dt-bindings: clock: Add bindings for ZynqMP clock driver

Add documentation to describe Xilinx ZynqMP clock driver
bindings.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>

1 files changed, 53 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.txt b/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.txt
index 1b431d9bbe44..614bac55df86 100644
--- a/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.txt
+++ b/Documentation/devicetree/bindings/firmware/xilinx/xlnx,zynqmp-firmware.txt
@@ -17,6 +17,53 @@ Required properties:
 		  - "smc" : SMC #0, following the SMCCC
 		  - "hvc" : HVC #0, following the SMCCC
 
+--------------------------------------------------------------------------
+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
 -------
@@ -25,5 +72,11 @@ 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>, <&gt_crx_ref_clk>;
+			clock-names = "pss_ref_clk", "video_clk", "pss_alt_ref_clk","aux_ref_clk", "gt_crx_ref_clk";
+		};
 	};
 };