On 2014/6/25 18:21, Michael S. Tsirkin wrote:
On Wed, Jun 25, 2014 at 06:06:50PM +0800, Chen, Tiejun wrote:
On 2014/6/25 17:59, Paolo Bonzini wrote:
Il 25/06/2014 11:55, Michael S. Tsirkin ha scritto:
You're saying we will reserve a free BAR to address those
information to
expose to guest, but which device does this free BAR belong to? The
video
device? Or PCH/MCH?
If you just want to pass a couple of IDs, then don't, it's a waste.
But I still don't know what problem you are trying to solve,
looking at guest driver did not help.
It's not just a couple of IDs, it's also random fields of the MCH
configuration space. Grep drivers/gpu/drm/i915 for bridge_dev.
Paolo,
No, we're not pointing the bridge_dev here, which is a host bridge at
00:00.0.
Here it should be a ISA bridge at 00:1f.0. Please see intel_detect_pch() to
know why we need this.
Thanks
Tiejun
So what if you dont?
if (!pch)
DRM_DEBUG_KMS("No PCH found.\n");
Is that all? Seems harmless enough.
I don't read the whole driver completely so I don't know now. I guess the
driver may go other live path even without this setting in a live, or this
is a real bug to this driver on Intel platform.
But anyway, I think we should guarantee the driver work under the same
configuration as the native in the passthrough case.
Thanks
Tiejun