kernel/Documentation/devicetree/bindings/clock/altr_socfpga.txt
2024-07-22 17:22:30 +08:00

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Device Tree Clock bindings for Altera's SoCFPGA platform
This binding uses the common clock binding[1].
[1] Documentation/devicetree/bindings/clock/clock-bindings.txt
Required properties:
- compatible : shall be one of the following:
"altr,socfpga-pll-clock" - for a PLL clock
"altr,socfpga-perip-clock" - The peripheral clock divided from the
PLL clock.
"altr,socfpga-gate-clk" - Clocks that directly feed peripherals and
can get gated.
- reg : shall be the control register offset from CLOCK_MANAGER's base for the clock.
- clocks : shall be the input parent clock phandle for the clock. This is
either an oscillator or a pll output.
- #clock-cells : from common clock binding, shall be set to 0.
Optional properties:
- fixed-divider : If clocks have a fixed divider value, use this property.
- clk-gate : For "socfpga-gate-clk", clk-gate contains the gating register
and the bit index.
- div-reg : For "socfpga-gate-clk" and "socfpga-periph-clock", div-reg contains
the divider register, bit shift, and width.
- clk-phase : For the sdmmc_clk, contains the value of the clock phase that controls
the SDMMC CIU clock. The first value is the clk_sample(smpsel), and the second
value is the cclk_in_drv(drvsel). The clk-phase is used to enable the correct
hold/delay times that is needed for the SD/MMC CIU clock. The values of both
can be 0-315 degrees, in 45 degree increments.