[PATCH] OvmfPkg/GcdNotifyDxe: Install EFI_GCD_MEMORY_SPACE_NOTIFY_PROTOCOL

[Leo Duran <leo.duran@amd.com>]

On entry, GcdNotifyDxe scans the GCD MemmorySpace map and produces this
protocol to get notifications from GCD on MemorySpace Add/Remove operations.

This patch illustrates how OvmfPkg could take actions on GCD notifications.
For example: updating the SEV mask on page-table entries for MMIO ranges.

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Feng Tian <feng.tian@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Brijesh Singh <brijesh.ksingh@gmail.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Leo Duran <leo.duran@amd.com>
---
 OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.c   | 148 ++++++++++++++++++++++++++++++++++
 OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf |  44 ++++++++++
 OvmfPkg/OvmfPkgIa32X64.dsc            |   2 +
 OvmfPkg/OvmfPkgIa32X64.fdf            |   3 +
 4 files changed, 197 insertions(+)
 create mode 100644 OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.c
 create mode 100644 OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf

diff --git a/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.c b/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.c
new file mode 100644
index 0000000..1b54584
--- /dev/null
+++ b/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.c
@@ -0,0 +1,148 @@
+/** @file
+
+  GCD Memory Space Map notification protocol handler.
+
+  Copyright (c) 2017, AMD Inc. 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/BaseLib.h>
+#include <Library/UefiLib.h>
+#include <Library/UefiDriverEntryPoint.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/DebugLib.h>
+
+#include <Protocol/GcdMemorySpaceNotify.h>
+
+//
+// GCD Memory Space Map notification protocol
+//
+STATIC EFI_GCD_MEMORY_SPACE_NOTIFY_PROTOCOL  mGcdMemorySpaceNotifyProtocol;
+
+///
+/// Lookup table used to print GCD Memory Space Map
+///
+GLOBAL_REMOVE_IF_UNREFERENCED CONST CHAR8 *mGcdMemoryTypeNames[] = {
+  "EfiGcdMemoryTypeNonExistent",
+  "EfiGcdMemoryTypeReserved",
+  "EfiGcdMemoryTypeSystemMemory",
+  "EfiGcdMemoryTypeMemoryMappedIo",
+  "EfiGcdMemoryTypePersistentMemory",
+  "EfiGcdMemoryTypeMoreReliable",
+  "EfiGcdMemoryTypeMaximum"
+};
+
+
+/**
+Notify on: Add a segment of memory to GCD map.
+
+@param  GcdMemoryType          Memory type of the segment.
+@param  BaseAddress            Base address of the segment.
+@param  Length                 Length of the segment.
+@param  Capabilities           Alterable attributes of the segment.
+
+**/
+STATIC
+VOID
+EFIAPI
+GcdMemorySpaceAddNotify (
+IN EFI_GCD_MEMORY_TYPE   GcdMemoryType,
+IN EFI_PHYSICAL_ADDRESS  BaseAddress,
+IN UINT64                Length,
+IN UINT64                Capabilities
+)
+{
+  DEBUG ((EFI_D_INFO, "%a()\n", __FUNCTION__));
+
+  if (GcdMemoryType >= EfiGcdMemoryTypeNonExistent && GcdMemoryType <= EfiGcdMemoryTypeMaximum) {
+    DEBUG ((EFI_D_INFO, " GcdMemoryType = 0x%X (%a)\n", GcdMemoryType, mGcdMemoryTypeNames[GcdMemoryType]));
+    DEBUG ((EFI_D_INFO, " BaseAddress   = 0x%p\n", BaseAddress));
+    DEBUG ((EFI_D_INFO, " Length        = 0x%lX\n", Length));
+
+    if (GcdMemoryType == EfiGcdMemoryTypeMemoryMappedIo) {
+      DEBUG ((EFI_D_INFO, " MMIO: Start = 0x%p, Length = 0x%lX\n", BaseAddress, Length));
+    }
+  }
+  else {
+    DEBUG ((EFI_D_INFO, " Invalid GcdMemoryType = 0x%X\n", GcdMemoryType));
+  }
+}
+
+
+/**
+Notify on: Remove a segment of memory to GCD map.
+
+@param  BaseAddress            Base address of the segment.
+@param  Length                 Length of the segment.
+
+**/
+STATIC
+VOID
+EFIAPI
+GcdMemorySpaceRemoveNotify (
+IN EFI_PHYSICAL_ADDRESS  BaseAddress,
+IN UINT64                Length
+)
+{
+  DEBUG ((EFI_D_INFO, "%a()\n", __FUNCTION__));
+  DEBUG ((EFI_D_INFO, " BaseAddress = 0x%p\n", BaseAddress));
+  DEBUG ((EFI_D_INFO, " Length = 0x%lX\n", Length));
+}
+
+
+EFI_STATUS
+EFIAPI
+GcdNotifyDxeEntry (
+  IN EFI_HANDLE         ImageHandle,
+  IN EFI_SYSTEM_TABLE   *SystemTable
+  )
+{
+  EFI_GCD_MEMORY_SPACE_DESCRIPTOR  *MemorySpaceMap;
+  UINTN                            NumEntries;
+  UINTN                            Index;
+  EFI_STATUS                       Status;
+  EFI_HANDLE                       Handle;
+
+  DEBUG((EFI_D_INFO, "%a - ENTRY\n", __FUNCTION__));
+
+  //
+  // Iterate through the current MemorySpace Map 
+  //
+  MemorySpaceMap = NULL;
+  Status = gDS->GetMemorySpaceMap (&NumEntries, &MemorySpaceMap);
+  ASSERT_EFI_ERROR (Status);
+
+  for (Index = 0; Index < NumEntries; ++Index) {
+    if (MemorySpaceMap[Index].GcdMemoryType == EfiGcdMemoryTypeMemoryMappedIo) {
+      DEBUG ((DEBUG_INFO, " MMIO: Start = 0x%p, Length = 0x%lX\n",
+        MemorySpaceMap[Index].BaseAddress, MemorySpaceMap[Index].Length));
+    }  
+  }
+ 
+  //
+  // Install GCD Memory Space Map notification protocol
+  //
+  mGcdMemorySpaceNotifyProtocol.MemorySpaceAddNotify = GcdMemorySpaceAddNotify;
+  mGcdMemorySpaceNotifyProtocol.MemorySpaceRemoveNotify = GcdMemorySpaceRemoveNotify;
+  Handle = NULL;
+  Status = gBS->InstallProtocolInterface (
+    &Handle,
+    &gEfiGcdMemorySpaceNotifyProtocolGuid,
+    EFI_NATIVE_INTERFACE,
+    &mGcdMemorySpaceNotifyProtocol);
+  ASSERT_EFI_ERROR (Status);
+
+  DEBUG((EFI_D_INFO, "%a - EXIT (Status = %r)\n", __FUNCTION__, Status));
+  return Status;
+}
diff --git a/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf b/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf
new file mode 100644
index 0000000..a4c8445
--- /dev/null
+++ b/OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf
@@ -0,0 +1,44 @@
+#/** @file
+#
+#  Component description file for GcdNotifyDxe module
+#
+#  Copyright (c) 2017, AMD Inc. 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                      = GcdNotifyDxe
+  FILE_GUID                      = 2ec9da37-ee35-4de9-86c5-6d9a81dc38a7
+  MODULE_TYPE                    = DXE_DRIVER
+  VERSION_STRING                 = 1.0
+  ENTRY_POINT                    = GcdNotifyDxeEntry
+
+[Sources]
+  GcdNotifyDxe.c
+
+[Packages]
+  MdePkg/MdePkg.dec
+  MdeModulePkg/MdeModulePkg.dec
+
+[LibraryClasses]
+  BaseLib
+  UefiLib
+  UefiDriverEntryPoint
+  UefiBootServicesTableLib
+  DxeServicesTableLib
+  DebugLib
+
+[Protocols]
+  gEfiGcdMemorySpaceNotifyProtocolGuid    ## PRODUCES
+
+[Depex]
+  TRUE
diff --git a/OvmfPkg/OvmfPkgIa32X64.dsc b/OvmfPkg/OvmfPkgIa32X64.dsc
index 71ac62f..441d7cc 100644
--- a/OvmfPkg/OvmfPkgIa32X64.dsc
+++ b/OvmfPkg/OvmfPkgIa32X64.dsc
@@ -3,6 +3,7 @@
 #
 #  Copyright (c) 2006 - 2017, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
+#  Copyright (c) 2017, AMD Inc. All rights reserved.<BR>
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -798,6 +799,7 @@
 !endif
 
   OvmfPkg/PlatformDxe/Platform.inf
+  OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf
 
 !if $(SMM_REQUIRE) == TRUE
   OvmfPkg/SmmAccess/SmmAccess2Dxe.inf
diff --git a/OvmfPkg/OvmfPkgIa32X64.fdf b/OvmfPkg/OvmfPkgIa32X64.fdf
index 5233314..71b118a 100644
--- a/OvmfPkg/OvmfPkgIa32X64.fdf
+++ b/OvmfPkg/OvmfPkgIa32X64.fdf
@@ -3,6 +3,7 @@
 #
 #  Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
 #  (C) Copyright 2016 Hewlett Packard Enterprise Development LP<BR>
+#  Copyright (c) 2017, AMD Inc. All rights reserved.<BR>
 #
 #  This program and the accompanying materials
 #  are licensed and made available under the terms and conditions of the BSD License
@@ -193,6 +194,7 @@ APRIORI DXE {
 !if $(SMM_REQUIRE) == FALSE
   INF  OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FvbServicesRuntimeDxe.inf
 !endif
+  INF  OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf
 }
 
 #
@@ -351,6 +353,7 @@ INF  RuleOverride=CSM OvmfPkg/Csm/Csm16/Csm16.inf
 INF  OvmfPkg/QemuVideoDxe/QemuVideoDxe.inf
 INF  OvmfPkg/VirtioGpuDxe/VirtioGpu.inf
 INF  OvmfPkg/PlatformDxe/Platform.inf
+INF  OvmfPkg/GcdNotifyDxe/GcdNotifyDxe.inf
 
 !if $(SMM_REQUIRE) == TRUE
 INF  OvmfPkg/SmmAccess/SmmAccess2Dxe.inf
-- 
2.7.4