On Tue, Jun 25, 2013 at 05:57:44PM +1000, Benjamin Herrenschmidt wrote:

On Tue, 2013-06-25 at 15:47 +0800, Gavin Shan wrote:

quoted

If we just have complete reset for fenced PHB, we need restore it
from the cache (edev->config_space[1]) instead of reading that from
hardware. Fenced PHB is the special case on PowerNV :-)

Well not really...

In general we can also end up doing a hard reset under pHyp, and bridges
can lose their state as well, which means they need to be restored from
cache.

We don't see the real PHB, but we might see the bridges if we have a PE
that contains a bridge, for example, a PCIe card with a switch on it.

If we hard reset that (because the driver requested it) or if pHyp did a
reset due to a fence behind the scene, that bridge *will* have lost its
state and will need to be reconfigured too... or is RTAS doing it all ?

Ok. So that would be job of eeh_ops->configure_bridge(). On pSeries, it
should have done with that.

Thanks,
Gavin