[PATCH] arm64: Enable PCI write-combine resources under sysfs

[Benjamin Herrenschmidt]

On Tue, 2020-09-15 at 07:42 +1000, Benjamin Herrenschmidt wrote:
> 
> > which is back to my original question, how do you do DMA using
> > /sys/xx/resources? Why not use VFIO like everything else?
> 
> Note: All this doesnt' change the fact that sys/xx/resources_wc
> exists
> for other archs and I see no reasons so far not to have it on ARM...

Also... it looks like VFIO also doesn't provide a way to do WC yet
unfortunately :-(

There was a discussion 2 or 3 years ago while I was at IBM about ways
to add that functionality, but it doesn't seem to have resulted in
anything.

Cheers,
Ben.