X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=MdeModulePkg%2FBus%2FPci%2FPciBusDxe%2FPciCommand.c;h=6283d602207cb09d89d8330d52fde94ac3d7c152;hp=601af309b7c2e76d7aa2b9f2944d39146e7b5ea5;hb=e5b4d825afc474a8cb916a2476dc0bb85fb32b2d;hpb=9060e3ec6dfd6048724832947933650cde873381

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
index 601af309b7..6283d60220 100644
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
@@ -1,14 +1,8 @@
 /** @file
   PCI command register operations supporting functions implementation for PCI Bus module.
 
-Copyright (c) 2006 - 2009, Intel Corporation
-All rights reserved. This program and the accompanying materials
-are licensed and made available under the terms and conditions of the BSD License
-which accompanies this distribution.  The full text of the license may be found at
-http://opensource.org/licenses/bsd-license.php
-
-THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
-WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
 
 **/
 
@@ -75,12 +69,12 @@ PciOperateRegister (
 }
 
 /**
-  Check the cpability supporting by given device.
+  Check the capability supporting by given device.
 
   @param PciIoDevice   Pointer to instance of PCI_IO_DEVICE.
 
-  @retval TRUE         Cpability supportted.
-  @retval FALSE        Cpability not supportted.
+  @retval TRUE         Capability supported.
+  @retval FALSE        Capability not supported.
 
 **/
 BOOLEAN
@@ -103,7 +97,7 @@ PciCapabilitySupport (
   @param Offset            A pointer to the offset returned.
   @param NextRegBlock      A pointer to the next block returned.
 
-  @retval EFI_SUCCESS      Successfuly located capability register block.
+  @retval EFI_SUCCESS      Successfully located capability register block.
   @retval EFI_UNSUPPORTED  Pci device does not support capability.
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.
 
@@ -121,7 +115,7 @@ LocateCapabilityRegBlock (
   UINT8   CapabilityID;
 
   //
-  // To check the cpability of this device supports
+  // To check the capability of this device supports
   //
   if (!PciCapabilitySupport (PciIoDevice)) {
     return EFI_UNSUPPORTED;
@@ -173,6 +167,14 @@ LocateCapabilityRegBlock (
       return EFI_SUCCESS;
     }
 
+    //
+    // Certain PCI device may incorrectly have capability pointing to itself,
+    // break to avoid dead loop.
+    //
+    if (CapabilityPtr == (UINT8) (CapabilityEntry >> 8)) {
+      break;
+    }
+
     CapabilityPtr = (UINT8) (CapabilityEntry >> 8);
   }
 
@@ -187,7 +189,7 @@ LocateCapabilityRegBlock (
   @param Offset            A pointer to the offset returned.
   @param NextRegBlock      A pointer to the next block returned.
 
-  @retval EFI_SUCCESS      Successfuly located capability register block.
+  @retval EFI_SUCCESS      Successfully located capability register block.
   @retval EFI_UNSUPPORTED  Pci device does not support capability.
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.
 
@@ -200,9 +202,10 @@ LocatePciExpressCapabilityRegBlock (
      OUT UINT32        *NextRegBlock OPTIONAL
   )
 {
-  UINT32  CapabilityPtr;
-  UINT32  CapabilityEntry;
-  UINT16  CapabilityID;
+  EFI_STATUS           Status;
+  UINT32               CapabilityPtr;
+  UINT32               CapabilityEntry;
+  UINT16               CapabilityID;
 
   //
   // To check the capability of this device supports
@@ -222,13 +225,29 @@ LocatePciExpressCapabilityRegBlock (
     // Mask it to DWORD alignment per PCI spec
     //
     CapabilityPtr &= 0xFFC;
-    PciIoDevice->PciIo.Pci.Read (
-                             &PciIoDevice->PciIo,
-                             EfiPciIoWidthUint32,
-                             CapabilityPtr,
-                             1,
-                             &CapabilityEntry
-                             );
+    Status = PciIoDevice->PciIo.Pci.Read (
+                                      &PciIoDevice->PciIo,
+                                      EfiPciIoWidthUint32,
+                                      CapabilityPtr,
+                                      1,
+                                      &CapabilityEntry
+                                      );
+    if (EFI_ERROR (Status)) {
+      break;
+    }
+
+    if (CapabilityEntry == MAX_UINT32) {
+      DEBUG ((
+        DEBUG_WARN,
+        "%a: [%02x|%02x|%02x] failed to access config space at offset 0x%x\n",
+        __FUNCTION__,
+        PciIoDevice->BusNumber,
+        PciIoDevice->DeviceNumber,
+        PciIoDevice->FunctionNumber,
+        CapabilityPtr
+        ));
+      break;
+    }
 
     CapabilityID = (UINT16) CapabilityEntry;