On Mon, 14 Jan 2002, Matthew Dharm wrote:
> Does this mean we could map PCI memory/IO addresses above 4G and have
> it work?
Ooh, don't go there :> We looked at that and actually did it then backed
it out.
The PCI spec (particuarly PCI-X) tries to make it possible, but in a
general system with PCI sockets/etc it is just is not feasible. PCI
bridges need to be located below 4G, as do the majority of devices made.
There is also a performance hit for having device registers > 4G.
You'd definately need the mips64 kernel to do that, or use ugly wired TLB
entries with normal mips.
Jason
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