ARM: tegra: add aliases and DMA requestor for serial nodes of Tegra114

Add APB DMA requestor and serial aliases for serial controller.
There are two serial drivers i.e. 8250 based simple serial driver
and APB DMA based serial driver for higher baudrate and performace.

The simple serial driver is selected by compatible value
"nvidia,tegra114-uart", "nvidia,tegra20-uart", and the APB DMA based
driver is selected by compatible value "nvidia,tegra114-hsuart",
"nvidia,tegra30-hsuart".

Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Signed-off-by: Stephen Warren <swarren@nvidia.com>

arch/arm/boot/dts/tegra114.dtsi

@@ -4,6 +4,13 @@
 	compatible = "nvidia,tegra114";
 	interrupt-parent = <&gic>;
 
+	aliases {
+		serial0 = &uarta;
+		serial1 = &uartb;
+		serial2 = &uartc;
+		serial3 = &uartd;
+	};
+
 	gic: interrupt-controller {
 		compatible = "arm,cortex-a15-gic";
 		#interrupt-cells = <3>;
@@ -99,38 +106,50 @@
 		       0x70003000 0x40c>;	/* Mux registers */
 	};
 
-	serial@70006000 {
+	/*
+	 * There are two serial driver i.e. 8250 based simple serial
+	 * driver and APB DMA based serial driver for higher baudrate
+	 * and performace. To enable the 8250 based driver, the compatible
+	 * is "nvidia,tegra114-uart", "nvidia,tegra20-uart" and to enable
+	 * the APB DMA based serial driver, the comptible is
+	 * "nvidia,tegra114-hsuart", "nvidia,tegra30-hsuart".
+	 */
+	uarta: serial@70006000 {
 		compatible = "nvidia,tegra114-uart", "nvidia,tegra20-uart";
 		reg = <0x70006000 0x40>;
 		reg-shift = <2>;
 		interrupts = <0 36 0x04>;
+		nvidia,dma-request-selector = <&apbdma 8>;
 		status = "disabled";
 		clocks = <&tegra_car 6>;
 	};
 
-	serial@70006040 {
+	uartb: serial@70006040 {
 		compatible = "nvidia,tegra114-uart", "nvidia,tegra20-uart";
 		reg = <0x70006040 0x40>;
 		reg-shift = <2>;
 		interrupts = <0 37 0x04>;
+		nvidia,dma-request-selector = <&apbdma 9>;
 		status = "disabled";
 		clocks = <&tegra_car 192>;
 	};
 
-	serial@70006200 {
+	uartc: serial@70006200 {
 		compatible = "nvidia,tegra114-uart", "nvidia,tegra20-uart";
 		reg = <0x70006200 0x100>;
 		reg-shift = <2>;
 		interrupts = <0 46 0x04>;
+		nvidia,dma-request-selector = <&apbdma 10>;
 		status = "disabled";
 		clocks = <&tegra_car 55>;
 	};
 
-	serial@70006300 {
+	uartd: serial@70006300 {
 		compatible = "nvidia,tegra114-uart", "nvidia,tegra20-uart";
 		reg = <0x70006300 0x100>;
 		reg-shift = <2>;
 		interrupts = <0 90 0x04>;
+		nvidia,dma-request-selector = <&apbdma 19>;
 		status = "disabled";
 		clocks = <&tegra_car 65>;
 	};