I'm porting u-boot to the Sharp KEV7A400 development board. The CPU has an ARM9 core with some Sharp and some ARM cells. The existing ARM920T cpu code has quite a bit of Samsung specific code in it. So, the question is this: how do we best handle development like this? For time time being, I'm creating a new CPU directory to eliminate a ridiculous set of ifdefs. However, this may not be a good long-term solution.

I've been musing about solving the problem and have come up with some ideas, though nothing yet comprehensivve.

1) It seems to be a mistake to put manufacturer specific code in the CPU directory unless we equate CPU not to the *core* but to the implementation of the core. For example, not x86, but AMD Elan. Not ARM920T but Sharp LH7a400. In the embedded market, this makes more sense than it does for x86 PCs. 2) There are some board-specific driver choices, e.g. serial driver, that sometimes appear in the CPU directory. Perhaps these choices are best made in the board directory instead. 3) Drivers, such as serial, could be made to export a function table. This would allow driver selection by choosing which file to compile and link.

At this point, I'm looking to start a discussion about this. I've seen the same kinds of problems twice, now. I'd like to find out how best to fix them.

Cheers.