riscv: sophgo: milkv_duo: initial support added

Add support for Sophgo's Milk-V Duo board, only minimal device tree and
serial console are enabled, and it can boot via vendor first stage
bootloader.

Signed-off-by: Kongyang Liu <seashell11234455@gmail.com>
Reviewed-by: Leo Yu-Chi Liang <ycliang@andestech.com>

arch/riscv/Kconfig

@@ -14,6 +14,9 @@ config TARGET_ANDES_AE350
 config TARGET_MICROCHIP_ICICLE
 	bool "Support Microchip PolarFire-SoC Icicle Board"
 
+config TARGET_MILKV_DUO
+	bool "Support Milk-v Duo Board"
+
 config TARGET_OPENPITON_RISCV64
 	bool "Support RISC-V cores on OpenPiton SoC"
 
@@ -83,6 +86,7 @@ source "board/openpiton/riscv64/Kconfig"
 source "board/sifive/unleashed/Kconfig"
 source "board/sifive/unmatched/Kconfig"
 source "board/sipeed/maix/Kconfig"
+source "board/sophgo/milkv_duo/Kconfig"
 source "board/starfive/visionfive2/Kconfig"
 source "board/thead/th1520_lpi4a/Kconfig"
 source "board/xilinx/mbv/Kconfig"

board/sophgo/milkv_duo/Kconfig

@@ -0,0 +1,28 @@
+if TARGET_MILKV_DUO
+
+config SYS_BOARD
+	default "milkv_duo"
+
+config SYS_VENDOR
+	default "sophgo"
+
+config SYS_CPU
+	default "generic"
+
+config SYS_CONFIG_NAME
+	default "milkv_duo"
+
+config TEXT_BASE
+	default 0x80200000
+
+config ENV_SIZE
+	default 0x20000
+
+config ENV_SECT_SIZE
+	default 0x40000
+
+config BOARD_SPECIFIC_OPTIONS
+	def_bool y
+	select GENERIC_RISCV
+
+endif

board/sophgo/milkv_duo/MAINTAINERS

@@ -0,0 +1,6 @@
+Milk-V Duo
+M:	Kongyang Liu <seashell11234455@gmail.com>
+S:	Maintained
+F:	board/sophgo/milkv_duo/
+F:	configs/milkv_duo_defconfig
+F:	doc/board/sophgo/milkv_duo.rst

board/sophgo/milkv_duo/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) 2024, Kongyang Liu <seashell11234455@gmail.com>
+
+obj-y := board.o

board/sophgo/milkv_duo/board.c

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2024, Kongyang Liu <seashell11234455@gmail.com>
+ */
+
+int board_init(void)
+{
+	return 0;
+}

configs/milkv_duo_defconfig

@@ -0,0 +1,23 @@
+CONFIG_RISCV=y
+CONFIG_SYS_MALLOC_LEN=0x820000
+CONFIG_SYS_MALLOC_F_LEN=0x2000
+CONFIG_NR_DRAM_BANKS=1
+CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
+CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x82300000
+CONFIG_DEFAULT_DEVICE_TREE="cv1800b-milkv-duo"
+CONFIG_IDENT_STRING="milkv_duo"
+CONFIG_SYS_LOAD_ADDR=0x80080000
+CONFIG_TARGET_MILKV_DUO=y
+CONFIG_ARCH_RV64I=y
+CONFIG_RISCV_SMODE=y
+CONFIG_FIT=y
+CONFIG_SUPPORT_RAW_INITRD=y
+CONFIG_HUSH_PARSER=y
+CONFIG_SYS_PROMPT="milkv_duo# "
+CONFIG_SYS_MAXARGS=64
+CONFIG_SYS_CBSIZE=512
+CONFIG_SYS_PBSIZE=544
+CONFIG_SYS_BOOTM_LEN=0x4000000
+CONFIG_ENV_OVERWRITE=y
+CONFIG_SYS_NS16550=y
+CONFIG_SYS_NS16550_MEM32=y

include/configs/milkv_duo.h

@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2024, Kongyang Liu <seashell11234455@gmail.com>
+ *
+ */
+
+#ifndef __CONFIG_H
+#define __CONFIG_H
+
+#define CFG_SYS_SDRAM_BASE         0x80000000
+
+#endif /* __CONFIG_H */