gemini: Generate harddisk image for DNS-313

This makes OpenWrt build an Ext2+Ext4 partitioned image
for the D-Link DNS-313 with two blank partitions, a boot
partition on /dev/sda3 and a rootfs partition on
/dev/sda4.

This uses the methods already used in apm821xx including
the tricks to convert the generated Ext2 filesystem
partition to version 1 so that the firmware bootloader
will properly recognize it.

We patch a bit around the build files to make sure we
get the rootfs size set and that genext2fs is properly
built.

Tested on the D-Link DNS-313.

Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
[Fixing and tricksing]
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 28 insertions, 0 deletions

diff --git a/target/linux/gemini/image/dns313_gen_hdd_img.sh b/target/linux/gemini/image/dns313_gen_hdd_img.sh
new file mode 100755
index 0000000000..1eb2c7c575
--- /dev/null
+++ b/target/linux/gemini/image/dns313_gen_hdd_img.sh
@@ -0,0 +1,28 @@
+#!/usr/bin/env bash
+
+set -x
+[ $# -eq 5 ] || {
+	echo "SYNTAX: $0 <file> <bootfs image> <rootfs image> <bootfs size> <rootfs size>"
+	exit 1
+}
+
+OUTPUT="$1"
+BOOTFS="$2"
+ROOTFS="$3"
+BOOTFSSIZE="$4"
+ROOTFSSIZE="$5"
+
+head=4
+sect=63
+
+# Create two empty partitions followed by the boot partition with
+# the ./boot/zImage and then the rootfs partition.
+set `ptgen -o $OUTPUT -h $head -s $sect -t 83 -n -p 0 -p 0 -p ${BOOTFSSIZE}M -p ${ROOTFSSIZE}M`
+
+BOOTOFFSET="$(($1 / 512))"
+BOOTSIZE="$(($2 / 512))"
+ROOTFSOFFSET="$(($3 / 512))"
+ROOTFSSIZE="$(($4 / 512))"
+
+dd bs=512 if="$BOOTFS" of="$OUTPUT" seek="$BOOTOFFSET" conv=notrunc
+dd bs=512 if="$ROOTFS" of="$OUTPUT" seek="$ROOTFSOFFSET" conv=notrunc