MdeModulePkg/PciBusDxe: Enumerator to check for RCiEP before looking for RP

Before trying to access parent root port to check ARI capabilities,
enumerator should see if Endpoint device is not Root Complex integrated
to avoid undefined parent register accesses.

Signed-off-by: Damian Bassa <damian.bassa@intel.com>
Reviewed-by: Ray Ni <ray.ni@intel.com>

1 files changed, 25 insertions, 1 deletions

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
index ed7f2d4ac6..9251388bc2 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciEnumeratorSupport.c
@@ -2116,6 +2116,27 @@ AuthenticatePciDevice (
 }

 

 /**

+  Checks if PCI device is Root Bridge.

+

+  @param PciIoDevice       Instance of PCI device

+

+  @retval TRUE             Device is Root Bridge

+  @retval FALSE            Device is not Root Bridge

+

+**/

+BOOLEAN

+IsRootBridge (

+  IN PCI_IO_DEVICE  *PciIoDevice

+  )

+{

+  if (PciIoDevice->Parent == NULL) {

+    return TRUE;

+  } else {

+    return FALSE;

+  }

+}

+

+/**

   Create and initialize general PCI I/O device instance for

   PCI device/bridge device/hotplug bridge device.

 

@@ -2217,7 +2238,10 @@ CreatePciIoDevice (
     return NULL;

   }

 

-  if (PcdGetBool (PcdAriSupport)) {

+  //

+  // Check if device's parent is not Root Bridge

+  //

+  if (PcdGetBool (PcdAriSupport) && !IsRootBridge (Bridge)) {

     //

     // Check if the device is an ARI device.

     //