[PATCH v2 5/9] dt-bindings: add documentation of rk3036 clock controller
From: Xing Zheng <hidden>
Date: 2015-09-24 03:42:51
Also in:
linux-devicetree, linux-rockchip, lkml
On 2015?09?17? 23:09, Heiko St?bner wrote:
Am Donnerstag, 17. September 2015, 18:32:49 schrieb Xing Zheng:quoted
Add the devicetree binding for the cru on the rk3036 which quite similar structured as previous clock controllers. Signed-off-by: Xing Zheng<redacted> --- Changes in v2: None .../bindings/clock/rockchip,rk3036-cru.txt | 60 ++++++++++++++++++++ 1 file changed, 60 insertions(+) create mode 100644 Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txtdiff --git a/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txtb/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt new file mode 100644 index 0000000..ac3037a--- /dev/null +++ b/Documentation/devicetree/bindings/clock/rockchip,rk3036-cru.txt@@ -0,0 +1,60 @@ +* Rockchip RK3036 Clock and Reset Unit + +The RK3036 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,rk3036-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 lockstatus. + +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/rk3036-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,The rk3036 does not seem to use a rtc clock, so this should probably go away
Done.
quoted
+ - "ext_i2s" - external I2S clock - optional, + - "ext_hsadc" - external HSADC clock - optional, + - "ext_vip" - external VIP clock - optional, + - "ext_isp" - external ISP clock - optional, + - "ext_jtag" - external JTAG clock - optionalThere do not seem to exist external clock sources for hsadc, vip, isp and jtag in your clock tree? missing here: - ext_gmac
Yes, done.
quoted
+ +Example: Clock controller node: + + cru: cru at 20000000 { + compatible = "rockchip,rk3036-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 at 20060000 { + compatible = "snps,dw-apb-uart"; + reg =<0x20060000 0x100>; + interrupts =<GIC_SPI 20 IRQ_TYPE_LEVEL_HIGH>; + reg-shift =<2>; + reg-io-width =<4>; + clocks =<&cru SCLK_UART0>; + };
Thanks.