configs/stm32f769_disco_sd_defconfig: new defconfig

Board support package includes the following components:
- mainline Linux kernel 5.15.108
- mainline U-Boot 2023.04
- default packages from buildroot

Note: There is a problem in u-boot display management. It should display
the ST microelectronics logo but "noise" is displayed (like when running
the command dd if=/dev/urandom of=/dev/fb0 in Linux). I also tried to
change version (even the first version in which this feature was
introduced), but without success. Despite this I decided not to disable
the video management configuration to remind us that it needs to be
fixed :).

Cc: Giulio Benetti <giulio.benetti@benettiengineering.com>
Link: https://www.st.com/en/evaluation-tools/32f769idiscovery.html
Signed-off-by: Dario Binacchi <dario.binacchi@amarulasolutions.com>
Reviewed-by: Giulio Benetti <giulio.benetti@benettiengineering.com>
Signed-off-by: Yann E. MORIN <yann.morin.1998@free.fr>

DEVELOPERS

@@ -702,8 +702,10 @@ F:	package/xinetd/
 
 N:	Dario Binacchi <dario.binacchi@amarulasolutions.com>
 F:	board/bsh/
+F:	board/stmicroelectronics/stm32f769-disco/
 F:	configs/imx8mn_bsh_smm_s2_defconfig
 F:	configs/imx8mn_bsh_smm_s2_pro_defconfig
+F:	configs/stm32f769_disco_sd_defconfig
 F:	package/sscep/
 F:	package/uuu/
 

board/stmicroelectronics/stm32f769-disco/extlinux.conf

@@ -0,0 +1,4 @@
+label stm32f769-disco-buildroot
+  kernel /zImage
+  devicetree /stm32f769-disco.dtb
+  append console=ttySTM0,115200 root=/dev/mmcblk0p2 rw rootfstype=ext2 rootwait earlyprintk consoleblank=0 ignore_loglevel

board/stmicroelectronics/stm32f769-disco/flash_sd.sh

@@ -0,0 +1,18 @@
+#!/bin/bash
+
+OUTPUT_DIR=$1
+
+if ! test -d "${OUTPUT_DIR}" ; then
+    echo "ERROR: no output directory specified."
+    echo "Usage: $0 OUTPUT_DIR"
+    exit 1
+fi
+
+"${OUTPUT_DIR}"/host/bin/openocd -f board/stm32f769i-disco.cfg \
+  -c "init" \
+  -c "reset init" \
+  -c "flash probe 0" \
+  -c "flash info 0" \
+  -c "flash write_image erase ${OUTPUT_DIR}/images/u-boot.bin 0x08000000" \
+  -c "reset run" \
+  -c "shutdown"

board/stmicroelectronics/stm32f769-disco/genimage.cfg

@@ -0,0 +1,27 @@
+image boot.vfat {
+	vfat {
+		files = {
+			"zImage",
+			"stm32f769-disco.dtb",
+			"extlinux"
+		}
+	}
+
+	size = 16M
+}
+
+image sdcard.img {
+	hdimage {
+	}
+
+	partition u-boot {
+		partition-type = 0xC
+		image = "boot.vfat"
+	}
+
+	partition rootfs {
+		partition-type = 0x83
+		image = "rootfs.ext2"
+		size = 32M
+	}
+}

board/stmicroelectronics/stm32f769-disco/linux-sd.fragment

@@ -0,0 +1 @@
+# CONFIG_XIP_KERNEL is not set

board/stmicroelectronics/stm32f769-disco/post-build.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+BOARD_DIR="$(dirname "$0")"
+
+# Kernel is built without devpts support
+sed -i '/^devpts/d' "${TARGET_DIR}"/etc/fstab
+
+install -m 0644 -D "${BOARD_DIR}"/extlinux.conf "${BINARIES_DIR}"/extlinux/extlinux.conf

board/stmicroelectronics/stm32f769-disco/readme.txt

@@ -0,0 +1,32 @@
+STM32F769 Discovery
+===================
+
+This tutorial describes how to use the predefined Buildroot
+configuration for the STM32F769 Discovery evaluation platform.
+
+Building
+--------
+
+  make stm32f769_disco_sd_defconfig
+  make
+
+Flashing
+--------
+
+  ./board/stmicroelectronics/stm32f769-disco/flash_sd.sh output/
+
+It will flash the U-boot bootloader.
+
+Creating SD card
+----------------
+
+Buildroot prepares an"sdcard.img" image in the output/images/ directory,
+ready to be dumped on a SD card. Launch the following command as root:
+
+  dd if=output/images/sdcard.img of=/dev/<your-sd-device>
+
+*** WARNING! This will destroy all the card content. Use with care! ***
+
+For details about the medium image layout and its content, see the
+definition in board/stmicroelectronics/stm32f769-disco/genimage.cfg.
+

configs/stm32f769_disco_sd_defconfig

@@ -0,0 +1,30 @@
+BR2_arm=y
+BR2_cortex_m7=y
+BR2_PACKAGE_HOST_LINUX_HEADERS_CUSTOM_5_15=y
+BR2_ROOTFS_POST_BUILD_SCRIPT="board/stmicroelectronics/stm32f769-disco/post-build.sh"
+BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
+BR2_ROOTFS_POST_SCRIPT_ARGS="-c board/stmicroelectronics/stm32f769-disco/genimage.cfg"
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION=y
+BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="5.15.108"
+BR2_LINUX_KERNEL_DEFCONFIG="stm32"
+BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="$(LINUX_DIR)/arch/arm/configs/dram_0xc0000000.config board/stmicroelectronics/stm32f769-disco/linux-sd.fragment"
+BR2_LINUX_KERNEL_IMAGE_TARGET_CUSTOM=y
+BR2_LINUX_KERNEL_IMAGE_TARGET_NAME="zImage"
+BR2_LINUX_KERNEL_DTS_SUPPORT=y
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="stm32f769-disco"
+BR2_PACKAGE_BUSYBOX_CONFIG="package/busybox/busybox-minimal.config"
+# BR2_PACKAGE_IFUPDOWN_SCRIPTS is not set
+BR2_TARGET_ROOTFS_EXT2=y
+BR2_TARGET_ROOTFS_EXT2_SIZE="32M"
+# BR2_TARGET_ROOTFS_TAR is not set
+BR2_TARGET_UBOOT=y
+BR2_TARGET_UBOOT_BUILD_SYSTEM_KCONFIG=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION=y
+BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2023.04"
+BR2_TARGET_UBOOT_BOARD_DEFCONFIG="stm32f769-disco"
+BR2_TARGET_UBOOT_NEEDS_OPENSSL=y
+BR2_PACKAGE_HOST_DOSFSTOOLS=y
+BR2_PACKAGE_HOST_GENIMAGE=y
+BR2_PACKAGE_HOST_MTOOLS=y
+BR2_PACKAGE_HOST_OPENOCD=y