ath25: add back target support

Discussion on the mailing list reveals that this target has active
users. As we are finally able to upgrade this target to kernel 5.4,
add it back to master.

This reverts commit 7d29a5571403 ("ath25: drop target") and
immediately moves the relevant files to 5.4, without touching
the content.

Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>

1 files changed, 76 insertions, 0 deletions

diff --git a/target/linux/ath25/base-files/lib/upgrade/platform.sh b/target/linux/ath25/base-files/lib/upgrade/platform.sh
new file mode 100644
index 0000000000..778bbf5a39
--- /dev/null
+++ b/target/linux/ath25/base-files/lib/upgrade/platform.sh
@@ -0,0 +1,76 @@
+CI_BLKSZ=65536
+CI_LDADR=0x80041000
+
+platform_find_partitions() {
+	local first dev size erasesize name
+	while read dev size erasesize name; do
+		name=${name#'"'}; name=${name%'"'}
+		case "$name" in
+			vmlinux.bin.l7|kernel|linux|rootfs)
+				if [ -z "$first" ]; then
+					first="$name"
+				else
+					echo "$erasesize:$first:$name"
+					break
+				fi
+			;;
+		esac
+	done < /proc/mtd
+}
+
+platform_find_kernelpart() {
+	local part
+	for part in "${1%:*}" "${1#*:}"; do
+		case "$part" in
+			vmlinux.bin.l7|kernel|linux)
+				echo "$part"
+				break
+			;;
+		esac
+	done
+}
+
+platform_check_image() {
+	[ "$#" -gt 1 ] && return 1
+
+	case "$(get_magic_word "$1")" in
+		# Combined Image
+		4349)
+			local md5_img=$(dd if="$1" bs=2 skip=9 count=16 2>/dev/null)
+			local md5_chk=$(dd if="$1" bs=$CI_BLKSZ skip=1 2>/dev/null | md5sum -); md5_chk="${md5_chk%% *}"
+
+			if [ -n "$md5_img" -a -n "$md5_chk" ] && [ "$md5_img" = "$md5_chk" ]; then
+				return 0
+			else
+				echo "Invalid image. Contents do not match checksum (image:$md5_img calculated:$md5_chk)"
+				return 1
+			fi
+		;;
+		*)
+			echo "Invalid image. Use combined .img files on this platform"
+			return 1
+		;;
+	esac
+}
+
+platform_do_upgrade() {
+	local partitions=$(platform_find_partitions)
+	local kernelpart=$(platform_find_kernelpart "${partitions#*:}")
+	local erase_size=$((0x${partitions%%:*})); partitions="${partitions#*:}"
+	local kern_length=0x$(dd if="$1" bs=2 skip=1 count=4 2>/dev/null)
+	local kern_blocks=$(($kern_length / $CI_BLKSZ))
+	local root_blocks=$((0x$(dd if="$1" bs=2 skip=5 count=4 2>/dev/null) / $CI_BLKSZ))
+
+	if [ -n "$partitions" ] && [ -n "$kernelpart" ] && \
+	   [ ${kern_blocks:-0} -gt 0 ] && \
+	   [ ${root_blocks:-0} -gt ${kern_blocks:-0} ] && \
+	   [ ${erase_size:-0} -gt 0 ];
+	then
+		local append=""
+		[ -f "$UPGRADE_BACKUP" ] && append="-j $UPGRADE_BACKUP"
+
+		( dd if="$1" bs=$CI_BLKSZ skip=1 count=$kern_blocks 2>/dev/null; \
+		  dd if="$1" bs=$CI_BLKSZ skip=$((1+$kern_blocks)) count=$root_blocks 2>/dev/null ) | \
+			mtd -r $append -F$kernelpart:$kern_length:$CI_LDADR,rootfs write - $partitions
+	fi
+}