On Sat, 13 Jul 2019, Jd Lyons wrote:
On Jul 13, 2019, at 1:01 PM, BALATON Zoltan balaton@eik.bme.hu wrote:
So is map-in map-out expected to work in OpenBIOS or is it known to be missing?
Map-in works, map-out is unimplemented, last I checked.
I could not find map-in either so I'm not sure it really works. I've checked in OpenFirmware and found a comment explaining the bug you've mentioned:
https://github.com/openbios/openfirmware/blob/master/dev/video/common/defer....
Not sure if that's useful but just for reference. Probably we don't need to emulate that bug. But we should have map-in map-out words. In OpenFirmware AFAIU these are implemented on the root node:
https://github.com/openbios/openfirmware/blob/master/cpu/ppc/rootnode.fth
and everything else just $call-parent to that. It basically should call claim to get a virtual address for the specified phys address I think.
OpenBIOS does have something similar in drivers/iommu.c but that's only used on sparc32. Should that be generalised and also used on ppc or is that really sparc specific?
Regards, BALATON Zoltan