On 1 Mar 2001, Eric W. Biederman wrote:
> Now that I know I can fake a stack and various other data in
> the cache instead of RAM I'm trying to figure out how to best take
> advantage of it.
here's something to worry about. given a certain type of writeback (WB)
set-associative cache, we're going to be assuming that we won't ever have
some sort of cache line collision that would trigger a WB. If we do
trigger WB, and ram is not up, it's all over. The processor will write
data out, causing very bad things to happen to the not-set-up sdram, and
at some point might try to read that line back in again -- still worse. I
realize this is unlikely in the current setup, but as linuxbios evolves,
who knows what might change.
I'm not sure I'm comfortable modifying linuxbios to assume this will work
across all the processors we might ever use. So, I want to make it
continue to work both ways.
I'd like to stick with the current structure, but modify the low-level
assembly to have the option to call out to C for ram init, so that we can
easily turn the cache feature on and off.
that said, I'm really looking forward to trying this out. It could be a
real lifesaver.
ron
