Logic's demo is a decent starting point (you have to register a Zoom kit for access).

For cross toolchain, many people are using Code Sourcery Lite:
http://www.codesourcery.com/sgpp/lite/arm/portal/subscription?@template=lite

You can use the above toolchain to build the kernel. For kernel, start with the mainline from kernel.org then apply the Logic patch set.

For RFS, you can boot from Logic's elf, tar up the RFS files, and copy the archive to an SD card. Untar on your Linux desktop, then customize (edit startup scripts, rebuild busybox, etc.). Then you can build the file system image to load back on the target. Will post some additional notes on this later.

I eventually went with the TimeSys solution. Their "factory" build system saves a lot of time otherwise spent on book-keeping, and the build is fully automated. (I used labor-intensive manual build instructions prior to TimeSys).

~CN

Hi,

1) Here are my five cents to discussion about choice Linux development tools.
I think Openembedded is a good and powerful thing.
Although it is not easy and requires some time to understand how it works and how to customize it for own goals.

2) There are several methods to run linux with rootfs in memory. For example, I did the following:
a) compiled kernel with "ext2" support (I think it is default)
b) generated "ext2" rootfs and did it as an u-boot image (mkimage -A arm -O linux -T ramdisk -C none -d rootfs.ext2 rootfs.uboot)
c) loaded kernel and roofs images into memory (using u-boot or LoLo into 0x81000000 and 0x81300000)
d) "bootm 0x81000000 0x81300000" in u-boot