diff options
Diffstat (limited to 'drivers/gpu/drm/i915/i915_drv.c')
| -rw-r--r-- | drivers/gpu/drm/i915/i915_drv.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c index deaa32e8113b..062cbda1bf4a 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -465,9 +465,15 @@ 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; if (pch->vendor == PCI_VENDOR_ID_INTEL) { unsigned short id; id = pch->device & INTEL_PCH_DEVICE_ID_MASK; @@ -496,10 +502,18 @@ 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 { + goto check_next; } + pci_dev_put(pch); + break; } - pci_dev_put(pch); +check_next: + pch = pci_get_class(PCI_CLASS_BRIDGE_ISA << 8, curr); + pci_dev_put(curr); } + if (!pch) + DRM_DEBUG_KMS("No PCH found?\n"); } bool i915_semaphore_is_enabled(struct drm_device *dev) |