Thursday, November 13, 2014

Debian on BeagleBoard classic.

I have one of the original beagleboards with the omap3 processor, which is ARM+DSP coprocessor. Originally it used the Angstrom Linux distribution, which uses bitbake to build the kernel and all related software tools. I saw recently that Debian is now supported on this device; I like to run Debian on everything including my PC's, BeagleBone Black, and Raspberry Pi (raspbian - almost Debian), so why not on the beagleboard as well?
My hardware setup is a USB-serial adapter from a Linux (Debian, of course) host to the serial port of the Beagleboard. I also have a Sabrent USB-Ethernet adapter on the Beagleboard.
The "official" instructions seem to be at, which I found from Per those instructions, I downloaded the netinstall package from (using git of course), and put it on a 16GB SD card using the command:
sudo ./ --mmc $SDCARD --dtb omap3-beagle --distro wheezy-armhf --firmware --serial-mode
On my PC I have SDCARD=/dev/sdb, because that's where the memory card shows up when it's plugged in. MAKE SURE you get this right, because you could wipe out a disk on the PC if you get it wrong. I decided to uses the --serial-mode option to work from the serial port and avoid any HDMI display issues.
Moved the SD card from the PC to Beagleboard, powered up, and got a typical Debian install menu on the serial port! I used
minicom -D /dev/usb/prolific2303 -b 115200 -o
to connect to the USB-serial port. The Beagleboard serial port does not use the modem control lines, so had to turn off the "Hardware Flow Control" and "Modem has DCD" options in minicom.
The netinstall process was just like installing Debian on a PC: select some options and wait for it to download a bunch of packages. It found the Sabrent ethernet and used it with no problem; device usb0 shows up as a network device as well, so it should be possible to install by using a USB connection to the PC host, but I didn't try that.
Finished the install, rebooted the Beagleboard, aaaannnd - nothing happened!!! Load process just stopped in uboot. After a few hours of screaming, hair-pulling, and spelunking in uboot macros, I found the problem:
I had set up /boot as a separate partition.
The uboot macros look for  /boot/uEnv.txt on each partition and then boot Linux using that partition as the root partition. Made /boot a normal directory instead of a mount point, patched up /etc/fstab, and uboot brought up Debian with no problem.
Did my usual Debian tweaks ( and everything seems to be working as expected.