riscv: t-head: licheepi4a: initial support added

Add support for Sipeed's Lichee Pi 4A board which based on T-HEAD's
TH1520 SoC, only minimal device tree and serial console are enabled,
so it's capable of chain booting from T-HEAD's vendor u-boot.

Reviewed-by: Wei Fu <wefu@redhat.com>
Signed-off-by: Yixun Lan <dlan@gentoo.org>

arch/riscv/Kconfig

@@ -27,6 +27,10 @@ config TARGET_SIFIVE_UNMATCHED
 config TARGET_STARFIVE_VISIONFIVE2
 	bool "Support StarFive VisionFive2 Board"
 
+config TARGET_TH1520_LPI4A
+	bool "Support Sipeed's TH1520 Lichee PI 4A Board"
+	select SYS_CACHE_SHIFT_6
+
 config TARGET_SIPEED_MAIX
 	bool "Support Sipeed Maix Board"
 	select SYS_CACHE_SHIFT_6
@@ -66,6 +70,7 @@ source "board/emulation/qemu-riscv/Kconfig"
 source "board/microchip/mpfs_icicle/Kconfig"
 source "board/sifive/unleashed/Kconfig"
 source "board/sifive/unmatched/Kconfig"
+source "board/thead/th1520_lpi4a/Kconfig"
 source "board/openpiton/riscv64/Kconfig"
 source "board/sipeed/maix/Kconfig"
 source "board/starfive/visionfive2/Kconfig"

board/thead/th1520_lpi4a/Kconfig

@@ -0,0 +1,42 @@
+if TARGET_TH1520_LPI4A
+
+config ARCH_THEAD
+	bool
+	default y
+
+config SYS_BOARD
+	default "th1520_lpi4a"
+
+config SYS_VENDOR
+	default "thead"
+
+config SYS_CPU
+	default "generic"
+
+config SYS_CONFIG_NAME
+	default "th1520_lpi4a"
+
+config TEXT_BASE
+	default 0x01b00000 if SPL
+	default 0x01c00000 if !RISCV_SMODE
+	default 0x01c00000 if RISCV_SMODE
+
+config SPL_TEXT_BASE
+	default 0x08000000
+
+config SPL_OPENSBI_LOAD_ADDR
+	default 0x80000000
+
+config BOARD_SPECIFIC_OPTIONS
+	def_bool y
+	select ARCH_EARLY_INIT_R
+	imply CPU
+	imply CPU_RISCV
+	imply RISCV_TIMER if RISCV_SMODE
+	imply CMD_CPU
+	imply SMP
+	imply SUPPORT_OF_CONTROL
+	imply OF_CONTROL
+	imply OF_REAL
+
+endif

board/thead/th1520_lpi4a/MAINTAINERS

@@ -0,0 +1,7 @@
+Lichee PI 4A
+M:	Wei Fu <wefu@redhat.com>
+M:	Yixun Lan <dlan@gentoo.org>
+S:	Maintained
+F:	board/thead/th1520_lpi4a/
+F:	configs/th1520_lpi4a_defconfig
+F:	doc/board/thead/lpi4a.rst

board/thead/th1520_lpi4a/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) 2023, Yixun Lan <dlan@gentoo.org>
+
+obj-y += board.o

board/thead/th1520_lpi4a/board.c

@@ -0,0 +1,15 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2023, Yixun Lan <dlan@gentoo.org>
+ *
+ */
+
+#include <common.h>
+#include <cpu_func.h>
+
+int board_init(void)
+{
+	enable_caches();
+
+	return 0;
+}

include/configs/th1520_lpi4a.h

@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (c) 2023 Yixun Lan <dlan@gentoo.org>
+ *
+ */
+
+#ifndef __TH1520_LPI4A_H
+#define __TH1520_LPI4A_H
+
+#include <linux/sizes.h>
+
+#define CFG_SYS_SDRAM_BASE		0x00000000
+
+#define UART_BASE	0xffe7014000
+#define UART_REG_WIDTH  32
+
+/* Environment options */
+
+#define CFG_EXTRA_ENV_SETTINGS \
+	"PS1=[LPi4A]# \0"
+
+#endif /* __TH1520_LPI4A_H */