xref: /freebsd/sys/contrib/device-tree/Bindings/clock/rockchip,px30-cru.txt (revision b3e7694832e81d7a904a10f525f8797b753bf0d3)
1* Rockchip PX30 Clock and Reset Unit
2
3The PX30 clock controller generates and supplies clock to various
4controllers within the SoC and also implements a reset controller for SoC
5peripherals.
6
7Required Properties:
8
9- compatible: PMU for CRU should be "rockchip,px30-pmu-cru"
10- compatible: CRU should be "rockchip,px30-cru"
11- reg: physical base address of the controller and length of memory mapped
12  region.
13- clocks: A list of phandle + clock-specifier pairs for the clocks listed
14          in clock-names
15- clock-names: Should contain the following:
16  - "xin24m" for both PMUCRU and CRU
17  - "gpll" for CRU (sourced from PMUCRU)
18- #clock-cells: should be 1.
19- #reset-cells: should be 1.
20
21Optional Properties:
22
23- rockchip,grf: phandle to the syscon managing the "general register files"
24  If missing, pll rates are not changeable, due to the missing pll lock status.
25
26Each clock is assigned an identifier and client nodes can use this identifier
27to specify the clock which they consume. All available clocks are defined as
28preprocessor macros in the dt-bindings/clock/px30-cru.h headers and can be
29used in device tree sources. Similar macros exist for the reset sources in
30these files.
31
32External clocks:
33
34There are several clocks that are generated outside the SoC. It is expected
35that they are defined using standard clock bindings with following
36clock-output-names:
37 - "xin24m" - crystal input - required,
38 - "xin32k" - rtc clock - optional,
39 - "i2sx_clkin" - external I2S clock - optional,
40 - "gmac_clkin" - external GMAC clock - optional
41
42Example: Clock controller node:
43
44	pmucru: clock-controller@ff2bc000 {
45		compatible = "rockchip,px30-pmucru";
46		reg = <0x0 0xff2bc000 0x0 0x1000>;
47		#clock-cells = <1>;
48		#reset-cells = <1>;
49	};
50
51	cru: clock-controller@ff2b0000 {
52		compatible = "rockchip,px30-cru";
53		reg = <0x0 0xff2b0000 0x0 0x1000>;
54		rockchip,grf = <&grf>;
55		#clock-cells = <1>;
56		#reset-cells = <1>;
57	};
58
59Example: UART controller node that consumes the clock generated by the clock
60  controller:
61
62	uart0: serial@ff030000 {
63		compatible = "rockchip,px30-uart", "snps,dw-apb-uart";
64		reg = <0x0 0xff030000 0x0 0x100>;
65		interrupts = <GIC_SPI 15 IRQ_TYPE_LEVEL_HIGH>;
66		clocks = <&pmucru SCLK_UART0_PMU>, <&pmucru PCLK_UART0_PMU>;
67		clock-names = "baudclk", "apb_pclk";
68		reg-shift = <2>;
69		reg-io-width = <4>;
70	};
71