[Gen9 Android Development] trevd:
More Research!

As I mentioned, I've been further looking into different booting methods and I think I'm approaching what could be a workable solution that will make the Gen9 more like standard android devices

Here's some more of my findings

1. It turns out that we can dump the existing initramfs.cpio.lzo and we can use a standard android ramdisk layout as the android init will load instead of the init script that is currently being used, this also removes the need for switch root and other nonsense that archos have in there. There was one gotcha when had me stumped for about ten minutes, I needed to add "write /sys/class/leds/lcd-backlight/brightness 75" to the init.rc to turn the screen on.

2. It's possible to stop android either using adb shell stop or stopping each service zygote etc, and start CWM while android is booted. It's probably also feasible the manage booting between recovery and android using the persist properties system which should make switching between the 2 fairly easy to control without much tweaking to any binaries. Looking at other devices, namely samsung, they seem to do something similar with recovery being in the same boot.img as the standard files, they simply load a recovery.rc instead of the main init.rc, this might mean that we have to patch CWM to load the correct init.rc I've not looked at the code properly yet but It's not going to be an issue anyway as all the code is fully available, You've gotta love open source. :)

3. By mounting /dev/block/mmcblk0p1 to /mnt/rawfs we are still able to use abcbox, reboot_into writes to the params file in the partition to control boot switching, so we can maintain booting into sde while leaving the stock android partition in place. I was unable to get any immediate joy from kd_flasher, that maybe because we currently have the ramdisk we want to overwrite mounted as the rootfs. Again I can't imagine it being too difficult to jig this, It can probably be worked out by looking at the current recovery ramdisk scripts should kd_flasher style functionality be required at any point.

4. Most of the binaries that rely on uClibc can be recompiled against bionic without any issue, usb_modeswitch for example. If there are any closed source ones, then the dynamic linker ld-uclibc or whatever is called, ultimately symlinks back to uClibc and we can just grab the one file and place it in the /lib directory. I tested /usr/bin/lsdvd in this way and It seemed to work fine.

I've got all this going on while still leaving a stock android fully intact, which is a great fallback Just in case.... Keeping these modifications at a safe level is one of the primary goals to enable much wider use

I'll put together some examples within the next couple of days to demostrate what I'm talking about here.

I've got a Linaro 4.1.1 ( JRO03R ) which has working powervr drivers with a 3.0.21 kernel, although that's about all that's working on it at the minute. :)

It's more a proof of concept than anything else, The kernel would need recompiling to add tracefs functionality which is required by jellybean but using the same magic should leave the powervr drivers functioning still, If anyone's interested I can stick that up, I've foolishly deleted ( misplaced/can't remember ) the device files I used to build this.... Too many android source trees and not using git properly leads to school boy errors. :D

I'm currently working on an omapzoom 4.1.2 tree using the blaze_tablet device as a base, I think this may yield the best results for the archos.

I suppose one other thing to do is the fix up a stock rom to use these methods and give it CWM, that should be pretty simple to do. Although ICS is ooold and I'm really not a fan of some of archos' methods e.g booting 4 different devices off one firmware. Although to their credit they do demostrate just what possible with deviating android from it's normal standard structures.

Hopefully this has whetted your appetites, I'm pretty excited about what's possible here :) as I feel it brings these archos devices in line with most others.