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| -rw-r--r-- | Documentation/devicetree/bindings/clock/zynq-7000.txt | 110 |
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diff --git a/Documentation/devicetree/bindings/clock/zynq-7000.txt b/Documentation/devicetree/bindings/clock/zynq-7000.txt new file mode 100644 index 000000000..d93746cf2 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/zynq-7000.txt @@ -0,0 +1,110 @@ +Device Tree Clock bindings for the Zynq 7000 EPP + +The Zynq EPP has several different clk providers, each with there own bindings. +The purpose of this document is to document their usage. + +See clock_bindings.txt for more information on the generic clock bindings. +See Chapter 25 of Zynq TRM for more information about Zynq clocks. + +== Clock Controller == +The clock controller is a logical abstraction of Zynq's clock tree. It reads +required input clock frequencies from the devicetree and acts as clock provider +for all clock consumers of PS clocks. + +Required properties: + - #clock-cells : Must be 1 + - compatible : "xlnx,ps7-clkc" + - reg : SLCR offset and size taken via syscon < 0x100 0x100 > + - ps-clk-frequency : Frequency of the oscillator providing ps_clk in HZ + (usually 33 MHz oscillators are used for Zynq platforms) + - clock-output-names : List of strings used to name the clock outputs. Shall be + a list of the outputs given below. + +Optional properties: + - clocks : as described in the clock bindings + - clock-names : as described in the clock bindings + - fclk-enable : Bit mask to enable FCLKs statically at boot time. + Bit [0..3] correspond to FCLK0..FCLK3. The corresponding + FCLK will only be enabled if it is actually running at + boot time. + +Clock inputs: +The following strings are optional parameters to the 'clock-names' property in +order to provide an optional (E)MIO clock source. + - swdt_ext_clk + - gem0_emio_clk + - gem1_emio_clk + - mio_clk_XX # with XX = 00..53 +... + +Clock outputs: + 0: armpll + 1: ddrpll + 2: iopll + 3: cpu_6or4x + 4: cpu_3or2x + 5: cpu_2x + 6: cpu_1x + 7: ddr2x + 8: ddr3x + 9: dci + 10: lqspi + 11: smc + 12: pcap + 13: gem0 + 14: gem1 + 15: fclk0 + 16: fclk1 + 17: fclk2 + 18: fclk3 + 19: can0 + 20: can1 + 21: sdio0 + 22: sdio1 + 23: uart0 + 24: uart1 + 25: spi0 + 26: spi1 + 27: dma + 28: usb0_aper + 29: usb1_aper + 30: gem0_aper + 31: gem1_aper + 32: sdio0_aper + 33: sdio1_aper + 34: spi0_aper + 35: spi1_aper + 36: can0_aper + 37: can1_aper + 38: i2c0_aper + 39: i2c1_aper + 40: uart0_aper + 41: uart1_aper + 42: gpio_aper + 43: lqspi_aper + 44: smc_aper + 45: swdt + 46: dbg_trc + 47: dbg_apb + +Example: + clkc: clkc@100 { + #clock-cells = <1>; + compatible = "xlnx,ps7-clkc"; + ps-clk-frequency = <33333333>; + reg = <0x100 0x100>; + clock-output-names = "armpll", "ddrpll", "iopll", "cpu_6or4x", + "cpu_3or2x", "cpu_2x", "cpu_1x", "ddr2x", "ddr3x", + "dci", "lqspi", "smc", "pcap", "gem0", "gem1", + "fclk0", "fclk1", "fclk2", "fclk3", "can0", "can1", + "sdio0", "sdio1", "uart0", "uart1", "spi0", "spi1", + "dma", "usb0_aper", "usb1_aper", "gem0_aper", + "gem1_aper", "sdio0_aper", "sdio1_aper", + "spi0_aper", "spi1_aper", "can0_aper", "can1_aper", + "i2c0_aper", "i2c1_aper", "uart0_aper", "uart1_aper", + "gpio_aper", "lqspi_aper", "smc_aper", "swdt", + "dbg_trc", "dbg_apb"; + # optional props + clocks = <&clkc 16>, <&clk_foo>; + clock-names = "gem1_emio_clk", "can_mio_clk_23"; + }; |