OvmfPkg: add DXE_DRIVER for providing TSEG-as-SMRAM during boot-time DXE

The SMM core depends on EFI_SMM_ACCESS2_PROTOCOL. This small driver (which
is a thin wrapper around "OvmfPkg/SmmAccess/SmramInternal.c" that was
added in the previous patch) provides that protocol.

Notably, EFI_SMM_ACCESS2_PROTOCOL is for boot time only, therefore
our MODULE_TYPE is not DXE_RUNTIME_DRIVER.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Michael Kinney <michael.d.kinney@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19041 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 156 insertions, 0 deletions

diff --git a/OvmfPkg/SmmAccess/SmmAccess2Dxe.c b/OvmfPkg/SmmAccess/SmmAccess2Dxe.c
new file mode 100644
index 0000000000..d5130399b0
--- /dev/null
+++ b/OvmfPkg/SmmAccess/SmmAccess2Dxe.c
@@ -0,0 +1,156 @@
+/** @file

+

+  A DXE_DRIVER providing SMRAM access by producing EFI_SMM_ACCESS2_PROTOCOL.

+

+  Q35 TSEG is expected to have been verified and set up by the SmmAccessPei

+  driver.

+

+  Copyright (C) 2013, 2015, Red Hat, Inc.<BR>

+  Copyright (c) 2009 - 2010, 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 <Library/DebugLib.h>

+#include <Library/PcdLib.h>

+#include <Library/UefiBootServicesTableLib.h>

+#include <Protocol/SmmAccess2.h>

+

+#include "SmramInternal.h"

+

+/**

+  Opens the SMRAM area to be accessible by a boot-service driver.

+

+  This function "opens" SMRAM so that it is visible while not inside of SMM.

+  The function should return EFI_UNSUPPORTED if the hardware does not support

+  hiding of SMRAM. The function should return EFI_DEVICE_ERROR if the SMRAM

+  configuration is locked.

+

+  @param[in] This           The EFI_SMM_ACCESS2_PROTOCOL instance.

+

+  @retval EFI_SUCCESS       The operation was successful.

+  @retval EFI_UNSUPPORTED   The system does not support opening and closing of

+                            SMRAM.

+  @retval EFI_DEVICE_ERROR  SMRAM cannot be opened, perhaps because it is

+                            locked.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+SmmAccess2DxeOpen (

+  IN EFI_SMM_ACCESS2_PROTOCOL  *This

+  )

+{

+  return SmramAccessOpen (&This->LockState, &This->OpenState);

+}

+

+/**

+  Inhibits access to the SMRAM.

+

+  This function "closes" SMRAM so that it is not visible while outside of SMM.

+  The function should return EFI_UNSUPPORTED if the hardware does not support

+  hiding of SMRAM.

+

+  @param[in] This           The EFI_SMM_ACCESS2_PROTOCOL instance.

+

+  @retval EFI_SUCCESS       The operation was successful.

+  @retval EFI_UNSUPPORTED   The system does not support opening and closing of

+                            SMRAM.

+  @retval EFI_DEVICE_ERROR  SMRAM cannot be closed.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+SmmAccess2DxeClose (

+  IN EFI_SMM_ACCESS2_PROTOCOL  *This

+  )

+{

+  return SmramAccessClose (&This->LockState, &This->OpenState);

+}

+

+/**

+  Inhibits access to the SMRAM.

+

+  This function prohibits access to the SMRAM region.  This function is usually

+  implemented such that it is a write-once operation.

+

+  @param[in] This          The EFI_SMM_ACCESS2_PROTOCOL instance.

+

+  @retval EFI_SUCCESS      The device was successfully locked.

+  @retval EFI_UNSUPPORTED  The system does not support locking of SMRAM.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+SmmAccess2DxeLock (

+  IN EFI_SMM_ACCESS2_PROTOCOL  *This

+  )

+{

+  return SmramAccessLock (&This->LockState, &This->OpenState);

+}

+

+/**

+  Queries the memory controller for the possible regions that will support

+  SMRAM.

+

+  @param[in]     This           The EFI_SMM_ACCESS2_PROTOCOL instance.

+  @param[in,out] SmramMapSize   A pointer to the size, in bytes, of the

+                                SmramMemoryMap buffer.

+  @param[in,out] SmramMap       A pointer to the buffer in which firmware

+                                places the current memory map.

+

+  @retval EFI_SUCCESS           The chipset supported the given resource.

+  @retval EFI_BUFFER_TOO_SMALL  The SmramMap parameter was too small.  The

+                                current buffer size needed to hold the memory

+                                map is returned in SmramMapSize.

+**/

+STATIC

+EFI_STATUS

+EFIAPI

+SmmAccess2DxeGetCapabilities (

+  IN CONST EFI_SMM_ACCESS2_PROTOCOL  *This,

+  IN OUT UINTN                       *SmramMapSize,

+  IN OUT EFI_SMRAM_DESCRIPTOR        *SmramMap

+  )

+{

+  return SmramAccessGetCapabilities (This->LockState, This->OpenState,

+           SmramMapSize, SmramMap);

+}

+

+//

+// LockState and OpenState will be filled in by the entry point.

+//

+STATIC EFI_SMM_ACCESS2_PROTOCOL mAccess2 = {

+  &SmmAccess2DxeOpen,

+  &SmmAccess2DxeClose,

+  &SmmAccess2DxeLock,

+  &SmmAccess2DxeGetCapabilities

+};

+

+//

+// Entry point of this driver.

+//

+EFI_STATUS

+EFIAPI

+SmmAccess2DxeEntryPoint (

+  IN EFI_HANDLE       ImageHandle,

+  IN EFI_SYSTEM_TABLE *SystemTable

+  )

+{

+  //

+  // This module should only be included if SMRAM support is required.

+  //

+  ASSERT (FeaturePcdGet (PcdSmmSmramRequire));

+

+  GetStates (&mAccess2.LockState, &mAccess2.OpenState);

+  return gBS->InstallMultipleProtocolInterfaces (&ImageHandle,

+                &gEfiSmmAccess2ProtocolGuid, &mAccess2,

+                NULL);

+}