MdeModulePkg/PciBusDxe: catch unimplemented extended config space reads

[mirror_edk2.git] / MdeModulePkg / Bus / Pci / PciBusDxe / PciCommand.c

diff --git a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
index 601af309b7c2e76d7aa2b9f2944d39146e7b5ea5..6283d602207cb09d89d8330d52fde94ac3d7c152 100644 (file)
--- a/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
+++ b/MdeModulePkg/Bus/Pci/PciBusDxe/PciCommand.c
@@ -1,14 +1,8 @@
 /** @file\r
   PCI command register operations supporting functions implementation for PCI Bus module.\r
 \r
 /** @file\r
   PCI command register operations supporting functions implementation for PCI Bus module.\r
 \r

-Copyright (c) 2006 - 2009, Intel Corporation\r
-All rights reserved. This program and the accompanying materials\r
-are licensed and made available under the terms and conditions of the BSD License\r
-which accompanies this distribution.  The full text of the license may be found at\r
-http://opensource.org/licenses/bsd-license.php\r
-\r
-THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
-WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
+Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>\r
+SPDX-License-Identifier: BSD-2-Clause-Patent\r

 \r
 **/\r
 \r
 \r
 **/\r
 \r


@@ -75,12 +69,12 @@ PciOperateRegister (
 }\r
 \r
 /**\r
 }\r
 \r
 /**\r

-  Check the cpability supporting by given device.\r
+  Check the capability supporting by given device.\r

 \r
   @param PciIoDevice   Pointer to instance of PCI_IO_DEVICE.\r
 \r
 \r
   @param PciIoDevice   Pointer to instance of PCI_IO_DEVICE.\r
 \r

-  @retval TRUE         Cpability supportted.\r
-  @retval FALSE        Cpability not supportted.\r
+  @retval TRUE         Capability supported.\r
+  @retval FALSE        Capability not supported.\r

 \r
 **/\r
 BOOLEAN\r
 \r
 **/\r
 BOOLEAN\r


@@ -103,7 +97,7 @@ PciCapabilitySupport (
   @param Offset            A pointer to the offset returned.\r
   @param NextRegBlock      A pointer to the next block returned.\r
 \r
   @param Offset            A pointer to the offset returned.\r
   @param NextRegBlock      A pointer to the next block returned.\r
 \r

-  @retval EFI_SUCCESS      Successfuly located capability register block.\r
+  @retval EFI_SUCCESS      Successfully located capability register block.\r

   @retval EFI_UNSUPPORTED  Pci device does not support capability.\r
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.\r
 \r
   @retval EFI_UNSUPPORTED  Pci device does not support capability.\r
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.\r
 \r


@@ -121,7 +115,7 @@ LocateCapabilityRegBlock (
   UINT8   CapabilityID;\r
 \r
   //\r
   UINT8   CapabilityID;\r
 \r
   //\r

-  // To check the cpability of this device supports\r
+  // To check the capability of this device supports\r

   //\r
   if (!PciCapabilitySupport (PciIoDevice)) {\r
     return EFI_UNSUPPORTED;\r
   //\r
   if (!PciCapabilitySupport (PciIoDevice)) {\r
     return EFI_UNSUPPORTED;\r


@@ -173,6 +167,14 @@ LocateCapabilityRegBlock (
       return EFI_SUCCESS;\r
     }\r
 \r
       return EFI_SUCCESS;\r
     }\r
 \r

+    //\r
+    // Certain PCI device may incorrectly have capability pointing to itself,\r
+    // break to avoid dead loop.\r
+    //\r
+    if (CapabilityPtr == (UINT8) (CapabilityEntry >> 8)) {\r
+      break;\r
+    }\r
+\r

     CapabilityPtr = (UINT8) (CapabilityEntry >> 8);\r
   }\r
 \r
     CapabilityPtr = (UINT8) (CapabilityEntry >> 8);\r
   }\r
 \r


@@ -187,7 +189,7 @@ LocateCapabilityRegBlock (
   @param Offset            A pointer to the offset returned.\r
   @param NextRegBlock      A pointer to the next block returned.\r
 \r
   @param Offset            A pointer to the offset returned.\r
   @param NextRegBlock      A pointer to the next block returned.\r
 \r

-  @retval EFI_SUCCESS      Successfuly located capability register block.\r
+  @retval EFI_SUCCESS      Successfully located capability register block.\r

   @retval EFI_UNSUPPORTED  Pci device does not support capability.\r
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.\r
 \r
   @retval EFI_UNSUPPORTED  Pci device does not support capability.\r
   @retval EFI_NOT_FOUND    Pci device support but can not find register block.\r
 \r


@@ -200,9 +202,10 @@ LocatePciExpressCapabilityRegBlock (
      OUT UINT32        *NextRegBlock OPTIONAL\r
   )\r
 {\r
      OUT UINT32        *NextRegBlock OPTIONAL\r
   )\r
 {\r

-  UINT32  CapabilityPtr;\r
-  UINT32  CapabilityEntry;\r
-  UINT16  CapabilityID;\r
+  EFI_STATUS           Status;\r
+  UINT32               CapabilityPtr;\r
+  UINT32               CapabilityEntry;\r
+  UINT16               CapabilityID;\r

 \r
   //\r
   // To check the capability of this device supports\r
 \r
   //\r
   // To check the capability of this device supports\r


@@ -222,13 +225,29 @@ LocatePciExpressCapabilityRegBlock (
     // Mask it to DWORD alignment per PCI spec\r
     //\r
     CapabilityPtr &= 0xFFC;\r
     // Mask it to DWORD alignment per PCI spec\r
     //\r
     CapabilityPtr &= 0xFFC;\r

-    PciIoDevice->PciIo.Pci.Read (\r
-                             &PciIoDevice->PciIo,\r
-                             EfiPciIoWidthUint32,\r
-                             CapabilityPtr,\r
-                             1,\r
-                             &CapabilityEntry\r
-                             );\r
+    Status = PciIoDevice->PciIo.Pci.Read (\r
+                                      &PciIoDevice->PciIo,\r
+                                      EfiPciIoWidthUint32,\r
+                                      CapabilityPtr,\r
+                                      1,\r
+                                      &CapabilityEntry\r
+                                      );\r
+    if (EFI_ERROR (Status)) {\r
+      break;\r
+    }\r
+\r
+    if (CapabilityEntry == MAX_UINT32) {\r
+      DEBUG ((\r
+        DEBUG_WARN,\r
+        "%a: [%02x|%02x|%02x] failed to access config space at offset 0x%x\n",\r
+        __FUNCTION__,\r
+        PciIoDevice->BusNumber,\r
+        PciIoDevice->DeviceNumber,\r
+        PciIoDevice->FunctionNumber,\r
+        CapabilityPtr\r
+        ));\r
+      break;\r
+    }\r

 \r
     CapabilityID = (UINT16) CapabilityEntry;\r
 \r
 \r
     CapabilityID = (UINT16) CapabilityEntry;\r
 \r