On 07/24/2017 11:50 AM, David Gibson wrote: > On Mon, Jul 24, 2017 at 05:00:57PM +1000, Benjamin Herrenschmidt wrote: >> On Mon, 2017-07-24 at 14:36 +1000, David Gibson wrote: >>> On Wed, Jul 05, 2017 at 07:13:21PM +0200, Cédric Le Goater wrote: >>>> These flags define some characteristics of the source : >>>> >>>> - XIVE_SRC_H_INT_ESB the Event State Buffer are controlled with a >>>> specific hcall H_INT_ESB >>> >>> What's the other option? >> >> Direct MMIO access. Normally all interrupts use normal MMIOs, >> each interrupts has an associated MMIO page with special MMIOs >> to control the source state (PQ bits). This is something I added >> to the PAPR spec (and the OPAL <-> Linux interface) to allow firmware >> to work around broken HW (which happens on some P9 versions). > > Ok.. and that's something that can be decided at runtime? >
This is a characteristic of an Interrupt Source and the associated object should be created with such a flag. But I don't think will ever use it in QEMU, maybe with KVM. C.
