khadas-vim4/khadas-vim1s: very early wip; meson-s4t7/legacy 5.4 Amlogic kernel

- only "boot from SD" supported right now
- building uboot with xPack riscv-none-embed-gcc **external** toolchain setup in hooks
- kvim4: very high kernel logging + systemd debug logging to console
- kvim4/kvim1s: add uEnv.txt and ROOT_FS_LABEL="ROOTFS" and Khadas-esque extlinux
- meson-s4t7: unify khadas-vim1s and khadas-vim4 u-boot building
- kernel .config:
  - s4t7: original Khadas vendor config
  - s4t7: CONFIG_BINFMT_MISC=y
  - s4t7: make NFS/sunrpc stuff =y
  - s4t7: enable USB wifi drivers from Armbian network_drivers
- firmware: at https://github.com/armbian/firmware/pull/56
- extlinux tricks require https://github.com/armbian/build/pull/5462
- status:
  - kvim1s: boots from SD and works as server/CLI
  - kvim4: kernel panic during systemd-udevd

config/boards/khadas-vim1s.wip

@@ -0,0 +1,32 @@
+# Amlogic S905Y4 4C 2GHz Cortex-A35 Mali-G31 MP2 2GB LPDDR4 16GB eMMC AP6256
+BOARD_NAME="Khadas VIM1S" # don't confuse with VIM1 (S905X)
+BOARDFAMILY="meson-s4t7"
+KERNEL_TARGET="legacy"
+BOARD_MAINTAINER="rpardini"
+SERIALCON="ttyS0"                  # for vendor kernel
+BOOT_FDT_FILE="amlogic/kvim1s.dtb" # vendor kernel dtb
+
+# Lets build uboot from source
+BOOTCONFIG="kvim1s_defconfig"
+KHADAS_BOARD_ID="kvim1s" # used to compile the fip blobs
+
+# Use extlinux and u-boot-menu extension
+SRC_CMDLINE="\\\${bootargs} \\\${partitiontype} \\\${boot_user_args}" # Khdas-specific uboot variables.... double-escaped, so they survive u-boot-menu's processing
+
+# Use uEnv.txt to conform to Khadas' documentation
+function pre_umount_final_image__khadas_s4t7_uenv() {
+	display_alert "$BOARD" "creating uEnv.txt; UUID=${ROOT_PART_UUID}" "info"
+	cat <<- UENV_KHADAS > "${SDCARD}/boot/uEnv.txt"
+		#############################DO NOT TOUCH THIS OPTION#############################
+		rootdev=root=UUID=${ROOT_PART_UUID}
+		partitiontype=partition_type=generic
+		#############################DO NOT TOUCH THIS OPTION#############################
+		fan_mode=auto
+		## Add user args here, spilt with space.
+		## e.g. Add bootargs 'test1=111 test2=222'
+		## boot_user_args=test1=111 test2=222
+		boot_user_args=
+	UENV_KHADAS
+
+	return 0
+}

config/boards/khadas-vim4.wip

@@ -0,0 +1,32 @@
+# Amlogic A311D2 8GB
+BOARD_NAME="Khadas VIM4"
+BOARDFAMILY="meson-s4t7"
+KERNEL_TARGET="legacy"
+BOARD_MAINTAINER="rpardini"
+SERIALCON="ttyS0"                 # for vendor kernel
+BOOT_FDT_FILE="amlogic/kvim4.dtb" # vendor kernel dtb; kvim4n.dtb for npu?
+
+# Lets build uboot from source
+BOOTCONFIG="kvim4_defconfig"
+KHADAS_BOARD_ID="kvim4" # used to compile the fip blobs
+
+# Use extlinux and u-boot-menu extension
+SRC_CMDLINE="loglevel=7 systemd.log_level=debug systemd.log_target=console systemd.journald.forward_to_console=1 \\\${bootargs} \\\${partitiontype} fan=\\\${fan_mode} \\\${boot_user_args} " # Khdas-specific uboot variables.... double-escaped, so they survive u-boot-menu's processing
+
+# Use uEnv.txt to conform to Khadas' documentation
+function pre_umount_final_image__khadas_s4t7_uenv() {
+	display_alert "$BOARD" "creating uEnv.txt; UUID=${ROOT_PART_UUID}" "info"
+	cat <<- UENV_KHADAS > "${SDCARD}/boot/uEnv.txt"
+		#############################DO NOT TOUCH THIS OPTION#############################
+		rootdev=root=UUID=${ROOT_PART_UUID}
+		partitiontype=partition_type=generic
+		#############################DO NOT TOUCH THIS OPTION#############################
+		fan_mode=auto
+		## Add user args here, spilt with space.
+		## e.g. Add bootargs 'test1=111 test2=222'
+		## boot_user_args=test1=111 test2=222
+		boot_user_args=
+	UENV_KHADAS
+
+	return 0
+}

config/sources/families/meson-s4t7.conf

@@ -0,0 +1,87 @@
+#
+# SPDX-License-Identifier: GPL-2.0
+# Copyright (c) 2023 Ricardo Pardini <ricardo@pardini.net>
+# This file is a part of the Armbian Build Framework https://github.com/armbian/build/
+#
+
+declare -g LINUXFAMILY="meson-s4t7"
+declare -g ARCH="arm64"
+declare -g ATF_COMPILE="no"
+
+# Use extlinux and u-boot-menu extension
+SRC_EXTLINUX="yes"
+EXTLINUX_UINITRD="no"          # Use normal initrd, not uInitrd; we're using vendor uboot and that does not support uInitrd
+enable_extension "u-boot-menu" # this generates the extlinux.conf
+
+# use Khadas-expected ROOTFS label for older uboot on SPI
+declare -g ROOT_FS_LABEL="ROOTFS"
+
+# Determine kernel
+case $BRANCH in
+
+	legacy)
+		declare -g KERNEL_MAJOR_MINOR="5.4"                           # Major and minor versions of this kernel. For mainline caching.
+		declare -g KERNELSOURCE="https://github.com/khadas/linux.git" # Khadas kernel
+		declare -g KERNELBRANCH="branch:khadas-vims-5.4.y"            # Branch or tag to build from. It should match MAJOR_MINOR
+		declare -g KERNELPATCHDIR='archive/meson-s4t7-5.4'
+		;;
+
+esac
+
+# Lets build uboot from source
+BOOTSOURCE="https://github.com/khadas/u-boot.git"
+BOOTBRANCH="branch:khadas-vims-v2019.01"
+UBOOT_TARGET_MAP=";;build/u-boot.bin.sd.bin.signed:u-boot.bin.sd.bin.signed"
+
+## funny enough, the uboot+fip blobs go in the same spot as normal meson64...
+function write_uboot_platform() {
+	dd if="$1/u-boot.bin.sd.bin.signed" of="$2" conv=fsync,notrunc bs=442 count=1       #> /dev/null 2>&1
+	dd if="$1/u-boot.bin.sd.bin.signed" of="$2" conv=fsync,notrunc bs=512 skip=1 seek=1 #> /dev/null 2>&1
+}
+
+# We'll need xxd to build the fip blobs
+function add_host_dependencies__khadas_fips_needs_xxd() {
+	display_alert "Adding xxd to host dependencies" "for khadas bootloader compile" "debug"
+	declare -g EXTRA_BUILD_DEPS="${EXTRA_BUILD_DEPS} xxd"
+}
+
+# To be able to build the fip blobs, we need a riscv toolchain.
+function pre_config_uboot_target__prepare_riscv_toolchain() {
+	display_alert "$BOARD" "preparing riscv toolchain for bootloader fip" "info"
+
+	declare tos="x64"
+	[[ "${HOSTARCH}" == "arm64" ]] && tos="arm64"
+	[[ "${HOSTARCH}" == "armhf" ]] && tos="arm"
+	declare tversion="8.3.0-1.2"
+	declare tbasedir="${SRC}/cache/toolchain"
+	declare tdir="${tbasedir}/xpack-riscv-none-embed-gcc-${tversion}"
+	declare tfile="xpack-riscv-none-embed-gcc-${tversion}-linux-${tos}.tar.gz"
+	declare turl="https://github.com/xpack-dev-tools/riscv-none-embed-gcc-xpack/releases/download/v${tversion}/${tfile}"
+
+	mkdir -p "${tbasedir}"
+
+	if [[ ! -d "${tdir}" ]]; then
+		run_host_command_logged wget --progress=dot:giga -O "${tbasedir}/${tfile}" "${turl}"
+		run_host_command_logged tar -C "${tbasedir}" -xzf "${tbasedir}/${tfile}"
+		run_host_command_logged rm -fv "${tbasedir}/${tfile}"
+	fi
+
+	# Symlinks are not enough: riscv-none-embed-ld: cannot find -lgcc, So we need to add the toolchain to the PATH
+	declare -g -r PRE_TOOLCHAIN_PATH="${PATH}"
+	export PATH="${tdir}/bin:${PATH}"
+}
+
+function post_config_uboot_target__downgrade_errors_to_warnings() {
+	uboot_cflags_array+=("-Wno-error=array-bounds")
+	return 0
+}
+
+# Invoke fip build script after the u-boot target
+function post_uboot_custom_postprocess__build_fip() {
+	: "${uboot_work_dir:?uboot_work_dir not set}"
+	: "${KHADAS_BOARD_ID:?KHADAS_BOARD_ID not set}"
+	display_alert "$BOARD" "building fip" "info"
+	cd "${uboot_work_dir}" || exit_with_error "cray-cray about ${uboot_work_dir}"
+	run_host_command_logged bash fip/mk_script.sh "${KHADAS_BOARD_ID}" "${uboot_work_dir}"
+	return 0
+}