IntelFrameworkPkg/Library/PeiHobLibFramework/HobLib.c

   1 /** @file
   2  Instance of HOB Library using PEI Services.
   3
   4  HOB Library implementation that uses PEI Services to retrieve the HOB List.
   5  This library instance uses EFI_HOB_TYPE_CV defined in Intel framework HOB specification v0.9
   6  to implement HobLib BuildCvHob() API.
   7
   8 Copyright (c) 2007 - 2009, Intel Corporation<BR>
   9 All rights reserved. This program and the accompanying materials
  10 are licensed and made available under the terms and conditions of the BSD License
  11 which accompanies this distribution.  The full text of the license may be found at
  12 http://opensource.org/licenses/bsd-license.php
  13
  14 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  15 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  16
  17 **/
  18
  19 #include <PiPei.h>
  20 #include <FrameworkPei.h>
  21
  22 #include <Guid/MemoryAllocationHob.h>
  23
  24 #include <Library/HobLib.h>
  25 #include <Library/DebugLib.h>
  26 #include <Library/PeiServicesLib.h>
  27 #include <Library/BaseMemoryLib.h>
  28
  29 /**
  30   Returns the pointer to the HOB list.
  31
  32   This function returns the pointer to first HOB in the list.
  33   For PEI phase, the PEI service GetHobList() can be used to retrieve the pointer
  34   to the HOB list.  For the DXE phase, the HOB list pointer can be retrieved through
  35   the EFI System Table by looking up theHOB list GUID in the System Configuration Table.
  36   Since the System Configuration Table does not exist that the time the DXE Core is
  37   launched, the DXE Core uses a global variable from the DXE Core Entry Point Library
  38   to manage the pointer to the HOB list.
  39
  40   If the pointer to the HOB list is NULL, then ASSERT().
  41
  42   @return The pointer to the HOB list.
  43
  44 **/
  45 VOID *
  46 EFIAPI
  47 GetHobList (
  48   VOID
  49   )
  50 {
  51   EFI_STATUS            Status;
  52   VOID                  *HobList;
  53
  54   Status = PeiServicesGetHobList (&HobList);
  55   ASSERT_EFI_ERROR (Status);
  56   ASSERT (HobList != NULL);
  57
  58   return HobList;
  59 }
  60
  61 /**
  62   Returns the next instance of a HOB type from the starting HOB.
  63
  64   This function searches the first instance of a HOB type from the starting HOB pointer.
  65   If there does not exist such HOB type from the starting HOB pointer, it will return NULL.
  66   In contrast with macro GET_NEXT_HOB(), this function does not skip the starting HOB pointer
  67   unconditionally: it returns HobStart back if HobStart itself meets the requirement;
  68   caller is required to use GET_NEXT_HOB() if it wishes to skip current HobStart.
  69
  70   If HobStart is NULL, then ASSERT().
  71
  72   @param  Type          The HOB type to return.
  73   @param  HobStart      The starting HOB pointer to search from.
  74
  75   @return The next instance of a HOB type from the starting HOB.
  76
  77 **/
  78 VOID *
  79 EFIAPI
  80 GetNextHob (
  81   IN UINT16                 Type,
  82   IN CONST VOID             *HobStart
  83   )
  84 {
  85   EFI_PEI_HOB_POINTERS  Hob;
  86
  87   ASSERT (HobStart != NULL);
  88
  89   Hob.Raw = (UINT8 *) HobStart;
  90   //
  91   // Parse the HOB list until end of list or matching type is found.
  92   //
  93   while (!END_OF_HOB_LIST (Hob)) {
  94     if (Hob.Header->HobType == Type) {
  95       return Hob.Raw;
  96     }
  97     Hob.Raw = GET_NEXT_HOB (Hob);
  98   }
  99   return NULL;
 100 }
 101
 102 /**
 103   Returns the first instance of a HOB type among the whole HOB list.
 104
 105   This function searches the first instance of a HOB type among the whole HOB list.
 106   If there does not exist such HOB type in the HOB list, it will return NULL.
 107
 108   If the pointer to the HOB list is NULL, then ASSERT().
 109
 110   @param  Type          The HOB type to return.
 111
 112   @return The next instance of a HOB type from the starting HOB.
 113
 114 **/
 115 VOID *
 116 EFIAPI
 117 GetFirstHob (
 118   IN UINT16                 Type
 119   )
 120 {
 121   VOID      *HobList;
 122
 123   HobList = GetHobList ();
 124   return GetNextHob (Type, HobList);
 125 }
 126
 127 /**
 128   Returns the next instance of the matched GUID HOB from the starting HOB.
 129
 130   This function searches the first instance of a HOB from the starting HOB pointer.
 131   Such HOB should satisfy two conditions:
 132   its HOB type is EFI_HOB_TYPE_GUID_EXTENSION and its GUID Name equals to the input Guid.
 133   If there does not exist such HOB from the starting HOB pointer, it will return NULL.
 134   Caller is required to apply GET_GUID_HOB_DATA () and GET_GUID_HOB_DATA_SIZE ()
 135   to extract the data section and its size info respectively.
 136   In contrast with macro GET_NEXT_HOB(), this function does not skip the starting HOB pointer
 137   unconditionally: it returns HobStart back if HobStart itself meets the requirement;
 138   caller is required to use GET_NEXT_HOB() if it wishes to skip current HobStart.
 139
 140   If Guid is NULL, then ASSERT().
 141   If HobStart is NULL, then ASSERT().
 142
 143   @param  Guid          The GUID to match with in the HOB list.
 144   @param  HobStart      A pointer to a Guid.
 145
 146   @return The next instance of the matched GUID HOB from the starting HOB.
 147
 148 **/
 149 VOID *
 150 EFIAPI
 151 GetNextGuidHob (
 152   IN CONST EFI_GUID         *Guid,
 153   IN CONST VOID             *HobStart
 154   )
 155 {
 156   EFI_PEI_HOB_POINTERS  GuidHob;
 157
 158   GuidHob.Raw = (UINT8 *) HobStart;
 159   while ((GuidHob.Raw = GetNextHob (EFI_HOB_TYPE_GUID_EXTENSION, GuidHob.Raw)) != NULL) {
 160     if (CompareGuid (Guid, &GuidHob.Guid->Name)) {
 161       break;
 162     }
 163     GuidHob.Raw = GET_NEXT_HOB (GuidHob);
 164   }
 165   return GuidHob.Raw;
 166 }
 167
 168 /**
 169   Returns the first instance of the matched GUID HOB among the whole HOB list.
 170
 171   This function searches the first instance of a HOB among the whole HOB list.
 172   Such HOB should satisfy two conditions:
 173   its HOB type is EFI_HOB_TYPE_GUID_EXTENSION and its GUID Name equals to the input Guid.
 174   If there does not exist such HOB from the starting HOB pointer, it will return NULL.
 175   Caller is required to apply GET_GUID_HOB_DATA () and GET_GUID_HOB_DATA_SIZE ()
 176   to extract the data section and its size info respectively.
 177
 178   If the pointer to the HOB list is NULL, then ASSERT().
 179   If Guid is NULL, then ASSERT().
 180
 181   @param  Guid          The GUID to match with in the HOB list.
 182
 183   @return The first instance of the matched GUID HOB among the whole HOB list.
 184
 185 **/
 186 VOID *
 187 EFIAPI
 188 GetFirstGuidHob (
 189   IN CONST EFI_GUID         *Guid
 190   )
 191 {
 192   VOID      *HobList;
 193
 194   HobList = GetHobList ();
 195   return GetNextGuidHob (Guid, HobList);
 196 }
 197
 198 /**
 199   Get the system boot mode from the HOB list.
 200
 201   This function returns the system boot mode information from the
 202   PHIT HOB in HOB list.
 203
 204   If the pointer to the HOB list is NULL, then ASSERT().
 205
 206   @param  VOID
 207
 208   @return The Boot Mode.
 209
 210 **/
 211 EFI_BOOT_MODE
 212 EFIAPI
 213 GetBootModeHob (
 214   VOID
 215   )
 216 {
 217   EFI_STATUS             Status;
 218   EFI_BOOT_MODE          BootMode;
 219
 220   Status = PeiServicesGetBootMode (&BootMode);
 221   ASSERT_EFI_ERROR (Status);
 222
 223   return BootMode;
 224 }
 225
 226 /**
 227   Adds a new HOB to the HOB List.
 228
 229   This internal function enables PEIMs to create various types of HOBs.
 230
 231   @param  Type          Type of the new HOB.
 232   @param  Length        Length of the new HOB to allocate.
 233
 234   @return The address of new HOB.
 235
 236 **/
 237 VOID *
 238 EFIAPI
 239 InternalPeiCreateHob (
 240   IN UINT16                      Type,
 241   IN UINT16                      Length
 242   )
 243 {
 244   EFI_STATUS        Status;
 245   VOID              *Hob;
 246
 247   Status = PeiServicesCreateHob (Type, Length, &Hob);
 248   //
 249   // Assume the process of HOB building is always successful.
 250   //
 251   ASSERT_EFI_ERROR (Status);
 252   return Hob;
 253 }
 254
 255 /**
 256   Builds a HOB for a loaded PE32 module.
 257
 258   This function builds a HOB for a loaded PE32 module.
 259   It can only be invoked during PEI phase;
 260   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 261
 262   If ModuleName is NULL, then ASSERT().
 263   If there is no additional space for HOB creation, then ASSERT().
 264
 265   @param  ModuleName              The GUID File Name of the module.
 266   @param  MemoryAllocationModule  The 64 bit physical address of the module.
 267   @param  ModuleLength            The length of the module in bytes.
 268   @param  EntryPoint              The 64 bit physical address of the module entry point.
 269
 270 **/
 271 VOID
 272 EFIAPI
 273 BuildModuleHob (
 274   IN CONST EFI_GUID         *ModuleName,
 275   IN EFI_PHYSICAL_ADDRESS   MemoryAllocationModule,
 276   IN UINT64                 ModuleLength,
 277   IN EFI_PHYSICAL_ADDRESS   EntryPoint
 278   )
 279 {
 280   EFI_HOB_MEMORY_ALLOCATION_MODULE  *Hob;
 281
 282   ASSERT (((MemoryAllocationModule & (EFI_PAGE_SIZE - 1)) == 0) &&
 283           ((ModuleLength & (EFI_PAGE_SIZE - 1)) == 0));
 284
 285   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, sizeof (EFI_HOB_MEMORY_ALLOCATION_MODULE));
 286
 287   CopyGuid (&(Hob->MemoryAllocationHeader.Name), &gEfiHobMemoryAllocModuleGuid);
 288   Hob->MemoryAllocationHeader.MemoryBaseAddress = MemoryAllocationModule;
 289   Hob->MemoryAllocationHeader.MemoryLength      = ModuleLength;
 290   Hob->MemoryAllocationHeader.MemoryType        = EfiBootServicesCode;
 291
 292   //
 293   // Zero the reserved space to match HOB spec
 294   //
 295   ZeroMem (Hob->MemoryAllocationHeader.Reserved, sizeof (Hob->MemoryAllocationHeader.Reserved));
 296
 297   CopyGuid (&Hob->ModuleName, ModuleName);
 298   Hob->EntryPoint = EntryPoint;
 299 }
 300
 301 /**
 302   Builds a HOB that describes a chunk of system memory.
 303
 304   This function builds a HOB that describes a chunk of system memory.
 305   It can only be invoked during PEI phase;
 306   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 307
 308   If there is no additional space for HOB creation, then ASSERT().
 309
 310   @param  ResourceType        The type of resource described by this HOB.
 311   @param  ResourceAttribute   The resource attributes of the memory described by this HOB.
 312   @param  PhysicalStart       The 64 bit physical address of memory described by this HOB.
 313   @param  NumberOfBytes       The length of the memory described by this HOB in bytes.
 314
 315 **/
 316 VOID
 317 EFIAPI
 318 BuildResourceDescriptorHob (
 319   IN EFI_RESOURCE_TYPE            ResourceType,
 320   IN EFI_RESOURCE_ATTRIBUTE_TYPE  ResourceAttribute,
 321   IN EFI_PHYSICAL_ADDRESS         PhysicalStart,
 322   IN UINT64                       NumberOfBytes
 323   )
 324 {
 325   EFI_HOB_RESOURCE_DESCRIPTOR  *Hob;
 326
 327   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_RESOURCE_DESCRIPTOR, sizeof (EFI_HOB_RESOURCE_DESCRIPTOR));
 328
 329   Hob->ResourceType      = ResourceType;
 330   Hob->ResourceAttribute = ResourceAttribute;
 331   Hob->PhysicalStart     = PhysicalStart;
 332   Hob->ResourceLength    = NumberOfBytes;
 333 }
 334
 335 /**
 336   Builds a customized HOB tagged with a GUID for identification and returns
 337   the start address of GUID HOB data.
 338
 339   This function builds a customized HOB tagged with a GUID for identification
 340   and returns the start address of GUID HOB data so that caller can fill the customized data.
 341   The HOB Header and Name field is already stripped.
 342   It can only be invoked during PEI phase;
 343   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 344
 345   If Guid is NULL, then ASSERT().
 346   If there is no additional space for HOB creation, then ASSERT().
 347   If DataLength >= (0x10000 - sizeof (EFI_HOB_GUID_TYPE)), then ASSERT().
 348
 349   @param  Guid          The GUID to tag the customized HOB.
 350   @param  DataLength    The size of the data payload for the GUID HOB.
 351
 352   @return The start address of GUID HOB data.
 353
 354 **/
 355 VOID *
 356 EFIAPI
 357 BuildGuidHob (
 358   IN CONST EFI_GUID              *Guid,
 359   IN UINTN                       DataLength
 360   )
 361 {
 362   EFI_HOB_GUID_TYPE *Hob;
 363
 364   //
 365   // Make sure that data length is not too long.
 366   //
 367   ASSERT (DataLength <= (0xffff - sizeof (EFI_HOB_GUID_TYPE)));
 368
 369   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_GUID_EXTENSION, (UINT16) (sizeof (EFI_HOB_GUID_TYPE) + DataLength));
 370   CopyGuid (&Hob->Name, Guid);
 371   return Hob + 1;
 372 }
 373
 374 /**
 375   Builds a customized HOB tagged with a GUID for identification, copies the input data to the HOB
 376   data field, and returns the start address of the GUID HOB data.
 377
 378   This function builds a customized HOB tagged with a GUID for identification and copies the input
 379   data to the HOB data field and returns the start address of the GUID HOB data.  It can only be
 380   invoked during PEI phase; for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 381   The HOB Header and Name field is already stripped.
 382   It can only be invoked during PEI phase;
 383   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 384
 385   If Guid is NULL, then ASSERT().
 386   If Data is NULL and DataLength > 0, then ASSERT().
 387   If there is no additional space for HOB creation, then ASSERT().
 388   If DataLength >= (0x10000 - sizeof (EFI_HOB_GUID_TYPE)), then ASSERT().
 389
 390   @param  Guid          The GUID to tag the customized HOB.
 391   @param  Data          The data to be copied into the data field of the GUID HOB.
 392   @param  DataLength    The size of the data payload for the GUID HOB.
 393
 394   @return The start address of GUID HOB data.
 395
 396 **/
 397 VOID *
 398 EFIAPI
 399 BuildGuidDataHob (
 400   IN CONST EFI_GUID              *Guid,
 401   IN VOID                        *Data,
 402   IN UINTN                       DataLength
 403   )
 404 {
 405   VOID  *HobData;
 406
 407   ASSERT (Data != NULL || DataLength == 0);
 408
 409   HobData = BuildGuidHob (Guid, DataLength);
 410
 411   return CopyMem (HobData, Data, DataLength);
 412 }
 413
 414 /**
 415   Builds a Firmware Volume HOB.
 416
 417   This function builds a Firmware Volume HOB.
 418   It can only be invoked during PEI phase;
 419   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 420
 421   If there is no additional space for HOB creation, then ASSERT().
 422
 423   @param  BaseAddress   The base address of the Firmware Volume.
 424   @param  Length        The size of the Firmware Volume in bytes.
 425
 426 **/
 427 VOID
 428 EFIAPI
 429 BuildFvHob (
 430   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 431   IN UINT64                      Length
 432   )
 433 {
 434   EFI_HOB_FIRMWARE_VOLUME  *Hob;
 435
 436   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_FV, sizeof (EFI_HOB_FIRMWARE_VOLUME));
 437
 438   Hob->BaseAddress = BaseAddress;
 439   Hob->Length      = Length;
 440 }
 441
 442 /**
 443   Builds a EFI_HOB_TYPE_FV2 HOB.
 444
 445   This function builds a EFI_HOB_TYPE_FV2 HOB.
 446   It can only be invoked during PEI phase;
 447   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 448
 449   If there is no additional space for HOB creation, then ASSERT().
 450
 451   @param  BaseAddress   The base address of the Firmware Volume.
 452   @param  Length        The size of the Firmware Volume in bytes.
 453   @param  FvName        The name of the Firmware Volume.
 454   @param  FileName      The name of the file.
 455
 456 **/
 457 VOID
 458 EFIAPI
 459 BuildFv2Hob (
 460   IN          EFI_PHYSICAL_ADDRESS        BaseAddress,
 461   IN          UINT64                      Length,
 462   IN CONST    EFI_GUID                    *FvName,
 463   IN CONST    EFI_GUID                    *FileName
 464   )
 465 {
 466   EFI_HOB_FIRMWARE_VOLUME2  *Hob;
 467
 468   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_FV2, sizeof (EFI_HOB_FIRMWARE_VOLUME2));
 469
 470   Hob->BaseAddress = BaseAddress;
 471   Hob->Length      = Length;
 472   CopyGuid (&Hob->FvName, FvName);
 473   CopyGuid (&Hob->FileName, FileName);
 474 }
 475
 476 /**
 477   Builds a Capsule Volume HOB.
 478
 479   This function builds a Capsule Volume HOB.
 480   It can only be invoked during PEI phase;
 481   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 482
 483   If there is no additional space for HOB creation, then ASSERT().
 484
 485   @param  BaseAddress   The base address of the Capsule Volume.
 486   @param  Length        The size of the Capsule Volume in bytes.
 487
 488 **/
 489 VOID
 490 EFIAPI
 491 BuildCvHob (
 492   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 493   IN UINT64                      Length
 494   )
 495 {
 496   EFI_HOB_CAPSULE_VOLUME     *Hob;
 497
 498   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_CV, sizeof (EFI_HOB_CAPSULE_VOLUME));
 499
 500   Hob->BaseAddress = BaseAddress;
 501   Hob->Length      = Length;
 502 }
 503
 504 /**
 505   Builds a HOB for the CPU.
 506
 507   This function builds a HOB for the CPU.
 508   It can only be invoked during PEI phase;
 509   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 510
 511   If there is no additional space for HOB creation, then ASSERT().
 512
 513   @param  SizeOfMemorySpace   The maximum physical memory addressability of the processor.
 514   @param  SizeOfIoSpace       The maximum physical I/O addressability of the processor.
 515
 516 **/
 517 VOID
 518 EFIAPI
 519 BuildCpuHob (
 520   IN UINT8                       SizeOfMemorySpace,
 521   IN UINT8                       SizeOfIoSpace
 522   )
 523 {
 524   EFI_HOB_CPU  *Hob;
 525
 526   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_CPU, sizeof (EFI_HOB_CPU));
 527
 528   Hob->SizeOfMemorySpace = SizeOfMemorySpace;
 529   Hob->SizeOfIoSpace     = SizeOfIoSpace;
 530
 531   //
 532   // Zero the reserved space to match HOB spec
 533   //
 534   ZeroMem (Hob->Reserved, sizeof (Hob->Reserved));
 535 }
 536
 537 /**
 538   Builds a HOB for the Stack.
 539
 540   This function builds a HOB for the stack.
 541   It can only be invoked during PEI phase;
 542   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 543
 544   If there is no additional space for HOB creation, then ASSERT().
 545
 546   @param  BaseAddress   The 64 bit physical address of the Stack.
 547   @param  Length        The length of the stack in bytes.
 548
 549 **/
 550 VOID
 551 EFIAPI
 552 BuildStackHob (
 553   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 554   IN UINT64                      Length
 555   )
 556 {
 557   EFI_HOB_MEMORY_ALLOCATION_STACK  *Hob;
 558
 559   ASSERT (((BaseAddress & (EFI_PAGE_SIZE - 1)) == 0) &&
 560           ((Length & (EFI_PAGE_SIZE - 1)) == 0));
 561
 562   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, sizeof (EFI_HOB_MEMORY_ALLOCATION_STACK));
 563
 564   CopyGuid (&(Hob->AllocDescriptor.Name), &gEfiHobMemoryAllocStackGuid);
 565   Hob->AllocDescriptor.MemoryBaseAddress = BaseAddress;
 566   Hob->AllocDescriptor.MemoryLength      = Length;
 567   Hob->AllocDescriptor.MemoryType        = EfiBootServicesData;
 568
 569   //
 570   // Zero the reserved space to match HOB spec
 571   //
 572   ZeroMem (Hob->AllocDescriptor.Reserved, sizeof (Hob->AllocDescriptor.Reserved));
 573 }
 574
 575 /**
 576   Builds a HOB for the BSP store.
 577
 578   This function builds a HOB for BSP store.
 579   It can only be invoked during PEI phase;
 580   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 581
 582   If there is no additional space for HOB creation, then ASSERT().
 583
 584   @param  BaseAddress   The 64 bit physical address of the BSP.
 585   @param  Length        The length of the BSP store in bytes.
 586   @param  MemoryType    Type of memory allocated by this HOB.
 587
 588 **/
 589 VOID
 590 EFIAPI
 591 BuildBspStoreHob (
 592   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 593   IN UINT64                      Length,
 594   IN EFI_MEMORY_TYPE             MemoryType
 595   )
 596 {
 597   EFI_HOB_MEMORY_ALLOCATION_BSP_STORE  *Hob;
 598
 599   ASSERT (((BaseAddress & (EFI_PAGE_SIZE - 1)) == 0) &&
 600           ((Length & (EFI_PAGE_SIZE - 1)) == 0));
 601
 602   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, sizeof (EFI_HOB_MEMORY_ALLOCATION_BSP_STORE));
 603
 604   CopyGuid (&(Hob->AllocDescriptor.Name), &gEfiHobMemoryAllocBspStoreGuid);
 605   Hob->AllocDescriptor.MemoryBaseAddress = BaseAddress;
 606   Hob->AllocDescriptor.MemoryLength      = Length;
 607   Hob->AllocDescriptor.MemoryType        = MemoryType;
 608
 609   //
 610   // Zero the reserved space to match HOB spec
 611   //
 612   ZeroMem (Hob->AllocDescriptor.Reserved, sizeof (Hob->AllocDescriptor.Reserved));
 613 }
 614
 615 /**
 616   Builds a HOB for the memory allocation.
 617
 618   This function builds a HOB for the memory allocation.
 619   It can only be invoked during PEI phase;
 620   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 621
 622   If there is no additional space for HOB creation, then ASSERT().
 623
 624   @param  BaseAddress   The 64 bit physical address of the memory.
 625   @param  Length        The length of the memory allocation in bytes.
 626   @param  MemoryType    Type of memory allocated by this HOB.
 627
 628 **/
 629 VOID
 630 EFIAPI
 631 BuildMemoryAllocationHob (
 632   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 633   IN UINT64                      Length,
 634   IN EFI_MEMORY_TYPE             MemoryType
 635   )
 636 {
 637   EFI_HOB_MEMORY_ALLOCATION  *Hob;
 638
 639   ASSERT (((BaseAddress & (EFI_PAGE_SIZE - 1)) == 0) &&
 640           ((Length & (EFI_PAGE_SIZE - 1)) == 0));
 641
 642   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, sizeof (EFI_HOB_MEMORY_ALLOCATION));
 643
 644   ZeroMem (&(Hob->AllocDescriptor.Name), sizeof (EFI_GUID));
 645   Hob->AllocDescriptor.MemoryBaseAddress = BaseAddress;
 646   Hob->AllocDescriptor.MemoryLength      = Length;
 647   Hob->AllocDescriptor.MemoryType        = MemoryType;
 648   //
 649   // Zero the reserved space to match HOB spec
 650   //
 651   ZeroMem (Hob->AllocDescriptor.Reserved, sizeof (Hob->AllocDescriptor.Reserved));
 652 }