OvmfPkg: clone PciHostBridgeLib from MdeModulePkg's Null instance

In this patch we clone "MdeModulePkg/Library/PciHostBridgeLibNull" for
customization under OvmfPkg. Differences relative to a verbatim copy:

- the Null suffix is dropped from file names,
- the UNI file is dropped, together with the corresponding MODULE_UNI_FILE
  reference in the INF file,
- the INF file receives a new FILE_GUID,
- the top comments in the files mention OVMF, not a null instance.

Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Marcel Apfelbaum <marcel@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>

OvmfPkg/Library/PciHostBridgeLib/PciHostBridgeLib.c

@@ -0,0 +1,117 @@
+/** @file
+  OVMF's instance of the PCI Host Bridge Library.
+
+  Copyright (C) 2016, Red Hat, Inc.
+  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+
+  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.
+
+**/
+#include <PiDxe.h>
+#include <Library/PciHostBridgeLib.h>
+#include <Library/DebugLib.h>
+
+GLOBAL_REMOVE_IF_UNREFERENCED
+CHAR16 *mPciHostBridgeLibAcpiAddressSpaceTypeStr[] = {
+  L"Mem", L"I/O", L"Bus"
+};
+
+/**
+  Return all the root bridge instances in an array.
+
+  @param Count  Return the count of root bridge instances.
+
+  @return All the root bridge instances in an array.
+          The array should be passed into PciHostBridgeFreeRootBridges()
+          when it's not used.
+**/
+PCI_ROOT_BRIDGE *
+EFIAPI
+PciHostBridgeGetRootBridges (
+  UINTN *Count
+  )
+{
+  *Count = 0;
+  return NULL;
+}
+
+/**
+  Free the root bridge instances array returned from
+  PciHostBridgeGetRootBridges().
+
+  @param  The root bridge instances array.
+  @param  The count of the array.
+**/
+VOID
+EFIAPI
+PciHostBridgeFreeRootBridges (
+  PCI_ROOT_BRIDGE *Bridges,
+  UINTN           Count
+  )
+{
+  return;
+}
+
+/**
+  Inform the platform that the resource conflict happens.
+
+  @param HostBridgeHandle Handle of the Host Bridge.
+  @param Configuration    Pointer to PCI I/O and PCI memory resource
+                          descriptors. The Configuration contains the resources
+                          for all the root bridges. The resource for each root
+                          bridge is terminated with END descriptor and an
+                          additional END is appended indicating the end of the
+                          entire resources. The resource descriptor field
+                          values follow the description in
+                          EFI_PCI_HOST_BRIDGE_RESOURCE_ALLOCATION_PROTOCOL
+                          .SubmitResources().
+**/
+VOID
+EFIAPI
+PciHostBridgeResourceConflict (
+  EFI_HANDLE                        HostBridgeHandle,
+  VOID                              *Configuration
+  )
+{
+  EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *Descriptor;
+  UINTN                             RootBridgeIndex;
+  DEBUG ((EFI_D_ERROR, "PciHostBridge: Resource conflict happens!\n"));
+
+  RootBridgeIndex = 0;
+  Descriptor = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *) Configuration;
+  while (Descriptor->Desc == ACPI_ADDRESS_SPACE_DESCRIPTOR) {
+    DEBUG ((EFI_D_ERROR, "RootBridge[%d]:\n", RootBridgeIndex++));
+    for (; Descriptor->Desc == ACPI_ADDRESS_SPACE_DESCRIPTOR; Descriptor++) {
+      ASSERT (Descriptor->ResType <
+              (sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr) /
+               sizeof (mPciHostBridgeLibAcpiAddressSpaceTypeStr[0])
+               )
+              );
+      DEBUG ((EFI_D_ERROR, " %s: Length/Alignment = 0x%lx / 0x%lx\n",
+              mPciHostBridgeLibAcpiAddressSpaceTypeStr[Descriptor->ResType],
+              Descriptor->AddrLen, Descriptor->AddrRangeMax
+              ));
+      if (Descriptor->ResType == ACPI_ADDRESS_SPACE_TYPE_MEM) {
+        DEBUG ((EFI_D_ERROR, "     Granularity/SpecificFlag = %ld / %02x%s\n",
+                Descriptor->AddrSpaceGranularity, Descriptor->SpecificFlag,
+                ((Descriptor->SpecificFlag &
+                  EFI_ACPI_MEMORY_RESOURCE_SPECIFIC_FLAG_CACHEABLE_PREFETCHABLE
+                  ) != 0) ? L" (Prefetchable)" : L""
+                ));
+      }
+    }
+    //
+    // Skip the END descriptor for root bridge
+    //
+    ASSERT (Descriptor->Desc == ACPI_END_TAG_DESCRIPTOR);
+    Descriptor = (EFI_ACPI_ADDRESS_SPACE_DESCRIPTOR *)(
+                   (EFI_ACPI_END_TAG_DESCRIPTOR *)Descriptor + 1
+                   );
+  }
+}

OvmfPkg/Library/PciHostBridgeLib/PciHostBridgeLib.inf

@@ -0,0 +1,38 @@
+## @file
+#  OVMF's instance of the PCI Host Bridge Library.
+#
+#  Copyright (C) 2016, Red Hat, Inc.
+#  Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
+#
+#  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.
+#
+#
+##
+
+[Defines]
+  INF_VERSION                    = 0x00010005
+  BASE_NAME                      = PciHostBridgeLib
+  FILE_GUID                      = 9F2BC05E-51EA-4AED-9A3E-7699641734E8
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  LIBRARY_CLASS                  = PciHostBridgeLib
+
+#
+# The following information is for reference only and not required by the build
+# tools.
+#
+#  VALID_ARCHITECTURES           = IA32 X64 IPF EBC
+#
+
+[Sources]
+  PciHostBridgeLib.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec