On Wednesday 19 March 2008 16:41, Felipe Balbi wrote: > >>> - Discard U-Boot, minimal bootloader direct to kernel > > Hence "direct to kernel". > And that's what a bootloader should do and only that. But you're > missing memory access timings :-p > We don't need such a big bootloader like u-boot. It should be used, > maybe, only during the product development on debugging purposes. You are absolutely right. But I remember about 20 months ago, I was writing a custom bootloader for s3c2442 (typically a nand loader for SteppingStone) it was able to set the correct registers for Linux, memory timings and serial port. And it was as little as 3.5k. Linux booted nicely for hours or weeks, but when some program was trying to use all memory available, it crashed with a kernel panic. When I was investigating why, I found u-boot patches from openmoko, so I gave it a try. It worked with no problem, and those crashed went away.
I thought I didn't set all memory registers correctly, but I was too lazy to find out why. So I switched to u-boot. To my opinion if you are willing to spend more than 4 hours writing a bootloader bigger than 4k and with SD Card boot feature (vfat?) you better switch to u-boot. It is more robust. It has all stuff we need from a bootloader. Just my 2 cents, Regards, -- Gianluca Renzi
