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Documentation / devicetree / bindings / clock / mt8173-cpu-dvfs.txt


Based on kernel version 4.13.3. Page generated on 2017-09-23 13:54 EST.

1	Device Tree Clock bindins for CPU DVFS of Mediatek MT8173 SoC
2	
3	Required properties:
4	- clocks: A list of phandle + clock-specifier pairs for the clocks listed in clock names.
5	- clock-names: Should contain the following:
6		"cpu"		- The multiplexer for clock input of CPU cluster.
7		"intermediate"	- A parent of "cpu" clock which is used as "intermediate" clock
8				  source (usually MAINPLL) when the original CPU PLL is under
9				  transition and not stable yet.
10		Please refer to Documentation/devicetree/bindings/clk/clock-bindings.txt for
11		generic clock consumer properties.
12	- proc-supply: Regulator for Vproc of CPU cluster.
13	
14	Optional properties:
15	- sram-supply: Regulator for Vsram of CPU cluster. When present, the cpufreq driver
16		       needs to do "voltage tracking" to step by step scale up/down Vproc and
17		       Vsram to fit SoC specific needs. When absent, the voltage scaling
18		       flow is handled by hardware, hence no software "voltage tracking" is
19		       needed.
20	
21	Example:
22	--------
23		cpu0: cpu@0 {
24			device_type = "cpu";
25			compatible = "arm,cortex-a53";
26			reg = <0x000>;
27			enable-method = "psci";
28			cpu-idle-states = <&CPU_SLEEP_0>;
29			clocks = <&infracfg CLK_INFRA_CA53SEL>,
30				 <&apmixedsys CLK_APMIXED_MAINPLL>;
31			clock-names = "cpu", "intermediate";
32		};
33	
34		cpu1: cpu@1 {
35			device_type = "cpu";
36			compatible = "arm,cortex-a53";
37			reg = <0x001>;
38			enable-method = "psci";
39			cpu-idle-states = <&CPU_SLEEP_0>;
40			clocks = <&infracfg CLK_INFRA_CA53SEL>,
41				 <&apmixedsys CLK_APMIXED_MAINPLL>;
42			clock-names = "cpu", "intermediate";
43		};
44	
45		cpu2: cpu@100 {
46			device_type = "cpu";
47			compatible = "arm,cortex-a57";
48			reg = <0x100>;
49			enable-method = "psci";
50			cpu-idle-states = <&CPU_SLEEP_0>;
51			clocks = <&infracfg CLK_INFRA_CA57SEL>,
52				 <&apmixedsys CLK_APMIXED_MAINPLL>;
53			clock-names = "cpu", "intermediate";
54		};
55	
56		cpu3: cpu@101 {
57			device_type = "cpu";
58			compatible = "arm,cortex-a57";
59			reg = <0x101>;
60			enable-method = "psci";
61			cpu-idle-states = <&CPU_SLEEP_0>;
62			clocks = <&infracfg CLK_INFRA_CA57SEL>,
63				 <&apmixedsys CLK_APMIXED_MAINPLL>;
64			clock-names = "cpu", "intermediate";
65		};
66	
67		&cpu0 {
68			proc-supply = <&mt6397_vpca15_reg>;
69		};
70	
71		&cpu1 {
72			proc-supply = <&mt6397_vpca15_reg>;
73		};
74	
75		&cpu2 {
76			proc-supply = <&da9211_vcpu_reg>;
77			sram-supply = <&mt6397_vsramca7_reg>;
78		};
79	
80		&cpu3 {
81			proc-supply = <&da9211_vcpu_reg>;
82			sram-supply = <&mt6397_vsramca7_reg>;
83		};
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