tegrakernel/kernel/kernel-4.9/Documentation/devicetree/bindings/clock/ti/apll.txt

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2022-02-16 09:13:02 -06:00
Binding for Texas Instruments APLL clock.
Binding status: Unstable - ABI compatibility may be broken in the future
This binding uses the common clock binding[1]. It assumes a
register-mapped APLL with usually two selectable input clocks
(reference clock and bypass clock), with analog phase locked
loop logic for multiplying the input clock to a desired output
clock. This clock also typically supports different operation
modes (locked, low power stop etc.) APLL mostly behaves like
a subtype of a DPLL [2], although a simplified one at that.
[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
[2] Documentation/devicetree/bindings/clock/ti/dpll.txt
Required properties:
- compatible : shall be "ti,dra7-apll-clock" or "ti,omap2-apll-clock"
- #clock-cells : from common clock binding; shall be set to 0.
- clocks : link phandles of parent clocks (clk-ref and clk-bypass)
- reg : address and length of the register set for controlling the APLL.
It contains the information of registers in the following order:
"control" - contains the control register offset
"idlest" - contains the idlest register offset
"autoidle" - contains the autoidle register offset (OMAP2 only)
- ti,clock-frequency : static clock frequency for the clock (OMAP2 only)
- ti,idlest-shift : bit-shift for the idlest field (OMAP2 only)
- ti,bit-shift : bit-shift for enable and autoidle fields (OMAP2 only)
Examples:
apll_pcie_ck: apll_pcie_ck {
#clock-cells = <0>;
clocks = <&apll_pcie_in_clk_mux>, <&dpll_pcie_ref_ck>;
reg = <0x021c>, <0x0220>;
compatible = "ti,dra7-apll-clock";
};
apll96_ck: apll96_ck {
#clock-cells = <0>;
compatible = "ti,omap2-apll-clock";
clocks = <&sys_ck>;
ti,bit-shift = <2>;
ti,idlest-shift = <8>;
ti,clock-frequency = <96000000>;
reg = <0x0500>, <0x0530>, <0x0520>;
};