[RFC/PATCH] remove gratuitous reads from maple pci config space methods

Segher Boessenkool segher at kernel.crashing.org
Thu Aug 9 20:40:52 EST 2007


>> It might be worth checking that there isn't a particular reason for
>> these.  Just because posting writes are forbidden doesn't mean a
>> particular bridge won't screw it up...
>
> Well, I had already checked with Ben, who wrote the code, and my
> understanding is that the reads are intended to work around some
> misbehaving Apple bridges,

None of the PCI interfaces on the U3 or U4 bridges have that
problem as far as I know.  I think the workaround was copied
from code for older Apple bridges?

> but that a sync after the write (implied by
> releasing pci_lock in the generic pci code) should suffice for those.

I don't see how a sync could help here at all, not more than
an eieio anyway?


Segher




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