[E3-hacking] Just got an e3 - where do I start

[Aaro Koskinen]

Hi,

On Wed, Jun 27, 2012 at 09:52:46PM +0200, Janusz Krzysztofik wrote:
> > I am happy cross compiling a kernel... I guess
> > I can use any old ARM cross compiler?
> > 
> > What exactly is the boot process and how does this limit the size of the
> > kernel image? There's a way to get uboot on there - how can I do this? Does
> > the kernel always need to be sent over serial?
> 
> I use the old install tools, ramdisk and procedure published in 2006. 
> Works with new kernels built with my defconfig.

I'm using modified !LDR that loads and boots the kernel and initramfs
directly from NAND (they can also be sent over the the serial line). So
you don't really need U-boot at all (unless you need some fancy
features...).

Once you have booted succesfully, you can update the kernel just with
nandwrite. You need to send it over the serial only when booting for
the first time, or when you have flashed a kernel that does not work.

The NAND partitioning is static (hardcoded in the kernel). If I remember
correctly, the kernel partition is limited to 3.5 MB. My !LDR loads the
initramfs from "file system" partition which is tens of megabytes. In
practice these size limitations are not a problem.

For the userspace, you can use e.g. the latest Debian rootfs on USB disk.

A.