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Diffstat (limited to 'Documentation/devicetree/bindings')
-rw-r--r-- | Documentation/devicetree/bindings/clock/emev2-clock.txt | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/emev2-clock.txt b/Documentation/devicetree/bindings/clock/emev2-clock.txt new file mode 100644 index 000000000000..60bbb1a8c69a --- /dev/null +++ b/Documentation/devicetree/bindings/clock/emev2-clock.txt @@ -0,0 +1,98 @@ +Device tree Clock bindings for Renesas EMMA Mobile EV2 + +This binding uses the common clock binding. + +* SMU +System Management Unit described in user's manual R19UH0037EJ1000_SMU. +This is not a clock provider, but clocks under SMU depend on it. + +Required properties: +- compatible: Should be "renesas,emev2-smu" +- reg: Address and Size of SMU registers + +* SMU_CLKDIV +Function block with an input mux and a divider, which corresponds to +"Serial clock generator" in fig."Clock System Overview" of the manual, +and "xxx frequency division setting register" (XXXCLKDIV) registers. +This makes internal (neither input nor output) clock that is provided +to input of xxxGCLK block. + +Required properties: +- compatible: Should be "renesas,emev2-smu-clkdiv" +- reg: Byte offset from SMU base and Bit position in the register +- clocks: Parent clocks. Input clocks as described in clock-bindings.txt +- #clock-cells: Should be <0> + +* SMU_GCLK +Clock gating node shown as "Clock stop processing block" in the +fig."Clock System Overview" of the manual. +Registers are "xxx clock gate control register" (XXXGCLKCTRL). + +Required properties: +- compatible: Should be "renesas,emev2-smu-gclk" +- reg: Byte offset from SMU base and Bit position in the register +- clocks: Input clock as described in clock-bindings.txt +- #clock-cells: Should be <0> + +Example of provider: + +usia_u0_sclkdiv: usia_u0_sclkdiv { + compatible = "renesas,emev2-smu-clkdiv"; + reg = <0x610 0>; + clocks = <&pll3_fo>, <&pll4_fo>, <&pll1_fo>, <&osc1_fo>; + #clock-cells = <0>; +}; + +usia_u0_sclk: usia_u0_sclk { + compatible = "renesas,emev2-smu-gclk"; + reg = <0x4a0 1>; + clocks = <&usia_u0_sclkdiv>; + #clock-cells = <0>; +}; + +Example of consumer: + +uart@e1020000 { + compatible = "renesas,em-uart"; + reg = <0xe1020000 0x38>; + interrupts = <0 8 0>; + clocks = <&usia_u0_sclk>; + clock-names = "sclk"; +}; + +Example of clock-tree description: + + This describes a clock path in the clock tree + c32ki -> pll3_fo -> usia_u0_sclkdiv -> usia_u0_sclk + +smu@e0110000 { + compatible = "renesas,emev2-smu"; + reg = <0xe0110000 0x10000>; + #address-cells = <2>; + #size-cells = <0>; + + c32ki: c32ki { + compatible = "fixed-clock"; + clock-frequency = <32768>; + #clock-cells = <0>; + }; + pll3_fo: pll3_fo { + compatible = "fixed-factor-clock"; + clocks = <&c32ki>; + clock-div = <1>; + clock-mult = <7000>; + #clock-cells = <0>; + }; + usia_u0_sclkdiv: usia_u0_sclkdiv { + compatible = "renesas,emev2-smu-clkdiv"; + reg = <0x610 0>; + clocks = <&pll3_fo>; + #clock-cells = <0>; + }; + usia_u0_sclk: usia_u0_sclk { + compatible = "renesas,emev2-smu-gclk"; + reg = <0x4a0 1>; + clocks = <&usia_u0_sclkdiv>; + #clock-cells = <0>; + }; +}; |