg_out" - output clock of the pll in the otg phy
> +
> +Example: General Register Files
> +
> +	pmugrf: syscon at ff320000 {
> +		compatible = "rockchip,rk3399-pmugrf", "syscon";
> +		reg = <0x0 0xff320000 0x0 0x1000>;
> +	};
> +
> +	grf: syscon at ff770000 {
> +		compatible = "rockchip,rk3399-grf", "syscon";
> +		reg = <0x0 0xff770000 0x0 0x10000>;
> +	};
> +
> +Example: Clock controller node:
> +
> +	pmucru: pmu-clock-controller at ff750000 {
> +		compatible = "rockchip,rk3399-pmucru";
> +		reg = <0x0 0xff750000 0x0 0x1000>;
> +		#clock-cells = <1>;
> +		#reset-cells = <1>;
> +	};
> +
> +	cru: clock-controller at ff760000 {
> +		compatible = "rockchip,rk3399-cru";
> +		reg = <0x0 0xff760000 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 at ff1a0000 {
> +		compatible = "rockchip,rk3399-uart", "snps,dw-apb-uart";
> +		reg = <0x0 0xff180000 0x0 0x100>;
> +		clocks = <&cru SCLK_UART0>, <&cru PCLK_UART0>;
> +		clock-names = "baudclk", "apb_pclk";
> +		interrupts = <GIC_SPI 99 IRQ_TYPE_LEVEL_HIGH>;
> +		reg-shift = <2>;
> +		reg-io-width = <4>;
> +	};
> -- 
> 1.9.1
> 
>