Using ubi as 0xdroid root filesystem on Devkit8000

Main idea

0xdroid has a lazy installer on BeagleBoard, I want a one on Devkit8k, so this is a roughly prototype and is not good enough as which oxlab has.

1. Copy Android root filesystem directory into Angstrom root filesystem directory in SD card.
2. Mount MTD devices  in Angstrom on Devkit80000
3. Copy Android root filesystem into mounted MTD device.
4. Changed  to using ubit device as rootfs in bootargs in uboot.

Prepare Installer

the installer has 2 part, one is uboot settings, and one is SD card data.

a. Created Angsrom Root Filesystem

a. 1 Formated SD card and create two partitions, first is FAT, second is EXT3, and types below.

user@host$ cd  ~/$(DEVKIT8k_BSPSRC)/linux/demo/angstrom
user@host$ cp uImage /media/FAT
user@host$ tar xjpvf Angstrom-Beagleboard-demo-image-glibc-ipk-2009.X-test-20090111-beagleboard.rootfs.tar.bz2 -C /media/EXT3
user@host$ mkdir /media/EXT3/home/root/rfs

a.2 Created a script which located in /media/EXT3/home/root/my_flash.sh, its content is below.

#!/bin/sh

flash_eraseall /dev/mtd4
ubiattach /dev/ubi_ctrl -m 4
ubimkvol /dev/ubi0 -N rootfs -s 100MiB
mount -t ubifs ubi0_0 /mnt
cp -a ~/rfs/* /mnt
umount /mnt

b. Copy Android root filesystem into SD card

The root file system is build before, if you want know how to get 0xdroid and how to build, please check http://gitorious.org/0xdroid/pages/Beagle-cupcake-0x1

user@host$ cd ~/$(OxDroidSRC)/out/target/product/beagleboard
user@host$ cp -a root/* /media/EXT3/home/root/rfs
user@host$ cp -a root/system/* /media/EXT3/home/root/rfs/system/

c. Copy Android uImage into SD card

user@host$ cp $(Oxkenerl)/arch/arm/boot/uImage /media/FAT/uImage_android

d. Booting Angstrom from SD card

Inserted SD card, and boot into uboot, then set boot args for running installer.
remember, in this step we will install mtd-utils, so you have to make sure that your network is available.

OMAP3 DevKit8000 # set installer 'set bootargs mem=128M console=ttyS2,115200n8 root=/dev/mmcblk0p2 rw noinitrd rootdelay=1;mmcinit;fatload mmc 0 80000000 uImage;bootm 80000000';save
OMAP3 DevKit8000 # run installer

e. Login as root

After booting successful, you can see Anstrom ask the login name, please use root to login.

f. Checks MTD devices exists

if the nand device nam is the same as kernel's , you can see the MTD devices informations by /proc/mtd

root@devkit8000$ cat /proc/mtd

g. Install mtd-utils

root@devkit8000$ opkg update
root@devkit8000$ opkg install mtd-utils

Using Installer

booted Installer(Angsrom) and login as root, then types

root@devkit8000$ cd ./my_flash.sh

Boot Oxdroid from nand

a. Flash uImage (the size of uImage should less than 2M bytes)

OMAP3 DevKit8000 # mmcinit
OMAP3 DevKit8000# fatload mmc 0:1 80000000 uImage_android
reading uImage 1991900 bytes read
OMAP3 DevKit8000 # nand unlock
device 0 whole chip nand_unlock: start: 00000000, length: 268435456!
NAND flash successfully unlocked
OMAP3 DevKit8000 # nand ecc sw
OMAP3 DevKit8000 # nand erase 280000 210000
NAND erase: device 0 offset 0x280000, size 0x200000
Erasing at 0x460000 -- 100% complete. OK
OMAP3 DevKit8000 # nand write.i 80000000 280000 $(filesize)
NAND write: device 0 offset 0x280000, size 0x200000
Writing data at 0x47f800 -- 100% complete.
2097152 bytes written: OK

b. Set nand bootargs and boot

OMAP3 DevKit8000 # set nandubi 'setenv bootargs console=ttyS2,115200n8 ubi.mtd=4 root=ubi0:rootfs rootfstype=ubifs init=/init;run nandboot'
OMAP3 DevKit8000 # setenv bootcmd 'nand read.i 80300000 280000 210000;bootm 80300000'
OMAP3 DevKit8000 # save
OMAP3 DevKit8000 # boot

Reference

1. UBI文件系统简介