[PATCH V3 1/6] OvmfPkg/AcpiPlatformDxe: Remove QEMU_ACPI_TABLE_NOTIFY_PROTOCOL

["Min Xu" <min.m.xu@intel.com>]

From: Min M Xu <min.m.xu@intel.com>

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=4237

The QEMU_ACPI_TABLE_NOTIFY_PROTOCOL structure is superfluous because NULL
protocol interfaces have been used in edk2 repeatedly. A protocol instance
can exist in the protocol database with a NULL associated interface.
Therefore the QEMU_ACPI_TABLE_NOTIFY_PROTOCOL type, the
"QemuAcpiTableNotify.h" header, and the "mAcpiNotifyProtocol" global
variable can be removed.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Sebastien Boeuf <sebastien.boeuf@intel.com>
Reported-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
---
 OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c         |  7 ++---
 OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c       |  6 ++---
 .../Include/Protocol/QemuAcpiTableNotify.h    | 27 -------------------
 3 files changed, 4 insertions(+), 36 deletions(-)
 delete mode 100644 OvmfPkg/Include/Protocol/QemuAcpiTableNotify.h

diff --git a/OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c b/OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c
index cbe8bb9b0c75..ad39e4253478 100644
--- a/OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c
+++ b/OvmfPkg/AcpiPlatformDxe/CloudHvAcpi.c
@@ -15,15 +15,12 @@
 #include <Library/PcdLib.h>                               // PcdGet32()
 #include <Library/HobLib.h>                               // GetFirstGuidHob(), GetNextGuidHob()
 #include <Library/UefiBootServicesTableLib.h>             // gBS
-
 #include <Protocol/AcpiSystemDescriptionTable.h>
 #include <Protocol/AcpiTable.h>
-#include <Protocol/QemuAcpiTableNotify.h>                 // QEMU_ACPI_TABLE_NOTIFY_PROTOCOL
 
 #include "AcpiPlatform.h"
 
-EFI_HANDLE                       mChAcpiHandle = NULL;
-QEMU_ACPI_TABLE_NOTIFY_PROTOCOL  mChAcpiNotifyProtocol;
+EFI_HANDLE  mChAcpiHandle = NULL;
 
 EFI_STATUS
 EFIAPI
@@ -96,7 +93,7 @@ InstallCloudHvTablesTdx (
          &mChAcpiHandle,
          &gQemuAcpiTableNotifyProtocolGuid,
          EFI_NATIVE_INTERFACE,
-         &mChAcpiNotifyProtocol
+         NULL
          );
 
   return EFI_SUCCESS;
diff --git a/OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c b/OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c
index c8dee17c13e6..1a3852904df9 100644
--- a/OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c
+++ b/OvmfPkg/AcpiPlatformDxe/QemuFwCfgAcpi.c
@@ -19,10 +19,8 @@
 #include <Library/QemuFwCfgS3Lib.h>           // QemuFwCfgS3Enabled()
 #include <Library/UefiBootServicesTableLib.h> // gBS
 
-#include <Protocol/QemuAcpiTableNotify.h>
 #include "AcpiPlatform.h"
-EFI_HANDLE                       mQemuAcpiHandle = NULL;
-QEMU_ACPI_TABLE_NOTIFY_PROTOCOL  mAcpiNotifyProtocol;
+EFI_HANDLE  mQemuAcpiHandle = NULL;
 
 //
 // The user structure for the ordered collection that will track the fw_cfg
@@ -1284,7 +1282,7 @@ UninstallAcpiTables:
            &mQemuAcpiHandle,
            &gQemuAcpiTableNotifyProtocolGuid,
            EFI_NATIVE_INTERFACE,
-           &mAcpiNotifyProtocol
+           NULL
            );
   }
 
diff --git a/OvmfPkg/Include/Protocol/QemuAcpiTableNotify.h b/OvmfPkg/Include/Protocol/QemuAcpiTableNotify.h
deleted file mode 100644
index a3dd2fc1dc91..000000000000
--- a/OvmfPkg/Include/Protocol/QemuAcpiTableNotify.h
+++ /dev/null
@@ -1,27 +0,0 @@
-/** @file
-
-  SPDX-License-Identifier: BSD-2-Clause-Patent
-
-**/
-
-#ifndef QEMU_ACPI_TABLE_NOTIFY_H_
-#define QEMU_ACPI_TABLE_NOTIFY_H_
-
-#define QEMU_ACPI_TABLE_NOTIFY_GUID \
-  { 0x928939b2, 0x4235, 0x462f, { 0x95, 0x80, 0xf6, 0xa2, 0xb2, 0xc2, 0x1a, 0x4f } };
-
-///
-/// Forward declaration
-///
-typedef struct _QEMU_ACPI_TABLE_NOTIFY_PROTOCOL QEMU_ACPI_TABLE_NOTIFY_PROTOCOL;
-
-///
-/// Protocol structure
-///
-struct _QEMU_ACPI_TABLE_NOTIFY_PROTOCOL {
-  UINT8    Notify;
-};
-
-extern EFI_GUID  gQemuAcpiTableNotifyProtocolGuid;
-
-#endif
-- 
2.29.2.windows.2