DynamicTablesPkg: AcpiSsdtPcieLibArm: Create support library

Add support library to allow for customization of _OSC and slot info.
The functions in the library are unchanged,
with the exception of adding PciInfo pointer to the APIs.

Signed-off-by: Jeff Brasen <jbrasen@nvidia.com>
Reviewed-by: Pierre Gondois <pierre.gondois@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>

11 files changed, 337 insertions, 187 deletions

diff --git a/DynamicTablesPkg/DynamicTables.dsc.inc b/DynamicTablesPkg/DynamicTables.dsc.inc
index 60bcf4b199..3d4fa0c4c4 100644
--- a/DynamicTablesPkg/DynamicTables.dsc.inc
+++ b/DynamicTablesPkg/DynamicTables.dsc.inc
@@ -15,6 +15,7 @@
 [LibraryClasses.common]

   AcpiHelperLib|DynamicTablesPkg/Library/Common/AcpiHelperLib/AcpiHelperLib.inf

   AmlLib|DynamicTablesPkg/Library/Common/AmlLib/AmlLib.inf

+  SsdtPcieSupportLib|DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.inf

   SsdtSerialPortFixupLib|DynamicTablesPkg/Library/Common/SsdtSerialPortFixupLib/SsdtSerialPortFixupLib.inf

   TableHelperLib|DynamicTablesPkg/Library/Common/TableHelperLib/TableHelperLib.inf

 

diff --git a/DynamicTablesPkg/DynamicTablesPkg.dec b/DynamicTablesPkg/DynamicTablesPkg.dec
index 9b74c5a671..cc34c2bdd6 100644
--- a/DynamicTablesPkg/DynamicTablesPkg.dec
+++ b/DynamicTablesPkg/DynamicTablesPkg.dec
@@ -30,6 +30,9 @@
   ##  @libraryclass  Defines a set of APIs to a hardware information parser.

   HwInfoParserLib|Include/Library/HwInfoParserLib.h

 

+  ##  @libraryclass Defines functions for customizing the generation of _OSC and slot info.

+  SsdtPcieSupportLib|Include/Library/SsdtPcieSupportLib.h

+

   ##  @libraryclass  Defines a set of methods for fixing up a SSDT Serial Port.

   SsdtSerialPortFixupLib|Include/Library/SsdtSerialPortFixupLib.h

 

diff --git a/DynamicTablesPkg/DynamicTablesPkg.dsc b/DynamicTablesPkg/DynamicTablesPkg.dsc
index 068f0bc630..07cc837552 100644
--- a/DynamicTablesPkg/DynamicTablesPkg.dsc
+++ b/DynamicTablesPkg/DynamicTablesPkg.dsc
@@ -41,6 +41,7 @@
 [Components.common]

   DynamicTablesPkg/Library/Common/AcpiHelperLib/AcpiHelperLib.inf

   DynamicTablesPkg/Library/Common/AmlLib/AmlLib.inf

+  DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.inf

   DynamicTablesPkg/Library/Common/SsdtSerialPortFixupLib/SsdtSerialPortFixupLib.inf

   DynamicTablesPkg/Library/Common/TableHelperLib/TableHelperLib.inf

   DynamicTablesPkg/Library/FdtHwInfoParserLib/FdtHwInfoParserLib.inf

diff --git a/DynamicTablesPkg/Include/Library/SsdtPcieSupportLib.h b/DynamicTablesPkg/Include/Library/SsdtPcieSupportLib.h
new file mode 100644
index 0000000000..85e283a994
--- /dev/null
+++ b/DynamicTablesPkg/Include/Library/SsdtPcieSupportLib.h
@@ -0,0 +1,73 @@
+/** @file

+  Ssdt PCIe Support Library

+

+  Copyright (c) 2021 - 2022, Arm Limited. All rights reserved.<BR>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+**/

+

+#ifndef SSDT_PCIE_SUPPORT_LIB_H_

+#define SSDT_PCIE_SUPPORT_LIB_H_

+

+#pragma pack(1)

+

+/** Structure used to map integer to an index.

+*/

+typedef struct MappingTable {

+  /// Mapping table.

+  /// Contains the Index <-> integer mapping

+  UINT32    *Table;

+

+  /// Last used index of the Table.

+  /// Bound by MaxIndex.

+  UINT32    LastIndex;

+

+  /// Number of entries in the Table.

+  UINT32    MaxIndex;

+} MAPPING_TABLE;

+

+#pragma pack()

+

+/** Add an _OSC template method to the PciNode.

+

+  The _OSC method is provided as an AML blob. The blob is

+  parsed and attached at the end of the PciNode list of variable elements.

+

+  @param [in]       PciInfo     Pci device information.

+  @param [in, out]  PciNode     Pci node to amend.

+

+  @retval EFI_SUCCESS             The function completed successfully.

+  @retval EFI_INVALID_PARAMETER   Invalid parameter.

+  @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.

+**/

+EFI_STATUS

+EFIAPI

+AddOscMethod (

+  IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO  *PciInfo,

+  IN  OUT   AML_OBJECT_NODE_HANDLE            PciNode

+  );

+

+/** Generate Pci slots devices.

+

+  PCI Firmware Specification - Revision 3.3,

+  s4.8 "Generic ACPI PCI Slot Description" requests to describe the PCI slot

+  used. It should be possible to enumerate them, but this is additional

+  information.

+

+  @param [in]       PciInfo     Pci device information.

+  @param [in]  MappingTable     The mapping table structure.

+  @param [in, out]  PciNode     Pci node to amend.

+

+  @retval EFI_SUCCESS            Success.

+  @retval EFI_INVALID_PARAMETER  Invalid parameter.

+  @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.

+**/

+EFI_STATUS

+EFIAPI

+GeneratePciSlots (

+  IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO  *PciInfo,

+  IN      CONST MAPPING_TABLE                 *MappingTable,

+  IN  OUT       AML_OBJECT_NODE_HANDLE        PciNode

+  );

+

+#endif // SSDT_PCIE_SUPPORT_LIB_H_

diff --git a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.c b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.c
index 3b3d904dbe..ceffe2838c 100644
--- a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.c
+++ b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.c
@@ -29,6 +29,7 @@
 #include <Library/AcpiHelperLib.h>

 #include <Library/TableHelperLib.h>

 #include <Library/AmlLib/AmlLib.h>

+#include <Library/SsdtPcieSupportLib.h>

 #include <Protocol/ConfigurationManagerProtocol.h>

 

 #include "SsdtPcieGenerator.h"

@@ -280,86 +281,6 @@ GeneratePciDeviceInfo (
   return Status;

 }

 

-/** Generate Pci slots devices.

-

-  PCI Firmware Specification - Revision 3.3,

-  s4.8 "Generic ACPI PCI Slot Description" requests to describe the PCI slot

-  used. It should be possible to enumerate them, but this is additional

-  information.

-

-  @param [in]  MappingTable  The mapping table structure.

-  @param [in, out]  PciNode     Pci node to amend.

-

-  @retval EFI_SUCCESS            Success.

-  @retval EFI_INVALID_PARAMETER  Invalid parameter.

-  @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.

-**/

-STATIC

-EFI_STATUS

-EFIAPI

-GeneratePciSlots (

-  IN      CONST MAPPING_TABLE           *MappingTable,

-  IN  OUT       AML_OBJECT_NODE_HANDLE  PciNode

-  )

-{

-  EFI_STATUS              Status;

-  UINT32                  Index;

-  UINT32                  LastIndex;

-  UINT32                  DeviceId;

-  CHAR8                   AslName[AML_NAME_SEG_SIZE + 1];

-  AML_OBJECT_NODE_HANDLE  DeviceNode;

-

-  ASSERT (MappingTable != NULL);

-  ASSERT (PciNode != NULL);

-

-  // Generic device name is "Dxx".

-  CopyMem (AslName, "Dxx_", AML_NAME_SEG_SIZE + 1);

-

-  LastIndex = MappingTable->LastIndex;

-

-  // There are at most 32 devices on a Pci bus.

-  if (LastIndex >= 32) {

-    ASSERT (0);

-    return EFI_INVALID_PARAMETER;

-  }

-

-  for (Index = 0; Index < LastIndex; Index++) {

-    DeviceId                       = MappingTable->Table[Index];

-    AslName[AML_NAME_SEG_SIZE - 3] = AsciiFromHex (DeviceId & 0xF);

-    AslName[AML_NAME_SEG_SIZE - 2] = AsciiFromHex ((DeviceId >> 4) & 0xF);

-

-    // ASL:

-    // Device (Dxx) {

-    //   Name (_ADR, <address value>)

-    // }

-    Status = AmlCodeGenDevice (AslName, PciNode, &DeviceNode);

-    if (EFI_ERROR (Status)) {

-      ASSERT (0);

-      return Status;

-    }

-

-    /* ACPI 6.4 specification, Table 6.2: "ADR Object Address Encodings"

-       High word-Device #, Low word-Function #. (for example, device 3,

-       function 2 is 0x00030002). To refer to all the functions on a device #,

-       use a function number of FFFF).

-    */

-    Status = AmlCodeGenNameInteger (

-               "_ADR",

-               (DeviceId << 16) | 0xFFFF,

-               DeviceNode,

-               NULL

-               );

-    if (EFI_ERROR (Status)) {

-      ASSERT (0);

-      return Status;

-    }

-

-    // _SUN object is not generated as we don't know which slot will be used.

-  }

-

-  return Status;

-}

-

 /** Generate a _PRT object (Pci Routing Table) for the Pci device.

 

   Cf. ACPI 6.4 specification, s6.2.13 "_PRT (PCI Routing Table)"

@@ -495,7 +416,7 @@ GeneratePrt (
   PrtNode = NULL;

 

   // Generate the Pci slots once all the device have been added.

-  Status = GeneratePciSlots (&Generator->DeviceTable, PciNode);

+  Status = GeneratePciSlots (PciInfo, &Generator->DeviceTable, PciNode);

   if (EFI_ERROR (Status)) {

     ASSERT (0);

     goto exit_handler;

@@ -695,89 +616,6 @@ GeneratePciCrs (
   return Status;

 }

 

-/** Add an _OSC template method to the PciNode.

-

-  The _OSC method is provided as an AML blob. The blob is

-  parsed and attached at the end of the PciNode list of variable elements.

-

-  @param [in, out]  PciNode     Pci node to amend.

-

-  @retval EFI_SUCCESS             The function completed successfully.

-  @retval EFI_INVALID_PARAMETER   Invalid parameter.

-  @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.

-**/

-STATIC

-EFI_STATUS

-EFIAPI

-AddOscMethod (

-  IN  OUT   AML_OBJECT_NODE_HANDLE  PciNode

-  )

-{

-  EFI_STATUS                   Status;

-  EFI_STATUS                   Status1;

-  EFI_ACPI_DESCRIPTION_HEADER  *SsdtPcieOscTemplate;

-  AML_ROOT_NODE_HANDLE         OscTemplateRoot;

-  AML_OBJECT_NODE_HANDLE       OscNode;

-

-  ASSERT (PciNode != NULL);

-

-  // Parse the Ssdt Pci Osc Template.

-  SsdtPcieOscTemplate = (EFI_ACPI_DESCRIPTION_HEADER *)

-                        ssdtpcieosctemplate_aml_code;

-

-  OscNode         = NULL;

-  OscTemplateRoot = NULL;

-  Status          = AmlParseDefinitionBlock (

-                      SsdtPcieOscTemplate,

-                      &OscTemplateRoot

-                      );

-  if (EFI_ERROR (Status)) {

-    DEBUG ((

-      DEBUG_ERROR,

-      "ERROR: SSDT-PCI-OSC: Failed to parse SSDT PCI OSC Template."

-      " Status = %r\n",

-      Status

-      ));

-    return Status;

-  }

-

-  Status = AmlFindNode (OscTemplateRoot, "\\_OSC", &OscNode);

-  if (EFI_ERROR (Status)) {

-    goto error_handler;

-  }

-

-  Status = AmlDetachNode (OscNode);

-  if (EFI_ERROR (Status)) {

-    goto error_handler;

-  }

-

-  Status = AmlAttachNode (PciNode, OscNode);

-  if (EFI_ERROR (Status)) {

-    // Free the detached node.

-    AmlDeleteTree (OscNode);

-    goto error_handler;

-  }

-

-error_handler:

-  // Cleanup

-  Status1 = AmlDeleteTree (OscTemplateRoot);

-  if (EFI_ERROR (Status1)) {

-    DEBUG ((

-      DEBUG_ERROR,

-      "ERROR: SSDT-PCI-OSC: Failed to cleanup AML tree."

-      " Status = %r\n",

-      Status1

-      ));

-    // If Status was success but we failed to delete the AML Tree

-    // return Status1 else return the original error code, i.e. Status.

-    if (!EFI_ERROR (Status)) {

-      return Status1;

-    }

-  }

-

-  return Status;

-}

-

 /** Generate a Pci device.

 

   @param [in]       Generator       The SSDT Pci generator.

@@ -865,7 +703,7 @@ GeneratePciDevice (
   }

 

   // Add the template _OSC method.

-  Status = AddOscMethod (PciNode);

+  Status = AddOscMethod (PciInfo, PciNode);

   ASSERT_EFI_ERROR (Status);

   return Status;

 }

diff --git a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.h b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.h
index 515a3e1785..7410f9ffd4 100644
--- a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.h
+++ b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieGenerator.h
@@ -36,29 +36,8 @@
 // _SB scope of the AML namespace.

 #define SB_SCOPE  "\\_SB_"

 

-/** C array containing the compiled AML template.

-    This symbol is defined in the auto generated C file

-    containing the AML bytecode array.

-*/

-extern CHAR8  ssdtpcieosctemplate_aml_code[];

-

 #pragma pack(1)

 

-/** Structure used to map integer to an index.

-*/

-typedef struct MappingTable {

-  /// Mapping table.

-  /// Contains the Index <-> integer mapping

-  UINT32    *Table;

-

-  /// Last used index of the Table.

-  /// Bound by MaxIndex.

-  UINT32    LastIndex;

-

-  /// Number of entries in the Table.

-  UINT32    MaxIndex;

-} MAPPING_TABLE;

-

 /** A structure holding the Pcie generator and additional private data.

 */

 typedef struct AcpiPcieGenerator {

diff --git a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.inf b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.inf
index 283b564801..b38a4e9d34 100644
--- a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.inf
+++ b/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieLibArm.inf
@@ -19,7 +19,6 @@
 [Sources]

   SsdtPcieGenerator.c

   SsdtPcieGenerator.h

-  SsdtPcieOscTemplate.asl

 

 [Packages]

   DynamicTablesPkg/DynamicTablesPkg.dec

@@ -30,3 +29,4 @@
   AcpiHelperLib

   AmlLib

   BaseLib

+  SsdtPcieSupportLib

diff --git a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieOscTemplate.asl b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieOscTemplate.asl
index feaf56b533..feaf56b533 100644
--- a/DynamicTablesPkg/Library/Acpi/Arm/AcpiSsdtPcieLibArm/SsdtPcieOscTemplate.asl
+++ b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieOscTemplate.asl
diff --git a/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.c b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.c
new file mode 100644
index 0000000000..e5ab3a3ca8
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.c
@@ -0,0 +1,200 @@
+/** @file

+  SSDT PCIe Support Library.

+

+  Copyright (c) 2021 - 2022, Arm Limited. All rights reserved.<BR>

+

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+  @par Reference(s):

+  - PCI Firmware Specification - Revision 3.0

+  - ACPI 6.4 specification:

+   - s6.2.13 "_PRT (PCI Routing Table)"

+   - s6.1.1 "_ADR (Address)"

+  - linux kernel code

+  - Arm Base Boot Requirements v1.0

+  - Arm Base System Architecture v1.0

+**/

+

+#include <Library/AcpiLib.h>

+#include <Library/BaseLib.h>

+#include <Library/BaseMemoryLib.h>

+#include <Library/DebugLib.h>

+#include <Library/MemoryAllocationLib.h>

+#include <Protocol/AcpiTable.h>

+

+// Module specific include files.

+#include <AcpiTableGenerator.h>

+#include <ConfigurationManagerObject.h>

+#include <ConfigurationManagerHelper.h>

+#include <Library/AcpiHelperLib.h>

+#include <Library/TableHelperLib.h>

+#include <Library/AmlLib/AmlLib.h>

+#include <Library/SsdtPcieSupportLib.h>

+#include <Protocol/ConfigurationManagerProtocol.h>

+

+#include "SsdtPcieSupportLibPrivate.h"

+

+/** Generate Pci slots devices.

+

+  PCI Firmware Specification - Revision 3.3,

+  s4.8 "Generic ACPI PCI Slot Description" requests to describe the PCI slot

+  used. It should be possible to enumerate them, but this is additional

+  information.

+

+  @param [in]       PciInfo     Pci device information.

+  @param [in]  MappingTable     The mapping table structure.

+  @param [in, out]  PciNode     Pci node to amend.

+

+  @retval EFI_SUCCESS            Success.

+  @retval EFI_INVALID_PARAMETER  Invalid parameter.

+  @retval EFI_OUT_OF_RESOURCES   Failed to allocate memory.

+**/

+EFI_STATUS

+EFIAPI

+GeneratePciSlots (

+  IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO  *PciInfo,

+  IN      CONST MAPPING_TABLE                 *MappingTable,

+  IN  OUT       AML_OBJECT_NODE_HANDLE        PciNode

+  )

+{

+  EFI_STATUS              Status;

+  UINT32                  Index;

+  UINT32                  LastIndex;

+  UINT32                  DeviceId;

+  CHAR8                   AslName[AML_NAME_SEG_SIZE + 1];

+  AML_OBJECT_NODE_HANDLE  DeviceNode;

+

+  ASSERT (MappingTable != NULL);

+  ASSERT (PciNode != NULL);

+

+  // Generic device name is "Dxx".

+  CopyMem (AslName, "Dxx_", AML_NAME_SEG_SIZE + 1);

+

+  LastIndex = MappingTable->LastIndex;

+

+  // There are at most 32 devices on a Pci bus.

+  if (LastIndex >= 32) {

+    ASSERT (0);

+    return EFI_INVALID_PARAMETER;

+  }

+

+  for (Index = 0; Index < LastIndex; Index++) {

+    DeviceId                       = MappingTable->Table[Index];

+    AslName[AML_NAME_SEG_SIZE - 3] = AsciiFromHex (DeviceId & 0xF);

+    AslName[AML_NAME_SEG_SIZE - 2] = AsciiFromHex ((DeviceId >> 4) & 0xF);

+

+    // ASL:

+    // Device (Dxx) {

+    //   Name (_ADR, <address value>)

+    // }

+    Status = AmlCodeGenDevice (AslName, PciNode, &DeviceNode);

+    if (EFI_ERROR (Status)) {

+      ASSERT (0);

+      return Status;

+    }

+

+    /* ACPI 6.4 specification, Table 6.2: "ADR Object Address Encodings"

+       High word-Device #, Low word-Function #. (for example, device 3,

+       function 2 is 0x00030002). To refer to all the functions on a device #,

+       use a function number of FFFF).

+    */

+    Status = AmlCodeGenNameInteger (

+               "_ADR",

+               (DeviceId << 16) | 0xFFFF,

+               DeviceNode,

+               NULL

+               );

+    if (EFI_ERROR (Status)) {

+      ASSERT (0);

+      return Status;

+    }

+

+    // _SUN object is not generated as we don't know which slot will be used.

+  }

+

+  return Status;

+}

+

+/** Add an _OSC template method to the PciNode.

+

+  The _OSC method is provided as an AML blob. The blob is

+  parsed and attached at the end of the PciNode list of variable elements.

+

+  @param [in]       PciInfo     Pci device information.

+  @param [in, out]  PciNode     Pci node to amend.

+

+  @retval EFI_SUCCESS             The function completed successfully.

+  @retval EFI_INVALID_PARAMETER   Invalid parameter.

+  @retval EFI_OUT_OF_RESOURCES    Could not allocate memory.

+**/

+EFI_STATUS

+EFIAPI

+AddOscMethod (

+  IN      CONST CM_ARM_PCI_CONFIG_SPACE_INFO  *PciInfo,

+  IN  OUT   AML_OBJECT_NODE_HANDLE            PciNode

+  )

+{

+  EFI_STATUS                   Status;

+  EFI_STATUS                   Status1;

+  EFI_ACPI_DESCRIPTION_HEADER  *SsdtPcieOscTemplate;

+  AML_ROOT_NODE_HANDLE         OscTemplateRoot;

+  AML_OBJECT_NODE_HANDLE       OscNode;

+

+  ASSERT (PciNode != NULL);

+

+  // Parse the Ssdt Pci Osc Template.

+  SsdtPcieOscTemplate = (EFI_ACPI_DESCRIPTION_HEADER *)

+                        ssdtpcieosctemplate_aml_code;

+

+  OscNode         = NULL;

+  OscTemplateRoot = NULL;

+  Status          = AmlParseDefinitionBlock (

+                      SsdtPcieOscTemplate,

+                      &OscTemplateRoot

+                      );

+  if (EFI_ERROR (Status)) {

+    DEBUG ((

+      DEBUG_ERROR,

+      "ERROR: SSDT-PCI-OSC: Failed to parse SSDT PCI OSC Template."

+      " Status = %r\n",

+      Status

+      ));

+    return Status;

+  }

+

+  Status = AmlFindNode (OscTemplateRoot, "\\_OSC", &OscNode);

+  if (EFI_ERROR (Status)) {

+    goto error_handler;

+  }

+

+  Status = AmlDetachNode (OscNode);

+  if (EFI_ERROR (Status)) {

+    goto error_handler;

+  }

+

+  Status = AmlAttachNode (PciNode, OscNode);

+  if (EFI_ERROR (Status)) {

+    // Free the detached node.

+    AmlDeleteTree (OscNode);

+    goto error_handler;

+  }

+

+error_handler:

+  // Cleanup

+  Status1 = AmlDeleteTree (OscTemplateRoot);

+  if (EFI_ERROR (Status1)) {

+    DEBUG ((

+      DEBUG_ERROR,

+      "ERROR: SSDT-PCI-OSC: Failed to cleanup AML tree."

+      " Status = %r\n",

+      Status1

+      ));

+    // If Status was success but we failed to delete the AML Tree

+    // return Status1 else return the original error code, i.e. Status.

+    if (!EFI_ERROR (Status)) {

+      return Status1;

+    }

+  }

+

+  return Status;

+}

diff --git a/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.inf b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.inf
new file mode 100644
index 0000000000..57fe32369f
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLib.inf
@@ -0,0 +1,30 @@
+## @file

+# Ssdt PCIe Support Library.

+#

+#  Copyright (c) 2021, Arm Limited. All rights reserved.<BR>

+#

+#  SPDX-License-Identifier: BSD-2-Clause-Patent

+##

+

+[Defines]

+  INF_VERSION    = 0x0001001B

+  BASE_NAME      = SsdtPcieSupportLib

+  FILE_GUID      = 510451a0-60b2-446c-b6bf-59cbe4a41782

+  VERSION_STRING = 1.0

+  MODULE_TYPE    = DXE_DRIVER

+  LIBRARY_CLASS  = SsdtPcieSupportLib

+

+[Sources]

+  SsdtPcieSupportLib.c

+  SsdtPcieSupportLibPrivate.h

+  SsdtPcieOscTemplate.asl

+

+[Packages]

+  DynamicTablesPkg/DynamicTablesPkg.dec

+  EmbeddedPkg/EmbeddedPkg.dec

+  MdePkg/MdePkg.dec

+

+[LibraryClasses]

+  AcpiHelperLib

+  AmlLib

+  BaseLib

diff --git a/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLibPrivate.h b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLibPrivate.h
new file mode 100644
index 0000000000..0c070b8c7b
--- /dev/null
+++ b/DynamicTablesPkg/Library/Common/SsdtPcieSupportLib/SsdtPcieSupportLibPrivate.h
@@ -0,0 +1,25 @@
+/** @file

+  SSDT PCIe Support Library private data.

+

+  Copyright (c) 2021, Arm Limited. All rights reserved.<BR>

+  SPDX-License-Identifier: BSD-2-Clause-Patent

+

+  @par Reference(s):

+  - PCI Firmware Specification - Revision 3.0

+  - ACPI 6.4 specification:

+   - s6.2.13 "_PRT (PCI Routing Table)"

+   - s6.1.1 "_ADR (Address)"

+  - linux kernel code

+  - Arm Base Boot Requirements v1.0

+**/

+

+#ifndef SSDT_PCIE_SUPPORT_LIB_PRIVATE_H_

+#define SSDT_PCIE_SUPPORT_LIB_PRIVATE_H_

+

+/** C array containing the compiled AML template.

+    This symbol is defined in the auto generated C file

+    containing the AML bytecode array.

+*/

+extern CHAR8  ssdtpcieosctemplate_aml_code[];

+

+#endif // SSDT_PCIE_SUPPORT_LIB_PRIVATE_H_