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-rw-r--r--Documentation/devicetree/bindings/clock/mvebu-gated-clock.txt76
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+* Gated Clock bindings for Marvell Orion SoCs
+
+Marvell Dove and Kirkwood allow some peripheral clocks to be gated to save
+some power. The clock consumer should specify the desired clock by having
+the clock ID in its "clocks" phandle cell. The clock ID is directly mapped to
+the corresponding clock gating control bit in HW to ease manual clock lookup
+in datasheet.
+
+The following is a list of provided IDs for Dove:
+ID Clock Peripheral
+-----------------------------------
+0 usb0 USB Host 0
+1 usb1 USB Host 1
+2 ge Gigabit Ethernet
+3 sata SATA Host
+4 pex0 PCIe Cntrl 0
+5 pex1 PCIe Cntrl 1
+8 sdio0 SDHCI Host 0
+9 sdio1 SDHCI Host 1
+10 nand NAND Cntrl
+11 camera Camera Cntrl
+12 i2s0 I2S Cntrl 0
+13 i2s1 I2S Cntrl 1
+15 crypto CESA engine
+21 ac97 AC97 Cntrl
+22 pdma Peripheral DMA
+23 xor0 XOR DMA 0
+24 xor1 XOR DMA 1
+30 gephy Gigabit Ethernel PHY
+Note: gephy(30) is implemented as a parent clock of ge(2)
+
+The following is a list of provided IDs for Kirkwood:
+ID Clock Peripheral
+-----------------------------------
+0 ge0 Gigabit Ethernet 0
+2 pex0 PCIe Cntrl 0
+3 usb0 USB Host 0
+4 sdio SDIO Cntrl
+5 tsu Transp. Stream Unit
+6 dunit SDRAM Cntrl
+7 runit Runit
+8 xor0 XOR DMA 0
+9 audio I2S Cntrl 0
+14 sata0 SATA Host 0
+15 sata1 SATA Host 1
+16 xor1 XOR DMA 1
+17 crypto CESA engine
+18 pex1 PCIe Cntrl 1
+19 ge1 Gigabit Ethernet 0
+20 tdm Time Division Mplx
+
+Required properties:
+- compatible : shall be one of the following:
+ "marvell,dove-gating-clock" - for Dove SoC clock gating
+ "marvell,kirkwood-gating-clock" - for Kirkwood SoC clock gating
+- reg : shall be the register address of the Clock Gating Control register
+- #clock-cells : from common clock binding; shall be set to 1
+
+Optional properties:
+- clocks : default parent clock phandle (e.g. tclk)
+
+Example:
+
+gate_clk: clock-gating-control@d0038 {
+ compatible = "marvell,dove-gating-clock";
+ reg = <0xd0038 0x4>;
+ /* default parent clock is tclk */
+ clocks = <&core_clk 0>;
+ #clock-cells = <1>;
+};
+
+sdio0: sdio@92000 {
+ compatible = "marvell,dove-sdhci";
+ /* get clk gate bit 8 (sdio0) */
+ clocks = <&gate_clk 8>;
+};