[PATCH v4 0/2] *** EFI_MM_COMMUNICATION_PROTOCOL ***

[PATCH v4 0/2] *** EFI_MM_COMMUNICATION_PROTOCOL ***

[Supreeth Venkatesh]

***
PI v1.5 Specification Volume 4 defines Management Mode Core Interface
and defines EFI_MM_COMMUNICATION_PROTOCOL. This protocol provides a
means of communicating between drivers outside of MM and MMI
handlers inside of MM.

EFI_MM_COMMUNICATION_PROTOCOL
Summary
  This protocol provides a means of communicating between drivers outside of MM and MMI
  handlers inside of MM.

GUID
  #define EFI_MM_COMMUNICATION_PROTOCOL_GUID \
  { 0xc68ed8e2, 0x9dc6, 0x4cbd, 0x9d, 0x94, 0xdb, 0x65, 0xac, 0xc5, 0xc3, 0x32 }

Prototype
  typedef struct _EFI_MM_COMMUNICATION_PROTOCOL {
  EFI_MM_COMMUNICATE Communicate;
  } EFI_MM_COMMUNICATION_PROTOCOL;

Members
Communicate
  Sends/receives a message for a registered handler. See the Communicate()
  function description.

Description
  This protocol provides runtime services for communicating between DXE drivers and a registered
  MMI handler.

EFI_MM_COMMUNICATION_PROTOCOL.Communicate()
Summary
  Communicates with a registered handler.

Prototype
  typedef
  EFI_STATUS
  (EFIAPI *EFI_MM_COMMUNICATE) (
  IN CONST EFI_MM_COMMUNICATION_PROTOCOL *This,
  IN OUT VOID *CommBuffer,
  IN OUT UINTN *CommSize OPTIONAL
  );

Parameters
  This - The EFI_MM_COMMUNICATION_PROTOCOL instance.
  CommBuffer - Pointer to the buffer to convey into MMRAM.
  CommSize - The size of the data buffer being passed in. On exit, the size of data being returned.
                     Zero if the handler does not wish to reply with any data. This parameter is optional
                     and may be NULL.

Description
  This function provides a service to send and receive messages from a registered UEFI service. The EFI_MM_COMMUNICATION_PROTOCOL driver is responsible for doing any of the
  copies such that the data lives in boot-service-accessible RAM.
  A given implementation of the EFI_MM_COMMUNICATION_PROTOCOL may choose to use the EFI_MM_CONTROL_PROTOCOL for effecting the mode transition, or it may use some other method.
  The agent invoking the communication interface at runtime may be virtually mapped. The MM infrastructure code and handlers, on the other hand, execute in physical mode. As a result, the non-MM agent,
  which may be executing in the virtual-mode OS context (as a result of an OS invocation of the UEFI SetVirtualAddressMap() service), should use a contiguous memory buffer with a physical address before
  invoking this service. If the virtual address of the buffer is used, the MM Driver may not know how to do the appropriate virtual-to-physical conversion.
  To avoid confusion in interpreting frames, the CommunicateBuffer parameter should always begin with EFI_MM_COMMUNICATE_HEADER, which is defined in Related Definitions below.
  The header data is mandatory for messages sent into the MM agent.
  If the CommSize parameter is omitted the MessageLength field in the EFI_MM_COMMUNICATE_HEADER,
  in conjunction with the size of the header itself, can be used to ascertain the total size of the communication payload.
  If the MessageLength is zero, or too large for the MM implementation to manage, the MM implementation must update the MessageLength to reflect the size of the Data buffer that it can tolerate.
  If the CommSize parameter is passed into the call, but the integer it points to, has a value of 0, then this must be updated to reflect the maximum size of the CommBuffer that the implementation can tolerate.
  Once inside of MM, the MM infrastructure will call all registered handlers with the same HandlerType as the GUID specified by HeaderGuid and the CommBuffer pointing to Data.
  This function is not reentrant.
  The standard header is used at the beginning of the EFI_MM_INITIALIATION_HEADER structure during MM initialization. See "Related Definitions" below for more information.

Related Definitions
  typedef struct {
  EFI_GUID HeaderGuid;
  UINTN MessageLength;
  UINT8 Data[ANYSIZE_ARRAY];
  } EFI_MM_COMMUNICATE_HEADER;

  HeaderGuid - Allows for disambiguation of the message format. Type EFI_GUID is defined in
                       InstallProtocolInterface() in the UEFI Specification.
  MessageLength - Describes the size of Data (in bytes) and does not include the size of the header.
  Data - Designates an array of bytes that is MessageLength in size.

Status Codes Returned
  EFI_SUCCESS - The message was successfully posted.
  EFI_INVALID_PARAMETER - The buffer was NULL.
  EFI_BAD_BUFFER_SIZE - The buffer is too large for the MM implementation. If this error is
                                           returned, the MessageLength field in the CommBuffer
                                           header or the integer pointed by CommSize, are updated to reflect
                                           the maximum payload size the implementation can accommodate.
                                           See the function description above for more details.
  EFI_ACCESS_DENIED - The CommunicateBuffer parameter or CommSize
                                        parameter, if not omitted, are in address range that cannot be
                                        accessed by the MM environment.

This patchset implements it on AARCH64 Platform.
The PI concept of a Standalone MM environment is intialized during the
SEC phase in AARCH64 Platform i.e., On AARCH64, this environment is initialized
and locked down in the secure world.
This driver enables communication with the MM environment during boot and
runtime.
***
Changes Since v3:
(*) Review Comments from Meenakshi.
***
Changes Since v2:
(*) Review Comments from Ard, Udit.
(*) Added Cleanup code.
(*) Combined .inf and .c files in a single patch.
***
Changes Since v1:
(*) Update Review Comments from Ard, Jan, Achin.
(*) Reword Commit subject for the patches in the set to convey more meaningful summary. 
***
Supreeth Venkatesh (2):
  ArmPkg: Add PCDs needed for MM communication driver.
  ArmPkg/Drivers: Add EFI_MM_COMMUNICATION_PROTOCOL DXE driver.

 ArmPkg/ArmPkg.dec                                  |   3 +
 .../Drivers/MmCommunicationDxe/MmCommunication.c   | 340 +++++++++++++++++++++
 .../Drivers/MmCommunicationDxe/MmCommunication.inf |  50 +++
 3 files changed, 393 insertions(+)
 create mode 100644 ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
 create mode 100644 ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf

-- 
2.14.1

[PATCH v4 1/2] ArmPkg: Add PCDs needed for MM communication driver.

[Supreeth Venkatesh]

This patch defines PCDs to describe the base address and size of
communication buffer between normal world (uefi) and standalone MM
environment in the secure world.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Achin Gupta <achin.gupta@arm.com>
Signed-off-by: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
---
 ArmPkg/ArmPkg.dec | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/ArmPkg/ArmPkg.dec b/ArmPkg/ArmPkg.dec
index 5dbd019e29..4876bcef81 100644
--- a/ArmPkg/ArmPkg.dec
+++ b/ArmPkg/ArmPkg.dec
@@ -221,6 +221,9 @@
   gArmTokenSpaceGuid.PcdSystemMemoryBase|0|UINT64|0x00000029
   gArmTokenSpaceGuid.PcdSystemMemorySize|0|UINT64|0x0000002A
 
+  gArmTokenSpaceGuid.PcdMmBufferBase|0|UINT64|0x00000045
+  gArmTokenSpaceGuid.PcdMmBufferSize|0|UINT64|0x00000046
+
 [PcdsFixedAtBuild.common, PcdsDynamic.common]
   #
   # ARM Architectural Timer
-- 
2.14.1

[PATCH v4 2/2] ArmPkg/Drivers: Add EFI_MM_COMMUNICATION_PROTOCOL DXE driver.

[Supreeth Venkatesh]

PI v1.5 Specification Volume 4 defines Management Mode Core Interface
and defines EFI_MM_COMMUNICATION_PROTOCOL. This protocol provides a
means of communicating between drivers outside of MM and MMI
handlers inside of MM.

This patch implements the EFI_MM_COMMUNICATION_PROTOCOL DXE runtime
driver for AARCH64 platforms. It uses SMCs allocated from the standard
SMC range defined in DEN0060A_ARM_MM_Interface_Specification.pdf
to communicate with the standalone MM environment in the secure world.

This patch also adds the MM Communication driver (.inf) file to
define entry point for this driver and other compile
related information the driver needs.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Achin Gupta <achin.gupta@arm.com>
Signed-off-by: Supreeth Venkatesh <supreeth.venkatesh@arm.com>
---
 .../Drivers/MmCommunicationDxe/MmCommunication.c   | 340 +++++++++++++++++++++
 .../Drivers/MmCommunicationDxe/MmCommunication.inf |  50 +++
 2 files changed, 390 insertions(+)
 create mode 100644 ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
 create mode 100644 ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf

diff --git a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
new file mode 100644
index 0000000000..9b42def425
--- /dev/null
+++ b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.c
@@ -0,0 +1,340 @@
+/** @file
+
+  Copyright (c) 2016-2017, ARM Limited. All rights reserved.
+
+  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 <Library/ArmLib.h>
+#include <Library/ArmSmcLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/DxeServicesTableLib.h>
+#include <Library/HobLib.h>
+#include <Library/PcdLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+#include <Protocol/MmCommunication.h>
+
+#include <IndustryStandard/ArmStdSmc.h>
+
+//
+// Address, Length of the pre-allocated buffer for communication with the secure
+// world.
+//
+STATIC ARM_MEMORY_REGION_DESCRIPTOR  mNsCommBuffMemRegion;
+
+// Notification event when virtual address map is set.
+STATIC EFI_EVENT  mSetVirtualAddressMapEvent;
+
+//
+// Handle to install the MM Communication Protocol
+//
+STATIC EFI_HANDLE  mMmCommunicateHandle;
+
+/**
+  Communicates with a registered handler.
+
+  This function provides an interface to send and receive messages to the
+  Standalone MM environment on behalf of UEFI services.  This function is part
+  of the MM Communication Protocol that may be called in physical mode prior to
+  SetVirtualAddressMap() and in virtual mode after SetVirtualAddressMap().
+
+  @param[in]      This                The EFI_MM_COMMUNICATION_PROTOCOL
+                                      instance.
+  @param[in, out] CommBuffer          A pointer to the buffer to convey
+                                      into MMRAM.
+  @param[in, out] CommSize            The size of the data buffer being
+                                      passed in. This is optional.
+
+  @retval EFI_SUCCESS                 The message was successfully posted.
+  @retval EFI_INVALID_PARAMETER       The CommBuffer was NULL.
+  @retval EFI_BAD_BUFFER_SIZE         The buffer size is incorrect for the MM
+                                      implementation. If this error is
+                                      returned, the MessageLength field in
+                                      the CommBuffer header or the integer
+                                      pointed by CommSize are updated to reflect
+                                      the maximum payload size the
+                                      implementation can accommodate.
+  @retval EFI_ACCESS_DENIED           The CommunicateBuffer parameter
+                                      or CommSize parameter, if not omitted,
+                                      are in address range that cannot be
+                                      accessed by the MM environment
+**/
+STATIC
+EFI_STATUS
+EFIAPI
+MmCommunicationCommunicate (
+  IN CONST EFI_MM_COMMUNICATION_PROTOCOL  *This,
+  IN OUT VOID                             *CommBuffer,
+  IN OUT UINTN                            *CommSize OPTIONAL
+  )
+{
+  EFI_MM_COMMUNICATE_HEADER   *CommunicateHeader;
+  ARM_SMC_ARGS                CommunicateSmcArgs;
+  EFI_STATUS                  Status;
+  UINTN                       BufferSize;
+
+  CommunicateHeader = CommBuffer;
+  Status = EFI_ACCESS_DENIED;
+  BufferSize = 0;
+
+  ZeroMem (&CommunicateSmcArgs, sizeof (ARM_SMC_ARGS));
+
+  //
+  // Check parameters
+  //
+  if (CommBuffer == NULL) {
+    return EFI_INVALID_PARAMETER;
+  }
+
+  // If the length of the CommBuffer is 0 then return the expected length.
+  if (CommSize) {
+    if (*CommSize == 0) {
+      *CommSize = mNsCommBuffMemRegion.Length;
+      return EFI_BAD_BUFFER_SIZE;
+    }
+    //
+    // CommSize must hold HeaderGuid and MessageLength
+    //
+    if (*CommSize < sizeof (EFI_MM_COMMUNICATE_HEADER)) {
+        return EFI_INVALID_PARAMETER;
+    }
+    BufferSize = *CommSize;
+  } else {
+    BufferSize = CommunicateHeader->MessageLength +
+                 sizeof (CommunicateHeader->HeaderGuid) +
+                 sizeof (CommunicateHeader->MessageLength);
+  }
+
+  //
+  // If the buffer size is 0 or greater than what can be tolerated by the MM
+  // environment then return the expected size.
+  //
+  if ((BufferSize == 0) ||
+      (BufferSize > mNsCommBuffMemRegion.Length)) {
+    CommunicateHeader->MessageLength = mNsCommBuffMemRegion.Length -
+                                       sizeof (CommunicateHeader->HeaderGuid) -
+                                       sizeof (CommunicateHeader->MessageLength);
+    return EFI_BAD_BUFFER_SIZE;
+  }
+
+  // SMC Function ID
+  CommunicateSmcArgs.Arg0 = ARM_SMC_ID_MM_COMMUNICATE_AARCH64;
+
+  // Reserved for Future. Must be Zero.
+  CommunicateSmcArgs.Arg1 = 0;
+
+  if (mNsCommBuffMemRegion.VirtualBase) {
+    CopyMem ((VOID *)mNsCommBuffMemRegion.VirtualBase, CommBuffer, BufferSize);
+  } else {
+    return EFI_ACCESS_DENIED;
+  }
+
+  // For the SMC64 version, this parameter is a 64-bit Physical Address (PA)
+  // or Intermediate Physical Address (IPA).
+  // For the SMC32 version, this parameter is a 32-bit PA or IPA.
+  CommunicateSmcArgs.Arg2 = (UINTN)mNsCommBuffMemRegion.PhysicalBase;
+
+  // comm_size_address is a PA or an IPA that holds the size of the
+  // communication buffer being passed in. This parameter is optional
+  // and can be omitted by passing a zero.
+  // ARM does not recommend using it since this might require the
+  // implementation to create a separate memory mapping for the parameter.
+  // ARM recommends storing the buffer size in the buffer itself.
+  CommunicateSmcArgs.Arg3 = 0;
+
+  // Call the Standalone MM environment.
+  ArmCallSmc (&CommunicateSmcArgs);
+
+  switch (CommunicateSmcArgs.Arg0) {
+  case ARM_SMC_MM_RET_SUCCESS:
+    // On exit, the size of data being returned is inferred from
+    // CommSize or MessageLength + Header.
+    CopyMem (CommBuffer,
+             (const VOID *)mNsCommBuffMemRegion.VirtualBase,
+             BufferSize);
+    Status = EFI_SUCCESS;
+    break;
+
+  case ARM_SMC_MM_RET_NOT_SUPPORTED:
+  case ARM_SMC_MM_RET_INVALID_PARAMS:
+    Status = EFI_INVALID_PARAMETER;
+    break;
+
+  case ARM_SMC_MM_RET_DENIED:
+    Status = EFI_ACCESS_DENIED;
+    break;
+
+  case ARM_SMC_MM_RET_NO_MEMORY:
+    // Unexpected error since the CommSize was checked for zero length
+    // prior to issuing the SMC
+  default:
+    Status = EFI_ACCESS_DENIED;
+    ASSERT (0);
+  }
+
+  return Status;
+}
+
+//
+// MM Communication Protocol instance
+//
+EFI_MM_COMMUNICATION_PROTOCOL  mMmCommunication = {
+  MmCommunicationCommunicate
+};
+
+/**
+  Notification callback on SetVirtualAddressMap event.
+
+  This function notifies the MM communication protocol interface on
+  SetVirtualAddressMap event and converts pointers used in this driver
+  from physical to virtual address.
+
+  @param  Event          SetVirtualAddressMap event.
+  @param  Context        A context when the SetVirtualAddressMap triggered.
+
+  @retval EFI_SUCCESS    The function executed successfully.
+  @retval Other          Some error occurred when executing this function.
+
+**/
+STATIC
+VOID
+EFIAPI
+NotifySetVirtualAddressMap (
+  IN EFI_EVENT  Event,
+  IN VOID      *Context
+  )
+{
+  EFI_STATUS  Status;
+
+  Status = gRT->ConvertPointer (EFI_OPTIONAL_PTR,
+                                (VOID **)&mNsCommBuffMemRegion.VirtualBase
+                               );
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "NotifySetVirtualAddressMap():"
+            " Unable to convert MM runtime pointer. Status:0x%r\n", Status));
+  }
+
+}
+
+/**
+  The Entry Point for MM Communication
+
+  This function installs the MM communication protocol interface and finds out
+  what type of buffer management will be required prior to invoking the
+  communication SMC.
+
+  @param  ImageHandle    The firmware allocated handle for the EFI image.
+  @param  SystemTable    A pointer to the EFI System Table.
+
+  @retval EFI_SUCCESS    The entry point is executed successfully.
+  @retval Other          Some error occurred when executing this entry point.
+
+**/
+EFI_STATUS
+EFIAPI
+MmCommunicationInitialize (
+  IN EFI_HANDLE         ImageHandle,
+  IN EFI_SYSTEM_TABLE  *SystemTable
+  )
+{
+  EFI_STATUS                 Status;
+
+  mNsCommBuffMemRegion.PhysicalBase = PcdGet64 (PcdMmBufferBase);
+
+  mNsCommBuffMemRegion.Length = PcdGet64 (PcdMmBufferSize);
+
+  if (mNsCommBuffMemRegion.PhysicalBase == 0) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicateInitialize: "
+            "Invalid MM Buffer Base Address.\n"));
+    goto ReturnErrorStatus;
+  }
+  // During boot , Virtual and Physical are same
+  mNsCommBuffMemRegion.VirtualBase = mNsCommBuffMemRegion.PhysicalBase;
+
+  if (mNsCommBuffMemRegion.Length == 0) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicateInitialize: "
+            "Maximum Buffer Size is zero.\n"));
+    goto ReturnErrorStatus;
+  }
+
+  Status = gDS->AddMemorySpace (EfiGcdMemoryTypeSystemMemory,
+                                mNsCommBuffMemRegion.PhysicalBase,
+                                mNsCommBuffMemRegion.Length,
+                                EFI_MEMORY_WB |
+                                EFI_MEMORY_XP |
+                                EFI_MEMORY_RUNTIME);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicateInitialize: "
+            "Failed to add MM-NS Buffer Memory Space\n"));
+    goto ReturnErrorStatus;
+  }
+
+  Status = gDS->SetMemorySpaceAttributes (mNsCommBuffMemRegion.PhysicalBase,
+                                          mNsCommBuffMemRegion.Length,
+                                          EFI_MEMORY_WB | EFI_MEMORY_XP);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicateInitialize: "
+            "Failed to set MM-NS Buffer Memory attributes\n"));
+    goto CleanAddedMemorySpace;
+  }
+
+  Status = gBS->AllocatePages (AllocateAddress,
+                               EfiRuntimeServicesData,
+                               EFI_SIZE_TO_PAGES (mNsCommBuffMemRegion.Length),
+                               &mNsCommBuffMemRegion.PhysicalBase);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicateInitialize: "
+            "Failed to allocate MM-NS Buffer Memory Space\n"));
+    goto CleanAddedMemorySpace;
+  }
+
+  // Install the communication protocol
+  Status = gBS->InstallProtocolInterface (&mMmCommunicateHandle,
+                                          &gEfiMmCommunicationProtocolGuid,
+                                          EFI_NATIVE_INTERFACE,
+                                          &mMmCommunication);
+  if (EFI_ERROR (Status)) {
+    DEBUG ((DEBUG_ERROR, "MmCommunicationInitialize: "
+            "Failed to install MM communication protocol\n"));
+    goto CleanAllocatedPages;
+  }
+
+  // Register notification callback when  virtual address is associated
+  // with the physical address.
+  // Create a Set Virtual Address Map event.
+  //
+  Status = gBS->CreateEvent (EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE,  // Type
+                             TPL_NOTIFY,                         // NotifyTpl
+                             NotifySetVirtualAddressMap,         // NotifyFunction
+                             NULL,                               // NotifyContext
+                             &mSetVirtualAddressMapEvent         // Event
+                            );
+  if (Status == EFI_SUCCESS) {
+    return Status;
+  }
+
+  gBS->UninstallProtocolInterface (mMmCommunicateHandle,
+                                   &gEfiMmCommunicationProtocolGuid,
+                                   &mMmCommunication);
+
+CleanAllocatedPages:
+  gBS->FreePages (mNsCommBuffMemRegion.PhysicalBase,
+                  EFI_SIZE_TO_PAGES (mNsCommBuffMemRegion.Length));
+
+CleanAddedMemorySpace:
+  gDS->RemoveMemorySpace (mNsCommBuffMemRegion.PhysicalBase,
+                          mNsCommBuffMemRegion.Length);
+
+ReturnErrorStatus:
+  return EFI_INVALID_PARAMETER;
+}
diff --git a/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
new file mode 100644
index 0000000000..d39ee5fdd7
--- /dev/null
+++ b/ArmPkg/Drivers/MmCommunicationDxe/MmCommunication.inf
@@ -0,0 +1,50 @@
+#/** @file
+#
+#  DXE MM Communicate driver
+#
+#  Copyright (c) 2016 - 2017, ARM Limited. All rights reserved.
+#
+#  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                    = 0x0001001A
+  BASE_NAME                      = ArmMmCommunication
+  FILE_GUID                      = 09EE81D3-F15E-43F4-85B4-CB9873DA5D6B
+  MODULE_TYPE                    = DXE_RUNTIME_DRIVER
+  VERSION_STRING                 = 1.0
+
+  ENTRY_POINT                    = MmCommunicationInitialize
+
+[Sources.Common]
+  MmCommunication.c
+
+[Packages]
+  ArmPkg/ArmPkg.dec
+  MdePkg/MdePkg.dec
+
+[LibraryClasses]
+  ArmLib
+  ArmSmcLib
+  BaseMemoryLib
+  DebugLib
+  DxeServicesTableLib
+  HobLib
+  UefiDriverEntryPoint
+
+[Protocols]
+  gEfiMmCommunicationProtocolGuid              ## PRODUCES
+
+[Pcd.common]
+  gArmTokenSpaceGuid.PcdMmBufferBase
+  gArmTokenSpaceGuid.PcdMmBufferSize
+
+[Depex]
+  TRUE
-- 
2.14.1