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Diffstat (limited to 'Documentation/devicetree/bindings/clock/xlnx,zynqmp-clk.txt')
-rw-r--r-- | Documentation/devicetree/bindings/clock/xlnx,zynqmp-clk.txt | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/clock/xlnx,zynqmp-clk.txt b/Documentation/devicetree/bindings/clock/xlnx,zynqmp-clk.txt new file mode 100644 index 000000000..391ee1a60 --- /dev/null +++ b/Documentation/devicetree/bindings/clock/xlnx,zynqmp-clk.txt @@ -0,0 +1,63 @@ +-------------------------------------------------------------------------- +Device Tree Clock bindings for the Zynq Ultrascale+ MPSoC controlled using +Zynq MPSoC firmware interface +-------------------------------------------------------------------------- +The clock controller is a h/w block of Zynq Ultrascale+ MPSoC clock +tree. It reads required input clock frequencies from the devicetree and acts +as clock provider for all clock consumers of PS clocks. + +See clock_bindings.txt for more information on the generic clock bindings. + +Required properties: + - #clock-cells: Must be 1 + - compatible: Must contain: "xlnx,zynqmp-clk" + - clocks: List of clock specifiers which are external input + clocks to the given clock controller. Please refer + the next section to find the input clocks for a + given controller. + - clock-names: List of clock names which are exteral input clocks + to the given clock controller. Please refer to the + clock bindings for more details. + +Input clocks for zynqmp Ultrascale+ clock controller: + +The Zynq UltraScale+ MPSoC has one primary and four alternative reference clock +inputs. These required clock inputs are: + - pss_ref_clk (PS reference clock) + - video_clk (reference clock for video system ) + - pss_alt_ref_clk (alternative PS reference clock) + - aux_ref_clk + - gt_crx_ref_clk (transceiver reference clock) + +The following strings are optional parameters to the 'clock-names' property in +order to provide an optional (E)MIO clock source: + - swdt0_ext_clk + - swdt1_ext_clk + - gem0_emio_clk + - gem1_emio_clk + - gem2_emio_clk + - gem3_emio_clk + - mio_clk_XX # with XX = 00..77 + - mio_clk_50_or_51 #for the mux clock to gem tsu from 50 or 51 + + +Output clocks are registered based on clock information received +from firmware. Output clocks indexes are mentioned in +include/dt-bindings/clock/xlnx-zynqmp-clk.h. + +------- +Example +------- + +firmware { + zynqmp_firmware: zynqmp-firmware { + compatible = "xlnx,zynqmp-firmware"; + method = "smc"; + zynqmp_clk: clock-controller { + #clock-cells = <1>; + compatible = "xlnx,zynqmp-clk"; + clocks = <&pss_ref_clk>, <&video_clk>, <&pss_alt_ref_clk>, <&aux_ref_clk>, <>_crx_ref_clk>; + clock-names = "pss_ref_clk", "video_clk", "pss_alt_ref_clk","aux_ref_clk", "gt_crx_ref_clk"; + }; + }; +}; |