On Tue, Dec 14, 2004 at 01:26:55PM +0900, Hdei Nunoe wrote:
> >In 2.4 the support for CONFIG_DISCONTIG and CONFIG_NUMA are a bit tangled
> >with each other because IP27 is the only platform to uses these features
> >and it needs both.
> Is it named "sgi-ip27"?
Yes, obviously :-)
> >Other than that you can also just setup your system
> >as 0x0 - 0x10000000 being RAM, 0x10000000 - 0x20000000 being reserved
> >memory and 0x20000000 - 0x30000000 being highmem. Which works but is a
> >bit wasteful.
> The gap in physical memory is 0x10000000 - 0x20000000, but it is
> 0x90000000 -
> 0xC0000000 in virtual memory because there is K1 segment. So the macros
> as __pa() or __va() does not work, I think. Started to wonder it might not
> be easy
> as just changing the PAGE_OFFSET value. Do you see?
PAGE_OFFSET is the difference of a ZONE_NORMAL's virtual address and it's
physical address. Once there is no more 1:1 mapping between physical and
virtual addresses such as in your suggestion PAGE_OFFSET can no longer be
used, that is you need to rewrite all users of this function.