On Tue, Jun 18, 2013 at 08:54:35PM +0800, G.R. wrote: > On Sun, Dec 23, 2012 at 2:51 PM, G.R. <firemeteor at users.sourceforge.net> wrote: > >>> Hi Jesse, I think I need to resend the patch with proper comment to > >>> have it formally accepted. > >>> Any guide line for formal patch submission? Do I need to start a > >>> separate thread? > >> > >> No, just cc Daniel Vetter. > >> > >> -- > >> Jesse Barnes, Intel Open Source Technology Center > > > > Thanks, > > Resend with updated patch && Daniel involved. > > Also include the background info for easy reading. > > > > In XEN HVM guest, there is always an emulated PIIX3 ISA bridge on slot 01.0. > > This shadows the PCH ISA bridge on 1f.0 with the current > > intel_detect_pch() implementation. > > The issue can be easily solved by looping through all the ISA bridges > > until the first match is found, instead of just check against the > > first one. > > > > This seems to have lost in the list. Retry it again with latest > torvalds' kernel: > > diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c > index a2e4953..e38fa86 100644 > --- a/drivers/gpu/drm/i915/i915_drv.c > +++ b/drivers/gpu/drm/i915/i915_drv.c > @@ -454,11 +454,18 @@ void intel_detect_pch(struct drm_device *dev) > * make graphics device passthrough work easy for VMM, that only > * need to expose ISA bridge to let driver know the real hardware > * underneath. This is a requirement from virtualization team. > + * > + * In some virtualized environments (e.g. XEN), there is irrelevant > + * ISA bridge in the system. To work reliably, we should scan trhough > + * all the ISA bridge devices and check for the first match, instead > + * of only checking the first one. > */ > pch = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, NULL); > - if (pch) { > + while (pch) { > + struct pci_dev * curr = pch; ^ No space there. I think checkpatch should catch that. > if (pch->vendor == PCI_VENDOR_ID_INTEL) { > unsigned short id; > + unsigned found = 1; bool found = true; Although it would be easy to adjust the patch to not need a 'found' variable. > id = pch->device & INTEL_PCH_DEVICE_ID_MASK; > dev_priv->pch_id = id; > > @@ -490,10 +497,20 @@ void intel_detect_pch(struct drm_device *dev) > DRM_DEBUG_KMS("Found LynxPoint LP PCH\n"); > WARN_ON(!IS_HASWELL(dev)); > WARN_ON(!IS_ULT(dev)); > + } else { > + found = 0; > + } > + if (found) { > + BUG_ON(dev_priv->num_pch_pll > I915_NUM_PLLS); > + pci_dev_put(pch); > + break; > } > - BUG_ON(dev_priv->num_pch_pll > I915_NUM_PLLS); > } > - pci_dev_put(pch); > + pch = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, curr); > + pci_dev_put(curr); > + } > + if (!pch) { > + DRM_DEBUG_KMS("No PCH found?\n"); > } > } > _______________________________________________ > Intel-gfx mailing list > Intel-gfx at lists.freedesktop.org > http://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Ville Syrj?l? Intel OTC