configs/nanopc_t4: new defconfig

This initial support includes:
	Linux 5.1
	Custom U-Boot
	Arm Trusted Firmware v2.0
	Buildroot default packages

Signed-off-by: Shyam Saini <shyam.saini@amarulasolutions.com>
[Thomas:
 - Use the headers from the kernel, by using
   BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_1=y
 - Use the default ext2 rootfs size]
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>

board/friendlyarm/nanopc-t4/extlinux.conf

@@ -0,0 +1,4 @@
+label NanoPc T4
+  kernel /boot/Image
+  devicetree /boot/rk3399-nanopc-t4.dtb
+  append earlycon=uart8250,mmio32,0xff1a0000 root=/dev/mmcblk1p1 rootwait

board/friendlyarm/nanopc-t4/genimage.cfg

@@ -0,0 +1,22 @@
+image sdcard.img {
+	hdimage {
+	}
+
+	partition u-boot-spl-dtb {
+		in-partition-table = "no"
+		image = "u-boot-spl-dtb.img"
+		offset = 32K
+	}
+
+	partition u-boot-dtb {
+		in-partition-table = "no"
+		image = "u-boot.itb"
+		offset = 8M
+		size = 30M
+	}
+
+	partition rootfs {
+		partition-type = 0x83
+		image = "rootfs.ext4"
+	}
+}

board/friendlyarm/nanopc-t4/post-build.sh

@@ -0,0 +1,8 @@
+#!/bin/sh
+
+MKIMAGE=$HOST_DIR/bin/mkimage
+BOARD_DIR="$(dirname $0)"
+
+$MKIMAGE -n rk3399 -T rksd -d $BINARIES_DIR/u-boot-spl-dtb.bin $BINARIES_DIR/u-boot-spl-dtb.img
+
+install -m 0644 -D $BOARD_DIR/extlinux.conf $TARGET_DIR/boot/extlinux/extlinux.conf

board/friendlyarm/nanopc-t4/readme.txt

@@ -0,0 +1,49 @@
+Intro
+=====
+
+NanoPc T4 is a RK3399 SoC based ARM64 board.
+
+Official Wiki: http://wiki.friendlyarm.com/wiki/index.php/NanoPC-T4
+
+Build
+=====
+
+Run NanoPc T4 configuration
+
+  $ make nanopc_t4_defconfig
+
+To build, run make comamnd.
+
+  $ make
+
+Files created in output directory
+=================================
+
+output/images/
+
+├── bl31.bin
+├── bl31.elf
+├── Image
+├── rk3399-nanopc-t4.dtb
+├── rootfs.ext2
+├── rootfs.ext4 -> rootfs.ext2
+├── rootfs.tar
+├── sdcard.img
+├── u-boot.bin
+├── u-boot.itb
+├── u-boot-spl-dtb.bin
+└── u-boot-spl-dtb.img
+
+Creating bootable SD card:
+=========================
+
+Simply invoke (as root)
+
+  # dd if=output/images/sdcard.img of=/dev/sdX && sync
+
+Where X is your SD card device
+
+Serial console
+--------------
+
+Baudrate for this board is 1500000