arm64: renesas: add Salvator-X board support

Add initial board support for r8a7795 Salvator-X. At this point
only DEBUG0 and DEBUG1 serial ports are supported.
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Gaku Inami <gaku.inami.xw@bp.renesas.com>
Signed-off-by: Takeshi Kihara <takeshi.kihara.df@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Magnus Damm <damm+renesas@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>

Documentation/devicetree/bindings/arm/shmobile.txt

@@ -59,5 +59,7 @@ Boards:
     compatible = "renesas,marzen", "renesas,r8a7779"
   - Porter (M2-LCDP)
     compatible = "renesas,porter", "renesas,r8a7791"
+  - Salvator-X
+    compatible = "renesas,salvator-x", "renesas,r8a7795";
   - SILK (RTP0RC7794LCB00011S)
     compatible = "renesas,silk", "renesas,r8a7794"

arch/arm64/boot/dts/renesas/Makefile

+dtb-$(CONFIG_ARCH_R8A7795) += r8a7795-salvator-x.dtb
+
 always		:= $(dtb-y)
 clean-files	:= *.dtb

arch/arm64/boot/dts/renesas/r8a7795-salvator-x.dts

+/*
+ * Device Tree Source for the Salvator-X board
+ *
+ * Copyright (C) 2015 Renesas Electronics Corp.
+ *
+ * This file is licensed under the terms of the GNU General Public License
+ * version 2.  This program is licensed "as is" without any warranty of any
+ * kind, whether express or implied.
+ */
+
+/dts-v1/;
+#include "r8a7795.dtsi"
+
+/ {
+	model = "Renesas Salvator-X board based on r8a7795";
+	compatible = "renesas,salvator-x", "renesas,r8a7795";
+
+	aliases {
+		serial0 = &scif2;
+		serial1 = &scif1;
+	};
+
+	chosen {
+		bootargs = "ignore_loglevel";
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@48000000 {
+		device_type = "memory";
+		/* first 128MB is reserved for secure area. */
+		reg = <0x0 0x48000000 0x0 0x38000000>;
+	};
+};
+
+&extal_clk {
+	clock-frequency = <16666666>;
+};
+
+&pfc {
+	scif1_pins: scif1 {
+		renesas,groups = "scif1_data_a", "scif1_ctrl";
+		renesas,function = "scif1";
+	};
+	scif2_pins: scif2 {
+		renesas,groups = "scif2_data_a";
+		renesas,function = "scif2";
+	};
+};
+
+&scif1 {
+	pinctrl-0 = <&scif1_pins>;
+	pinctrl-names = "default";
+
+	status = "okay";
+};
+
+&scif2 {
+	pinctrl-0 = <&scif2_pins>;
+	pinctrl-names = "default";
+
+	status = "okay";
+};