mapping small parts of a pci card to conserve KVA
gallatin at cs.duke.edu
Tue Feb 15 13:15:44 PST 2005
Scott Long writes:
> You can use pmap_mapdev() to create a KVA mapping of an arbitrary
> physaddr+len. In fact, this is exactly what newbus uses to create the
> PCI MEMIO resources when bus_alloc_resource() is called. I'm not sure
> if the range is mapped and activated before the driver makes that call,
> Warner or John might know for sure.
Thanks.. But since this is an out of tree driver, I want to stick
as much as I can to the normal driver APIs. If the KVA wastage
becomes a huge problem, I'll explore pmap_mapdev(), but for now
its not a big deal.
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