system76-edk2/MdeModulePkg/Core/PiSmmCore/PiSmmCorePrivateData.h
Star Zeng c03beb762a MdeModulePkg PiSmmCore: Remove a hidden assumption of SMRAM reservation
that assumes the SMRAM reserved range is only at the end of the SMRAM descriptor.

          //
          // This range has reserved area, calculate the left free size
          //
          gSmmCorePrivate->SmramRanges[Index].PhysicalSize = SmramResRegion->SmramReservedStart - gSmmCorePrivate->SmramRanges[Index].CpuStart;

Imagine the following scenario where we just reserve the first page of the SMRAM range:

SMRAM Descriptor:
  Start: 0x80000000
  Size: 0x02000000

Reserved Range:
  Start: 0x80000000
  Size: 0x00001000

In this case the adjustment to the SMRAM range size yields zero: ReservedStart - SMRAM Start is 0x80000000 - 0x80000000 = 0.
So even though most of the range is still free the IPL code decides its unusable.

The problem comes from the email thread: [edk2] PiSmmIpl SMRAM Reservation Logic.
http://thread.gmane.org/gmane.comp.bios.tianocore.devel/15268

Also to follow the idea in the email thread, the patch is to
1. Keep only one copy of full SMRAM ranges in gSmmCorePrivate->SmramRanges,
split record for SmmConfiguration->SmramReservedRegions and SMM Core that
will be marked to be EFI_ALLOCATED in gSmmCorePrivate->SmramRanges.
2. Handle SmmConfiguration->SmramReservedRegions at beginning of, at end of,
in the middle of, or cross multiple SmramRanges.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18031 6f19259b-4bc3-4df7-8a09-765794883524
2015-07-26 07:38:12 +00:00

126 lines
5.6 KiB
C

/** @file
The internal header file that declared a data structure that is shared
between the SMM IPL and the SMM Core.
Copyright (c) 2009 - 2015, 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.
**/
#ifndef _PI_SMM_CORE_PRIVATE_DATA_H_
#define _PI_SMM_CORE_PRIVATE_DATA_H_
///
/// Define values for the communications buffer used when gEfiEventDxeDispatchGuid is
/// event signaled. This event is signaled by the DXE Core each time the DXE Core
/// dispatcher has completed its work. When this event is signaled, the SMM Core
/// if notified, so the SMM Core can dispatch SMM drivers. If COMM_BUFFER_SMM_DISPATCH_ERROR
/// is returned in the communication buffer, then an error occurred dispatching SMM
/// Drivers. If COMM_BUFFER_SMM_DISPATCH_SUCCESS is returned, then the SMM Core
/// dispatched all the drivers it could. If COMM_BUFFER_SMM_DISPATCH_RESTART is
/// returned, then the SMM Core just dispatched the SMM Driver that registered
/// the SMM Entry Point enabling the use of SMM Mode. In this case, the SMM Core
/// should be notified again to dispatch more SMM Drivers using SMM Mode.
///
#define COMM_BUFFER_SMM_DISPATCH_ERROR 0x00
#define COMM_BUFFER_SMM_DISPATCH_SUCCESS 0x01
#define COMM_BUFFER_SMM_DISPATCH_RESTART 0x02
///
/// Signature for the private structure shared between the SMM IPL and the SMM Core
///
#define SMM_CORE_PRIVATE_DATA_SIGNATURE SIGNATURE_32 ('s', 'm', 'm', 'c')
///
/// Private structure that is used to share information between the SMM IPL and
/// the SMM Core. This structure is allocated from memory of type EfiRuntimeServicesData.
/// Since runtime memory types are converted to available memory when a legacy boot
/// is performed, the SMM Core must not access any fields of this structure if a legacy
/// boot is performed. As a result, the SMM IPL must create an event notification
/// for the Legacy Boot event and notify the SMM Core that a legacy boot is being
/// performed. The SMM Core can then use this information to filter accesses to
/// thos structure.
///
typedef struct {
UINTN Signature;
///
/// The ImageHandle passed into the entry point of the SMM IPL. This ImageHandle
/// is used by the SMM Core to fill in the ParentImageHandle field of the Loaded
/// Image Protocol for each SMM Driver that is dispatched by the SMM Core.
///
EFI_HANDLE SmmIplImageHandle;
///
/// The number of SMRAM ranges passed from the SMM IPL to the SMM Core. The SMM
/// Core uses these ranges of SMRAM to initialize the SMM Core memory manager.
///
UINTN SmramRangeCount;
///
/// A table of SMRAM ranges passed from the SMM IPL to the SMM Core. The SMM
/// Core uses these ranges of SMRAM to initialize the SMM Core memory manager.
///
EFI_SMRAM_DESCRIPTOR *SmramRanges;
///
/// The SMM Foundation Entry Point. The SMM Core fills in this field when the
/// SMM Core is initialized. The SMM IPL is responsbile for registering this entry
/// point with the SMM Configuration Protocol. The SMM Configuration Protocol may
/// not be available at the time the SMM IPL and SMM Core are started, so the SMM IPL
/// sets up a protocol notification on the SMM Configuration Protocol and registers
/// the SMM Foundation Entry Point as soon as the SMM Configuration Protocol is
/// available.
///
EFI_SMM_ENTRY_POINT SmmEntryPoint;
///
/// Boolean flag set to TRUE while an SMI is being processed by the SMM Core.
///
BOOLEAN SmmEntryPointRegistered;
///
/// Boolean flag set to TRUE while an SMI is being processed by the SMM Core.
///
BOOLEAN InSmm;
///
/// This field is set by the SMM Core then the SMM Core is initialized. This field is
/// used by the SMM Base 2 Protocol and SMM Communication Protocol implementations in
/// the SMM IPL.
///
EFI_SMM_SYSTEM_TABLE2 *Smst;
///
/// This field is used by the SMM Communicatioon Protocol to pass a buffer into
/// a software SMI handler and for the software SMI handler to pass a buffer back to
/// the caller of the SMM Communication Protocol.
///
VOID *CommunicationBuffer;
///
/// This field is used by the SMM Communicatioon Protocol to pass the size of a buffer,
/// in bytes, into a software SMI handler and for the software SMI handler to pass the
/// size, in bytes, of a buffer back to the caller of the SMM Communication Protocol.
///
UINTN BufferSize;
///
/// This field is used by the SMM Communication Protocol to pass the return status from
/// a software SMI handler back to the caller of the SMM Communication Protocol.
///
EFI_STATUS ReturnStatus;
EFI_PHYSICAL_ADDRESS PiSmmCoreImageBase;
UINT64 PiSmmCoreImageSize;
EFI_PHYSICAL_ADDRESS PiSmmCoreEntryPoint;
} SMM_CORE_PRIVATE_DATA;
#endif