xref: /linux/Documentation/devicetree/bindings/clock/ti/gate.txt (revision 9f2c9170934eace462499ba0bfe042cc72900173)
1Binding for Texas Instruments gate clock.
2
3Binding status: Unstable - ABI compatibility may be broken in the future
4
5This binding uses the common clock binding[1]. This clock is
6quite much similar to the basic gate-clock [2], however,
7it supports a number of additional features. If no register
8is provided for this clock, the code assumes that a clockdomain
9will be controlled instead and the corresponding hw-ops for
10that is used.
11
12[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
13[2] Documentation/devicetree/bindings/clock/gpio-gate-clock.yaml
14[3] Documentation/devicetree/bindings/clock/ti/clockdomain.txt
15
16Required properties:
17- compatible : shall be one of:
18  "ti,gate-clock" - basic gate clock
19  "ti,wait-gate-clock" - gate clock which waits until clock is active before
20			 returning from clk_enable()
21  "ti,dss-gate-clock" - gate clock with DSS specific hardware handling
22  "ti,am35xx-gate-clock" - gate clock with AM35xx specific hardware handling
23  "ti,clkdm-gate-clock" - clockdomain gate clock, which derives its functional
24			  clock directly from a clockdomain, see [3] how
25			  to map clockdomains properly
26  "ti,hsdiv-gate-clock" - gate clock with OMAP36xx specific hardware handling,
27			  required for a hardware errata
28  "ti,composite-gate-clock" - composite gate clock, to be part of composite
29			      clock
30  "ti,composite-no-wait-gate-clock" - composite gate clock that does not wait
31				      for clock to be active before returning
32				      from clk_enable()
33- #clock-cells : from common clock binding; shall be set to 0
34- clocks : link to phandle of parent clock
35- reg : offset for register controlling adjustable gate, not needed for
36	ti,clkdm-gate-clock type
37
38Optional properties:
39- clock-output-names : from common clock binding.
40- ti,bit-shift : bit shift for programming the clock gate, invalid for
41		 ti,clkdm-gate-clock type
42- ti,set-bit-to-disable : inverts default gate programming. Setting the bit
43  gates the clock and clearing the bit ungates the clock.
44
45Examples:
46	mmchs2_fck: mmchs2_fck@48004a00 {
47		#clock-cells = <0>;
48		compatible = "ti,gate-clock";
49		clocks = <&core_96m_fck>;
50		reg = <0x0a00>;
51		ti,bit-shift = <25>;
52	};
53
54	uart4_fck_am35xx: uart4_fck_am35xx {
55		#clock-cells = <0>;
56		compatible = "ti,wait-gate-clock";
57		clocks = <&core_48m_fck>;
58		reg = <0x0a00>;
59		ti,bit-shift = <23>;
60	};
61
62	dss1_alwon_fck_3430es2: dss1_alwon_fck_3430es2@48004e00 {
63		#clock-cells = <0>;
64		compatible = "ti,dss-gate-clock";
65		clocks = <&dpll4_m4x2_ck>;
66		reg = <0x0e00>;
67		ti,bit-shift = <0>;
68	};
69
70	emac_ick: emac_ick@4800259c {
71		#clock-cells = <0>;
72		compatible = "ti,am35xx-gate-clock";
73		clocks = <&ipss_ick>;
74		reg = <0x059c>;
75		ti,bit-shift = <1>;
76	};
77
78	emu_src_ck: emu_src_ck {
79		#clock-cells = <0>;
80		compatible = "ti,clkdm-gate-clock";
81		clocks = <&emu_src_mux_ck>;
82	};
83
84	dpll4_m2x2_ck: dpll4_m2x2_ck@48004d00 {
85		#clock-cells = <0>;
86		compatible = "ti,hsdiv-gate-clock";
87		clocks = <&dpll4_m2x2_mul_ck>;
88		ti,bit-shift = <0x1b>;
89		reg = <0x0d00>;
90		ti,set-bit-to-disable;
91	};
92
93	vlynq_gate_fck: vlynq_gate_fck {
94		#clock-cells = <0>;
95		compatible = "ti,composite-gate-clock";
96		clocks = <&core_ck>;
97		ti,bit-shift = <3>;
98		reg = <0x0200>;
99	};
100
101	sys_clkout2_src_gate: sys_clkout2_src_gate {
102		#clock-cells = <0>;
103		compatible = "ti,composite-no-wait-gate-clock";
104		clocks = <&core_ck>;
105		ti,bit-shift = <15>;
106		reg = <0x0070>;
107	};
108