xref: /freebsd/sys/contrib/device-tree/Bindings/clock/vt8500.txt (revision 02e9120893770924227138ba49df1edb3896112a) 
1Device Tree Clock bindings for arch-vt8500
2
3This binding uses the common clock binding[1].
4
5[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
6
7Required properties:
8- compatible : shall be one of the following:
9	"via,vt8500-pll-clock" - for a VT8500/WM8505 PLL clock
10	"wm,wm8650-pll-clock" - for a WM8650 PLL clock
11	"wm,wm8750-pll-clock" - for a WM8750 PLL clock
12	"wm,wm8850-pll-clock" - for a WM8850 PLL clock
13	"via,vt8500-device-clock" - for a VT/WM device clock
14
15Required properties for PLL clocks:
16- reg : shall be the control register offset from PMC base for the pll clock.
17- clocks : shall be the input parent clock phandle for the clock. This should
18	be the reference clock.
19- #clock-cells : from common clock binding; shall be set to 0.
20
21Required properties for device clocks:
22- clocks : shall be the input parent clock phandle for the clock. This should
23	be a pll output.
24- #clock-cells : from common clock binding; shall be set to 0.
25
26
27Device Clocks
28
29Device clocks are required to have one or both of the following sets of
30properties:
31
32
33Gated device clocks:
34
35Required properties:
36- enable-reg : shall be the register offset from PMC base for the enable
37	register.
38- enable-bit : shall be the bit within enable-reg to enable/disable the clock.
39
40
41Divisor device clocks:
42
43Required property:
44- divisor-reg : shall be the register offset from PMC base for the divisor
45	register.
46Optional property:
47- divisor-mask : shall be the mask for the divisor register. Defaults to 0x1f
48	if not specified.
49
50
51For example:
52
53ref25: ref25M {
54	#clock-cells = <0>;
55	compatible = "fixed-clock";
56	clock-frequency = <25000000>;
57};
58
59plla: plla {
60	#clock-cells = <0>;
61	compatible = "wm,wm8650-pll-clock";
62	clocks = <&ref25>;
63	reg = <0x200>;
64};
65
66sdhc: sdhc {
67	#clock-cells = <0>;
68	compatible = "via,vt8500-device-clock";
69	clocks = <&pllb>;
70	divisor-reg = <0x328>;
71	divisor-mask = <0x3f>;
72	enable-reg = <0x254>;
73	enable-bit = <18>;
74};
75