[U-Boot-Users] Extremely tiny footprint

[Martin Krause]

Hi Laurent,

u-boot-users-bounces at lists.sourceforge.net wrote on :
> Hi everybody,
> 
> I would like to use U-Boot as a first-stage boot loader to program
> flash memory on the target board. The idea is to perform a two-steps
> procedure: 
> 
> 1. Program the first-stage boot loader in flash using JTAG (slow)

There are JTAG programmers, which could work very fast (e. g. BDI2000
with workspace enabled). The limiting factor is the flash itself,
not the programmer, or the JTAG interface.

> 2. The first-stage boot loader downloads the final boot loader
> (full-featured U-Boot) using TFTP and writes it to flash (fast)
> 
> To minimize time spent in step one, I need to make the first-stage
> boot loader as small as possible (hopefully less than 32kB). Has
> anyone ever stripped U-Boot that much ? Is there any documentation
> available ?

If programming speed is the only reason for your two-step approach,
then IMO this is not reasonable. It would be a waste of your time. Use
a faster JTAG programmer instead. Or you could buy the flashes 
preprogrammed.

Regards,
Martin