44 lines
1.4 KiB
Plaintext
44 lines
1.4 KiB
Plaintext
Rockchip EMMC PHY
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-----------------------
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Required properties:
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- compatible: rockchip,rk3399-emmc-phy
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- #phy-cells: must be 0
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- reg: PHY register address offset and length in "general
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register files"
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Optional properties:
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- clock-names: Should contain "emmcclk". Although this is listed as optional
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(because most boards can get basic functionality without having
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access to it), it is strongly suggested.
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See ../clock/clock-bindings.txt for details.
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- clocks: Should have a phandle to the card clock exported by the SDHCI driver.
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- drive-impedance-ohm: Specifies the drive impedance in Ohm.
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Possible values are 33, 40, 50, 66 and 100.
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If not set, the default value of 50 will be applied.
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- rockchip,enable-strobe-pulldown: Enable internal pull-down for the strobe
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line. If not set, pull-down is not used.
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- rockchip,output-tapdelay-select: Specifies the phyctrl_otapdlysec register.
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If not set, the register defaults to 0x4.
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Maximum value 0xf.
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Example:
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grf: syscon@ff770000 {
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compatible = "rockchip,rk3399-grf", "syscon", "simple-mfd";
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#address-cells = <1>;
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#size-cells = <1>;
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...
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emmcphy: phy@f780 {
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compatible = "rockchip,rk3399-emmc-phy";
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reg = <0xf780 0x20>;
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clocks = <&sdhci>;
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clock-names = "emmcclk";
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drive-impedance-ohm = <50>;
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#phy-cells = <0>;
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};
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};
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