22 Oct
2012
22 Oct
'12
3:27 p.m.
On 10/19/12 1:43 PM, Lucas Kannebley Tavares wrote:
The radeon driver does speed cap detection on the root PCI device for the maximum speed with which the adapter can communicate. On ppc64 systems, however, the root device belongs to the Hypervisor, so the current code would case a null pointer dereference.
I propose to look for the outmost bus with a parent node and get speed caps from it, though I suppose the cleaner way would be to inspect all devices along the way and choose the smallest speed cap.
That (walking all parent nodes) is probably the safest thing to do. I'm not sure whether it's optimal. It would likely depend on whether you can meaningfully have a bridge that's faster on the downstream side than on the upstream.
- ajax