It has been a while since the last post about ubuntu on the Transformer Prime. This post is going to explain a few of the new changes, and show a video preview of the system in action.
There have been a few changes since the last update:
3.1.10 Kernel -- Asus don’t update the kernel while remaining on the same android major release, so they won’t update the kernel until at least Jellybean, but we have worked really hard to bring us up to the latest kernel. This has given us the ability to use the latest Tegra ULP GeForce binary from nvidia and maintain acceleration with the latest releases.
Linux as a bootloader -- With some work to the process we have managed to get kexecboot working to give us a boot menu that will boot not only multiple kernels from eMMC, but also to allow booting from USB, SD, and MicroSD. At this point in time the guest kernel also requires two patches, one for speed (it is really slow to boot without this patch, 30sec-5minutes) and the second to copy ATAGS, this second patch is important so that the new initrd and command line get used.
Ubuntu 12.04 LTS -- The last image was 11.10 which is a little less stable. 12.04 has a new gpower applet which can read the battery levels. 12.04 also includes the mtrack driver allowing the trackpad to work. The biggest change with the new image is the use of armhf over armel.
LVM -- Turning mmcblk0p8 (/data under android) to an lvm volume group has allowed both android and ubuntu to coexist on the eMMC without needing nvflash for reformatting. This however does require a modification to the android initrd to reflect the change and for the lvm binary to be included so it can mount /data. Ubuntu natively supports booting from logical volumes.
Here is a video of this system in action. The video is a little bit rough cause I was trying to operate the camera and control the TF201 at the same time and I couldn’t keep it steady. I have also trimmed out booting CM9 for size reasons. If anyone would like to see both booting I can do a video just of dual booting.
I do not have an installer, or the files packed into an installable package yet, this is the next step that we are working on.