Your BIOS is aware of your motherboard's chipset, thus it might be
able to avoid problems with add-on cards that use memory-mapped
drivers. For instance, I would imagine that some chipset allow to
disable all ISA/PCI bus accesses while scanning for core memory. I
cannot tell, whether this is actually what some BIOS versions do, but
it would be a strong argument towards a BIOS based algorithm for
determining memory size, rather than probing from a normal user
program. And it is miles ahead of requiring the user to specify the
memory size. I am still "stuck" :-) with 32MB, but I would expect
larger machines to become increasingly popular.
I do think, that your proposal is sensible. Maybe you could code up a
sample patch and submit it to this list. Then, if nobody notices any
problems and if there are no other objections, maybe it gets included
in the official developers' kernel release. After all, the 2.1.x
kernels are meant for testing out new features.
Markus