Boot from USB using u-boot

Note: This instruction apply and booting only to TV with firmwares listed below!

T-CHL5DEUC, T-CHL5DAUC, T-CHE6AUSC, T-CHE7AUSC, T-CHEAUSC, T-CHL7DAUC, T-CHL7DEUC, T-CHU7DAUC, T-CHU7DEUC

This is for advanced users and developers only.

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Requirements:

• Serial connection
• Usb disk drive or pen drive (at least 256MB)
• TFTP server outside TV on some host in case using pen drive or optionally in case disk drive
• Regular Linux based system to prepare usb disk/pen drive
• Builded rootfs image

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Follow steps:

Build OE kernel and rootfs

• Prebuilded images you can find from here: http://download.samygo.tv/SamyGO%20Open%20Embedded/binaries/ .

Or you can build your self from recent repository:

• Build rootfs image using SamyGO OE Framework.

Builded rootfs image is located in build-samygo/tmp/deploy/images directory. File name looks like externalboot-base-rootfs-ssdtv-xxxxxxx.tar.gz.

Prepare USB disk

• Partition usb disk/pen drive.

Partition drive using fdisk or other tool.

First partition FAT type. It will be usefull or needed if you don't have network on tv. Second partition set as Linux type.

Format first partition with mtools or other tool as VFAT type filesystem. Format second partition with ext2fsprogs as ext3.

• Unpack rootfs image to linux partition on usb disk/pen drive.

Unpack image to second partition with root rights.

• Download firmware upgrade file (e.g T-CHL7DEUC.exe for B65x-B75x) and place as is on /home/root

• Download LaunchCLManager.zip and place as is on /home/root

TFTP server for kernel load

• Put kernel image to TFTP service directory. (or /tftpboot directory. on my NAS it is on /opt/tftpboot)

Note: Do this only if you want faster kernel load image.

• Find proper kernel image in build-samygo/tmp/deploy/images.

It's like: uImage-2.6.18.8-r0-ssdtv.multi-config-multi-config-bXXX.bin.

For firmwares:

T-CHE7AUSC, T-CHEAUSC, T-CHL7DAUC, T-CHL7DEUC, T-CHU7DAUC, T-CHU7DEUC - use b650

T-CHE6AUSC - use b6000

T-CHL5DEUC, T-CHL5DAUC - use b550

• Copy and rename it to uImage into root directory of TFTP service or on FAT partition if you are not using TFTP way.

• Enable serial debug console.

• Enter u-boot prompt shell.

• Set variables and execute commands in u-boot shell to boot linux kernel.

Booting TV

You can boot kernel and rootfs from any source (USB, TFTP or NFS) Here few scenario:

TFTP

Set network variables first:

setenv ipaddr 192.168.1.100;setenv gatewayip 192.168.1.1;setenv serverip 192.168.1.200

where first IP is TV, second gateway is not important in this case, third is address of TFTP server.

Boot linux kernel over TFTP and rootfs from USB ext3 partition:

setenv bootargs root=/dev/sda2 console=ttyS1;tftp;bootm

USB

Boot linux kernel from USB FAT partition, rootfs from USB ext3 partition:

setenv bootargs root=/dev/sda2 rootdelay=1 console=ttyS1;usb start;fatload usb 0 61000000 uImage;bootm

where /dev/sda2 is linux rootfs. uImage can be taken from TV kernel partition (see Dumping and Flashing images by hand) but it must have added uboot header.

mkimage -A arm -O linux -T kernel -a 0x60008000 -e 0x60008000 -C none -n "Original Samsung Kernel" -d ./bml5.img uImage

Without header u-boot will trigger error: Bad Magic Number

NFS

If you have NFS server on your home network working, you can boot file system for TV (rootfs) and kernel from OE over NFS!

Prepare rootfs and kernel

• #Prepare_USB_disk, or you can simply extract rootfs.tar.gz from OE on your NAS directory:

(i use /mnt/disk1/TV_rootfs for filesystem)

cd /mnt/disk1/TV_rootfs
cp /<path to>/rootfs.tar.gz /mnt/disk1/TV_rootfs
tar xzf rootfs.tar.gz

• Copy kernel file (uImage) to /mnt/disk1/TV_rootfs

 cp /<path to>/uImage /mnt/disk1/TV_rootfs

• Edit exports to enable your rootfs and uImage on NFS

If you use filesystem on USB, attached to NAS:

root@LS-GL984:~# cat /etc/exports
/mnt/usbdisk3 192.168.1.100/255.255.255.0(rw,async,all_squash,anonuid=99,anongid=99,no_subtree_check)

If you use filesystem on NAS directory:

root@LS-GL984:~# cat /etc/exports
/mnt/disk1/TV_rootfs 192.168.1.100/255.255.255.0(rw,async,all_squash,anonuid=99,anongid=99,no_subtree_check)

where 192.168.1.100 is my TV IP. 255.255.255.0 is submask, /mnt/usbdisk3 is my USB with TVs file system, /mnt/disk1/TV_rootfs - path to rootfs and kernel on NAS directory.

Boot kernel and rootfs over network

• Enter to u-boot promt.

• set network variables to load kernel

setenv ipaddr 192.168.1.100;setenv gatewayip 192.168.1.1;setenv serverip 192.168.1.200

• set network variables to load rootfs

setenv bootargs root=/dev/nfs rw nfsroot=192.168.1.200:/mnt/usbdisk3 rootpath=/home/root ip=192.168.1.102:192.168.1.200:192.168.1.1:255.255.255.0:LS-GL984:eth0:off console=ttyS1

Now you have to boot kernel. Choose method you prefer (use NFS or TFTP)

• load kernel over NFS and start booting TV

nfs 0x61000000 192.168.1.200:/disk1/TV_rootfs/uImage;bootm

• load kernel over TFTP and start booting TV

tftp;bootm

P.s. structure of commandline should for NFS should be:

setenv bootargs root=/dev/nfs rw nfsroot=${serverip} rootpath=${rootpath} ip=${ipaddr}:${serverip}:${gatewayip}:${netmask}:${hostname}:eth0:off  console=ttyS1

Where rootpath of OE kernel is /home/root

Starting TV software

After boot system, login over serial console as root and execute followed commands:

• Install Samsung original software:

samsung-install.sh

Choose your firmware version:

root@localhost:~# samsung-install.sh

--- Installer of Original Samsung Software ---
--- SamyGO  http://samygo.sourceforge.net  ---


Select proper firmware for your TV:

1. T-CHE6AUSC
2. T-CHE7AUSC
3. T-CHEAUSC
4. T-CHL5DAUC
5. T-CHL5DEUC
6. T-CHL7DAUC
7. T-CHL7DEUC
8. T-CHU7DAUC
9. T-CHU7DEUC

Choice:

Wait while TV installs firmware. It is quite long process, be patient.

• Start Samsung original software:

samsung-start.sh

Done!

NB! Kernel from OE does not support NAND writing and it does not help to restore bricked device.

--Juzis28 13:57, 1 December 2010 (UTC)