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. All rights reserved.<BR>
   9 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 <FrameworkPei.h>
  20
  21 #include <Guid/MemoryAllocationHob.h>
  22
  23 #include <Library/HobLib.h>
  24 #include <Library/DebugLib.h>
  25 #include <Library/PeiServicesLib.h>
  26 #include <Library/BaseMemoryLib.h>
  27
  28 /**
  29   Returns the pointer to the HOB list.
  30
  31   This function returns the pointer to first HOB in the list.
  32   For PEI phase, the PEI service GetHobList() can be used to retrieve the pointer
  33   to the HOB list.  For the DXE phase, the HOB list pointer can be retrieved through
  34   the EFI System Table by looking up theHOB list GUID in the System Configuration Table.
  35   Since the System Configuration Table does not exist that the time the DXE Core is
  36   launched, the DXE Core uses a global variable from the DXE Core Entry Point Library
  37   to manage the pointer to the HOB list.
  38
  39   If the pointer to the HOB list is NULL, then ASSERT().
  40
  41   @return The pointer to the HOB list.
  42
  43 **/
  44 VOID *
  45 EFIAPI
  46 GetHobList (
  47   VOID
  48   )
  49 {
  50   EFI_STATUS            Status;
  51   VOID                  *HobList;
  52
  53   Status = PeiServicesGetHobList (&HobList);
  54   ASSERT_EFI_ERROR (Status);
  55   ASSERT (HobList != NULL);
  56
  57   return HobList;
  58 }
  59
  60 /**
  61   Returns the next instance of a HOB type from the starting HOB.
  62
  63   This function searches the first instance of a HOB type from the starting HOB pointer.
  64   If there does not exist such HOB type from the starting HOB pointer, it will return NULL.
  65   In contrast with macro GET_NEXT_HOB(), this function does not skip the starting HOB pointer
  66   unconditionally: it returns HobStart back if HobStart itself meets the requirement;
  67   caller is required to use GET_NEXT_HOB() if it wishes to skip current HobStart.
  68
  69   If HobStart is NULL, then ASSERT().
  70
  71   @param  Type          The HOB type to return.
  72   @param  HobStart      The starting HOB pointer to search from.
  73
  74   @return The next instance of a HOB type from the starting HOB.
  75
  76 **/
  77 VOID *
  78 EFIAPI
  79 GetNextHob (
  80   IN UINT16                 Type,
  81   IN CONST VOID             *HobStart
  82   )
  83 {
  84   EFI_PEI_HOB_POINTERS  Hob;
  85
  86   ASSERT (HobStart != NULL);
  87
  88   Hob.Raw = (UINT8 *) HobStart;
  89   //
  90   // Parse the HOB list until end of list or matching type is found.
  91   //
  92   while (!END_OF_HOB_LIST (Hob)) {
  93     if (Hob.Header->HobType == Type) {
  94       return Hob.Raw;
  95     }
  96     Hob.Raw = GET_NEXT_HOB (Hob);
  97   }
  98   return NULL;
  99 }
 100
 101 /**
 102   Returns the first instance of a HOB type among the whole HOB list.
 103
 104   This function searches the first instance of a HOB type among the whole HOB list.
 105   If there does not exist such HOB type in the HOB list, it will return NULL.
 106
 107   If the pointer to the HOB list is NULL, then ASSERT().
 108
 109   @param  Type          The HOB type to return.
 110
 111   @return The next instance of a HOB type from the starting HOB.
 112
 113 **/
 114 VOID *
 115 EFIAPI
 116 GetFirstHob (
 117   IN UINT16                 Type
 118   )
 119 {
 120   VOID      *HobList;
 121
 122   HobList = GetHobList ();
 123   return GetNextHob (Type, HobList);
 124 }
 125
 126 /**
 127   Returns the next instance of the matched GUID HOB from the starting HOB.
 128
 129   This function searches the first instance of a HOB from the starting HOB pointer.
 130   Such HOB should satisfy two conditions:
 131   its HOB type is EFI_HOB_TYPE_GUID_EXTENSION and its GUID Name equals to the input Guid.
 132   If there does not exist such HOB from the starting HOB pointer, it will return NULL.
 133   Caller is required to apply GET_GUID_HOB_DATA () and GET_GUID_HOB_DATA_SIZE ()
 134   to extract the data section and its size info respectively.
 135   In contrast with macro GET_NEXT_HOB(), this function does not skip the starting HOB pointer
 136   unconditionally: it returns HobStart back if HobStart itself meets the requirement;
 137   caller is required to use GET_NEXT_HOB() if it wishes to skip current HobStart.
 138
 139   If Guid is NULL, then ASSERT().
 140   If HobStart is NULL, then ASSERT().
 141
 142   @param  Guid          The GUID to match with in the HOB list.
 143   @param  HobStart      A pointer to a Guid.
 144
 145   @return The next instance of the matched GUID HOB from the starting HOB.
 146
 147 **/
 148 VOID *
 149 EFIAPI
 150 GetNextGuidHob (
 151   IN CONST EFI_GUID         *Guid,
 152   IN CONST VOID             *HobStart
 153   )
 154 {
 155   EFI_PEI_HOB_POINTERS  GuidHob;
 156
 157   GuidHob.Raw = (UINT8 *) HobStart;
 158   while ((GuidHob.Raw = GetNextHob (EFI_HOB_TYPE_GUID_EXTENSION, GuidHob.Raw)) != NULL) {
 159     if (CompareGuid (Guid, &GuidHob.Guid->Name)) {
 160       break;
 161     }
 162     GuidHob.Raw = GET_NEXT_HOB (GuidHob);
 163   }
 164   return GuidHob.Raw;
 165 }
 166
 167 /**
 168   Returns the first instance of the matched GUID HOB among the whole HOB list.
 169
 170   This function searches the first instance of a HOB among the whole HOB list.
 171   Such HOB should satisfy two conditions:
 172   its HOB type is EFI_HOB_TYPE_GUID_EXTENSION and its GUID Name equals to the input Guid.
 173   If there does not exist such HOB from the starting HOB pointer, it will return NULL.
 174   Caller is required to apply GET_GUID_HOB_DATA () and GET_GUID_HOB_DATA_SIZE ()
 175   to extract the data section and its size info respectively.
 176
 177   If the pointer to the HOB list is NULL, then ASSERT().
 178   If Guid is NULL, then ASSERT().
 179
 180   @param  Guid          The GUID to match with in the HOB list.
 181
 182   @return The first instance of the matched GUID HOB among the whole HOB list.
 183
 184 **/
 185 VOID *
 186 EFIAPI
 187 GetFirstGuidHob (
 188   IN CONST EFI_GUID         *Guid
 189   )
 190 {
 191   VOID      *HobList;
 192
 193   HobList = GetHobList ();
 194   return GetNextGuidHob (Guid, HobList);
 195 }
 196
 197 /**
 198   Get the system boot mode from the HOB list.
 199
 200   This function returns the system boot mode information from the
 201   PHIT HOB in HOB list.
 202
 203   If the pointer to the HOB list is NULL, then ASSERT().
 204
 205   @param  VOID
 206
 207   @return The Boot Mode.
 208
 209 **/
 210 EFI_BOOT_MODE
 211 EFIAPI
 212 GetBootModeHob (
 213   VOID
 214   )
 215 {
 216   EFI_STATUS             Status;
 217   EFI_BOOT_MODE          BootMode;
 218
 219   Status = PeiServicesGetBootMode (&BootMode);
 220   ASSERT_EFI_ERROR (Status);
 221
 222   return BootMode;
 223 }
 224
 225 /**
 226   Adds a new HOB to the HOB List.
 227
 228   This internal function enables PEIMs to create various types of HOBs.
 229
 230   @param  Type          Type of the new HOB.
 231   @param  Length        Length of the new HOB to allocate.
 232
 233   @return The address of new HOB.
 234
 235 **/
 236 VOID *
 237 EFIAPI
 238 InternalPeiCreateHob (
 239   IN UINT16                      Type,
 240   IN UINT16                      Length
 241   )
 242 {
 243   EFI_STATUS        Status;
 244   VOID              *Hob;
 245
 246   Status = PeiServicesCreateHob (Type, Length, &Hob);
 247   //
 248   // Assume the process of HOB building is always successful.
 249   //
 250   ASSERT_EFI_ERROR (Status);
 251   return Hob;
 252 }
 253
 254 /**
 255   Builds a HOB for a loaded PE32 module.
 256
 257   This function builds a HOB for a loaded PE32 module.
 258   It can only be invoked during PEI phase;
 259   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 260
 261   If ModuleName is NULL, then ASSERT().
 262   If there is no additional space for HOB creation, then ASSERT().
 263
 264   @param  ModuleName              The GUID File Name of the module.
 265   @param  MemoryAllocationModule  The 64 bit physical address of the module.
 266   @param  ModuleLength            The length of the module in bytes.
 267   @param  EntryPoint              The 64 bit physical address of the module entry point.
 268
 269 **/
 270 VOID
 271 EFIAPI
 272 BuildModuleHob (
 273   IN CONST EFI_GUID         *ModuleName,
 274   IN EFI_PHYSICAL_ADDRESS   MemoryAllocationModule,
 275   IN UINT64                 ModuleLength,
 276   IN EFI_PHYSICAL_ADDRESS   EntryPoint
 277   )
 278 {
 279   EFI_HOB_MEMORY_ALLOCATION_MODULE  *Hob;
 280
 281   ASSERT (((MemoryAllocationModule & (EFI_PAGE_SIZE - 1)) == 0) &&
 282           ((ModuleLength & (EFI_PAGE_SIZE - 1)) == 0));
 283
 284   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_MEMORY_ALLOCATION, sizeof (EFI_HOB_MEMORY_ALLOCATION_MODULE));
 285
 286   CopyGuid (&(Hob->MemoryAllocationHeader.Name), &gEfiHobMemoryAllocModuleGuid);
 287   Hob->MemoryAllocationHeader.MemoryBaseAddress = MemoryAllocationModule;
 288   Hob->MemoryAllocationHeader.MemoryLength      = ModuleLength;
 289   Hob->MemoryAllocationHeader.MemoryType        = EfiBootServicesCode;
 290
 291   //
 292   // Zero the reserved space to match HOB spec
 293   //
 294   ZeroMem (Hob->MemoryAllocationHeader.Reserved, sizeof (Hob->MemoryAllocationHeader.Reserved));
 295
 296   CopyGuid (&Hob->ModuleName, ModuleName);
 297   Hob->EntryPoint = EntryPoint;
 298 }
 299
 300 /**
 301   Builds a HOB that describes a chunk of system memory.
 302
 303   This function builds a HOB that describes a chunk of system memory.
 304   It can only be invoked during PEI phase;
 305   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 306
 307   If there is no additional space for HOB creation, then ASSERT().
 308
 309   @param  ResourceType        The type of resource described by this HOB.
 310   @param  ResourceAttribute   The resource attributes of the memory described by this HOB.
 311   @param  PhysicalStart       The 64 bit physical address of memory described by this HOB.
 312   @param  NumberOfBytes       The length of the memory described by this HOB in bytes.
 313
 314 **/
 315 VOID
 316 EFIAPI
 317 BuildResourceDescriptorHob (
 318   IN EFI_RESOURCE_TYPE            ResourceType,
 319   IN EFI_RESOURCE_ATTRIBUTE_TYPE  ResourceAttribute,
 320   IN EFI_PHYSICAL_ADDRESS         PhysicalStart,
 321   IN UINT64                       NumberOfBytes
 322   )
 323 {
 324   EFI_HOB_RESOURCE_DESCRIPTOR  *Hob;
 325
 326   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_RESOURCE_DESCRIPTOR, sizeof (EFI_HOB_RESOURCE_DESCRIPTOR));
 327
 328   Hob->ResourceType      = ResourceType;
 329   Hob->ResourceAttribute = ResourceAttribute;
 330   Hob->PhysicalStart     = PhysicalStart;
 331   Hob->ResourceLength    = NumberOfBytes;
 332 }
 333
 334 /**
 335   Builds a customized HOB tagged with a GUID for identification and returns
 336   the start address of GUID HOB data.
 337
 338   This function builds a customized HOB tagged with a GUID for identification
 339   and returns the start address of GUID HOB data so that caller can fill the customized data.
 340   The HOB Header and Name field is already stripped.
 341   It can only be invoked during PEI phase;
 342   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 343
 344   If Guid is NULL, then ASSERT().
 345   If there is no additional space for HOB creation, then ASSERT().
 346   If DataLength >= (0x10000 - sizeof (EFI_HOB_GUID_TYPE)), then ASSERT().
 347
 348   @param  Guid          The GUID to tag the customized HOB.
 349   @param  DataLength    The size of the data payload for the GUID HOB.
 350
 351   @return The start address of GUID HOB data.
 352
 353 **/
 354 VOID *
 355 EFIAPI
 356 BuildGuidHob (
 357   IN CONST EFI_GUID              *Guid,
 358   IN UINTN                       DataLength
 359   )
 360 {
 361   EFI_HOB_GUID_TYPE *Hob;
 362
 363   //
 364   // Make sure that data length is not too long.
 365   //
 366   ASSERT (DataLength <= (0xffff - sizeof (EFI_HOB_GUID_TYPE)));
 367
 368   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_GUID_EXTENSION, (UINT16) (sizeof (EFI_HOB_GUID_TYPE) + DataLength));
 369   CopyGuid (&Hob->Name, Guid);
 370   return Hob + 1;
 371 }
 372
 373 /**
 374   Builds a customized HOB tagged with a GUID for identification, copies the input data to the HOB
 375   data field, and returns the start address of the GUID HOB data.
 376
 377   This function builds a customized HOB tagged with a GUID for identification and copies the input
 378   data to the HOB data field and returns the start address of the GUID HOB data.  It can only be
 379   invoked during PEI phase; for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 380   The HOB Header and Name field is already stripped.
 381   It can only be invoked during PEI phase;
 382   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 383
 384   If Guid is NULL, then ASSERT().
 385   If Data is NULL and DataLength > 0, then ASSERT().
 386   If there is no additional space for HOB creation, then ASSERT().
 387   If DataLength >= (0x10000 - sizeof (EFI_HOB_GUID_TYPE)), then ASSERT().
 388
 389   @param  Guid          The GUID to tag the customized HOB.
 390   @param  Data          The data to be copied into the data field of the GUID HOB.
 391   @param  DataLength    The size of the data payload for the GUID HOB.
 392
 393   @return The start address of GUID HOB data.
 394
 395 **/
 396 VOID *
 397 EFIAPI
 398 BuildGuidDataHob (
 399   IN CONST EFI_GUID              *Guid,
 400   IN VOID                        *Data,
 401   IN UINTN                       DataLength
 402   )
 403 {
 404   VOID  *HobData;
 405
 406   ASSERT (Data != NULL || DataLength == 0);
 407
 408   HobData = BuildGuidHob (Guid, DataLength);
 409
 410   return CopyMem (HobData, Data, DataLength);
 411 }
 412
 413 /**
 414   Builds a Firmware Volume HOB.
 415
 416   This function builds a Firmware Volume HOB.
 417   It can only be invoked during PEI phase;
 418   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 419
 420   If there is no additional space for HOB creation, then ASSERT().
 421
 422   @param  BaseAddress   The base address of the Firmware Volume.
 423   @param  Length        The size of the Firmware Volume in bytes.
 424
 425 **/
 426 VOID
 427 EFIAPI
 428 BuildFvHob (
 429   IN EFI_PHYSICAL_ADDRESS        BaseAddress,
 430   IN UINT64                      Length
 431   )
 432 {
 433   EFI_HOB_FIRMWARE_VOLUME  *Hob;
 434
 435   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_FV, sizeof (EFI_HOB_FIRMWARE_VOLUME));
 436
 437   Hob->BaseAddress = BaseAddress;
 438   Hob->Length      = Length;
 439 }
 440
 441 /**
 442   Builds a EFI_HOB_TYPE_FV2 HOB.
 443
 444   This function builds a EFI_HOB_TYPE_FV2 HOB.
 445   It can only be invoked during PEI phase;
 446   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 447
 448   If there is no additional space for HOB creation, then ASSERT().
 449
 450   @param  BaseAddress   The base address of the Firmware Volume.
 451   @param  Length        The size of the Firmware Volume in bytes.
 452   @param  FvName        The name of the Firmware Volume.
 453   @param  FileName      The name of the file.
 454
 455 **/
 456 VOID
 457 EFIAPI
 458 BuildFv2Hob (
 459   IN          EFI_PHYSICAL_ADDRESS        BaseAddress,
 460   IN          UINT64                      Length,
 461   IN CONST    EFI_GUID                    *FvName,
 462   IN CONST    EFI_GUID                    *FileName
 463   )
 464 {
 465   EFI_HOB_FIRMWARE_VOLUME2  *Hob;
 466
 467   Hob = InternalPeiCreateHob (EFI_HOB_TYPE_FV2, sizeof (EFI_HOB_FIRMWARE_VOLUME2));
 468
 469   Hob->BaseAddress = BaseAddress;
 470   Hob->Length      = Length;
 471   CopyGuid (&Hob->FvName, FvName);
 472   CopyGuid (&Hob->FileName, FileName);
 473 }
 474
 475 /**
 476   Builds a Capsule Volume HOB.
 477
 478   This function builds a Capsule Volume HOB.
 479   It can only be invoked during PEI phase;
 480   for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
 481
 482   If the platform does not support Capsule Volume HOBs, then ASSERT().
 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 }