arm: add initial support for the Phytium Pomelo Board

This adds platform code and the device tree for the Phytium Pomelo Board.
The initial support comprises the UART and the PCIE.

Signed-off-by: weichangzheng <nicholas_zheng@outlook.com>

include/configs/pomelo.h

@@ -0,0 +1,38 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2021
+ * lixinde         <lixinde@phytium.com.cn>
+ * weichangzheng   <weichangzheng@phytium.com.cn>
+ */
+
+#ifndef __POMELO_CONFIG_H__
+#define __POMELO_CONFIG_H__
+
+/* SDRAM Bank #1 start address */
+#define CONFIG_SYS_SDRAM_BASE		0x80000000
+
+/* SIZE of malloc pool */
+#define CONFIG_SYS_INIT_SP_ADDR		(0x29800000 + 0x1a000)
+
+/*BOOT*/
+#define CONFIG_SYS_BOOTM_LEN		0x3c00000
+
+#ifndef CONFIG_SPL_BUILD
+#define BOOT_TARGET_DEVICES(func) \
+	func(SCSI, scsi, 0) \
+
+#include <config_distro_bootcmd.h>
+#endif
+
+/* Initial environment variables */
+#define CONFIG_EXTRA_ENV_SETTINGS		\
+	"image=Image\0" \
+	BOOTENV \
+	"scriptaddr=0x90100000\0" \
+	"kernel_addr_r=0x90200000\0" \
+	"fdt_addr_r=0x95000000\0"			\
+	"boot_fit=no\0" \
+	"fdtfile=phytium-pomelo.dtb\0" \
+
+#endif
+