Hacking devices can/will void your warranty and can turn your expensive consumer electronics into worthless trash if you don't know what you're doing. This blog is for information purposes only, and if you try to hack into your own consumer electronics, you do so at your own risk. The device I'm currently hacking is the Canon SX10 IS camera.

Friday, June 12, 2009

New Buildroot / Toolchain

I have used the linux 2.6.12.6-VENUS code published by iomega https://iomega-eu-en.custhelp.com/cgi-bin/iomega_eu_en.cfg/php/enduser/std_adp.php?p_faqid=21578 and the uClibc from the raidsonic http://www.raidsonic.de/de/data/driver/firmware/IB-MP3010HW/Sources_RaidSonic.rar which is also an RTD player like the SPP.

Using these two sources has enabled me to make library files that are closer to what is on the Iomega device. Without Iomega's version of the uClibc, it'll take more work to get it to be exact.

These instructions are what is necessary to set up a complete cross compiling environment and using the buildroot to make your own toolchain. You can use the toolchain on the iomega device, or just use the buildroot to build whatever files you need.

All of the links to the new stuff will be at the bottom of this post. For those who want to try to recreate and maybe fix anything I did wrong, here's a set by step.

Prerequisites:
VMWare Player (I'm using version 2.5). It's free, but requires registration to download from http://vmware.com/products/player/
VMX Builder (free, google it. It is used to make the configuration files for vmware)
Ubuntu 8.04.1 (free, google it)

step 1, installing Ubuntu
Setup new virtual machine using VMX Builder.
Set at least a 20 GB hard drive, CD Player pointing to the Ubuntu 8.04.1 ISO, ethernet (amdlance, NAT)
and a reasonable amount of memory (1 Gig works well). Make sure target platform is Player 2.x, guest is Linux, and OS is Ubuntu.
Boot the virtual machine
Select to install Ubuntu.
Ubuntu will boot and if you don't see the Install screen within a few minutes, you probably didn't give it enough memory.
Login name: developer
Login password: root
Wait...twiddle thumbs...power nap
After reboot, click on the CD-ROM button to "take the CD out of the drive".
It will finally boot to the login screen. Login with your username and password you selected.
Select System>Preferences>Screen Resolution. You're going to need to increase it to at least 1024 x 768 to even make it useable.
This virtual Machine will take about 2 1/2 GB on your drive at this point.

step 2, Preparing the machine for development. Much of this comes from the gumstix wiki.
Select Applications>Accessories>Terminal
Confirm that you can connect to the network. ping your gateway, and ping www.google.com. Fix any network problems before continuing.
You should be able to run the update.

sudo apt-get update
(you will need to provide your password)

sudo apt-get install build-essential libncurses-dev bison flex texinfo zlib1g-dev gettext autoconf subversion wget samba git git-core

sudo dpkg-reconfigure dash
select no. This will uninstall dash.

now to get the buildroot source:

git clone git://opensphd.git.sourceforge.net/gitroot/opensphd/opensphd opensphd

(note: Edited 12/12/2009. On 8/25/2009, sourceforge modified the git repository capabilities which required an adjustment to the above git command. If it wasn't working for you before now, try again. It just needed an opensphd added to the end of it)

At this point, you will probably want to set up a share so you can easily transfer files from Windows to Ubuntu through a virtual network.
chmod 777 opensphd
sudo vi /etc/samba/smb.conf

You are now using vi. Search the web to find instructions on how to use vi, because you'll use it often.
Find the section called Share Definitions and add this
[opensphd]
comment = opensphd
path = /home/developer/opensphd
read only = no
guest ok = no


Now save that file.
sudo /etc/init.d/samba restart

sudo smbpasswd -a developer
and enter root for the password.

Now you can find out what your IP is using ifconfig and then browse that from the network. The netbios name will be something like developer-deskt if you used the user name as instructed above. Now you can start > run > \\192.168.6.133 (or whatever IP address was identified in ifconfig) and you should see the directory.

Now, back to Ubuntu. Switch to the buildroot directory.
cd ~/opensphd/buildroot

and make the config

make menuconfig

If this is your first time using the buildroot, then just select exit and save. Otherwise, feel free to select the additional packages you need.

now type:

make

and wait...a long time. It's going to take a few hours. It downloads each package needed and compiles it. The final result will be in the /opensphd/buildroot/binaries/uclibc/ and there will be a rootfs.mipsel.ext2 file, your toolchain.

Once you've built the toolchain, you can copy it to your screenplay drive and mount it and chroot to it. gcc works, but g++ stopped working on this version for some reason, so I didn't include it in the default menuconfig.

I would suggest doing development in the buildroot cross development environment. If it's one of the packages already included in the buildroot, then just go back into menuconfig and add it. Then make again and presto, it'll be in your toolchain file. It'll also be in one of the working directories on ubuntu, (project_build_mipsel/uclibc/root or something like that).

You should also be able to use the staging directory and do your own cross compiling. I'll detail that another day.

The uClibc had a few minor changes, which I added as a patch in the toolchain/uclibc directory. I also removed all of the .o and .a files from it, since it interferes with a good compile. Do not remove the .so files though. They are required for the build.

The Linux is also slightly modified. the mconf.c file had a reference to LC_ALL, which is normally defined in the locale.h (bits/locale.h) file. But that file isn't a part of the iomega published files, so I subsituted the actual value in. mconf.c is not a main part of the linux system anyway (I believe it's used for the menuconfig). I also removed all of the CVS/SVN and excess files to reduce the size from 150 MB down to 50 MB.

Oh yes, if you didn't notice, I have placed all of this on sourceforge as the opensphd (Open ScreenPlay Pro HD). Feel free to send me any patch files to improve the buildroot.

edit 4/26/2010: I have updated the files today. I figured out that the headers it was downloading were responsible from some of the problems. When I compared it with the conceptronic tools, I found that I could just use the unsanitized headers. This can easily be undone by deleting the linux-libc-headers-2.6.12.0.tar.bz2 file in the buildroot/dl directory. I also encountered the "mipsel-linux-objcopy missing" error discussed in the comments when I enabled initramfs. I was able to determine this was from the Makefile in the linux code that Iomega provided. it was not using the variables from Makefile so it would only find them if the staging_dir happened to be in your path. So I fixed that. The last thing I ran into was after g++ started compiling it then couldn't link on the device (worked fine from the PC staging directory but not on the ScreenPlay) because it was missing crt1.o and others. So I modified the scripts to copy those .o files as well when building the ext2 file.