board: stm32: add stm32h747-discovery board support

The board includes an STM32H747XI SoC with the following resources:
 - 2 Mbytes Flash
 - 1 Mbyte SRAM
 - LCD-TFT controller
 - MIPI-DSI interface
 - FD-CAN
 - USB 2.0 high-speed/full-speed
 - Ethernet MAC
 - camera interface

Detailed information can be found at:
https://www.st.com/en/evaluation-tools/stm32h747i-disco.html

Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>

arch/arm/mach-stm32/stm32h7/Kconfig

@@ -6,11 +6,15 @@ config TARGET_STM32H743_DISCO
 config TARGET_STM32H743_EVAL
 	bool "STM32H743 Evaluation board"
 
+config TARGET_STM32H747_DISCO
+	bool "STM32H747 Discovery board"
+
 config TARGET_STM32H750_ART_PI
 	bool "STM32H750 ART Pi board"
 
 source "board/st/stm32h743-eval/Kconfig"
 source "board/st/stm32h743-disco/Kconfig"
+source "board/st/stm32h747-disco/Kconfig"
 source "board/st/stm32h750-art-pi/Kconfig"
 
 endif

board/st/stm32h747-disco/Kconfig

@@ -0,0 +1,15 @@
+if TARGET_STM32H747_DISCO
+
+config SYS_BOARD
+	default "stm32h747-disco"
+
+config SYS_VENDOR
+	default "st"
+
+config SYS_SOC
+	default "stm32h7"
+
+config SYS_CONFIG_NAME
+	default "stm32h747-disco"
+
+endif

board/st/stm32h747-disco/MAINTAINERS

@@ -0,0 +1,7 @@
+STM32H747 DISCOVERY BOARD
+M:	Dario Binacchi <dario.binacchi@amarulasolutions.com>
+S:	Maintained
+F:	board/st/stm32h747-disco
+F:	include/configs/stm32h747-disco.h
+F:	configs/stm32h747-disco_defconfig
+F:	arch/arm/dts/stm32h747*

board/st/stm32h747-disco/Makefile

@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) 2025 Dario Binacchi <dario.binacchi@amarulasolutions.com>
+#
+
+obj-y	:= stm32h747-disco.o

board/st/stm32h747-disco/stm32h747-disco.c

@@ -0,0 +1,42 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * stm32h747i-disco support
+ *
+ * Copyright (C) 2025 Dario Binacchi <dario.binacchi@amarulasolutions.com>
+ */
+
+#include <dm.h>
+#include <init.h>
+#include <log.h>
+#include <asm/global_data.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int dram_init(void)
+{
+	struct udevice *dev;
+	int ret;
+
+	ret = uclass_get_device(UCLASS_RAM, 0, &dev);
+	if (ret) {
+		debug("DRAM init failed: %d\n", ret);
+		return ret;
+	}
+
+	if (fdtdec_setup_mem_size_base() != 0)
+		ret = -EINVAL;
+
+	return ret;
+}
+
+int dram_init_banksize(void)
+{
+	fdtdec_setup_memory_banksize();
+
+	return 0;
+}
+
+int board_init(void)
+{
+	return 0;
+}

configs/stm32h747-disco_defconfig

@@ -0,0 +1,35 @@
+CONFIG_ARM=y
+CONFIG_ARCH_STM32=y
+CONFIG_TEXT_BASE=0x08000000
+CONFIG_SYS_MALLOC_LEN=0x100000
+CONFIG_NR_DRAM_BANKS=1
+CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
+CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x24040000
+CONFIG_ENV_SIZE=0x2000
+CONFIG_DEFAULT_DEVICE_TREE="st/stm32h747i-disco"
+CONFIG_OF_LIBFDT_OVERLAY=y
+CONFIG_SYS_LOAD_ADDR=0xd0400000
+CONFIG_STM32H7=y
+CONFIG_TARGET_STM32H747_DISCO=y
+CONFIG_DISTRO_DEFAULTS=y
+CONFIG_BOOTDELAY=3
+CONFIG_AUTOBOOT_KEYED=y
+CONFIG_AUTOBOOT_PROMPT="Hit SPACE in %d seconds to stop autoboot.\n"
+CONFIG_AUTOBOOT_STOP_STR=" "
+CONFIG_DEFAULT_FDT_FILE="stm32h747i-disco"
+CONFIG_SYS_CBSIZE=256
+CONFIG_SYS_PBSIZE=282
+# CONFIG_DISPLAY_CPUINFO is not set
+CONFIG_SYS_PROMPT="U-Boot > "
+CONFIG_CMD_GPT=y
+CONFIG_CMD_MMC=y
+# CONFIG_CMD_SETEXPR is not set
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_TIMER=y
+CONFIG_CMD_EXT4_WRITE=y
+# CONFIG_ISO_PARTITION is not set
+CONFIG_OF_CONTROL=y
+CONFIG_SYS_RELOC_GD_ENV_ADDR=y
+CONFIG_NO_NET=y
+CONFIG_STM32_SDMMC2=y
+# CONFIG_PINCTRL_FULL is not set

drivers/clk/stm32/clk-stm32h7.c

@@ -114,6 +114,7 @@
 #define		QSPISRC_PER_CK		3
 
 #define PWR_CR3				0x0c
+#define PWR_CR3_LDOEN			BIT(1)
 #define PWR_CR3_SCUEN			BIT(2)
 #define PWR_D3CR			0x18
 #define PWR_D3CR_VOS_MASK		GENMASK(15, 14)
@@ -375,7 +376,11 @@ int configure_clocks(struct udevice *dev)
 	clrsetbits_le32(pwr_base + PWR_D3CR, PWR_D3CR_VOS_MASK,
 			VOS_SCALE_1 << PWR_D3CR_VOS_SHIFT);
 	/* Lock supply configuration update */
+#if IS_ENABLED(CONFIG_TARGET_STM32H747_DISCO)
+	clrbits_le32(pwr_base + PWR_CR3, PWR_CR3_LDOEN);
+#else
 	clrbits_le32(pwr_base + PWR_CR3, PWR_CR3_SCUEN);
+#endif
 	while (!(readl(pwr_base + PWR_D3CR) & PWR_D3CR_VOSREADY))
 		;
 

include/configs/stm32h747-disco.h

@@ -0,0 +1,32 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2025 Dario Binacchi <dario.binacchi@amarulasolutions.com>
+ */
+
+#ifndef __CONFIG_H
+#define __CONFIG_H
+
+#include <config.h>
+#include <linux/sizes.h>
+
+/* For booting Linux, use the first 16MB of memory */
+#define CFG_SYS_BOOTMAPSZ		SZ_16M
+
+#define CFG_SYS_FLASH_BASE		0x08000000
+
+#define CFG_SYS_HZ_CLOCK		1000000
+
+#define BOOT_TARGET_DEVICES(func) \
+	func(MMC, mmc, 0)
+
+#include <config_distro_bootcmd.h>
+#define CFG_EXTRA_ENV_SETTINGS				\
+			"kernel_addr_r=0xD0008000\0"		\
+			"fdtfile=stm32h747i-disco.dtb\0"	\
+			"fdt_addr_r=0xD0408000\0"		\
+			"scriptaddr=0xD0418000\0"		\
+			"pxefile_addr_r=0xD0428000\0" \
+			"ramdisk_addr_r=0xD0438000\0"		\
+			BOOTENV
+
+#endif /* __CONFIG_H */