1 /** @file
2   SMM IPL that produces SMM related runtime protocols and load the SMM Core into SMRAM
3 
4   Copyright (c) 2009 - 2016, 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
9 
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.
12 
13 **/
14 
15 #include <PiDxe.h>
16 
17 #include <Protocol/SmmBase2.h>
18 #include <Protocol/SmmCommunication.h>
19 #include <Protocol/SmmAccess2.h>
20 #include <Protocol/SmmConfiguration.h>
21 #include <Protocol/SmmControl2.h>
22 #include <Protocol/DxeSmmReadyToLock.h>
23 #include <Protocol/Cpu.h>
24 
25 #include <Guid/EventGroup.h>
26 #include <Guid/EventLegacyBios.h>
27 #include <Guid/LoadModuleAtFixedAddress.h>
28 
29 #include <Library/BaseLib.h>
30 #include <Library/BaseMemoryLib.h>
31 #include <Library/PeCoffLib.h>
32 #include <Library/CacheMaintenanceLib.h>
33 #include <Library/MemoryAllocationLib.h>
34 #include <Library/DebugLib.h>
35 #include <Library/UefiBootServicesTableLib.h>
36 #include <Library/DxeServicesTableLib.h>
37 #include <Library/DxeServicesLib.h>
38 #include <Library/UefiLib.h>
39 #include <Library/UefiRuntimeLib.h>
40 #include <Library/PcdLib.h>
41 #include <Library/ReportStatusCodeLib.h>
42 
43 #include "PiSmmCorePrivateData.h"
44 
45 //
46 // Function prototypes from produced protocols
47 //
48 
49 /**
50   Indicate whether the driver is currently executing in the SMM Initialization phase.
51 
52   @param   This                    The EFI_SMM_BASE2_PROTOCOL instance.
53   @param   InSmram                 Pointer to a Boolean which, on return, indicates that the driver is currently executing
54                                    inside of SMRAM (TRUE) or outside of SMRAM (FALSE).
55 
56   @retval  EFI_INVALID_PARAMETER   InSmram was NULL.
57   @retval  EFI_SUCCESS             The call returned successfully.
58 
59 **/
60 EFI_STATUS
61 EFIAPI
62 SmmBase2InSmram (
63   IN CONST EFI_SMM_BASE2_PROTOCOL  *This,
64   OUT      BOOLEAN                 *InSmram
65   );
66 
67 /**
68   Retrieves the location of the System Management System Table (SMST).
69 
70   @param   This                    The EFI_SMM_BASE2_PROTOCOL instance.
71   @param   Smst                    On return, points to a pointer to the System Management Service Table (SMST).
72 
73   @retval  EFI_INVALID_PARAMETER   Smst or This was invalid.
74   @retval  EFI_SUCCESS             The memory was returned to the system.
75   @retval  EFI_UNSUPPORTED         Not in SMM.
76 
77 **/
78 EFI_STATUS
79 EFIAPI
80 SmmBase2GetSmstLocation (
81   IN CONST EFI_SMM_BASE2_PROTOCOL  *This,
82   OUT      EFI_SMM_SYSTEM_TABLE2   **Smst
83   );
84 
85 /**
86   Communicates with a registered handler.
87 
88   This function provides a service to send and receive messages from a registered
89   UEFI service.  This function is part of the SMM Communication Protocol that may
90   be called in physical mode prior to SetVirtualAddressMap() and in virtual mode
91   after SetVirtualAddressMap().
92 
93   @param[in]     This                The EFI_SMM_COMMUNICATION_PROTOCOL instance.
94   @param[in, out] CommBuffer          A pointer to the buffer to convey into SMRAM.
95   @param[in, out] CommSize            The size of the data buffer being passed in.On exit, the size of data
96                                      being returned. Zero if the handler does not wish to reply with any data.
97 
98   @retval EFI_SUCCESS                The message was successfully posted.
99   @retval EFI_INVALID_PARAMETER      The CommBuffer was NULL.
100 **/
101 EFI_STATUS
102 EFIAPI
103 SmmCommunicationCommunicate (
104   IN CONST EFI_SMM_COMMUNICATION_PROTOCOL  *This,
105   IN OUT VOID                              *CommBuffer,
106   IN OUT UINTN                             *CommSize
107   );
108 
109 /**
110   Event notification that is fired every time a gEfiSmmConfigurationProtocol installs.
111 
112   @param  Event                 The Event that is being processed, not used.
113   @param  Context               Event Context, not used.
114 
115 **/
116 VOID
117 EFIAPI
118 SmmIplSmmConfigurationEventNotify (
119   IN EFI_EVENT  Event,
120   IN VOID       *Context
121   );
122 
123 /**
124   Event notification that is fired every time a DxeSmmReadyToLock protocol is added
125   or if gEfiEventReadyToBootGuid is signalled.
126 
127   @param  Event                 The Event that is being processed, not used.
128   @param  Context               Event Context, not used.
129 
130 **/
131 VOID
132 EFIAPI
133 SmmIplReadyToLockEventNotify (
134   IN EFI_EVENT  Event,
135   IN VOID       *Context
136   );
137 
138 /**
139   Event notification that is fired when DxeDispatch Event Group is signaled.
140 
141   @param  Event                 The Event that is being processed, not used.
142   @param  Context               Event Context, not used.
143 
144 **/
145 VOID
146 EFIAPI
147 SmmIplDxeDispatchEventNotify (
148   IN EFI_EVENT  Event,
149   IN VOID       *Context
150   );
151 
152 /**
153   Event notification that is fired when a GUIDed Event Group is signaled.
154 
155   @param  Event                 The Event that is being processed, not used.
156   @param  Context               Event Context, not used.
157 
158 **/
159 VOID
160 EFIAPI
161 SmmIplGuidedEventNotify (
162   IN EFI_EVENT  Event,
163   IN VOID       *Context
164   );
165 
166 /**
167   Event notification that is fired when EndOfDxe Event Group is signaled.
168 
169   @param  Event                 The Event that is being processed, not used.
170   @param  Context               Event Context, not used.
171 
172 **/
173 VOID
174 EFIAPI
175 SmmIplEndOfDxeEventNotify (
176   IN EFI_EVENT  Event,
177   IN VOID       *Context
178   );
179 
180 /**
181   Notification function of EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE.
182 
183   This is a notification function registered on EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
184   It convers pointer to new virtual address.
185 
186   @param  Event        Event whose notification function is being invoked.
187   @param  Context      Pointer to the notification function's context.
188 
189 **/
190 VOID
191 EFIAPI
192 SmmIplSetVirtualAddressNotify (
193   IN EFI_EVENT  Event,
194   IN VOID       *Context
195   );
196 
197 //
198 // Data structure used to declare a table of protocol notifications and event
199 // notifications required by the SMM IPL
200 //
201 typedef struct {
202   BOOLEAN           Protocol;
203   BOOLEAN           CloseOnLock;
204   EFI_GUID          *Guid;
205   EFI_EVENT_NOTIFY  NotifyFunction;
206   VOID              *NotifyContext;
207   EFI_TPL           NotifyTpl;
208   EFI_EVENT         Event;
209 } SMM_IPL_EVENT_NOTIFICATION;
210 
211 //
212 // Handle to install the SMM Base2 Protocol and the SMM Communication Protocol
213 //
214 EFI_HANDLE  mSmmIplHandle = NULL;
215 
216 //
217 // SMM Base 2 Protocol instance
218 //
219 EFI_SMM_BASE2_PROTOCOL  mSmmBase2 = {
220   SmmBase2InSmram,
221   SmmBase2GetSmstLocation
222 };
223 
224 //
225 // SMM Communication Protocol instance
226 //
227 EFI_SMM_COMMUNICATION_PROTOCOL  mSmmCommunication = {
228   SmmCommunicationCommunicate
229 };
230 
231 //
232 // SMM Core Private Data structure that contains the data shared between
233 // the SMM IPL and the SMM Core.
234 //
235 SMM_CORE_PRIVATE_DATA  mSmmCorePrivateData = {
236   SMM_CORE_PRIVATE_DATA_SIGNATURE,    // Signature
237   NULL,                               // SmmIplImageHandle
238   0,                                  // SmramRangeCount
239   NULL,                               // SmramRanges
240   NULL,                               // SmmEntryPoint
241   FALSE,                              // SmmEntryPointRegistered
242   FALSE,                              // InSmm
243   NULL,                               // Smst
244   NULL,                               // CommunicationBuffer
245   0,                                  // BufferSize
246   EFI_SUCCESS                         // ReturnStatus
247 };
248 
249 //
250 // Global pointer used to access mSmmCorePrivateData from outside and inside SMM
251 //
252 SMM_CORE_PRIVATE_DATA  *gSmmCorePrivate = &mSmmCorePrivateData;
253 
254 //
255 // SMM IPL global variables
256 //
257 EFI_SMM_CONTROL2_PROTOCOL  *mSmmControl2;
258 EFI_SMM_ACCESS2_PROTOCOL   *mSmmAccess;
259 EFI_SMRAM_DESCRIPTOR       *mCurrentSmramRange;
260 BOOLEAN                    mSmmLocked = FALSE;
261 BOOLEAN                    mEndOfDxe  = FALSE;
262 EFI_PHYSICAL_ADDRESS       mSmramCacheBase;
263 UINT64                     mSmramCacheSize;
264 
265 EFI_SMM_COMMUNICATE_HEADER mCommunicateHeader;
266 
267 //
268 // Table of Protocol notification and GUIDed Event notifications that the SMM IPL requires
269 //
270 SMM_IPL_EVENT_NOTIFICATION  mSmmIplEvents[] = {
271   //
272   // Declare protocol notification on the SMM Configuration protocol.  When this notification is established,
273   // the associated event is immediately signalled, so the notification function will be executed and the
274   // SMM Configuration Protocol will be found if it is already in the handle database.
275   //
276   { TRUE,  FALSE, &gEfiSmmConfigurationProtocolGuid,  SmmIplSmmConfigurationEventNotify, &gEfiSmmConfigurationProtocolGuid,  TPL_NOTIFY,   NULL },
277   //
278   // Declare protocol notification on DxeSmmReadyToLock protocols.  When this notification is established,
279   // the associated event is immediately signalled, so the notification function will be executed and the
280   // DXE SMM Ready To Lock Protocol will be found if it is already in the handle database.
281   //
282   { TRUE,  TRUE,  &gEfiDxeSmmReadyToLockProtocolGuid, SmmIplReadyToLockEventNotify,      &gEfiDxeSmmReadyToLockProtocolGuid, TPL_CALLBACK, NULL },
283   //
284   // Declare event notification on EndOfDxe event.  When this notification is established,
285   // the associated event is immediately signalled, so the notification function will be executed and the
286   // SMM End Of Dxe Protocol will be found if it is already in the handle database.
287   //
288   { FALSE, TRUE,  &gEfiEndOfDxeEventGroupGuid,        SmmIplGuidedEventNotify,           &gEfiEndOfDxeEventGroupGuid,        TPL_CALLBACK, NULL },
289   //
290   // Declare event notification on EndOfDxe event.  This is used to set EndOfDxe event signaled flag.
291   //
292   { FALSE, TRUE,  &gEfiEndOfDxeEventGroupGuid,        SmmIplEndOfDxeEventNotify,         &gEfiEndOfDxeEventGroupGuid,        TPL_CALLBACK, NULL },
293   //
294   // Declare event notification on the DXE Dispatch Event Group.  This event is signaled by the DXE Core
295   // each time the DXE Core dispatcher has completed its work.  When this event is signalled, the SMM Core
296   // if notified, so the SMM Core can dispatch SMM drivers.
297   //
298   { FALSE, TRUE,  &gEfiEventDxeDispatchGuid,          SmmIplDxeDispatchEventNotify,      &gEfiEventDxeDispatchGuid,          TPL_CALLBACK, NULL },
299   //
300   // Declare event notification on Ready To Boot Event Group.  This is an extra event notification that is
301   // used to make sure SMRAM is locked before any boot options are processed.
302   //
303   { FALSE, TRUE,  &gEfiEventReadyToBootGuid,          SmmIplReadyToLockEventNotify,      &gEfiEventReadyToBootGuid,          TPL_CALLBACK, NULL },
304   //
305   // Declare event notification on Legacy Boot Event Group.  This is used to inform the SMM Core that the platform
306   // is performing a legacy boot operation, and that the UEFI environment is no longer available and the SMM Core
307   // must guarantee that it does not access any UEFI related structures outside of SMRAM.
308   // It is also to inform the SMM Core to notify SMM driver that system enter legacy boot.
309   //
310   { FALSE, FALSE, &gEfiEventLegacyBootGuid,           SmmIplGuidedEventNotify,           &gEfiEventLegacyBootGuid,           TPL_CALLBACK, NULL },
311   //
312   // Declare event notification on Exit Boot Services Event Group.  This is used to inform the SMM Core
313   // to notify SMM driver that system enter exit boot services.
314   //
315   { FALSE, FALSE, &gEfiEventExitBootServicesGuid,     SmmIplGuidedEventNotify,           &gEfiEventExitBootServicesGuid,     TPL_CALLBACK, NULL },
316   //
317   // Declare event notification on Ready To Boot Event Group.  This is used to inform the SMM Core
318   // to notify SMM driver that system enter ready to boot.
319   //
320   { FALSE, FALSE, &gEfiEventReadyToBootGuid,          SmmIplGuidedEventNotify,           &gEfiEventReadyToBootGuid,          TPL_CALLBACK, NULL },
321   //
322   // Declare event notification on SetVirtualAddressMap() Event Group.  This is used to convert gSmmCorePrivate
323   // and mSmmControl2 from physical addresses to virtual addresses.
324   //
325   { FALSE, FALSE, &gEfiEventVirtualAddressChangeGuid, SmmIplSetVirtualAddressNotify,     NULL,                               TPL_CALLBACK, NULL },
326   //
327   // Terminate the table of event notifications
328   //
329   { FALSE, FALSE, NULL,                               NULL,                              NULL,                               TPL_CALLBACK, NULL }
330 };
331 
332 /**
333   Find the maximum SMRAM cache range that covers the range specified by SmramRange.
334 
335   This function searches and joins all adjacent ranges of SmramRange into a range to be cached.
336 
337   @param   SmramRange       The SMRAM range to search from.
338   @param   SmramCacheBase   The returned cache range base.
339   @param   SmramCacheSize   The returned cache range size.
340 
341 **/
342 VOID
GetSmramCacheRange(IN EFI_SMRAM_DESCRIPTOR * SmramRange,OUT EFI_PHYSICAL_ADDRESS * SmramCacheBase,OUT UINT64 * SmramCacheSize)343 GetSmramCacheRange (
344   IN  EFI_SMRAM_DESCRIPTOR *SmramRange,
345   OUT EFI_PHYSICAL_ADDRESS *SmramCacheBase,
346   OUT UINT64               *SmramCacheSize
347   )
348 {
349   UINTN                Index;
350   EFI_PHYSICAL_ADDRESS RangeCpuStart;
351   UINT64               RangePhysicalSize;
352   BOOLEAN              FoundAjacentRange;
353 
354   *SmramCacheBase = SmramRange->CpuStart;
355   *SmramCacheSize = SmramRange->PhysicalSize;
356 
357   do {
358     FoundAjacentRange = FALSE;
359     for (Index = 0; Index < gSmmCorePrivate->SmramRangeCount; Index++) {
360       RangeCpuStart     = gSmmCorePrivate->SmramRanges[Index].CpuStart;
361       RangePhysicalSize = gSmmCorePrivate->SmramRanges[Index].PhysicalSize;
362       if (RangeCpuStart < *SmramCacheBase && *SmramCacheBase == (RangeCpuStart + RangePhysicalSize)) {
363         *SmramCacheBase   = RangeCpuStart;
364         *SmramCacheSize  += RangePhysicalSize;
365         FoundAjacentRange = TRUE;
366       } else if ((*SmramCacheBase + *SmramCacheSize) == RangeCpuStart && RangePhysicalSize > 0) {
367         *SmramCacheSize  += RangePhysicalSize;
368         FoundAjacentRange = TRUE;
369       }
370     }
371   } while (FoundAjacentRange);
372 
373 }
374 
375 /**
376   Indicate whether the driver is currently executing in the SMM Initialization phase.
377 
378   @param   This                    The EFI_SMM_BASE2_PROTOCOL instance.
379   @param   InSmram                 Pointer to a Boolean which, on return, indicates that the driver is currently executing
380                                    inside of SMRAM (TRUE) or outside of SMRAM (FALSE).
381 
382   @retval  EFI_INVALID_PARAMETER   InSmram was NULL.
383   @retval  EFI_SUCCESS             The call returned successfully.
384 
385 **/
386 EFI_STATUS
387 EFIAPI
SmmBase2InSmram(IN CONST EFI_SMM_BASE2_PROTOCOL * This,OUT BOOLEAN * InSmram)388 SmmBase2InSmram (
389   IN CONST EFI_SMM_BASE2_PROTOCOL  *This,
390   OUT      BOOLEAN                 *InSmram
391   )
392 {
393   if (InSmram == NULL) {
394     return EFI_INVALID_PARAMETER;
395   }
396 
397   *InSmram = gSmmCorePrivate->InSmm;
398 
399   return EFI_SUCCESS;
400 }
401 
402 /**
403   Retrieves the location of the System Management System Table (SMST).
404 
405   @param   This                    The EFI_SMM_BASE2_PROTOCOL instance.
406   @param   Smst                    On return, points to a pointer to the System Management Service Table (SMST).
407 
408   @retval  EFI_INVALID_PARAMETER   Smst or This was invalid.
409   @retval  EFI_SUCCESS             The memory was returned to the system.
410   @retval  EFI_UNSUPPORTED         Not in SMM.
411 
412 **/
413 EFI_STATUS
414 EFIAPI
SmmBase2GetSmstLocation(IN CONST EFI_SMM_BASE2_PROTOCOL * This,OUT EFI_SMM_SYSTEM_TABLE2 ** Smst)415 SmmBase2GetSmstLocation (
416   IN CONST EFI_SMM_BASE2_PROTOCOL  *This,
417   OUT      EFI_SMM_SYSTEM_TABLE2   **Smst
418   )
419 {
420   if ((This == NULL) ||(Smst == NULL)) {
421     return EFI_INVALID_PARAMETER;
422   }
423 
424   if (!gSmmCorePrivate->InSmm) {
425     return EFI_UNSUPPORTED;
426   }
427 
428   *Smst = gSmmCorePrivate->Smst;
429 
430   return EFI_SUCCESS;
431 }
432 
433 /**
434   Communicates with a registered handler.
435 
436   This function provides a service to send and receive messages from a registered
437   UEFI service.  This function is part of the SMM Communication Protocol that may
438   be called in physical mode prior to SetVirtualAddressMap() and in virtual mode
439   after SetVirtualAddressMap().
440 
441   @param[in] This                The EFI_SMM_COMMUNICATION_PROTOCOL instance.
442   @param[in, out] CommBuffer          A pointer to the buffer to convey into SMRAM.
443   @param[in, out] CommSize            The size of the data buffer being passed in.On exit, the size of data
444                                  being returned. Zero if the handler does not wish to reply with any data.
445 
446   @retval EFI_SUCCESS            The message was successfully posted.
447   @retval EFI_INVALID_PARAMETER  The CommBuffer was NULL.
448 **/
449 EFI_STATUS
450 EFIAPI
SmmCommunicationCommunicate(IN CONST EFI_SMM_COMMUNICATION_PROTOCOL * This,IN OUT VOID * CommBuffer,IN OUT UINTN * CommSize)451 SmmCommunicationCommunicate (
452   IN CONST EFI_SMM_COMMUNICATION_PROTOCOL  *This,
453   IN OUT VOID                              *CommBuffer,
454   IN OUT UINTN                             *CommSize
455   )
456 {
457   EFI_STATUS                  Status;
458   EFI_SMM_COMMUNICATE_HEADER  *CommunicateHeader;
459   BOOLEAN                     OldInSmm;
460 
461   //
462   // Check parameters
463   //
464   if ((CommBuffer == NULL) || (CommSize == NULL)) {
465     return EFI_INVALID_PARAMETER;
466   }
467 
468   //
469   // CommSize must hold HeaderGuid and MessageLength
470   //
471   if (*CommSize < OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER, Data)) {
472     return EFI_INVALID_PARAMETER;
473   }
474 
475   //
476   // If not already in SMM, then generate a Software SMI
477   //
478   if (!gSmmCorePrivate->InSmm && gSmmCorePrivate->SmmEntryPointRegistered) {
479     //
480     // Put arguments for Software SMI in gSmmCorePrivate
481     //
482     gSmmCorePrivate->CommunicationBuffer = CommBuffer;
483     gSmmCorePrivate->BufferSize          = *CommSize;
484 
485     //
486     // Generate Software SMI
487     //
488     Status = mSmmControl2->Trigger (mSmmControl2, NULL, NULL, FALSE, 0);
489     if (EFI_ERROR (Status)) {
490       return EFI_UNSUPPORTED;
491     }
492 
493     //
494     // Return status from software SMI
495     //
496     *CommSize = gSmmCorePrivate->BufferSize;
497     return gSmmCorePrivate->ReturnStatus;
498   }
499 
500   //
501   // If we are in SMM, then the execution mode must be physical, which means that
502   // OS established virtual addresses can not be used.  If SetVirtualAddressMap()
503   // has been called, then a direct invocation of the Software SMI is not
504   // not allowed so return EFI_INVALID_PARAMETER.
505   //
506   if (EfiGoneVirtual()) {
507     return EFI_INVALID_PARAMETER;
508   }
509 
510   //
511   // If we are not in SMM, don't allow call SmiManage() directly when SMRAM is closed or locked.
512   //
513   if ((!gSmmCorePrivate->InSmm) && (!mSmmAccess->OpenState || mSmmAccess->LockState)) {
514     return EFI_INVALID_PARAMETER;
515   }
516 
517   //
518   // Save current InSmm state and set InSmm state to TRUE
519   //
520   OldInSmm = gSmmCorePrivate->InSmm;
521   gSmmCorePrivate->InSmm = TRUE;
522 
523   //
524   // Already in SMM and before SetVirtualAddressMap(), so call SmiManage() directly.
525   //
526   CommunicateHeader = (EFI_SMM_COMMUNICATE_HEADER *)CommBuffer;
527   *CommSize -= OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER, Data);
528   Status = gSmmCorePrivate->Smst->SmiManage (
529                                     &CommunicateHeader->HeaderGuid,
530                                     NULL,
531                                     CommunicateHeader->Data,
532                                     CommSize
533                                     );
534 
535   //
536   // Update CommunicationBuffer, BufferSize and ReturnStatus
537   // Communicate service finished, reset the pointer to CommBuffer to NULL
538   //
539   *CommSize += OFFSET_OF (EFI_SMM_COMMUNICATE_HEADER, Data);
540 
541   //
542   // Restore original InSmm state
543   //
544   gSmmCorePrivate->InSmm = OldInSmm;
545 
546   return (Status == EFI_SUCCESS) ? EFI_SUCCESS : EFI_NOT_FOUND;
547 }
548 
549 /**
550   Event notification that is fired when GUIDed Event Group is signaled.
551 
552   @param  Event                 The Event that is being processed, not used.
553   @param  Context               Event Context, not used.
554 
555 **/
556 VOID
557 EFIAPI
SmmIplGuidedEventNotify(IN EFI_EVENT Event,IN VOID * Context)558 SmmIplGuidedEventNotify (
559   IN EFI_EVENT  Event,
560   IN VOID       *Context
561   )
562 {
563   UINTN                       Size;
564 
565   //
566   // Use Guid to initialize EFI_SMM_COMMUNICATE_HEADER structure
567   //
568   CopyGuid (&mCommunicateHeader.HeaderGuid, (EFI_GUID *)Context);
569   mCommunicateHeader.MessageLength = 1;
570   mCommunicateHeader.Data[0] = 0;
571 
572   //
573   // Generate the Software SMI and return the result
574   //
575   Size = sizeof (mCommunicateHeader);
576   SmmCommunicationCommunicate (&mSmmCommunication, &mCommunicateHeader, &Size);
577 }
578 
579 /**
580   Event notification that is fired when EndOfDxe Event Group is signaled.
581 
582   @param  Event                 The Event that is being processed, not used.
583   @param  Context               Event Context, not used.
584 
585 **/
586 VOID
587 EFIAPI
SmmIplEndOfDxeEventNotify(IN EFI_EVENT Event,IN VOID * Context)588 SmmIplEndOfDxeEventNotify (
589   IN EFI_EVENT  Event,
590   IN VOID       *Context
591   )
592 {
593   mEndOfDxe = TRUE;
594 }
595 
596 /**
597   Event notification that is fired when DxeDispatch Event Group is signaled.
598 
599   @param  Event                 The Event that is being processed, not used.
600   @param  Context               Event Context, not used.
601 
602 **/
603 VOID
604 EFIAPI
SmmIplDxeDispatchEventNotify(IN EFI_EVENT Event,IN VOID * Context)605 SmmIplDxeDispatchEventNotify (
606   IN EFI_EVENT  Event,
607   IN VOID       *Context
608   )
609 {
610   UINTN                       Size;
611   EFI_STATUS                  Status;
612 
613   //
614   // Keep calling the SMM Core Dispatcher until there is no request to restart it.
615   //
616   while (TRUE) {
617     //
618     // Use Guid to initialize EFI_SMM_COMMUNICATE_HEADER structure
619     // Clear the buffer passed into the Software SMI.  This buffer will return
620     // the status of the SMM Core Dispatcher.
621     //
622     CopyGuid (&mCommunicateHeader.HeaderGuid, (EFI_GUID *)Context);
623     mCommunicateHeader.MessageLength = 1;
624     mCommunicateHeader.Data[0] = 0;
625 
626     //
627     // Generate the Software SMI and return the result
628     //
629     Size = sizeof (mCommunicateHeader);
630     SmmCommunicationCommunicate (&mSmmCommunication, &mCommunicateHeader, &Size);
631 
632     //
633     // Return if there is no request to restart the SMM Core Dispatcher
634     //
635     if (mCommunicateHeader.Data[0] != COMM_BUFFER_SMM_DISPATCH_RESTART) {
636       return;
637     }
638 
639     //
640     // Attempt to reset SMRAM cacheability to UC
641     // Assume CPU AP is available at this time
642     //
643     Status = gDS->SetMemorySpaceAttributes(
644                     mSmramCacheBase,
645                     mSmramCacheSize,
646                     EFI_MEMORY_UC
647                     );
648     if (EFI_ERROR (Status)) {
649       DEBUG ((DEBUG_WARN, "SMM IPL failed to reset SMRAM window to EFI_MEMORY_UC\n"));
650     }
651 
652     //
653     // Close all SMRAM ranges to protect SMRAM
654     //
655     Status = mSmmAccess->Close (mSmmAccess);
656     ASSERT_EFI_ERROR (Status);
657 
658     //
659     // Print debug message that the SMRAM window is now closed.
660     //
661     DEBUG ((DEBUG_INFO, "SMM IPL closed SMRAM window\n"));
662   }
663 }
664 
665 /**
666   Event notification that is fired every time a gEfiSmmConfigurationProtocol installs.
667 
668   @param  Event                 The Event that is being processed, not used.
669   @param  Context               Event Context, not used.
670 
671 **/
672 VOID
673 EFIAPI
SmmIplSmmConfigurationEventNotify(IN EFI_EVENT Event,IN VOID * Context)674 SmmIplSmmConfigurationEventNotify (
675   IN EFI_EVENT  Event,
676   IN VOID       *Context
677   )
678 {
679   EFI_STATUS                      Status;
680   EFI_SMM_CONFIGURATION_PROTOCOL  *SmmConfiguration;
681 
682   //
683   // Make sure this notification is for this handler
684   //
685   Status = gBS->LocateProtocol (Context, NULL, (VOID **)&SmmConfiguration);
686   if (EFI_ERROR (Status)) {
687     return;
688   }
689 
690   //
691   // Register the SMM Entry Point provided by the SMM Core with the SMM COnfiguration protocol
692   //
693   Status = SmmConfiguration->RegisterSmmEntry (SmmConfiguration, gSmmCorePrivate->SmmEntryPoint);
694   ASSERT_EFI_ERROR (Status);
695 
696   //
697   // Set flag to indicate that the SMM Entry Point has been registered which
698   // means that SMIs are now fully operational.
699   //
700   gSmmCorePrivate->SmmEntryPointRegistered = TRUE;
701 
702   //
703   // Print debug message showing SMM Core entry point address.
704   //
705   DEBUG ((DEBUG_INFO, "SMM IPL registered SMM Entry Point address %p\n", (VOID *)(UINTN)gSmmCorePrivate->SmmEntryPoint));
706 }
707 
708 /**
709   Event notification that is fired every time a DxeSmmReadyToLock protocol is added
710   or if gEfiEventReadyToBootGuid is signaled.
711 
712   @param  Event                 The Event that is being processed, not used.
713   @param  Context               Event Context, not used.
714 
715 **/
716 VOID
717 EFIAPI
SmmIplReadyToLockEventNotify(IN EFI_EVENT Event,IN VOID * Context)718 SmmIplReadyToLockEventNotify (
719   IN EFI_EVENT  Event,
720   IN VOID       *Context
721   )
722 {
723   EFI_STATUS  Status;
724   VOID        *Interface;
725   UINTN       Index;
726 
727   //
728   // See if we are already locked
729   //
730   if (mSmmLocked) {
731     return;
732   }
733 
734   //
735   // Make sure this notification is for this handler
736   //
737   if (CompareGuid ((EFI_GUID *)Context, &gEfiDxeSmmReadyToLockProtocolGuid)) {
738     Status = gBS->LocateProtocol (&gEfiDxeSmmReadyToLockProtocolGuid, NULL, &Interface);
739     if (EFI_ERROR (Status)) {
740       return;
741     }
742   } else {
743     //
744     // If SMM is not locked yet and we got here from gEfiEventReadyToBootGuid being
745     // signaled, then gEfiDxeSmmReadyToLockProtocolGuid was not installed as expected.
746     // Print a warning on debug builds.
747     //
748     DEBUG ((DEBUG_WARN, "SMM IPL!  DXE SMM Ready To Lock Protocol not installed before Ready To Boot signal\n"));
749   }
750 
751   if (!mEndOfDxe) {
752     DEBUG ((DEBUG_ERROR, "EndOfDxe Event must be signaled before DxeSmmReadyToLock Protocol installation!\n"));
753     REPORT_STATUS_CODE (
754       EFI_ERROR_CODE | EFI_ERROR_UNRECOVERED,
755       (EFI_SOFTWARE_SMM_DRIVER | EFI_SW_EC_ILLEGAL_SOFTWARE_STATE)
756       );
757     ASSERT (FALSE);
758   }
759 
760   //
761   // Lock the SMRAM (Note: Locking SMRAM may not be supported on all platforms)
762   //
763   mSmmAccess->Lock (mSmmAccess);
764 
765   //
766   // Close protocol and event notification events that do not apply after the
767   // DXE SMM Ready To Lock Protocol has been installed or the Ready To Boot
768   // event has been signalled.
769   //
770   for (Index = 0; mSmmIplEvents[Index].NotifyFunction != NULL; Index++) {
771     if (mSmmIplEvents[Index].CloseOnLock) {
772       gBS->CloseEvent (mSmmIplEvents[Index].Event);
773     }
774   }
775 
776   //
777   // Inform SMM Core that the DxeSmmReadyToLock protocol was installed
778   //
779   SmmIplGuidedEventNotify (Event, (VOID *)&gEfiDxeSmmReadyToLockProtocolGuid);
780 
781   //
782   // Print debug message that the SMRAM window is now locked.
783   //
784   DEBUG ((DEBUG_INFO, "SMM IPL locked SMRAM window\n"));
785 
786   //
787   // Set flag so this operation will not be performed again
788   //
789   mSmmLocked = TRUE;
790 }
791 
792 /**
793   Notification function of EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE.
794 
795   This is a notification function registered on EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
796   It convers pointer to new virtual address.
797 
798   @param  Event        Event whose notification function is being invoked.
799   @param  Context      Pointer to the notification function's context.
800 
801 **/
802 VOID
803 EFIAPI
SmmIplSetVirtualAddressNotify(IN EFI_EVENT Event,IN VOID * Context)804 SmmIplSetVirtualAddressNotify (
805   IN EFI_EVENT  Event,
806   IN VOID       *Context
807   )
808 {
809   EfiConvertPointer (0x0, (VOID **)&mSmmControl2);
810 }
811 
812 /**
813   Get the fixed loading address from image header assigned by build tool. This function only be called
814   when Loading module at Fixed address feature enabled.
815 
816   @param  ImageContext              Pointer to the image context structure that describes the PE/COFF
817                                     image that needs to be examined by this function.
818   @retval EFI_SUCCESS               An fixed loading address is assigned to this image by build tools .
819   @retval EFI_NOT_FOUND             The image has no assigned fixed loading address.
820 **/
821 EFI_STATUS
GetPeCoffImageFixLoadingAssignedAddress(IN OUT PE_COFF_LOADER_IMAGE_CONTEXT * ImageContext)822 GetPeCoffImageFixLoadingAssignedAddress(
823   IN OUT PE_COFF_LOADER_IMAGE_CONTEXT  *ImageContext
824   )
825 {
826    UINTN                              SectionHeaderOffset;
827    EFI_STATUS                         Status;
828    EFI_IMAGE_SECTION_HEADER           SectionHeader;
829    EFI_IMAGE_OPTIONAL_HEADER_UNION    *ImgHdr;
830    EFI_PHYSICAL_ADDRESS               FixLoadingAddress;
831    UINT16                             Index;
832    UINTN                              Size;
833    UINT16                             NumberOfSections;
834    EFI_PHYSICAL_ADDRESS               SmramBase;
835    UINT64                             SmmCodeSize;
836    UINT64                             ValueInSectionHeader;
837    //
838    // Build tool will calculate the smm code size and then patch the PcdLoadFixAddressSmmCodePageNumber
839    //
840    SmmCodeSize = EFI_PAGES_TO_SIZE (PcdGet32(PcdLoadFixAddressSmmCodePageNumber));
841 
842    FixLoadingAddress = 0;
843    Status = EFI_NOT_FOUND;
844    SmramBase = mCurrentSmramRange->CpuStart;
845    //
846    // Get PeHeader pointer
847    //
848    ImgHdr = (EFI_IMAGE_OPTIONAL_HEADER_UNION *)((CHAR8* )ImageContext->Handle + ImageContext->PeCoffHeaderOffset);
849    SectionHeaderOffset = (UINTN)(
850                                  ImageContext->PeCoffHeaderOffset +
851                                  sizeof (UINT32) +
852                                  sizeof (EFI_IMAGE_FILE_HEADER) +
853                                  ImgHdr->Pe32.FileHeader.SizeOfOptionalHeader
854                                  );
855    NumberOfSections = ImgHdr->Pe32.FileHeader.NumberOfSections;
856 
857    //
858    // Get base address from the first section header that doesn't point to code section.
859    //
860    for (Index = 0; Index < NumberOfSections; Index++) {
861      //
862      // Read section header from file
863      //
864      Size = sizeof (EFI_IMAGE_SECTION_HEADER);
865      Status = ImageContext->ImageRead (
866                               ImageContext->Handle,
867                               SectionHeaderOffset,
868                               &Size,
869                               &SectionHeader
870                               );
871      if (EFI_ERROR (Status)) {
872        return Status;
873      }
874 
875      Status = EFI_NOT_FOUND;
876 
877      if ((SectionHeader.Characteristics & EFI_IMAGE_SCN_CNT_CODE) == 0) {
878        //
879        // Build tool saves the offset to SMRAM base as image base in PointerToRelocations & PointerToLineNumbers fields in the
880        // first section header that doesn't point to code section in image header. And there is an assumption that when the
881        // feature is enabled, if a module is assigned a loading address by tools, PointerToRelocations & PointerToLineNumbers
882        // fields should NOT be Zero, or else, these 2 fields should be set to Zero
883        //
884        ValueInSectionHeader = ReadUnaligned64((UINT64*)&SectionHeader.PointerToRelocations);
885        if (ValueInSectionHeader != 0) {
886          //
887          // Found first section header that doesn't point to code section in which build tool saves the
888          // offset to SMRAM base as image base in PointerToRelocations & PointerToLineNumbers fields
889          //
890          FixLoadingAddress = (EFI_PHYSICAL_ADDRESS)(SmramBase + (INT64)ValueInSectionHeader);
891 
892          if (SmramBase + SmmCodeSize > FixLoadingAddress && SmramBase <=  FixLoadingAddress) {
893            //
894            // The assigned address is valid. Return the specified loading address
895            //
896            ImageContext->ImageAddress = FixLoadingAddress;
897            Status = EFI_SUCCESS;
898          }
899        }
900        break;
901      }
902      SectionHeaderOffset += sizeof (EFI_IMAGE_SECTION_HEADER);
903    }
904    DEBUG ((EFI_D_INFO|EFI_D_LOAD, "LOADING MODULE FIXED INFO: Loading module at fixed address %x, Status = %r \n", FixLoadingAddress, Status));
905    return Status;
906 }
907 /**
908   Load the SMM Core image into SMRAM and executes the SMM Core from SMRAM.
909 
910   @param[in, out] SmramRange            Descriptor for the range of SMRAM to reload the
911                                         currently executing image, the rang of SMRAM to
912                                         hold SMM Core will be excluded.
913   @param[in, out] SmramRangeSmmCore     Descriptor for the range of SMRAM to hold SMM Core.
914 
915   @param[in]      Context               Context to pass into SMM Core
916 
917   @return  EFI_STATUS
918 
919 **/
920 EFI_STATUS
ExecuteSmmCoreFromSmram(IN OUT EFI_SMRAM_DESCRIPTOR * SmramRange,IN OUT EFI_SMRAM_DESCRIPTOR * SmramRangeSmmCore,IN VOID * Context)921 ExecuteSmmCoreFromSmram (
922   IN OUT EFI_SMRAM_DESCRIPTOR   *SmramRange,
923   IN OUT EFI_SMRAM_DESCRIPTOR   *SmramRangeSmmCore,
924   IN     VOID                   *Context
925   )
926 {
927   EFI_STATUS                    Status;
928   VOID                          *SourceBuffer;
929   UINTN                         SourceSize;
930   PE_COFF_LOADER_IMAGE_CONTEXT  ImageContext;
931   UINTN                         PageCount;
932   EFI_IMAGE_ENTRY_POINT         EntryPoint;
933 
934   //
935   // Search all Firmware Volumes for a PE/COFF image in a file of type SMM_CORE
936   //
937   Status = GetSectionFromAnyFvByFileType (
938              EFI_FV_FILETYPE_SMM_CORE,
939              0,
940              EFI_SECTION_PE32,
941              0,
942              &SourceBuffer,
943              &SourceSize
944              );
945   if (EFI_ERROR (Status)) {
946     return Status;
947   }
948 
949   //
950   // Initilize ImageContext
951   //
952   ImageContext.Handle    = SourceBuffer;
953   ImageContext.ImageRead = PeCoffLoaderImageReadFromMemory;
954 
955   //
956   // Get information about the image being loaded
957   //
958   Status = PeCoffLoaderGetImageInfo (&ImageContext);
959   if (EFI_ERROR (Status)) {
960     return Status;
961   }
962   //
963   // if Loading module at Fixed Address feature is enabled, the SMM core driver will be loaded to
964   // the address assigned by build tool.
965   //
966   if (PcdGet64(PcdLoadModuleAtFixAddressEnable) != 0) {
967     //
968     // Get the fixed loading address assigned by Build tool
969     //
970     Status = GetPeCoffImageFixLoadingAssignedAddress (&ImageContext);
971     if (!EFI_ERROR (Status)) {
972       //
973       // Since the memory range to load SMM CORE will be cut out in SMM core, so no need to allocate and free this range
974       //
975       PageCount = 0;
976       //
977       // Reserved Smram Region for SmmCore is not used, and remove it from SmramRangeCount.
978       //
979       gSmmCorePrivate->SmramRangeCount --;
980     } else {
981       DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED ERROR: Loading module at fixed address at address failed\n"));
982       //
983       // Allocate memory for the image being loaded from the EFI_SRAM_DESCRIPTOR
984       // specified by SmramRange
985       //
986       PageCount = (UINTN)EFI_SIZE_TO_PAGES((UINTN)ImageContext.ImageSize + ImageContext.SectionAlignment);
987 
988       ASSERT ((SmramRange->PhysicalSize & EFI_PAGE_MASK) == 0);
989       ASSERT (SmramRange->PhysicalSize > EFI_PAGES_TO_SIZE (PageCount));
990 
991       SmramRange->PhysicalSize -= EFI_PAGES_TO_SIZE (PageCount);
992       SmramRangeSmmCore->CpuStart = SmramRange->CpuStart + SmramRange->PhysicalSize;
993       SmramRangeSmmCore->PhysicalStart = SmramRange->PhysicalStart + SmramRange->PhysicalSize;
994       SmramRangeSmmCore->RegionState = SmramRange->RegionState | EFI_ALLOCATED;
995       SmramRangeSmmCore->PhysicalSize = EFI_PAGES_TO_SIZE (PageCount);
996 
997       //
998       // Align buffer on section boundary
999       //
1000       ImageContext.ImageAddress = SmramRangeSmmCore->CpuStart;
1001     }
1002   } else {
1003     //
1004     // Allocate memory for the image being loaded from the EFI_SRAM_DESCRIPTOR
1005     // specified by SmramRange
1006     //
1007     PageCount = (UINTN)EFI_SIZE_TO_PAGES((UINTN)ImageContext.ImageSize + ImageContext.SectionAlignment);
1008 
1009     ASSERT ((SmramRange->PhysicalSize & EFI_PAGE_MASK) == 0);
1010     ASSERT (SmramRange->PhysicalSize > EFI_PAGES_TO_SIZE (PageCount));
1011 
1012     SmramRange->PhysicalSize -= EFI_PAGES_TO_SIZE (PageCount);
1013     SmramRangeSmmCore->CpuStart = SmramRange->CpuStart + SmramRange->PhysicalSize;
1014     SmramRangeSmmCore->PhysicalStart = SmramRange->PhysicalStart + SmramRange->PhysicalSize;
1015     SmramRangeSmmCore->RegionState = SmramRange->RegionState | EFI_ALLOCATED;
1016     SmramRangeSmmCore->PhysicalSize = EFI_PAGES_TO_SIZE (PageCount);
1017 
1018     //
1019     // Align buffer on section boundary
1020     //
1021     ImageContext.ImageAddress = SmramRangeSmmCore->CpuStart;
1022   }
1023 
1024   ImageContext.ImageAddress += ImageContext.SectionAlignment - 1;
1025   ImageContext.ImageAddress &= ~((EFI_PHYSICAL_ADDRESS)(ImageContext.SectionAlignment - 1));
1026 
1027   //
1028   // Print debug message showing SMM Core load address.
1029   //
1030   DEBUG ((DEBUG_INFO, "SMM IPL loading SMM Core at SMRAM address %p\n", (VOID *)(UINTN)ImageContext.ImageAddress));
1031 
1032   //
1033   // Load the image to our new buffer
1034   //
1035   Status = PeCoffLoaderLoadImage (&ImageContext);
1036   if (!EFI_ERROR (Status)) {
1037     //
1038     // Relocate the image in our new buffer
1039     //
1040     Status = PeCoffLoaderRelocateImage (&ImageContext);
1041     if (!EFI_ERROR (Status)) {
1042       //
1043       // Flush the instruction cache so the image data are written before we execute it
1044       //
1045       InvalidateInstructionCacheRange ((VOID *)(UINTN)ImageContext.ImageAddress, (UINTN)ImageContext.ImageSize);
1046 
1047       //
1048       // Print debug message showing SMM Core entry point address.
1049       //
1050       DEBUG ((DEBUG_INFO, "SMM IPL calling SMM Core at SMRAM address %p\n", (VOID *)(UINTN)ImageContext.EntryPoint));
1051 
1052       gSmmCorePrivate->PiSmmCoreImageBase = ImageContext.ImageAddress;
1053       gSmmCorePrivate->PiSmmCoreImageSize = ImageContext.ImageSize;
1054       DEBUG ((DEBUG_INFO, "PiSmmCoreImageBase - 0x%016lx\n", gSmmCorePrivate->PiSmmCoreImageBase));
1055       DEBUG ((DEBUG_INFO, "PiSmmCoreImageSize - 0x%016lx\n", gSmmCorePrivate->PiSmmCoreImageSize));
1056 
1057       gSmmCorePrivate->PiSmmCoreEntryPoint = ImageContext.EntryPoint;
1058 
1059       //
1060       // Execute image
1061       //
1062       EntryPoint = (EFI_IMAGE_ENTRY_POINT)(UINTN)ImageContext.EntryPoint;
1063       Status = EntryPoint ((EFI_HANDLE)Context, gST);
1064     }
1065   }
1066 
1067   //
1068   // Always free memory allocted by GetFileBufferByFilePath ()
1069   //
1070   FreePool (SourceBuffer);
1071 
1072   return Status;
1073 }
1074 
1075 /**
1076   SMM split SMRAM entry.
1077 
1078   @param[in, out] RangeToCompare             Pointer to EFI_SMRAM_DESCRIPTOR to compare.
1079   @param[in, out] ReservedRangeToCompare     Pointer to EFI_SMM_RESERVED_SMRAM_REGION to compare.
1080   @param[out]     Ranges                     Output pointer to hold split EFI_SMRAM_DESCRIPTOR entry.
1081   @param[in, out] RangeCount                 Pointer to range count.
1082   @param[out]     ReservedRanges             Output pointer to hold split EFI_SMM_RESERVED_SMRAM_REGION entry.
1083   @param[in, out] ReservedRangeCount         Pointer to reserved range count.
1084   @param[out]     FinalRanges                Output pointer to hold split final EFI_SMRAM_DESCRIPTOR entry
1085                                              that no need to be split anymore.
1086   @param[in, out] FinalRangeCount            Pointer to final range count.
1087 
1088 **/
1089 VOID
SmmSplitSmramEntry(IN OUT EFI_SMRAM_DESCRIPTOR * RangeToCompare,IN OUT EFI_SMM_RESERVED_SMRAM_REGION * ReservedRangeToCompare,OUT EFI_SMRAM_DESCRIPTOR * Ranges,IN OUT UINTN * RangeCount,OUT EFI_SMM_RESERVED_SMRAM_REGION * ReservedRanges,IN OUT UINTN * ReservedRangeCount,OUT EFI_SMRAM_DESCRIPTOR * FinalRanges,IN OUT UINTN * FinalRangeCount)1090 SmmSplitSmramEntry (
1091   IN OUT EFI_SMRAM_DESCRIPTOR           *RangeToCompare,
1092   IN OUT EFI_SMM_RESERVED_SMRAM_REGION  *ReservedRangeToCompare,
1093   OUT    EFI_SMRAM_DESCRIPTOR           *Ranges,
1094   IN OUT UINTN                          *RangeCount,
1095   OUT    EFI_SMM_RESERVED_SMRAM_REGION  *ReservedRanges,
1096   IN OUT UINTN                          *ReservedRangeCount,
1097   OUT    EFI_SMRAM_DESCRIPTOR           *FinalRanges,
1098   IN OUT UINTN                          *FinalRangeCount
1099   )
1100 {
1101   UINT64    RangeToCompareEnd;
1102   UINT64    ReservedRangeToCompareEnd;
1103 
1104   RangeToCompareEnd         = RangeToCompare->CpuStart + RangeToCompare->PhysicalSize;
1105   ReservedRangeToCompareEnd = ReservedRangeToCompare->SmramReservedStart + ReservedRangeToCompare->SmramReservedSize;
1106 
1107   if ((RangeToCompare->CpuStart >= ReservedRangeToCompare->SmramReservedStart) &&
1108       (RangeToCompare->CpuStart < ReservedRangeToCompareEnd)) {
1109     if (RangeToCompareEnd < ReservedRangeToCompareEnd) {
1110       //
1111       // RangeToCompare  ReservedRangeToCompare
1112       //                 ----                    ----    --------------------------------------
1113       //                 |  |                    |  | -> 1. ReservedRangeToCompare
1114       // ----            |  |                    |--|    --------------------------------------
1115       // |  |            |  |                    |  |
1116       // |  |            |  |                    |  | -> 2. FinalRanges[*FinalRangeCount] and increment *FinalRangeCount
1117       // |  |            |  |                    |  |       RangeToCompare->PhysicalSize = 0
1118       // ----            |  |                    |--|    --------------------------------------
1119       //                 |  |                    |  | -> 3. ReservedRanges[*ReservedRangeCount] and increment *ReservedRangeCount
1120       //                 ----                    ----    --------------------------------------
1121       //
1122 
1123       //
1124       // 1. Update ReservedRangeToCompare.
1125       //
1126       ReservedRangeToCompare->SmramReservedSize = RangeToCompare->CpuStart - ReservedRangeToCompare->SmramReservedStart;
1127       //
1128       // 2. Update FinalRanges[FinalRangeCount] and increment *FinalRangeCount.
1129       //    Zero RangeToCompare->PhysicalSize.
1130       //
1131       FinalRanges[*FinalRangeCount].CpuStart      = RangeToCompare->CpuStart;
1132       FinalRanges[*FinalRangeCount].PhysicalStart = RangeToCompare->PhysicalStart;
1133       FinalRanges[*FinalRangeCount].RegionState   = RangeToCompare->RegionState | EFI_ALLOCATED;
1134       FinalRanges[*FinalRangeCount].PhysicalSize  = RangeToCompare->PhysicalSize;
1135       *FinalRangeCount += 1;
1136       RangeToCompare->PhysicalSize = 0;
1137       //
1138       // 3. Update ReservedRanges[*ReservedRangeCount] and increment *ReservedRangeCount.
1139       //
1140       ReservedRanges[*ReservedRangeCount].SmramReservedStart = FinalRanges[*FinalRangeCount - 1].CpuStart + FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1141       ReservedRanges[*ReservedRangeCount].SmramReservedSize  = ReservedRangeToCompareEnd - RangeToCompareEnd;
1142       *ReservedRangeCount += 1;
1143     } else {
1144       //
1145       // RangeToCompare  ReservedRangeToCompare
1146       //                 ----                    ----    --------------------------------------
1147       //                 |  |                    |  | -> 1. ReservedRangeToCompare
1148       // ----            |  |                    |--|    --------------------------------------
1149       // |  |            |  |                    |  |
1150       // |  |            |  |                    |  | -> 2. FinalRanges[*FinalRangeCount] and increment *FinalRangeCount
1151       // |  |            |  |                    |  |
1152       // |  |            ----                    |--|    --------------------------------------
1153       // |  |                                    |  | -> 3. RangeToCompare
1154       // ----                                    ----    --------------------------------------
1155       //
1156 
1157       //
1158       // 1. Update ReservedRangeToCompare.
1159       //
1160       ReservedRangeToCompare->SmramReservedSize = RangeToCompare->CpuStart - ReservedRangeToCompare->SmramReservedStart;
1161       //
1162       // 2. Update FinalRanges[FinalRangeCount] and increment *FinalRangeCount.
1163       //
1164       FinalRanges[*FinalRangeCount].CpuStart      = RangeToCompare->CpuStart;
1165       FinalRanges[*FinalRangeCount].PhysicalStart = RangeToCompare->PhysicalStart;
1166       FinalRanges[*FinalRangeCount].RegionState   = RangeToCompare->RegionState | EFI_ALLOCATED;
1167       FinalRanges[*FinalRangeCount].PhysicalSize  = ReservedRangeToCompareEnd - RangeToCompare->CpuStart;
1168       *FinalRangeCount += 1;
1169       //
1170       // 3. Update RangeToCompare.
1171       //
1172       RangeToCompare->CpuStart      += FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1173       RangeToCompare->PhysicalStart += FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1174       RangeToCompare->PhysicalSize  -= FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1175     }
1176   } else if ((ReservedRangeToCompare->SmramReservedStart >= RangeToCompare->CpuStart) &&
1177              (ReservedRangeToCompare->SmramReservedStart < RangeToCompareEnd)) {
1178     if (ReservedRangeToCompareEnd < RangeToCompareEnd) {
1179       //
1180       // RangeToCompare  ReservedRangeToCompare
1181       // ----                                    ----    --------------------------------------
1182       // |  |                                    |  | -> 1. RangeToCompare
1183       // |  |            ----                    |--|    --------------------------------------
1184       // |  |            |  |                    |  |
1185       // |  |            |  |                    |  | -> 2. FinalRanges[*FinalRangeCount] and increment *FinalRangeCount
1186       // |  |            |  |                    |  |       ReservedRangeToCompare->SmramReservedSize = 0
1187       // |  |            ----                    |--|    --------------------------------------
1188       // |  |                                    |  | -> 3. Ranges[*RangeCount] and increment *RangeCount
1189       // ----                                    ----    --------------------------------------
1190       //
1191 
1192       //
1193       // 1. Update RangeToCompare.
1194       //
1195       RangeToCompare->PhysicalSize = ReservedRangeToCompare->SmramReservedStart - RangeToCompare->CpuStart;
1196       //
1197       // 2. Update FinalRanges[FinalRangeCount] and increment *FinalRangeCount.
1198       //    ReservedRangeToCompare->SmramReservedSize = 0
1199       //
1200       FinalRanges[*FinalRangeCount].CpuStart      = ReservedRangeToCompare->SmramReservedStart;
1201       FinalRanges[*FinalRangeCount].PhysicalStart = RangeToCompare->PhysicalStart + RangeToCompare->PhysicalSize;
1202       FinalRanges[*FinalRangeCount].RegionState   = RangeToCompare->RegionState | EFI_ALLOCATED;
1203       FinalRanges[*FinalRangeCount].PhysicalSize  = ReservedRangeToCompare->SmramReservedSize;
1204       *FinalRangeCount += 1;
1205       ReservedRangeToCompare->SmramReservedSize = 0;
1206       //
1207       // 3. Update Ranges[*RangeCount] and increment *RangeCount.
1208       //
1209       Ranges[*RangeCount].CpuStart      = FinalRanges[*FinalRangeCount - 1].CpuStart + FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1210       Ranges[*RangeCount].PhysicalStart = FinalRanges[*FinalRangeCount - 1].PhysicalStart + FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1211       Ranges[*RangeCount].RegionState   = RangeToCompare->RegionState;
1212       Ranges[*RangeCount].PhysicalSize  = RangeToCompareEnd - ReservedRangeToCompareEnd;
1213       *RangeCount += 1;
1214     } else {
1215       //
1216       // RangeToCompare  ReservedRangeToCompare
1217       // ----                                    ----    --------------------------------------
1218       // |  |                                    |  | -> 1. RangeToCompare
1219       // |  |            ----                    |--|    --------------------------------------
1220       // |  |            |  |                    |  |
1221       // |  |            |  |                    |  | -> 2. FinalRanges[*FinalRangeCount] and increment *FinalRangeCount
1222       // |  |            |  |                    |  |
1223       // ----            |  |                    |--|    --------------------------------------
1224       //                 |  |                    |  | -> 3. ReservedRangeToCompare
1225       //                 ----                    ----    --------------------------------------
1226       //
1227 
1228       //
1229       // 1. Update RangeToCompare.
1230       //
1231       RangeToCompare->PhysicalSize = ReservedRangeToCompare->SmramReservedStart - RangeToCompare->CpuStart;
1232       //
1233       // 2. Update FinalRanges[FinalRangeCount] and increment *FinalRangeCount.
1234       //    ReservedRangeToCompare->SmramReservedSize = 0
1235       //
1236       FinalRanges[*FinalRangeCount].CpuStart      = ReservedRangeToCompare->SmramReservedStart;
1237       FinalRanges[*FinalRangeCount].PhysicalStart = RangeToCompare->PhysicalStart + RangeToCompare->PhysicalSize;
1238       FinalRanges[*FinalRangeCount].RegionState   = RangeToCompare->RegionState | EFI_ALLOCATED;
1239       FinalRanges[*FinalRangeCount].PhysicalSize  = RangeToCompareEnd - ReservedRangeToCompare->SmramReservedStart;
1240       *FinalRangeCount += 1;
1241       //
1242       // 3. Update ReservedRangeToCompare.
1243       //
1244       ReservedRangeToCompare->SmramReservedStart += FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1245       ReservedRangeToCompare->SmramReservedSize  -= FinalRanges[*FinalRangeCount - 1].PhysicalSize;
1246     }
1247   }
1248 }
1249 
1250 /**
1251   Returns if SMRAM range and SMRAM reserved range are overlapped.
1252 
1253   @param[in] RangeToCompare             Pointer to EFI_SMRAM_DESCRIPTOR to compare.
1254   @param[in] ReservedRangeToCompare     Pointer to EFI_SMM_RESERVED_SMRAM_REGION to compare.
1255 
1256   @retval TRUE  There is overlap.
1257   @retval FALSE There is no overlap.
1258 
1259 **/
1260 BOOLEAN
SmmIsSmramOverlap(IN EFI_SMRAM_DESCRIPTOR * RangeToCompare,IN EFI_SMM_RESERVED_SMRAM_REGION * ReservedRangeToCompare)1261 SmmIsSmramOverlap (
1262   IN EFI_SMRAM_DESCRIPTOR           *RangeToCompare,
1263   IN EFI_SMM_RESERVED_SMRAM_REGION  *ReservedRangeToCompare
1264   )
1265 {
1266   UINT64    RangeToCompareEnd;
1267   UINT64    ReservedRangeToCompareEnd;
1268 
1269   RangeToCompareEnd         = RangeToCompare->CpuStart + RangeToCompare->PhysicalSize;
1270   ReservedRangeToCompareEnd = ReservedRangeToCompare->SmramReservedStart + ReservedRangeToCompare->SmramReservedSize;
1271 
1272   if ((RangeToCompare->CpuStart >= ReservedRangeToCompare->SmramReservedStart) &&
1273       (RangeToCompare->CpuStart < ReservedRangeToCompareEnd)) {
1274     return TRUE;
1275   } else if ((ReservedRangeToCompare->SmramReservedStart >= RangeToCompare->CpuStart) &&
1276              (ReservedRangeToCompare->SmramReservedStart < RangeToCompareEnd)) {
1277     return TRUE;
1278   }
1279   return FALSE;
1280 }
1281 
1282 /**
1283   Get full SMRAM ranges.
1284 
1285   It will get SMRAM ranges from SmmAccess protocol and SMRAM reserved ranges from
1286   SmmConfiguration protocol, split the entries if there is overlap between them.
1287   It will also reserve one entry for SMM core.
1288 
1289   @param[out] FullSmramRangeCount   Output pointer to full SMRAM range count.
1290 
1291   @return Pointer to full SMRAM ranges.
1292 
1293 **/
1294 EFI_SMRAM_DESCRIPTOR *
GetFullSmramRanges(OUT UINTN * FullSmramRangeCount)1295 GetFullSmramRanges (
1296   OUT UINTN     *FullSmramRangeCount
1297   )
1298 {
1299   EFI_STATUS                        Status;
1300   EFI_SMM_CONFIGURATION_PROTOCOL    *SmmConfiguration;
1301   UINTN                             Size;
1302   UINTN                             Index;
1303   UINTN                             Index2;
1304   EFI_SMRAM_DESCRIPTOR              *FullSmramRanges;
1305   UINTN                             TempSmramRangeCount;
1306   UINTN                             AdditionSmramRangeCount;
1307   EFI_SMRAM_DESCRIPTOR              *TempSmramRanges;
1308   UINTN                             SmramRangeCount;
1309   EFI_SMRAM_DESCRIPTOR              *SmramRanges;
1310   UINTN                             SmramReservedCount;
1311   EFI_SMM_RESERVED_SMRAM_REGION     *SmramReservedRanges;
1312   UINTN                             MaxCount;
1313   BOOLEAN                           Rescan;
1314 
1315   //
1316   // Get SMM Configuration Protocol if it is present.
1317   //
1318   SmmConfiguration = NULL;
1319   Status = gBS->LocateProtocol (&gEfiSmmConfigurationProtocolGuid, NULL, (VOID **) &SmmConfiguration);
1320 
1321   //
1322   // Get SMRAM information.
1323   //
1324   Size = 0;
1325   Status = mSmmAccess->GetCapabilities (mSmmAccess, &Size, NULL);
1326   ASSERT (Status == EFI_BUFFER_TOO_SMALL);
1327 
1328   SmramRangeCount = Size / sizeof (EFI_SMRAM_DESCRIPTOR);
1329 
1330   //
1331   // Get SMRAM reserved region count.
1332   //
1333   SmramReservedCount = 0;
1334   if (SmmConfiguration != NULL) {
1335     while (SmmConfiguration->SmramReservedRegions[SmramReservedCount].SmramReservedSize != 0) {
1336       SmramReservedCount++;
1337     }
1338   }
1339 
1340   //
1341   // Reserve one entry for SMM Core in the full SMRAM ranges.
1342   //
1343   AdditionSmramRangeCount = 1;
1344   if (PcdGet64(PcdLoadModuleAtFixAddressEnable) != 0) {
1345     //
1346     // Reserve two entries for all SMM drivers and SMM Core in the full SMRAM ranges.
1347     //
1348     AdditionSmramRangeCount = 2;
1349   }
1350 
1351   if (SmramReservedCount == 0) {
1352     //
1353     // No reserved SMRAM entry from SMM Configuration Protocol.
1354     //
1355     *FullSmramRangeCount = SmramRangeCount + AdditionSmramRangeCount;
1356     Size = (*FullSmramRangeCount) * sizeof (EFI_SMRAM_DESCRIPTOR);
1357     FullSmramRanges = (EFI_SMRAM_DESCRIPTOR *) AllocateZeroPool (Size);
1358     ASSERT (FullSmramRanges != NULL);
1359 
1360     Status = mSmmAccess->GetCapabilities (mSmmAccess, &Size, FullSmramRanges);
1361     ASSERT_EFI_ERROR (Status);
1362 
1363     return FullSmramRanges;
1364   }
1365 
1366   //
1367   // Why MaxCount = X + 2 * Y?
1368   // Take Y = 1 as example below, Y > 1 case is just the iteration of Y = 1.
1369   //
1370   //   X = 1 Y = 1     MaxCount = 3 = 1 + 2 * 1
1371   //   ----            ----
1372   //   |  |  ----      |--|
1373   //   |  |  |  |  ->  |  |
1374   //   |  |  ----      |--|
1375   //   ----            ----
1376   //
1377   //   X = 2 Y = 1     MaxCount = 4 = 2 + 2 * 1
1378   //   ----            ----
1379   //   |  |            |  |
1380   //   |  |  ----      |--|
1381   //   |  |  |  |      |  |
1382   //   |--|  |  |  ->  |--|
1383   //   |  |  |  |      |  |
1384   //   |  |  ----      |--|
1385   //   |  |            |  |
1386   //   ----            ----
1387   //
1388   //   X = 3 Y = 1     MaxCount = 5 = 3 + 2 * 1
1389   //   ----            ----
1390   //   |  |            |  |
1391   //   |  |  ----      |--|
1392   //   |--|  |  |      |--|
1393   //   |  |  |  |  ->  |  |
1394   //   |--|  |  |      |--|
1395   //   |  |  ----      |--|
1396   //   |  |            |  |
1397   //   ----            ----
1398   //
1399   //   ......
1400   //
1401   MaxCount = SmramRangeCount + 2 * SmramReservedCount;
1402 
1403   Size = MaxCount * sizeof (EFI_SMM_RESERVED_SMRAM_REGION);
1404   SmramReservedRanges = (EFI_SMM_RESERVED_SMRAM_REGION *) AllocatePool (Size);
1405   ASSERT (SmramReservedRanges != NULL);
1406   for (Index = 0; Index < SmramReservedCount; Index++) {
1407     CopyMem (&SmramReservedRanges[Index], &SmmConfiguration->SmramReservedRegions[Index], sizeof (EFI_SMM_RESERVED_SMRAM_REGION));
1408   }
1409 
1410   Size = MaxCount * sizeof (EFI_SMRAM_DESCRIPTOR);
1411   TempSmramRanges = (EFI_SMRAM_DESCRIPTOR *) AllocatePool (Size);
1412   ASSERT (TempSmramRanges != NULL);
1413   TempSmramRangeCount = 0;
1414 
1415   SmramRanges = (EFI_SMRAM_DESCRIPTOR *) AllocatePool (Size);
1416   ASSERT (SmramRanges != NULL);
1417   Status = mSmmAccess->GetCapabilities (mSmmAccess, &Size, SmramRanges);
1418   ASSERT_EFI_ERROR (Status);
1419 
1420   do {
1421     Rescan = FALSE;
1422     for (Index = 0; (Index < SmramRangeCount) && !Rescan; Index++) {
1423       //
1424       // Skip zero size entry.
1425       //
1426       if (SmramRanges[Index].PhysicalSize != 0) {
1427         for (Index2 = 0; (Index2 < SmramReservedCount) && !Rescan; Index2++) {
1428           //
1429           // Skip zero size entry.
1430           //
1431           if (SmramReservedRanges[Index2].SmramReservedSize != 0) {
1432             if (SmmIsSmramOverlap (
1433                   &SmramRanges[Index],
1434                   &SmramReservedRanges[Index2]
1435                   )) {
1436               //
1437               // There is overlap, need to split entry and then rescan.
1438               //
1439               SmmSplitSmramEntry (
1440                 &SmramRanges[Index],
1441                 &SmramReservedRanges[Index2],
1442                 SmramRanges,
1443                 &SmramRangeCount,
1444                 SmramReservedRanges,
1445                 &SmramReservedCount,
1446                 TempSmramRanges,
1447                 &TempSmramRangeCount
1448                 );
1449               Rescan = TRUE;
1450             }
1451           }
1452         }
1453         if (!Rescan) {
1454           //
1455           // No any overlap, copy the entry to the temp SMRAM ranges.
1456           // Zero SmramRanges[Index].PhysicalSize = 0;
1457           //
1458           CopyMem (&TempSmramRanges[TempSmramRangeCount++], &SmramRanges[Index], sizeof (EFI_SMRAM_DESCRIPTOR));
1459           SmramRanges[Index].PhysicalSize = 0;
1460         }
1461       }
1462     }
1463   } while (Rescan);
1464   ASSERT (TempSmramRangeCount <= MaxCount);
1465 
1466   //
1467   // Sort the entries
1468   //
1469   FullSmramRanges = AllocateZeroPool ((TempSmramRangeCount + AdditionSmramRangeCount) * sizeof (EFI_SMRAM_DESCRIPTOR));
1470   ASSERT (FullSmramRanges != NULL);
1471   *FullSmramRangeCount = 0;
1472   do {
1473     for (Index = 0; Index < TempSmramRangeCount; Index++) {
1474       if (TempSmramRanges[Index].PhysicalSize != 0) {
1475         break;
1476       }
1477     }
1478     ASSERT (Index < TempSmramRangeCount);
1479     for (Index2 = 0; Index2 < TempSmramRangeCount; Index2++) {
1480       if ((Index2 != Index) && (TempSmramRanges[Index2].PhysicalSize != 0) && (TempSmramRanges[Index2].CpuStart < TempSmramRanges[Index].CpuStart)) {
1481         Index = Index2;
1482       }
1483     }
1484     CopyMem (&FullSmramRanges[*FullSmramRangeCount], &TempSmramRanges[Index], sizeof (EFI_SMRAM_DESCRIPTOR));
1485     *FullSmramRangeCount += 1;
1486     TempSmramRanges[Index].PhysicalSize = 0;
1487   } while (*FullSmramRangeCount < TempSmramRangeCount);
1488   ASSERT (*FullSmramRangeCount == TempSmramRangeCount);
1489   *FullSmramRangeCount += AdditionSmramRangeCount;
1490 
1491   FreePool (SmramRanges);
1492   FreePool (SmramReservedRanges);
1493   FreePool (TempSmramRanges);
1494 
1495   return FullSmramRanges;
1496 }
1497 
1498 /**
1499   The Entry Point for SMM IPL
1500 
1501   Load SMM Core into SMRAM, register SMM Core entry point for SMIs, install
1502   SMM Base 2 Protocol and SMM Communication Protocol, and register for the
1503   critical events required to coordinate between DXE and SMM environments.
1504 
1505   @param  ImageHandle    The firmware allocated handle for the EFI image.
1506   @param  SystemTable    A pointer to the EFI System Table.
1507 
1508   @retval EFI_SUCCESS    The entry point is executed successfully.
1509   @retval Other          Some error occurred when executing this entry point.
1510 
1511 **/
1512 EFI_STATUS
1513 EFIAPI
SmmIplEntry(IN EFI_HANDLE ImageHandle,IN EFI_SYSTEM_TABLE * SystemTable)1514 SmmIplEntry (
1515   IN EFI_HANDLE        ImageHandle,
1516   IN EFI_SYSTEM_TABLE  *SystemTable
1517   )
1518 {
1519   EFI_STATUS                      Status;
1520   UINTN                           Index;
1521   UINT64                          MaxSize;
1522   VOID                            *Registration;
1523   UINT64                          SmmCodeSize;
1524   EFI_LOAD_FIXED_ADDRESS_CONFIGURATION_TABLE    *LMFAConfigurationTable;
1525   EFI_CPU_ARCH_PROTOCOL           *CpuArch;
1526   EFI_STATUS                      SetAttrStatus;
1527   EFI_SMRAM_DESCRIPTOR            *SmramRangeSmmDriver;
1528 
1529   //
1530   // Fill in the image handle of the SMM IPL so the SMM Core can use this as the
1531   // ParentImageHandle field of the Load Image Protocol for all SMM Drivers loaded
1532   // by the SMM Core
1533   //
1534   mSmmCorePrivateData.SmmIplImageHandle = ImageHandle;
1535 
1536   //
1537   // Get SMM Access Protocol
1538   //
1539   Status = gBS->LocateProtocol (&gEfiSmmAccess2ProtocolGuid, NULL, (VOID **)&mSmmAccess);
1540   ASSERT_EFI_ERROR (Status);
1541 
1542   //
1543   // Get SMM Control2 Protocol
1544   //
1545   Status = gBS->LocateProtocol (&gEfiSmmControl2ProtocolGuid, NULL, (VOID **)&mSmmControl2);
1546   ASSERT_EFI_ERROR (Status);
1547 
1548   gSmmCorePrivate->SmramRanges = GetFullSmramRanges (&gSmmCorePrivate->SmramRangeCount);
1549 
1550   //
1551   // Open all SMRAM ranges
1552   //
1553   Status = mSmmAccess->Open (mSmmAccess);
1554   ASSERT_EFI_ERROR (Status);
1555 
1556   //
1557   // Print debug message that the SMRAM window is now open.
1558   //
1559   DEBUG ((DEBUG_INFO, "SMM IPL opened SMRAM window\n"));
1560 
1561   //
1562   // Find the largest SMRAM range between 1MB and 4GB that is at least 256KB - 4K in size
1563   //
1564   mCurrentSmramRange = NULL;
1565   for (Index = 0, MaxSize = SIZE_256KB - EFI_PAGE_SIZE; Index < gSmmCorePrivate->SmramRangeCount; Index++) {
1566     //
1567     // Skip any SMRAM region that is already allocated, needs testing, or needs ECC initialization
1568     //
1569     if ((gSmmCorePrivate->SmramRanges[Index].RegionState & (EFI_ALLOCATED | EFI_NEEDS_TESTING | EFI_NEEDS_ECC_INITIALIZATION)) != 0) {
1570       continue;
1571     }
1572 
1573     if (gSmmCorePrivate->SmramRanges[Index].CpuStart >= BASE_1MB) {
1574       if ((gSmmCorePrivate->SmramRanges[Index].CpuStart + gSmmCorePrivate->SmramRanges[Index].PhysicalSize - 1) <= MAX_ADDRESS) {
1575         if (gSmmCorePrivate->SmramRanges[Index].PhysicalSize >= MaxSize) {
1576           MaxSize = gSmmCorePrivate->SmramRanges[Index].PhysicalSize;
1577           mCurrentSmramRange = &gSmmCorePrivate->SmramRanges[Index];
1578         }
1579       }
1580     }
1581   }
1582 
1583   if (mCurrentSmramRange != NULL) {
1584     //
1585     // Print debug message showing SMRAM window that will be used by SMM IPL and SMM Core
1586     //
1587     DEBUG ((DEBUG_INFO, "SMM IPL found SMRAM window %p - %p\n",
1588       (VOID *)(UINTN)mCurrentSmramRange->CpuStart,
1589       (VOID *)(UINTN)(mCurrentSmramRange->CpuStart + mCurrentSmramRange->PhysicalSize - 1)
1590       ));
1591 
1592     GetSmramCacheRange (mCurrentSmramRange, &mSmramCacheBase, &mSmramCacheSize);
1593     //
1594     // If CPU AP is present, attempt to set SMRAM cacheability to WB
1595     // Note that it is expected that cacheability of SMRAM has been set to WB if CPU AP
1596     // is not available here.
1597     //
1598     CpuArch = NULL;
1599     Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, (VOID **)&CpuArch);
1600     if (!EFI_ERROR (Status)) {
1601       Status = gDS->SetMemorySpaceAttributes(
1602                       mSmramCacheBase,
1603                       mSmramCacheSize,
1604                       EFI_MEMORY_WB
1605                       );
1606       if (EFI_ERROR (Status)) {
1607         DEBUG ((DEBUG_WARN, "SMM IPL failed to set SMRAM window to EFI_MEMORY_WB\n"));
1608       }
1609     }
1610     //
1611     // if Loading module at Fixed Address feature is enabled, save the SMRAM base to Load
1612     // Modules At Fixed Address Configuration Table.
1613     //
1614     if (PcdGet64(PcdLoadModuleAtFixAddressEnable) != 0) {
1615       //
1616       // Build tool will calculate the smm code size and then patch the PcdLoadFixAddressSmmCodePageNumber
1617       //
1618       SmmCodeSize = LShiftU64 (PcdGet32(PcdLoadFixAddressSmmCodePageNumber), EFI_PAGE_SHIFT);
1619       //
1620       // The SMRAM available memory is assumed to be larger than SmmCodeSize
1621       //
1622       ASSERT (mCurrentSmramRange->PhysicalSize > SmmCodeSize);
1623       //
1624       // Retrieve Load modules At fixed address configuration table and save the SMRAM base.
1625       //
1626       Status = EfiGetSystemConfigurationTable (
1627                 &gLoadFixedAddressConfigurationTableGuid,
1628                (VOID **) &LMFAConfigurationTable
1629                );
1630       if (!EFI_ERROR (Status) && LMFAConfigurationTable != NULL) {
1631         LMFAConfigurationTable->SmramBase = mCurrentSmramRange->CpuStart;
1632         //
1633         // Print the SMRAM base
1634         //
1635         DEBUG ((EFI_D_INFO, "LOADING MODULE FIXED INFO: TSEG BASE is %x. \n", LMFAConfigurationTable->SmramBase));
1636       }
1637 
1638       //
1639       // Fill the Smram range for all SMM code
1640       //
1641       SmramRangeSmmDriver = &gSmmCorePrivate->SmramRanges[gSmmCorePrivate->SmramRangeCount - 2];
1642       SmramRangeSmmDriver->CpuStart      = mCurrentSmramRange->CpuStart;
1643       SmramRangeSmmDriver->PhysicalStart = mCurrentSmramRange->PhysicalStart;
1644       SmramRangeSmmDriver->RegionState   = mCurrentSmramRange->RegionState | EFI_ALLOCATED;
1645       SmramRangeSmmDriver->PhysicalSize  = SmmCodeSize;
1646 
1647       mCurrentSmramRange->PhysicalSize  -= SmmCodeSize;
1648       mCurrentSmramRange->CpuStart       = mCurrentSmramRange->CpuStart + SmmCodeSize;
1649       mCurrentSmramRange->PhysicalStart  = mCurrentSmramRange->PhysicalStart + SmmCodeSize;
1650     }
1651     //
1652     // Load SMM Core into SMRAM and execute it from SMRAM
1653     //
1654     Status = ExecuteSmmCoreFromSmram (
1655                mCurrentSmramRange,
1656                &gSmmCorePrivate->SmramRanges[gSmmCorePrivate->SmramRangeCount - 1],
1657                gSmmCorePrivate
1658                );
1659     if (EFI_ERROR (Status)) {
1660       //
1661       // Print error message that the SMM Core failed to be loaded and executed.
1662       //
1663       DEBUG ((DEBUG_ERROR, "SMM IPL could not load and execute SMM Core from SMRAM\n"));
1664 
1665       //
1666       // Attempt to reset SMRAM cacheability to UC
1667       //
1668       if (CpuArch != NULL) {
1669         SetAttrStatus = gDS->SetMemorySpaceAttributes(
1670                                mSmramCacheBase,
1671                                mSmramCacheSize,
1672                                EFI_MEMORY_UC
1673                                );
1674         if (EFI_ERROR (SetAttrStatus)) {
1675           DEBUG ((DEBUG_WARN, "SMM IPL failed to reset SMRAM window to EFI_MEMORY_UC\n"));
1676         }
1677       }
1678     }
1679   } else {
1680     //
1681     // Print error message that there are not enough SMRAM resources to load the SMM Core.
1682     //
1683     DEBUG ((DEBUG_ERROR, "SMM IPL could not find a large enough SMRAM region to load SMM Core\n"));
1684   }
1685 
1686   //
1687   // If the SMM Core could not be loaded then close SMRAM window, free allocated
1688   // resources, and return an error so SMM IPL will be unloaded.
1689   //
1690   if (mCurrentSmramRange == NULL || EFI_ERROR (Status)) {
1691     //
1692     // Close all SMRAM ranges
1693     //
1694     Status = mSmmAccess->Close (mSmmAccess);
1695     ASSERT_EFI_ERROR (Status);
1696 
1697     //
1698     // Print debug message that the SMRAM window is now closed.
1699     //
1700     DEBUG ((DEBUG_INFO, "SMM IPL closed SMRAM window\n"));
1701 
1702     //
1703     // Free all allocated resources
1704     //
1705     FreePool (gSmmCorePrivate->SmramRanges);
1706 
1707     return EFI_UNSUPPORTED;
1708   }
1709 
1710   //
1711   // Install SMM Base2 Protocol and SMM Communication Protocol
1712   //
1713   Status = gBS->InstallMultipleProtocolInterfaces (
1714                   &mSmmIplHandle,
1715                   &gEfiSmmBase2ProtocolGuid,         &mSmmBase2,
1716                   &gEfiSmmCommunicationProtocolGuid, &mSmmCommunication,
1717                   NULL
1718                   );
1719   ASSERT_EFI_ERROR (Status);
1720 
1721   //
1722   // Create the set of protocol and event notififcations that the SMM IPL requires
1723   //
1724   for (Index = 0; mSmmIplEvents[Index].NotifyFunction != NULL; Index++) {
1725     if (mSmmIplEvents[Index].Protocol) {
1726       mSmmIplEvents[Index].Event = EfiCreateProtocolNotifyEvent (
1727                                      mSmmIplEvents[Index].Guid,
1728                                      mSmmIplEvents[Index].NotifyTpl,
1729                                      mSmmIplEvents[Index].NotifyFunction,
1730                                      mSmmIplEvents[Index].NotifyContext,
1731                                     &Registration
1732                                     );
1733     } else {
1734       Status = gBS->CreateEventEx (
1735                       EVT_NOTIFY_SIGNAL,
1736                       mSmmIplEvents[Index].NotifyTpl,
1737                       mSmmIplEvents[Index].NotifyFunction,
1738                       mSmmIplEvents[Index].NotifyContext,
1739                       mSmmIplEvents[Index].Guid,
1740                       &mSmmIplEvents[Index].Event
1741                       );
1742       ASSERT_EFI_ERROR (Status);
1743     }
1744   }
1745 
1746   return EFI_SUCCESS;
1747 }
1748