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
;
249 PERF_START (NULL
, "SMM", NULL
, 0) ;
252 // Update SMST using the context
254 CopyMem (&gSmmCoreSmst
.SmmStartupThisAp
, SmmEntryContext
, sizeof (EFI_SMM_ENTRY_CONTEXT
));
257 // Call platform hook before Smm Dispatch
259 PlatformHookBeforeSmmDispatch ();
262 // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
264 if (!mInLegacyBoot
) {
266 // Mark the InSmm flag as TRUE, it will be used by SmmBase2 protocol
268 gSmmCorePrivate
->InSmm
= TRUE
;
271 // Check to see if this is a Synchronous SMI sent through the SMM Communication
272 // Protocol or an Asynchronous SMI
274 if (gSmmCorePrivate
->CommunicationBuffer
!= NULL
) {
276 // Synchronous SMI for SMM Core or request from Communicate protocol
278 CommunicateHeader
= (EFI_SMM_COMMUNICATE_HEADER
*)gSmmCorePrivate
->CommunicationBuffer
;
279 gSmmCorePrivate
->BufferSize
-= OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER
, Data
);
281 &CommunicateHeader
->HeaderGuid
,
283 CommunicateHeader
->Data
,
284 &gSmmCorePrivate
->BufferSize
288 // Update CommunicationBuffer, BufferSize and ReturnStatus
289 // Communicate service finished, reset the pointer to CommBuffer to NULL
291 gSmmCorePrivate
->BufferSize
+= OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER
, Data
);
292 gSmmCorePrivate
->CommunicationBuffer
= NULL
;
293 gSmmCorePrivate
->ReturnStatus
= (Status
== EFI_SUCCESS
) ? EFI_SUCCESS
: EFI_NOT_FOUND
;
298 // Process Asynchronous SMI sources
300 SmiManage (NULL
, NULL
, NULL
, NULL
);
303 // Call platform hook after Smm Dispatch
305 PlatformHookAfterSmmDispatch ();
308 // If a legacy boot has occured, then make sure gSmmCorePrivate is not accessed
310 if (!mInLegacyBoot
) {
312 // Clear the InSmm flag as we are going to leave SMM
314 gSmmCorePrivate
->InSmm
= FALSE
;
317 PERF_END (NULL
, "SMM", NULL
, 0) ;
321 The Entry Point for SMM Core
323 Install DXE Protocols and reload SMM Core into SMRAM and register SMM Core
324 EntryPoint on the SMI vector.
326 Note: This function is called for both DXE invocation and SMRAM invocation.
328 @param ImageHandle The firmware allocated handle for the EFI image.
329 @param SystemTable A pointer to the EFI System Table.
331 @retval EFI_SUCCESS The entry point is executed successfully.
332 @retval Other Some error occurred when executing this entry point.
338 IN EFI_HANDLE ImageHandle
,
339 IN EFI_SYSTEM_TABLE
*SystemTable
346 // Get SMM Core Private context passed in from SMM IPL in ImageHandle.
348 gSmmCorePrivate
= (SMM_CORE_PRIVATE_DATA
*)ImageHandle
;
351 // Fill in SMRAM physical address for the SMM Services Table and the SMM Entry Point.
353 gSmmCorePrivate
->Smst
= &gSmmCoreSmst
;
354 gSmmCorePrivate
->SmmEntryPoint
= SmmEntryPoint
;
357 // Initialize memory service using free SMRAM
359 SmmInitializeMemoryServices (gSmmCorePrivate
->SmramRangeCount
, gSmmCorePrivate
->SmramRanges
);
362 // Register all SMI Handlers required by the SMM Core
364 for (Index
= 0; mSmmCoreSmiHandlers
[Index
].HandlerType
!= NULL
; Index
++) {
365 Status
= SmiHandlerRegister (
366 mSmmCoreSmiHandlers
[Index
].Handler
,
367 mSmmCoreSmiHandlers
[Index
].HandlerType
,
368 &mSmmCoreSmiHandlers
[Index
].DispatchHandle
370 ASSERT_EFI_ERROR (Status
);