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+* Synopsys DesignWare ABP UART
+
+Required properties:
+- compatible : "snps,dw-apb-uart"
+- reg : offset and length of the register set for the device.
+- interrupts : should contain uart interrupt.
+
+Clock handling:
+The clock rate of the input clock needs to be supplied by one of
+- clock-frequency : the input clock frequency for the UART.
+- clocks : phandle to the input clock
+
+The supplying peripheral clock can also be handled, needing a second property
+- clock-names: tuple listing input clock names.
+ Required elements: "baudclk", "apb_pclk"
+
+Optional properties:
+- resets : phandle to the parent reset controller.
+- reg-shift : quantity to shift the register offsets by. If this property is
+ not present then the register offsets are not shifted.
+- reg-io-width : the size (in bytes) of the IO accesses that should be
+ performed on the device. If this property is not present then single byte
+ accesses are used.
+- dcd-override : Override the DCD modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- dsr-override : Override the DTS modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- cts-override : Override the CTS modem status signal. This signal will always
+ be reported as active instead of being obtained from the modem status
+ register. Define this if your serial port does not use this pin.
+- ri-override : Override the RI modem status signal. This signal will always be
+ reported as inactive instead of being obtained from the modem status register.
+ Define this if your serial port does not use this pin.
+
+Example:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clock-frequency = <3686400>;
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ dcd-override;
+ dsr-override;
+ cts-override;
+ ri-override;
+ };
+
+Example with one clock:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clocks = <&baudclk>;
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ };
+
+Example with two clocks:
+
+ uart@80230000 {
+ compatible = "snps,dw-apb-uart";
+ reg = <0x80230000 0x100>;
+ clocks = <&baudclk>, <&apb_pclk>;
+ clock-names = "baudclk", "apb_pclk";
+ interrupts = <10>;
+ reg-shift = <2>;
+ reg-io-width = <4>;
+ };