The README file explains it all. You can flash dual boot in your A320 both from Windows and Linux. Note that the installer will give you the ability to select from original firmware on internal flash or linux on miniSD. The later means the dual boot code will look for a zImage kernel file in the first partition of the miniSD and launch it. That's all.
IMPORTANT: I'm almost 100% sure the ILI9331 variant works fine, but could not test it since the newer A320 (paid by your generous donations) hasn't arrived yet. Postal service sucks big time here. If you have any troubles, please let me know.
Some notes for rootfs developers:
- The flashed U-Boot environment can't be changed. It just loads a zImage from miniSD and that's all.
- If you want to pass special command line parameters to the kernel, you must embed them in the zImage (see CONFIG_CMDLINE). That means you need to recompile the kernel.
- If you want an initramfs, you'll also have to embed it into the kernel (see CONFIG_INITRAMFS_SOURCE).
This is how the installer works: the instructions let you boot a zImage. It's just the kernel with three particularities:
- The console font size is set to 8x16 (instead of the tiny one).
- The NAND flash support is enabled and forced to 2K page size (required to properly write the SPL area which is the first eraseblock).
- There is an embedded initramfs which contains libc, busybox, mtd-tools, dialog, and a script that executes on startup, shows a disclaimer and does the job.
UPDATE 1: yes, the logo is shown even if you are booting into the original firmware. I though it was nice to show it as sort of saying "this A320 is modded to boot linux". However, it can be easily changed if enough people prefer it not shown.
UPDATE 2: please please please read the keyboard related section of this document. It explains the current key map and special key combinations in linux, in particular how to reboot the machine. I've noticed that the immediate reboot key combination (POWER+START+SELECT) is a bit inconvenient if you are rebootint into the original firmware, because you must be quick releasing SELECT or you boot again into linux. This wasn't a problem when boot selection was being done by U-Boot because it takes a little time to load, but now selection is done right in the SPL, in fact the SELECT key state reading is the first thing done. I'll be glad to hear your comments and suggestions on this issue.
UPDATE 3: some clarification: the dual-boot installer lets you boot linux withou having to use a PC. But you had to have linux installed already in your miniSD as described in the QuickStart guide in the wiki section of the google code project page. I guess it's been a bit confusing that I've released a kernel image at the same time than the dual boot installer. You still need to install the root filesystem in a second ext2/ext3 partition.
UPDATE 4: yes, formatting and installing the root filesystem from windows is not yet solved, but it is not difficult and someone (maybe me) will do it soon. All we need is to place the rootfs file in the FAT partition and embed a initramfs into the zImage that will first mount the FAT partition and then the rootfs file as a loopback device.