summaryrefslogtreecommitdiff
path: root/Documentation
diff options
context:
space:
mode:
authorStephen Boyd <sboyd@codeaurora.org>2016-11-30 14:38:00 -0800
committerStephen Boyd <sboyd@codeaurora.org>2016-12-06 15:17:26 -0800
commite3f4358e234edeb8fa28226387026fce72e454c1 (patch)
treed478758a59ea046c21f4a738f8909cbacf9cf21b /Documentation
parent96893e101eb294bced8358fbd48cbac175977aa4 (diff)
parente44dde27949254b7da7259ab90864c211c14ade3 (diff)
Merge tag 'v4.10-rockchip-clk2' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip into clk-next
Pull rockchip clk driver updates from Heiko Stuebner: A new clock controller for the rk1108 soc (single-core Cortex-A7+DSP), a fix making sure the cpuclk rate is actually valid, before trying to set it and a copy-paste fix for the rk3399's testclk. * tag 'v4.10-rockchip-clk2' of git://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip: clk: rockchip: add clock controller for rk1108 dt-bindings: add documentation for rk1108 cru clk: rockchip: add dt-binding header for rk1108 clk: rockchip: fix copy-paste error in rk3399 testclk clk: rockchip: validity should be checked prior to cpu clock rate change
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/clock/rockchip,rk1108-cru.txt59
1 files changed, 59 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/rockchip,rk1108-cru.txt b/Documentation/devicetree/bindings/clock/rockchip,rk1108-cru.txt
new file mode 100644
index 000000000000..4da126116cf0
--- /dev/null
+++ b/Documentation/devicetree/bindings/clock/rockchip,rk1108-cru.txt
@@ -0,0 +1,59 @@
+* Rockchip RK1108 Clock and Reset Unit
+
+The RK1108 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,rk1108-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/rk1108-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,
+ - "ext_vip" - external VIP clock - optional
+ - "ext_i2s" - external I2S clock - optional
+ - "ext_gmac" - external GMAC clock - optional
+ - "hdmiphy" - external clock input derived from HDMI PHY - optional
+ - "usbphy" - external clock input derived from USB PHY - optional
+
+Example: Clock controller node:
+
+ cru: cru@20200000 {
+ compatible = "rockchip,rk1108-cru";
+ reg = <0x20200000 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@10230000 {
+ compatible = "rockchip,rk1108-uart", "snps,dw-apb-uart";
+ reg = <0x10230000 0x100>;
+ interrupts = <GIC_SPI 44 IRQ_TYPE_LEVEL_HIGH>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ clocks = <&cru SCLK_UART0>;
+ };