[PATCH] PCI: vmd: Only assign _OSC features in bare metal OS.

[Nirmal Patel <nirmal.patel@linux.intel.com>]

From: Nirmal Patel <nirmal.patel@intel.com>

Copy valid _OSC flags from root bridge only when OS can provide correct
values. In virtual machine, all of the control features are disabled as
hypervisor will not passthrough root bridge information to VM.

Signed-off-by: Nirmal Patel <nirmal.patel@linux.intel.com>
Reviewed-by:  Andy Shevchenko <andriy.shevchenko@intel.com>
---
 drivers/pci/controller/vmd.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/pci/controller/vmd.c b/drivers/pci/controller/vmd.c
index d4ae250d4bc6..f9e38f2f926a 100644
--- a/drivers/pci/controller/vmd.c
+++ b/drivers/pci/controller/vmd.c
@@ -910,8 +910,10 @@ static int vmd_enable_domain(struct vmd_dev *vmd, unsigned long features)
 		return -ENODEV;
 	}
 
-	vmd_copy_host_bridge_flags(pci_find_host_bridge(vmd->dev->bus),
-				   to_pci_host_bridge(vmd->bus->bridge));
+	/* Don't copy _OSC control flags in VM, it disables features.*/
+	if (!offset[0] || !offset[1])
+		vmd_copy_host_bridge_flags(pci_find_host_bridge(vmd->dev->bus),
+					 to_pci_host_bridge(vmd->bus->bridge));
 
 	vmd_attach_resources(vmd);
 	if (vmd->irq_domain)
-- 
2.43.0