[mirror_edk2.git] / MdeModulePkg / Core / Pei / Memory / MemoryServices.c

/** @file\r
  EFI PEI Core memory services\r
  \r
Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
This program and the accompanying materials                          \r
are licensed and made available under the terms and conditions of the BSD License         \r
which accompanies this distribution.  The full text of the license may be found at        \r
http://opensource.org/licenses/bsd-license.php                                            \r
                                                                                          \r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     \r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             \r
\r
**/\r
\r
#include "PeiMain.h"\r
\r
/**\r
\r
  Initialize the memory services.\r
\r
  @param PrivateData     Points to PeiCore's private instance data.\r
  @param SecCoreData     Points to a data structure containing information about the PEI core's operating\r
                         environment, such as the size and location of temporary RAM, the stack location and\r
                         the BFV location.\r
  @param OldCoreData     Pointer to the PEI Core data.\r
                         NULL if being run in non-permament memory mode.\r
\r
**/\r
VOID\r
InitializeMemoryServices (\r
  IN PEI_CORE_INSTANCE           *PrivateData,\r
  IN CONST EFI_SEC_PEI_HAND_OFF  *SecCoreData,\r
  IN PEI_CORE_INSTANCE           *OldCoreData\r
  )\r
{\r
  \r
  PrivateData->SwitchStackSignal    = FALSE;\r
\r
  //\r
  // First entering PeiCore, following code will initialized some field\r
  // in PeiCore's private data according to hand off data from sec core.\r
  //\r
  if (OldCoreData == NULL) {\r
\r
    PrivateData->PeiMemoryInstalled = FALSE;\r
    PrivateData->HobList.Raw        = SecCoreData->PeiTemporaryRamBase;\r
    \r
    PeiCoreBuildHobHandoffInfoTable (\r
      BOOT_WITH_FULL_CONFIGURATION,\r
      (EFI_PHYSICAL_ADDRESS) (UINTN) SecCoreData->PeiTemporaryRamBase,\r
      (UINTN) SecCoreData->PeiTemporaryRamSize\r
      );\r
\r
    //\r
    // Set Ps to point to ServiceTableShadow in Cache\r
    //\r
    PrivateData->Ps = &(PrivateData->ServiceTableShadow);\r
  }\r
  \r
  return;\r
}\r
\r
/**\r
\r
  This function registers the found memory configuration with the PEI Foundation.\r
\r
  The usage model is that the PEIM that discovers the permanent memory shall invoke this service.\r
  This routine will hold discoveried memory information into PeiCore's private data,\r
  and set SwitchStackSignal flag. After PEIM who discovery memory is dispatched,\r
  PeiDispatcher will migrate temporary memory to permenement memory.\r
  \r
  @param PeiServices        An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
  @param MemoryBegin        Start of memory address.\r
  @param MemoryLength       Length of memory.\r
\r
  @return EFI_SUCCESS Always success.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
PeiInstallPeiMemory (\r
  IN CONST EFI_PEI_SERVICES  **PeiServices,\r
  IN EFI_PHYSICAL_ADDRESS    MemoryBegin,\r
  IN UINT64                  MemoryLength\r
  )\r
{\r
  PEI_CORE_INSTANCE                     *PrivateData;\r
\r
  DEBUG ((EFI_D_INFO, "PeiInstallPeiMemory MemoryBegin 0x%LX, MemoryLength 0x%LX\n", MemoryBegin, MemoryLength));\r
  PrivateData = PEI_CORE_INSTANCE_FROM_PS_THIS (PeiServices);\r
\r
  //\r
  // PEI_SERVICE.InstallPeiMemory should only be called one time during whole PEI phase.\r
  // If it is invoked more than one time, ASSERT information is given for developer debugging in debug tip and\r
  // simply return EFI_SUCESS in release tip to ignore it.\r
  // \r
  if (PrivateData->PeiMemoryInstalled) {\r
    DEBUG ((EFI_D_ERROR, "ERROR: PeiInstallPeiMemory is called more than once!\n"));\r
    ASSERT (PrivateData->PeiMemoryInstalled);\r
    return EFI_SUCCESS;\r
  }\r
  \r
  PrivateData->PhysicalMemoryBegin   = MemoryBegin;\r
  PrivateData->PhysicalMemoryLength  = MemoryLength;\r
  PrivateData->FreePhysicalMemoryTop = MemoryBegin + MemoryLength;\r
   \r
  PrivateData->SwitchStackSignal      = TRUE;\r
\r
  return EFI_SUCCESS;   \r
}\r
\r
/**\r
  The purpose of the service is to publish an interface that allows \r
  PEIMs to allocate memory ranges that are managed by the PEI Foundation.\r
\r
  @param  PeiServices      An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
  @param  MemoryType       The type of memory to allocate.\r
  @param  Pages            The number of contiguous 4 KB pages to allocate.\r
  @param  Memory           Pointer to a physical address. On output, the address is set to the base \r
                           of the page range that was allocated.\r
\r
  @retval EFI_SUCCESS           The memory range was successfully allocated.\r
  @retval EFI_OUT_OF_RESOURCES  The pages could not be allocated.\r
  @retval EFI_INVALID_PARAMETER Type is not equal to EfiLoaderCode, EfiLoaderData, EfiRuntimeServicesCode, \r
                                EfiRuntimeServicesData, EfiBootServicesCode, EfiBootServicesData,\r
                                EfiACPIReclaimMemory, EfiReservedMemoryType, or EfiACPIMemoryNVS.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
PeiAllocatePages (\r
  IN CONST EFI_PEI_SERVICES     **PeiServices,\r
  IN       EFI_MEMORY_TYPE      MemoryType,\r
  IN       UINTN                Pages,\r
  OUT      EFI_PHYSICAL_ADDRESS *Memory\r
  )\r
{\r
  PEI_CORE_INSTANCE                       *PrivateData;\r
  EFI_PEI_HOB_POINTERS                    Hob;\r
  EFI_PHYSICAL_ADDRESS                    *FreeMemoryTop;\r
  EFI_PHYSICAL_ADDRESS                    *FreeMemoryBottom;\r
  UINTN                                   RemainingPages;\r
\r
  if ((MemoryType != EfiLoaderCode) &&\r
      (MemoryType != EfiLoaderData) &&\r
      (MemoryType != EfiRuntimeServicesCode) &&\r
      (MemoryType != EfiRuntimeServicesData) &&\r
      (MemoryType != EfiBootServicesCode) &&\r
      (MemoryType != EfiBootServicesData) &&\r
      (MemoryType != EfiACPIReclaimMemory) &&\r
      (MemoryType != EfiReservedMemoryType) &&\r
      (MemoryType != EfiACPIMemoryNVS)) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  PrivateData = PEI_CORE_INSTANCE_FROM_PS_THIS (PeiServices);\r
  Hob.Raw     = PrivateData->HobList.Raw;\r
  \r
  //\r
  // Check if Hob already available\r
  //\r
  if (!PrivateData->PeiMemoryInstalled) {\r
    //\r
    // When PeiInstallMemory is called but temporary memory has *not* been moved to temporary memory,\r
    // the AllocatePage will depend on the field of PEI_CORE_INSTANCE structure.\r
    //\r
    if (!PrivateData->SwitchStackSignal) {\r
      return EFI_NOT_AVAILABLE_YET;\r
    } else {\r
      FreeMemoryTop     = &(PrivateData->FreePhysicalMemoryTop);\r
      FreeMemoryBottom  = &(PrivateData->PhysicalMemoryBegin);\r
    }\r
  } else {\r
    FreeMemoryTop     = &(Hob.HandoffInformationTable->EfiFreeMemoryTop);\r
    FreeMemoryBottom  = &(Hob.HandoffInformationTable->EfiFreeMemoryBottom);\r
  }\r
\r
  //\r
  // Check to see if on 4k boundary, If not aligned, make the allocation aligned.\r
  //\r
  *(FreeMemoryTop) -= *(FreeMemoryTop) & 0xFFF;\r
\r
  //\r
  // Verify that there is sufficient memory to satisfy the allocation.\r
  // For page allocation, the overhead sizeof (EFI_HOB_MEMORY_ALLOCATION) needs to be considered.\r
  //\r
  if ((UINTN) (*FreeMemoryTop - *FreeMemoryBottom) < (UINTN) ALIGN_VALUE (sizeof (EFI_HOB_MEMORY_ALLOCATION), 8)) {\r
    DEBUG ((EFI_D_ERROR, "AllocatePages failed: No space to build memory allocation hob.\n"));\r
    return  EFI_OUT_OF_RESOURCES;\r
  }\r
  RemainingPages = (UINTN)(*FreeMemoryTop - *FreeMemoryBottom - ALIGN_VALUE (sizeof (EFI_HOB_MEMORY_ALLOCATION), 8)) >> EFI_PAGE_SHIFT;\r
  //\r
  // The number of remaining pages needs to be greater than or equal to that of the request pages.\r
  //\r
  if (RemainingPages < Pages) {\r
    DEBUG ((EFI_D_ERROR, "AllocatePages failed: No 0x%lx Pages is available.\n", (UINT64) Pages));\r
    DEBUG ((EFI_D_ERROR, "There is only left 0x%lx pages memory resource to be allocated.\n", (UINT64) RemainingPages));\r
    return  EFI_OUT_OF_RESOURCES;\r
  } else {\r
    //\r
    // Update the PHIT to reflect the memory usage\r
    //\r
    *(FreeMemoryTop) -= Pages * EFI_PAGE_SIZE;\r
\r
    //\r
    // Update the value for the caller\r
    //\r
    *Memory = *(FreeMemoryTop);\r
\r
    //\r
    // Create a memory allocation HOB.\r
    //\r
    BuildMemoryAllocationHob (\r
      *(FreeMemoryTop),\r
      Pages * EFI_PAGE_SIZE,\r
      MemoryType\r
      );\r
\r
    return EFI_SUCCESS;\r
  }\r
}\r
\r
/**\r
\r
  Pool allocation service. Before permenent memory is discoveried, the pool will \r
  be allocated the heap in the temporary memory. Genenrally, the size of heap in temporary \r
  memory does not exceed to 64K, so the biggest pool size could be allocated is \r
  64K.\r
\r
  @param PeiServices               An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
  @param Size                      Amount of memory required\r
  @param Buffer                    Address of pointer to the buffer\r
\r
  @retval EFI_SUCCESS              The allocation was successful\r
  @retval EFI_OUT_OF_RESOURCES     There is not enough heap to satisfy the requirement\r
                                   to allocate the requested size.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
PeiAllocatePool (\r
  IN CONST EFI_PEI_SERVICES     **PeiServices,\r
  IN       UINTN                Size,\r
  OUT      VOID                 **Buffer\r
  )\r
{\r
  EFI_STATUS               Status;\r
  EFI_HOB_MEMORY_POOL      *Hob;\r
\r
  //\r
  // If some "post-memory" PEIM wishes to allocate larger pool,\r
  // it should use AllocatePages service instead.\r
  //\r
  \r
  //\r
  // Generally, the size of heap in temporary memory does not exceed to 64K,\r
  // HobLength is multiples of 8 bytes, so the maxmium size of pool is 0xFFF8 - sizeof (EFI_HOB_MEMORY_POOL)\r
  //\r
  if (Size > (0xFFF8 - sizeof (EFI_HOB_MEMORY_POOL))) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
  \r
  Status = PeiServicesCreateHob (\r
             EFI_HOB_TYPE_MEMORY_POOL,\r
             (UINT16)(sizeof (EFI_HOB_MEMORY_POOL) + Size),\r
             (VOID **)&Hob\r
             );\r
  ASSERT_EFI_ERROR (Status);\r
  *Buffer = Hob+1;  \r
\r
  return Status;\r
}\r
Commit	Line	Data
	1	/** @file\r
	2	EFI PEI Core memory services\r
	3	\r
	4	Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
	5	This program and the accompanying materials \r
	6	are licensed and made available under the terms and conditions of the BSD License \r
	7	which accompanies this distribution. The full text of the license may be found at \r
	8	http://opensource.org/licenses/bsd-license.php \r
	9	\r
	10	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
	11	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
	12	\r
	13	**/\r
	14	\r
	15	#include "PeiMain.h"\r
	16	\r
	17	/**\r
	18	\r
	19	Initialize the memory services.\r
	20	\r
	21	@param PrivateData Points to PeiCore's private instance data.\r
	22	@param SecCoreData Points to a data structure containing information about the PEI core's operating\r
	23	environment, such as the size and location of temporary RAM, the stack location and\r
	24	the BFV location.\r
	25	@param OldCoreData Pointer to the PEI Core data.\r
	26	NULL if being run in non-permament memory mode.\r
	27	\r
	28	**/\r
	29	VOID\r
	30	InitializeMemoryServices (\r
	31	IN PEI_CORE_INSTANCE *PrivateData,\r
	32	IN CONST EFI_SEC_PEI_HAND_OFF *SecCoreData,\r
	33	IN PEI_CORE_INSTANCE *OldCoreData\r
	34	)\r
	35	{\r
	36	\r
	37	PrivateData->SwitchStackSignal = FALSE;\r
	38	\r
	39	//\r
	40	// First entering PeiCore, following code will initialized some field\r
	41	// in PeiCore's private data according to hand off data from sec core.\r
	42	//\r
	43	if (OldCoreData == NULL) {\r
	44	\r
	45	PrivateData->PeiMemoryInstalled = FALSE;\r
	46	PrivateData->HobList.Raw = SecCoreData->PeiTemporaryRamBase;\r
	47	\r
	48	PeiCoreBuildHobHandoffInfoTable (\r
	49	BOOT_WITH_FULL_CONFIGURATION,\r
	50	(EFI_PHYSICAL_ADDRESS) (UINTN) SecCoreData->PeiTemporaryRamBase,\r
	51	(UINTN) SecCoreData->PeiTemporaryRamSize\r
	52	);\r
	53	\r
	54	//\r
	55	// Set Ps to point to ServiceTableShadow in Cache\r
	56	//\r
	57	PrivateData->Ps = &(PrivateData->ServiceTableShadow);\r
	58	}\r
	59	\r
	60	return;\r
	61	}\r
	62	\r
	63	/**\r
	64	\r
	65	This function registers the found memory configuration with the PEI Foundation.\r
	66	\r
	67	The usage model is that the PEIM that discovers the permanent memory shall invoke this service.\r
	68	This routine will hold discoveried memory information into PeiCore's private data,\r
	69	and set SwitchStackSignal flag. After PEIM who discovery memory is dispatched,\r
	70	PeiDispatcher will migrate temporary memory to permenement memory.\r
	71	\r
	72	@param PeiServices An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
	73	@param MemoryBegin Start of memory address.\r
	74	@param MemoryLength Length of memory.\r
	75	\r
	76	@return EFI_SUCCESS Always success.\r
	77	\r
	78	**/\r
	79	EFI_STATUS\r
	80	EFIAPI\r
	81	PeiInstallPeiMemory (\r
	82	IN CONST EFI_PEI_SERVICES **PeiServices,\r
	83	IN EFI_PHYSICAL_ADDRESS MemoryBegin,\r
	84	IN UINT64 MemoryLength\r
	85	)\r
	86	{\r
	87	PEI_CORE_INSTANCE *PrivateData;\r
	88	\r
	89	DEBUG ((EFI_D_INFO, "PeiInstallPeiMemory MemoryBegin 0x%LX, MemoryLength 0x%LX\n", MemoryBegin, MemoryLength));\r
	90	PrivateData = PEI_CORE_INSTANCE_FROM_PS_THIS (PeiServices);\r
	91	\r
	92	//\r
	93	// PEI_SERVICE.InstallPeiMemory should only be called one time during whole PEI phase.\r
	94	// If it is invoked more than one time, ASSERT information is given for developer debugging in debug tip and\r
	95	// simply return EFI_SUCESS in release tip to ignore it.\r
	96	// \r
	97	if (PrivateData->PeiMemoryInstalled) {\r
	98	DEBUG ((EFI_D_ERROR, "ERROR: PeiInstallPeiMemory is called more than once!\n"));\r
	99	ASSERT (PrivateData->PeiMemoryInstalled);\r
	100	return EFI_SUCCESS;\r
	101	}\r
	102	\r
	103	PrivateData->PhysicalMemoryBegin = MemoryBegin;\r
	104	PrivateData->PhysicalMemoryLength = MemoryLength;\r
	105	PrivateData->FreePhysicalMemoryTop = MemoryBegin + MemoryLength;\r
	106	\r
	107	PrivateData->SwitchStackSignal = TRUE;\r
	108	\r
	109	return EFI_SUCCESS; \r
	110	}\r
	111	\r
	112	/**\r
	113	The purpose of the service is to publish an interface that allows \r
	114	PEIMs to allocate memory ranges that are managed by the PEI Foundation.\r
	115	\r
	116	@param PeiServices An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
	117	@param MemoryType The type of memory to allocate.\r
	118	@param Pages The number of contiguous 4 KB pages to allocate.\r
	119	@param Memory Pointer to a physical address. On output, the address is set to the base \r
	120	of the page range that was allocated.\r
	121	\r
	122	@retval EFI_SUCCESS The memory range was successfully allocated.\r
	123	@retval EFI_OUT_OF_RESOURCES The pages could not be allocated.\r
	124	@retval EFI_INVALID_PARAMETER Type is not equal to EfiLoaderCode, EfiLoaderData, EfiRuntimeServicesCode, \r
	125	EfiRuntimeServicesData, EfiBootServicesCode, EfiBootServicesData,\r
	126	EfiACPIReclaimMemory, EfiReservedMemoryType, or EfiACPIMemoryNVS.\r
	127	\r
	128	**/\r
	129	EFI_STATUS\r
	130	EFIAPI\r
	131	PeiAllocatePages (\r
	132	IN CONST EFI_PEI_SERVICES **PeiServices,\r
	133	IN EFI_MEMORY_TYPE MemoryType,\r
	134	IN UINTN Pages,\r
	135	OUT EFI_PHYSICAL_ADDRESS *Memory\r
	136	)\r
	137	{\r
	138	PEI_CORE_INSTANCE *PrivateData;\r
	139	EFI_PEI_HOB_POINTERS Hob;\r
	140	EFI_PHYSICAL_ADDRESS *FreeMemoryTop;\r
	141	EFI_PHYSICAL_ADDRESS *FreeMemoryBottom;\r
	142	UINTN RemainingPages;\r
	143	\r
	144	if ((MemoryType != EfiLoaderCode) &&\r
	145	(MemoryType != EfiLoaderData) &&\r
	146	(MemoryType != EfiRuntimeServicesCode) &&\r
	147	(MemoryType != EfiRuntimeServicesData) &&\r
	148	(MemoryType != EfiBootServicesCode) &&\r
	149	(MemoryType != EfiBootServicesData) &&\r
	150	(MemoryType != EfiACPIReclaimMemory) &&\r
	151	(MemoryType != EfiReservedMemoryType) &&\r
	152	(MemoryType != EfiACPIMemoryNVS)) {\r
	153	return EFI_INVALID_PARAMETER;\r
	154	}\r
	155	\r
	156	PrivateData = PEI_CORE_INSTANCE_FROM_PS_THIS (PeiServices);\r
	157	Hob.Raw = PrivateData->HobList.Raw;\r
	158	\r
	159	//\r
	160	// Check if Hob already available\r
	161	//\r
	162	if (!PrivateData->PeiMemoryInstalled) {\r
	163	//\r
	164	// When PeiInstallMemory is called but temporary memory has not been moved to temporary memory,\r
	165	// the AllocatePage will depend on the field of PEI_CORE_INSTANCE structure.\r
	166	//\r
	167	if (!PrivateData->SwitchStackSignal) {\r
	168	return EFI_NOT_AVAILABLE_YET;\r
	169	} else {\r
	170	FreeMemoryTop = &(PrivateData->FreePhysicalMemoryTop);\r
	171	FreeMemoryBottom = &(PrivateData->PhysicalMemoryBegin);\r
	172	}\r
	173	} else {\r
	174	FreeMemoryTop = &(Hob.HandoffInformationTable->EfiFreeMemoryTop);\r
	175	FreeMemoryBottom = &(Hob.HandoffInformationTable->EfiFreeMemoryBottom);\r
	176	}\r
	177	\r
	178	//\r
	179	// Check to see if on 4k boundary, If not aligned, make the allocation aligned.\r
	180	//\r
	181	(FreeMemoryTop) -= (FreeMemoryTop) & 0xFFF;\r
	182	\r
	183	//\r
	184	// Verify that there is sufficient memory to satisfy the allocation.\r
	185	// For page allocation, the overhead sizeof (EFI_HOB_MEMORY_ALLOCATION) needs to be considered.\r
	186	//\r
	187	if ((UINTN) (FreeMemoryTop - FreeMemoryBottom) < (UINTN) ALIGN_VALUE (sizeof (EFI_HOB_MEMORY_ALLOCATION), 8)) {\r
	188	DEBUG ((EFI_D_ERROR, "AllocatePages failed: No space to build memory allocation hob.\n"));\r
	189	return EFI_OUT_OF_RESOURCES;\r
	190	}\r
	191	RemainingPages = (UINTN)(FreeMemoryTop - FreeMemoryBottom - ALIGN_VALUE (sizeof (EFI_HOB_MEMORY_ALLOCATION), 8)) >> EFI_PAGE_SHIFT;\r
	192	//\r
	193	// The number of remaining pages needs to be greater than or equal to that of the request pages.\r
	194	//\r
	195	if (RemainingPages < Pages) {\r
	196	DEBUG ((EFI_D_ERROR, "AllocatePages failed: No 0x%lx Pages is available.\n", (UINT64) Pages));\r
	197	DEBUG ((EFI_D_ERROR, "There is only left 0x%lx pages memory resource to be allocated.\n", (UINT64) RemainingPages));\r
	198	return EFI_OUT_OF_RESOURCES;\r
	199	} else {\r
	200	//\r
	201	// Update the PHIT to reflect the memory usage\r
	202	//\r
	203	(FreeMemoryTop) -= Pages EFI_PAGE_SIZE;\r
	204	\r
	205	//\r
	206	// Update the value for the caller\r
	207	//\r
	208	Memory = (FreeMemoryTop);\r
	209	\r
	210	//\r
	211	// Create a memory allocation HOB.\r
	212	//\r
	213	BuildMemoryAllocationHob (\r
	214	*(FreeMemoryTop),\r
	215	Pages * EFI_PAGE_SIZE,\r
	216	MemoryType\r
	217	);\r
	218	\r
	219	return EFI_SUCCESS;\r
	220	}\r
	221	}\r
	222	\r
	223	/**\r
	224	\r
	225	Pool allocation service. Before permenent memory is discoveried, the pool will \r
	226	be allocated the heap in the temporary memory. Genenrally, the size of heap in temporary \r
	227	memory does not exceed to 64K, so the biggest pool size could be allocated is \r
	228	64K.\r
	229	\r
	230	@param PeiServices An indirect pointer to the EFI_PEI_SERVICES table published by the PEI Foundation.\r
	231	@param Size Amount of memory required\r
	232	@param Buffer Address of pointer to the buffer\r
	233	\r
	234	@retval EFI_SUCCESS The allocation was successful\r
	235	@retval EFI_OUT_OF_RESOURCES There is not enough heap to satisfy the requirement\r
	236	to allocate the requested size.\r
	237	\r
	238	**/\r
	239	EFI_STATUS\r
	240	EFIAPI\r
	241	PeiAllocatePool (\r
	242	IN CONST EFI_PEI_SERVICES **PeiServices,\r
	243	IN UINTN Size,\r
	244	OUT VOID **Buffer\r
	245	)\r
	246	{\r
	247	EFI_STATUS Status;\r
	248	EFI_HOB_MEMORY_POOL *Hob;\r
	249	\r
	250	//\r
	251	// If some "post-memory" PEIM wishes to allocate larger pool,\r
	252	// it should use AllocatePages service instead.\r
	253	//\r
	254	\r
	255	//\r
	256	// Generally, the size of heap in temporary memory does not exceed to 64K,\r
	257	// HobLength is multiples of 8 bytes, so the maxmium size of pool is 0xFFF8 - sizeof (EFI_HOB_MEMORY_POOL)\r
	258	//\r
	259	if (Size > (0xFFF8 - sizeof (EFI_HOB_MEMORY_POOL))) {\r
	260	return EFI_OUT_OF_RESOURCES;\r
	261	}\r
	262	\r
	263	Status = PeiServicesCreateHob (\r
	264	EFI_HOB_TYPE_MEMORY_POOL,\r
	265	(UINT16)(sizeof (EFI_HOB_MEMORY_POOL) + Size),\r
	266	(VOID **)&Hob\r
	267	);\r
	268	ASSERT_EFI_ERROR (Status);\r
	269	*Buffer = Hob+1; \r
	270	\r
	271	return Status;\r
	272	}\r