mapping small parts of a pci card to conserve KVA

[Andrew Gallatin]

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.

Thanks again,

Drew