2 SMM Core Main Entry Point
4 Copyright (c) 2009 - 2012, Intel Corporation. All rights reserved.<BR>
5 This program and the accompanying materials are licensed and made available
6 under the terms and conditions of the BSD License which accompanies this
7 distribution. The full text of the license may be found at
8 http://opensource.org/licenses/bsd-license.php
10 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
11 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
15 #include "PiSmmCore.h"
18 // Physical pointer to private structure shared between SMM IPL and the SMM Core
20 SMM_CORE_PRIVATE_DATA
*gSmmCorePrivate
;
23 // SMM Core global variable for SMM System Table. Only accessed as a physical structure in SMRAM.
25 EFI_SMM_SYSTEM_TABLE2 gSmmCoreSmst
= {
28 EFI_SMM_SYSTEM_TABLE2_REVISION
,
29 sizeof (gSmmCoreSmst
.Hdr
)
31 NULL
, // SmmFirmwareVendor
32 0, // SmmFirmwareRevision
33 SmmInstallConfigurationTable
,
36 (EFI_SMM_CPU_IO2
) SmmEfiNotAvailableYetArg5
, // SmmMemRead
37 (EFI_SMM_CPU_IO2
) SmmEfiNotAvailableYetArg5
// SmmMemWrite
40 (EFI_SMM_CPU_IO2
) SmmEfiNotAvailableYetArg5
, // SmmIoRead
41 (EFI_SMM_CPU_IO2
) SmmEfiNotAvailableYetArg5
// SmmIoWrite
48 NULL
, // SmmStartupThisAp
49 0, // CurrentlyExecutingCpu
51 NULL
, // CpuSaveStateSize
53 0, // NumberOfTableEntries
54 NULL
, // SmmConfigurationTable
55 SmmInstallProtocolInterface
,
56 SmmUninstallProtocolInterface
,
58 SmmRegisterProtocolNotify
,
67 // Flag to determine if the platform has performed a legacy boot.
68 // If this flag is TRUE, then the runtime code and runtime data associated with the
69 // SMM IPL are converted to free memory, so the SMM COre must guarantee that is
70 // does not touch of the code/data associated with the SMM IPL if this flag is TRUE.
72 BOOLEAN mInLegacyBoot
= FALSE
;
75 // Table of SMI Handlers that are registered by the SMM Core when it is initialized
77 SMM_CORE_SMI_HANDLERS mSmmCoreSmiHandlers
[] = {
78 { SmmDriverDispatchHandler
, &gEfiEventDxeDispatchGuid
, NULL
, TRUE
},
79 { SmmReadyToLockHandler
, &gEfiDxeSmmReadyToLockProtocolGuid
, NULL
, TRUE
},
80 { SmmLegacyBootHandler
, &gEfiEventLegacyBootGuid
, NULL
, FALSE
},
81 { NULL
, NULL
, NULL
, FALSE
}
85 Place holder function until all the SMM System Table Service are available.
87 Note: This function is only used by SMRAM invocation. It is never used by DXE invocation.
95 @return EFI_NOT_AVAILABLE_YET
100 SmmEfiNotAvailableYetArg5 (
109 // This function should never be executed. If it does, then the architectural protocols
110 // have not been designed correctly.
112 return EFI_NOT_AVAILABLE_YET
;
116 Software SMI handler that is called when a Legacy Boot event is signalled. The SMM
117 Core uses this signal to know that a Legacy Boot has been performed and that
118 gSmmCorePrivate that is shared between the UEFI and SMM execution environments can
119 not be accessed from SMM anymore since that structure is considered free memory by
122 @param DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
123 @param Context Points to an optional handler context which was specified when the handler was registered.
124 @param CommBuffer A pointer to a collection of data in memory that will
125 be conveyed from a non-SMM environment into an SMM environment.
126 @param CommBufferSize The size of the CommBuffer.
133 SmmLegacyBootHandler (
134 IN EFI_HANDLE DispatchHandle
,
135 IN CONST VOID
*Context
, OPTIONAL
136 IN OUT VOID
*CommBuffer
, OPTIONAL
137 IN OUT UINTN
*CommBufferSize OPTIONAL
140 mInLegacyBoot
= TRUE
;
145 Software SMI handler that is called when the DxeSmmReadyToLock protocol is added
146 or if gEfiEventReadyToBootGuid is signalled. This function unregisters the
147 Software SMIs that are nor required after SMRAM is locked and installs the
148 SMM Ready To Lock Protocol so SMM Drivers are informed that SMRAM is about
149 to be locked. It also verifies the the SMM CPU I/O 2 Protocol has been installed
150 and NULLs gBS and gST because they can not longer be used after SMRAM is locked.
152 @param DispatchHandle The unique handle assigned to this handler by SmiHandlerRegister().
153 @param Context Points to an optional handler context which was specified when the handler was registered.
154 @param CommBuffer A pointer to a collection of data in memory that will
155 be conveyed from a non-SMM environment into an SMM environment.
156 @param CommBufferSize The size of the CommBuffer.
163 SmmReadyToLockHandler (
164 IN EFI_HANDLE DispatchHandle
,
165 IN CONST VOID
*Context
, OPTIONAL
166 IN OUT VOID
*CommBuffer
, OPTIONAL
167 IN OUT UINTN
*CommBufferSize OPTIONAL
172 EFI_HANDLE SmmHandle
;
176 // Unregister SMI Handlers that are no required after the SMM driver dispatch is stopped
178 for (Index
= 0; mSmmCoreSmiHandlers
[Index
].HandlerType
!= NULL
; Index
++) {
179 if (mSmmCoreSmiHandlers
[Index
].UnRegister
) {
180 SmiHandlerUnRegister (mSmmCoreSmiHandlers
[Index
].DispatchHandle
);
185 // Install SMM Ready to lock protocol
188 Status
= SmmInstallProtocolInterface (
190 &gEfiSmmReadyToLockProtocolGuid
,
191 EFI_NATIVE_INTERFACE
,
196 // Make sure SMM CPU I/O 2 Procol has been installed into the handle database
198 Status
= SmmLocateProtocol (&gEfiSmmCpuIo2ProtocolGuid
, NULL
, &Interface
);
201 // Print a message on a debug build if the SMM CPU I/O 2 Protocol is not installed
204 if (EFI_ERROR (Status
)) {
205 DEBUG ((DEBUG_ERROR
, "\nSMM: SmmCpuIo Arch Protocol not present!!\n"));
210 // Assert if the CPU I/O 2 Protocol is not installed
212 ASSERT_EFI_ERROR (Status
);
215 // Display any drivers that were not dispatched because dependency expression
216 // evaluated to false if this is a debug build
219 SmmDisplayDiscoveredNotDispatched ();
223 // Not allowed to use gST or gBS after lock
232 The main entry point to SMM Foundation.
234 Note: This function is only used by SMRAM invocation. It is never used by DXE invocation.
236 @param SmmEntryContext Processor information and functionality
237 needed by SMM Foundation.
243 IN CONST EFI_SMM_ENTRY_CONTEXT
*SmmEntryContext
247 EFI_SMM_COMMUNICATE_HEADER
*CommunicateHeader
;
248 BOOLEAN InLegacyBoot
;
250 PERF_START (NULL
, "SMM", NULL
, 0) ;
253 // Update SMST using the context
255 CopyMem (&gSmmCoreSmst
.SmmStartupThisAp
, SmmEntryContext
, sizeof (EFI_SMM_ENTRY_CONTEXT
));
258 // Call platform hook before Smm Dispatch
260 PlatformHookBeforeSmmDispatch ();
263 // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
265 InLegacyBoot
= mInLegacyBoot
;
268 // Mark the InSmm flag as TRUE, it will be used by SmmBase2 protocol
270 gSmmCorePrivate
->InSmm
= TRUE
;
273 // Check to see if this is a Synchronous SMI sent through the SMM Communication
274 // Protocol or an Asynchronous SMI
276 if (gSmmCorePrivate
->CommunicationBuffer
!= NULL
) {
278 // Synchronous SMI for SMM Core or request from Communicate protocol
280 CommunicateHeader
= (EFI_SMM_COMMUNICATE_HEADER
*)gSmmCorePrivate
->CommunicationBuffer
;
281 gSmmCorePrivate
->BufferSize
-= OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER
, Data
);
283 &CommunicateHeader
->HeaderGuid
,
285 CommunicateHeader
->Data
,
286 &gSmmCorePrivate
->BufferSize
290 // Update CommunicationBuffer, BufferSize and ReturnStatus
291 // Communicate service finished, reset the pointer to CommBuffer to NULL
293 gSmmCorePrivate
->BufferSize
+= OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER
, Data
);
294 gSmmCorePrivate
->CommunicationBuffer
= NULL
;
295 gSmmCorePrivate
->ReturnStatus
= (Status
== EFI_SUCCESS
) ? EFI_SUCCESS
: EFI_NOT_FOUND
;
300 // Process Asynchronous SMI sources
302 SmiManage (NULL
, NULL
, NULL
, NULL
);
305 // Call platform hook after Smm Dispatch
307 PlatformHookAfterSmmDispatch ();
310 // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
314 // Clear the InSmm flag as we are going to leave SMM
316 gSmmCorePrivate
->InSmm
= FALSE
;
319 PERF_END (NULL
, "SMM", NULL
, 0) ;
323 The Entry Point for SMM Core
325 Install DXE Protocols and reload SMM Core into SMRAM and register SMM Core
326 EntryPoint on the SMI vector.
328 Note: This function is called for both DXE invocation and SMRAM invocation.
330 @param ImageHandle The firmware allocated handle for the EFI image.
331 @param SystemTable A pointer to the EFI System Table.
333 @retval EFI_SUCCESS The entry point is executed successfully.
334 @retval Other Some error occurred when executing this entry point.
340 IN EFI_HANDLE ImageHandle
,
341 IN EFI_SYSTEM_TABLE
*SystemTable
348 // Get SMM Core Private context passed in from SMM IPL in ImageHandle.
350 gSmmCorePrivate
= (SMM_CORE_PRIVATE_DATA
*)ImageHandle
;
353 // Fill in SMRAM physical address for the SMM Services Table and the SMM Entry Point.
355 gSmmCorePrivate
->Smst
= &gSmmCoreSmst
;
356 gSmmCorePrivate
->SmmEntryPoint
= SmmEntryPoint
;
359 // Initialize memory service using free SMRAM
361 SmmInitializeMemoryServices (gSmmCorePrivate
->SmramRangeCount
, gSmmCorePrivate
->SmramRanges
);
364 // Register all SMI Handlers required by the SMM Core
366 for (Index
= 0; mSmmCoreSmiHandlers
[Index
].HandlerType
!= NULL
; Index
++) {
367 Status
= SmiHandlerRegister (
368 mSmmCoreSmiHandlers
[Index
].Handler
,
369 mSmmCoreSmiHandlers
[Index
].HandlerType
,
370 &mSmmCoreSmiHandlers
[Index
].DispatchHandle
372 ASSERT_EFI_ERROR (Status
);