A new version of U-Boot is out (here the announcement). U-Boot is a bootloader that aims to be flexible enough to be adapted to work on any architecture. This version (2010.09, that can be downloaded from their FTP server) adds Cache support to ARM architectures. The developers reported a couple of performance tests on a Beagle Board, and the results are, briefly:
The results show that common operations performed at boot time, such as copying zipped kernel images and initial RAM disks and then uncompressing them, will get a speed boost from this version on.