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authorSimon Glass <sjg@chromium.org>2015-08-30 16:55:20 -0600
committerSimon Glass <sjg@chromium.org>2015-09-02 21:28:23 -0600
commit344c837686b4268882ee4942f2a1e5e5716c7383 (patch)
tree77f791f5177587b561a8560ec8c3b871249877de /doc/device-tree-bindings/clock/rockchip,rk3288-cru.txt
parent765a1b1eb397f613a1d522224221d1dd4a812888 (diff)
rockchip: Bring in RK3288 device tree file includes and bindings
Bring in required device tree files from Linux. Since mainline Linux is somewhat behind, use the files from the Chromium tree. We can re-sync once further code is acccepted upstream. Signed-off-by: Simon Glass <sjg@chromium.org>
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+* Rockchip RK3288 Clock and Reset Unit
+
+The RK3288 clock controller generates and supplies clock to various
+controllers within the SoC and also implements a reset controller for SoC
+peripherals.
+
+Required Properties:
+
+- compatible: should be "rockchip,rk3288-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 changable, 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/rk3288-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_hsadc" - external HSADC clock - optional,
+ - "ext_edp_24m" - external display port clock - optional,
+ - "ext_vip" - external VIP clock - optional,
+ - "ext_isp" - external ISP clock - optional,
+ - "ext_jtag" - external JTAG clock - optional
+
+Example: Clock controller node:
+
+ cru: cru@20000000 {
+ compatible = "rockchip,rk3188-cru";
+ reg = <0x20000000 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@10124000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x10124000 0x400>;
+ interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+ reg-shift = <2>;
+ reg-io-width = <1>;
+ clocks = <&cru SCLK_UART0>;
+ };