[mirror_edk2.git] / MdePkg / Library / UefiLib / Acpi.c

/** @file\r
  This module provides help function for finding ACPI table.\r
\r
  Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>\r
  SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include "UefiLibInternal.h"\r
#include <IndustryStandard/Acpi.h>\r
#include <Guid/Acpi.h>\r
\r
/**\r
  This function scans ACPI table in XSDT/RSDT.\r
\r
  @param Sdt                    ACPI XSDT/RSDT.\r
  @param TablePointerSize       Size of table pointer: 8(XSDT) or 4(RSDT).\r
  @param Signature              ACPI table signature.\r
  @param PreviousTable          Pointer to previous returned table to locate\r
                                next table, or NULL to locate first table.\r
  @param PreviousTableLocated   Pointer to the indicator about whether the\r
                                previous returned table could be located, or\r
                                NULL if PreviousTable is NULL.\r
\r
  If PreviousTable is NULL and PreviousTableLocated is not NULL, then ASSERT().\r
  If PreviousTable is not NULL and PreviousTableLocated is NULL, then ASSERT().\r
\r
  @return ACPI table or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
ScanTableInSDT (\r
  IN  EFI_ACPI_DESCRIPTION_HEADER   *Sdt,\r
  IN  UINTN                         TablePointerSize,\r
  IN  UINT32                        Signature,\r
  IN  EFI_ACPI_COMMON_HEADER        *PreviousTable, OPTIONAL\r
  OUT BOOLEAN                       *PreviousTableLocated OPTIONAL\r
  )\r
{\r
  UINTN                             Index;\r
  UINTN                             EntryCount;\r
  UINT64                            EntryPtr;\r
  UINTN                             BasePtr;\r
  EFI_ACPI_COMMON_HEADER            *Table;\r
\r
  if (PreviousTableLocated != NULL) {\r
    ASSERT (PreviousTable != NULL);\r
    *PreviousTableLocated = FALSE;\r
  } else {\r
    ASSERT (PreviousTable == NULL);\r
  }\r
\r
  if (Sdt == NULL) {\r
    return NULL;\r
  }\r
\r
  EntryCount = (Sdt->Length - sizeof (EFI_ACPI_DESCRIPTION_HEADER)) / TablePointerSize;\r
\r
  BasePtr = (UINTN)(Sdt + 1);\r
  for (Index = 0; Index < EntryCount; Index ++) {\r
    EntryPtr = 0;\r
    CopyMem (&EntryPtr, (VOID *)(BasePtr + Index * TablePointerSize), TablePointerSize);\r
    Table = (EFI_ACPI_COMMON_HEADER *)((UINTN)(EntryPtr));\r
    if ((Table != NULL) && (Table->Signature == Signature)) {\r
      if (PreviousTable != NULL) {\r
        if (Table == PreviousTable) {\r
          *PreviousTableLocated = TRUE;\r
        } else if (*PreviousTableLocated) {\r
          //\r
          // Return next table.\r
          //\r
          return Table;\r
        }\r
      } else {\r
        //\r
        // Return first table.\r
        //\r
        return Table;\r
      }\r
\r
    }\r
  }\r
\r
  return NULL;\r
}\r
\r
/**\r
  To locate FACS in FADT.\r
\r
  @param Fadt   FADT table pointer.\r
\r
  @return FACS table pointer or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
LocateAcpiFacsFromFadt (\r
  IN EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE  *Fadt\r
  )\r
{\r
  EFI_ACPI_COMMON_HEADER                        *Facs;\r
  UINT64                                        Data64;\r
\r
  if (Fadt == NULL) {\r
    return NULL;\r
  }\r
\r
  if (Fadt->Header.Revision < EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_REVISION) {\r
    Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->FirmwareCtrl;\r
  } else {\r
    CopyMem (&Data64, &Fadt->XFirmwareCtrl, sizeof(UINT64));\r
    if (Data64 != 0) {\r
      Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Data64;\r
    } else {\r
      Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->FirmwareCtrl;\r
    }\r
  }\r
  return Facs;\r
}\r
\r
/**\r
  To locate DSDT in FADT.\r
\r
  @param Fadt   FADT table pointer.\r
\r
  @return DSDT table pointer or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
LocateAcpiDsdtFromFadt (\r
  IN EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE  *Fadt\r
  )\r
{\r
  EFI_ACPI_COMMON_HEADER                        *Dsdt;\r
  UINT64                                        Data64;\r
\r
  if (Fadt == NULL) {\r
    return NULL;\r
  }\r
\r
  if (Fadt->Header.Revision < EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_REVISION) {\r
    Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->Dsdt;\r
  } else {\r
    CopyMem (&Data64, &Fadt->XDsdt, sizeof(UINT64));\r
    if (Data64 != 0) {\r
      Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Data64;\r
    } else {\r
      Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->Dsdt;\r
    }\r
  }\r
  return Dsdt;\r
}\r
\r
/**\r
  To locate ACPI table in ACPI ConfigurationTable.\r
\r
  @param AcpiGuid               The GUID used to get ACPI ConfigurationTable.\r
  @param Signature              ACPI table signature.\r
  @param PreviousTable          Pointer to previous returned table to locate\r
                                next table, or NULL to locate first table.\r
  @param PreviousTableLocated   Pointer to the indicator to return whether the\r
                                previous returned table could be located or not,\r
                                or NULL if PreviousTable is NULL.\r
\r
  If PreviousTable is NULL and PreviousTableLocated is not NULL, then ASSERT().\r
  If PreviousTable is not NULL and PreviousTableLocated is NULL, then ASSERT().\r
  If AcpiGuid is NULL, then ASSERT().\r
\r
  @return ACPI table or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
LocateAcpiTableInAcpiConfigurationTable (\r
  IN  EFI_GUID                  *AcpiGuid,\r
  IN  UINT32                    Signature,\r
  IN  EFI_ACPI_COMMON_HEADER    *PreviousTable, OPTIONAL\r
  OUT BOOLEAN                   *PreviousTableLocated OPTIONAL\r
  )\r
{\r
  EFI_STATUS                                    Status;\r
  EFI_ACPI_COMMON_HEADER                        *Table;\r
  EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER  *Rsdp;\r
  EFI_ACPI_DESCRIPTION_HEADER                   *Rsdt;\r
  EFI_ACPI_DESCRIPTION_HEADER                   *Xsdt;\r
  EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE     *Fadt;\r
\r
  if (PreviousTableLocated != NULL) {\r
    ASSERT (PreviousTable != NULL);\r
    *PreviousTableLocated = FALSE;\r
  } else {\r
    ASSERT (PreviousTable == NULL);\r
  }\r
\r
  Rsdp = NULL;\r
  //\r
  // Get ACPI ConfigurationTable (RSD_PTR)\r
  //\r
  Status = EfiGetSystemConfigurationTable(AcpiGuid, (VOID **)&Rsdp);\r
  if (EFI_ERROR (Status) || (Rsdp == NULL)) {\r
    return NULL;\r
  }\r
\r
  Table = NULL;\r
\r
  //\r
  // Search XSDT\r
  //\r
  if (Rsdp->Revision >= EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER_REVISION) {\r
    Xsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->XsdtAddress;\r
    if (Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) {\r
      ASSERT (PreviousTable == NULL);\r
      //\r
      // It is to locate DSDT,\r
      // need to locate FADT first.\r
      //\r
      Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
               Xsdt,\r
               sizeof (UINT64),\r
               EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
               NULL,\r
               NULL\r
               );\r
      Table = LocateAcpiDsdtFromFadt (Fadt);\r
    } else if (Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) {\r
      ASSERT (PreviousTable == NULL);\r
      //\r
      // It is to locate FACS,\r
      // need to locate FADT first.\r
      //\r
      Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
               Xsdt,\r
               sizeof (UINT64),\r
               EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
               NULL,\r
               NULL\r
               );\r
      Table = LocateAcpiFacsFromFadt (Fadt);\r
    } else {\r
      Table = ScanTableInSDT (\r
                Xsdt,\r
                sizeof (UINT64),\r
                Signature,\r
                PreviousTable,\r
                PreviousTableLocated\r
                );\r
    }\r
  }\r
\r
  if (Table != NULL) {\r
    return Table;\r
  } else if ((PreviousTableLocated != NULL) &&\r
              *PreviousTableLocated) {\r
    //\r
    // PreviousTable could be located in XSDT,\r
    // but next table could not be located in XSDT.\r
    //\r
    return NULL;\r
  }\r
\r
  //\r
  // Search RSDT\r
  //\r
  Rsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->RsdtAddress;\r
  if (Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) {\r
    ASSERT (PreviousTable == NULL);\r
    //\r
    // It is to locate DSDT,\r
    // need to locate FADT first.\r
    //\r
    Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
             Rsdt,\r
             sizeof (UINT32),\r
             EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
             NULL,\r
             NULL\r
             );\r
    Table = LocateAcpiDsdtFromFadt (Fadt);\r
  } else if (Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) {\r
    ASSERT (PreviousTable == NULL);\r
    //\r
    // It is to locate FACS,\r
    // need to locate FADT first.\r
    //\r
    Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
             Rsdt,\r
             sizeof (UINT32),\r
             EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
             NULL,\r
             NULL\r
             );\r
    Table = LocateAcpiFacsFromFadt (Fadt);\r
  } else {\r
    Table = ScanTableInSDT (\r
              Rsdt,\r
              sizeof (UINT32),\r
              Signature,\r
              PreviousTable,\r
              PreviousTableLocated\r
              );\r
  }\r
\r
  return Table;\r
}\r
\r
/**\r
  This function locates next ACPI table in XSDT/RSDT based on Signature and\r
  previous returned Table.\r
\r
  If PreviousTable is NULL:\r
  This function will locate the first ACPI table in XSDT/RSDT based on\r
  Signature in gEfiAcpi20TableGuid system configuration table first, and then\r
  gEfiAcpi10TableGuid system configuration table.\r
  This function will locate in XSDT first, and then RSDT.\r
  For DSDT, this function will locate XDsdt in FADT first, and then Dsdt in\r
  FADT.\r
  For FACS, this function will locate XFirmwareCtrl in FADT first, and then\r
  FirmwareCtrl in FADT.\r
\r
  If PreviousTable is not NULL:\r
  1. If it could be located in XSDT in gEfiAcpi20TableGuid system configuration\r
     table, then this function will just locate next table in XSDT in\r
     gEfiAcpi20TableGuid system configuration table.\r
  2. If it could be located in RSDT in gEfiAcpi20TableGuid system configuration\r
     table, then this function will just locate next table in RSDT in\r
     gEfiAcpi20TableGuid system configuration table.\r
  3. If it could be located in RSDT in gEfiAcpi10TableGuid system configuration\r
     table, then this function will just locate next table in RSDT in\r
     gEfiAcpi10TableGuid system configuration table.\r
\r
  It's not supported that PreviousTable is not NULL but PreviousTable->Signature\r
  is not same with Signature, NULL will be returned.\r
\r
  @param Signature          ACPI table signature.\r
  @param PreviousTable      Pointer to previous returned table to locate next\r
                            table, or NULL to locate first table.\r
\r
  @return Next ACPI table or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
EFIAPI\r
EfiLocateNextAcpiTable (\r
  IN UINT32                     Signature,\r
  IN EFI_ACPI_COMMON_HEADER     *PreviousTable OPTIONAL\r
  )\r
{\r
  EFI_ACPI_COMMON_HEADER        *Table;\r
  BOOLEAN                       TempPreviousTableLocated;\r
  BOOLEAN                       *PreviousTableLocated;\r
\r
  if (PreviousTable != NULL) {\r
    if (PreviousTable->Signature != Signature) {\r
      //\r
      // PreviousTable->Signature is not same with Signature.\r
      //\r
      return NULL;\r
    } else if ((Signature == EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE) ||\r
               (Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) ||\r
               (Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE)) {\r
      //\r
      // There is only one FADT/DSDT/FACS table,\r
      // so don't try to locate next one.\r
      //\r
      return NULL;\r
    }\r
\r
    PreviousTableLocated = &TempPreviousTableLocated;\r
    *PreviousTableLocated = FALSE;\r
  } else {\r
    PreviousTableLocated = NULL;\r
  }\r
\r
  Table = LocateAcpiTableInAcpiConfigurationTable (\r
            &gEfiAcpi20TableGuid,\r
            Signature,\r
            PreviousTable,\r
            PreviousTableLocated\r
            );\r
  if (Table != NULL) {\r
    return Table;\r
  } else if ((PreviousTableLocated != NULL) &&\r
              *PreviousTableLocated) {\r
    //\r
    // PreviousTable could be located in gEfiAcpi20TableGuid system\r
    // configuration table, but next table could not be located in\r
    // gEfiAcpi20TableGuid system configuration table.\r
    //\r
    return NULL;\r
  }\r
\r
  return LocateAcpiTableInAcpiConfigurationTable (\r
           &gEfiAcpi10TableGuid,\r
           Signature,\r
           PreviousTable,\r
           PreviousTableLocated\r
           );\r
}\r
\r
/**\r
  This function locates first ACPI table in XSDT/RSDT based on Signature.\r
\r
  This function will locate the first ACPI table in XSDT/RSDT based on\r
  Signature in gEfiAcpi20TableGuid system configuration table first, and then\r
  gEfiAcpi10TableGuid system configuration table.\r
  This function will locate in XSDT first, and then RSDT.\r
  For DSDT, this function will locate XDsdt in FADT first, and then Dsdt in\r
  FADT.\r
  For FACS, this function will locate XFirmwareCtrl in FADT first, and then\r
  FirmwareCtrl in FADT.\r
\r
  @param Signature          ACPI table signature.\r
\r
  @return First ACPI table or NULL if not found.\r
\r
**/\r
EFI_ACPI_COMMON_HEADER *\r
EFIAPI\r
EfiLocateFirstAcpiTable (\r
  IN UINT32                     Signature\r
  )\r
{\r
  return EfiLocateNextAcpiTable (Signature, NULL);\r
}\r
Commit	Line	Data
af5e9521 SZ	1	/** @file\r
	2	This module provides help function for finding ACPI table.\r
	3	\r
	4	Copyright (c) 2018, Intel Corporation. All rights reserved.<BR>\r
9344f092	5	SPDX-License-Identifier: BSD-2-Clause-Patent\r
af5e9521 SZ	6	\r
	7	**/\r
	8	\r
	9	#include "UefiLibInternal.h"\r
	10	#include <IndustryStandard/Acpi.h>\r
	11	#include <Guid/Acpi.h>\r
	12	\r
	13	/**\r
	14	This function scans ACPI table in XSDT/RSDT.\r
	15	\r
	16	@param Sdt ACPI XSDT/RSDT.\r
	17	@param TablePointerSize Size of table pointer: 8(XSDT) or 4(RSDT).\r
	18	@param Signature ACPI table signature.\r
	19	@param PreviousTable Pointer to previous returned table to locate\r
	20	next table, or NULL to locate first table.\r
	21	@param PreviousTableLocated Pointer to the indicator about whether the\r
	22	previous returned table could be located, or\r
	23	NULL if PreviousTable is NULL.\r
	24	\r
	25	If PreviousTable is NULL and PreviousTableLocated is not NULL, then ASSERT().\r
	26	If PreviousTable is not NULL and PreviousTableLocated is NULL, then ASSERT().\r
	27	\r
	28	@return ACPI table or NULL if not found.\r
	29	\r
	30	**/\r
	31	EFI_ACPI_COMMON_HEADER *\r
	32	ScanTableInSDT (\r
	33	IN EFI_ACPI_DESCRIPTION_HEADER *Sdt,\r
	34	IN UINTN TablePointerSize,\r
	35	IN UINT32 Signature,\r
	36	IN EFI_ACPI_COMMON_HEADER *PreviousTable, OPTIONAL\r
	37	OUT BOOLEAN *PreviousTableLocated OPTIONAL\r
	38	)\r
	39	{\r
	40	UINTN Index;\r
	41	UINTN EntryCount;\r
	42	UINT64 EntryPtr;\r
	43	UINTN BasePtr;\r
	44	EFI_ACPI_COMMON_HEADER *Table;\r
	45	\r
	46	if (PreviousTableLocated != NULL) {\r
	47	ASSERT (PreviousTable != NULL);\r
	48	*PreviousTableLocated = FALSE;\r
	49	} else {\r
	50	ASSERT (PreviousTable == NULL);\r
	51	}\r
	52	\r
	53	if (Sdt == NULL) {\r
	54	return NULL;\r
	55	}\r
	56	\r
	57	EntryCount = (Sdt->Length - sizeof (EFI_ACPI_DESCRIPTION_HEADER)) / TablePointerSize;\r
	58	\r
	59	BasePtr = (UINTN)(Sdt + 1);\r
	60	for (Index = 0; Index < EntryCount; Index ++) {\r
	61	EntryPtr = 0;\r
	62	CopyMem (&EntryPtr, (VOID )(BasePtr + Index TablePointerSize), TablePointerSize);\r
	63	Table = (EFI_ACPI_COMMON_HEADER *)((UINTN)(EntryPtr));\r
e7ac09b9	64	if ((Table != NULL) && (Table->Signature == Signature)) {\r
af5e9521 SZ	65	if (PreviousTable != NULL) {\r
	66	if (Table == PreviousTable) {\r
	67	*PreviousTableLocated = TRUE;\r
	68	} else if (*PreviousTableLocated) {\r
	69	//\r
	70	// Return next table.\r
	71	//\r
	72	return Table;\r
	73	}\r
	74	} else {\r
	75	//\r
	76	// Return first table.\r
	77	//\r
	78	return Table;\r
	79	}\r
	80	\r
	81	}\r
	82	}\r
	83	\r
	84	return NULL;\r
	85	}\r
	86	\r
	87	/**\r
	88	To locate FACS in FADT.\r
	89	\r
	90	@param Fadt FADT table pointer.\r
	91	\r
	92	@return FACS table pointer or NULL if not found.\r
	93	\r
	94	**/\r
	95	EFI_ACPI_COMMON_HEADER *\r
	96	LocateAcpiFacsFromFadt (\r
	97	IN EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *Fadt\r
	98	)\r
	99	{\r
	100	EFI_ACPI_COMMON_HEADER *Facs;\r
	101	UINT64 Data64;\r
	102	\r
	103	if (Fadt == NULL) {\r
	104	return NULL;\r
	105	}\r
	106	\r
	107	if (Fadt->Header.Revision < EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_REVISION) {\r
	108	Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->FirmwareCtrl;\r
	109	} else {\r
	110	CopyMem (&Data64, &Fadt->XFirmwareCtrl, sizeof(UINT64));\r
	111	if (Data64 != 0) {\r
	112	Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Data64;\r
	113	} else {\r
	114	Facs = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->FirmwareCtrl;\r
	115	}\r
	116	}\r
	117	return Facs;\r
	118	}\r
	119	\r
	120	/**\r
	121	To locate DSDT in FADT.\r
	122	\r
	123	@param Fadt FADT table pointer.\r
	124	\r
	125	@return DSDT table pointer or NULL if not found.\r
	126	\r
	127	**/\r
	128	EFI_ACPI_COMMON_HEADER *\r
129	LocateAcpiDsdtFromFadt (\r
130	IN EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *Fadt\r
131	)\r
132	{\r
133	EFI_ACPI_COMMON_HEADER *Dsdt;\r
134	UINT64 Data64;\r
135	\r
136	if (Fadt == NULL) {\r
137	return NULL;\r
138	}\r
139	\r
140	if (Fadt->Header.Revision < EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_REVISION) {\r
141	Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->Dsdt;\r
142	} else {\r
143	CopyMem (&Data64, &Fadt->XDsdt, sizeof(UINT64));\r
144	if (Data64 != 0) {\r
145	Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Data64;\r
146	} else {\r
147	Dsdt = (EFI_ACPI_COMMON_HEADER *)(UINTN)Fadt->Dsdt;\r
148	}\r
149	}\r
150	return Dsdt;\r
151	}\r
152	\r
153	/**\r
154	To locate ACPI table in ACPI ConfigurationTable.\r
155	\r
156	@param AcpiGuid The GUID used to get ACPI ConfigurationTable.\r
157	@param Signature ACPI table signature.\r
158	@param PreviousTable Pointer to previous returned table to locate\r
159	next table, or NULL to locate first table.\r
160	@param PreviousTableLocated Pointer to the indicator to return whether the\r
161	previous returned table could be located or not,\r
162	or NULL if PreviousTable is NULL.\r
163	\r
164	If PreviousTable is NULL and PreviousTableLocated is not NULL, then ASSERT().\r
165	If PreviousTable is not NULL and PreviousTableLocated is NULL, then ASSERT().\r
166	If AcpiGuid is NULL, then ASSERT().\r
167	\r
168	@return ACPI table or NULL if not found.\r
169	\r
170	**/\r
171	EFI_ACPI_COMMON_HEADER *\r
172	LocateAcpiTableInAcpiConfigurationTable (\r
173	IN EFI_GUID *AcpiGuid,\r
174	IN UINT32 Signature,\r
175	IN EFI_ACPI_COMMON_HEADER *PreviousTable, OPTIONAL\r
176	OUT BOOLEAN *PreviousTableLocated OPTIONAL\r
177	)\r
178	{\r
179	EFI_STATUS Status;\r
180	EFI_ACPI_COMMON_HEADER *Table;\r
181	EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER *Rsdp;\r
182	EFI_ACPI_DESCRIPTION_HEADER *Rsdt;\r
183	EFI_ACPI_DESCRIPTION_HEADER *Xsdt;\r
184	EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *Fadt;\r
185	\r
186	if (PreviousTableLocated != NULL) {\r
187	ASSERT (PreviousTable != NULL);\r
188	*PreviousTableLocated = FALSE;\r
189	} else {\r
190	ASSERT (PreviousTable == NULL);\r
191	}\r
192	\r
193	Rsdp = NULL;\r
194	//\r
195	// Get ACPI ConfigurationTable (RSD_PTR)\r
196	//\r
197	Status = EfiGetSystemConfigurationTable(AcpiGuid, (VOID **)&Rsdp);\r
198	if (EFI_ERROR (Status) \|\| (Rsdp == NULL)) {\r
199	return NULL;\r
200	}\r
201	\r
202	Table = NULL;\r
203	\r
204	//\r
205	// Search XSDT\r
206	//\r
207	if (Rsdp->Revision >= EFI_ACPI_2_0_ROOT_SYSTEM_DESCRIPTION_POINTER_REVISION) {\r
208	Xsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->XsdtAddress;\r
209	if (Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) {\r
210	ASSERT (PreviousTable == NULL);\r
211	//\r
212	// It is to locate DSDT,\r
213	// need to locate FADT first.\r
214	//\r
215	Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
216	Xsdt,\r
217	sizeof (UINT64),\r
218	EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
219	NULL,\r
220	NULL\r
221	);\r
222	Table = LocateAcpiDsdtFromFadt (Fadt);\r
223	} else if (Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) {\r
224	ASSERT (PreviousTable == NULL);\r
225	//\r
226	// It is to locate FACS,\r
227	// need to locate FADT first.\r
228	//\r
229	Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
230	Xsdt,\r
231	sizeof (UINT64),\r
232	EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
233	NULL,\r
234	NULL\r
235	);\r
236	Table = LocateAcpiFacsFromFadt (Fadt);\r
237	} else {\r
238	Table = ScanTableInSDT (\r
239	Xsdt,\r
240	sizeof (UINT64),\r
241	Signature,\r
242	PreviousTable,\r
243	PreviousTableLocated\r
244	);\r
245	}\r
246	}\r
247	\r
248	if (Table != NULL) {\r
249	return Table;\r
250	} else if ((PreviousTableLocated != NULL) &&\r
251	*PreviousTableLocated) {\r
252	//\r
253	// PreviousTable could be located in XSDT,\r
254	// but next table could not be located in XSDT.\r
255	//\r
256	return NULL;\r
257	}\r
258	\r
259	//\r
260	// Search RSDT\r
261	//\r
262	Rsdt = (EFI_ACPI_DESCRIPTION_HEADER *)(UINTN) Rsdp->RsdtAddress;\r
263	if (Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) {\r
264	ASSERT (PreviousTable == NULL);\r
265	//\r
266	// It is to locate DSDT,\r
267	// need to locate FADT first.\r
268	//\r
269	Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
270	Rsdt,\r
271	sizeof (UINT32),\r
272	EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
273	NULL,\r
274	NULL\r
275	);\r
276	Table = LocateAcpiDsdtFromFadt (Fadt);\r
277	} else if (Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE) {\r
278	ASSERT (PreviousTable == NULL);\r
279	//\r
280	// It is to locate FACS,\r
281	// need to locate FADT first.\r
282	//\r
283	Fadt = (EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE *) ScanTableInSDT (\r
284	Rsdt,\r
285	sizeof (UINT32),\r
286	EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE,\r
287	NULL,\r
288	NULL\r
289	);\r
290	Table = LocateAcpiFacsFromFadt (Fadt);\r
291	} else {\r
292	Table = ScanTableInSDT (\r
293	Rsdt,\r
294	sizeof (UINT32),\r
295	Signature,\r
296	PreviousTable,\r
297	PreviousTableLocated\r
298	);\r
299	}\r
300	\r
301	return Table;\r
302	}\r
303	\r
304	/**\r
305	This function locates next ACPI table in XSDT/RSDT based on Signature and\r
306	previous returned Table.\r
307	\r
308	If PreviousTable is NULL:\r
309	This function will locate the first ACPI table in XSDT/RSDT based on\r
310	Signature in gEfiAcpi20TableGuid system configuration table first, and then\r
311	gEfiAcpi10TableGuid system configuration table.\r
312	This function will locate in XSDT first, and then RSDT.\r
313	For DSDT, this function will locate XDsdt in FADT first, and then Dsdt in\r
314	FADT.\r
315	For FACS, this function will locate XFirmwareCtrl in FADT first, and then\r
316	FirmwareCtrl in FADT.\r
317	\r
318	If PreviousTable is not NULL:\r
319	1. If it could be located in XSDT in gEfiAcpi20TableGuid system configuration\r
320	table, then this function will just locate next table in XSDT in\r
321	gEfiAcpi20TableGuid system configuration table.\r
322	2. If it could be located in RSDT in gEfiAcpi20TableGuid system configuration\r
323	table, then this function will just locate next table in RSDT in\r
324	gEfiAcpi20TableGuid system configuration table.\r
325	3. If it could be located in RSDT in gEfiAcpi10TableGuid system configuration\r
326	table, then this function will just locate next table in RSDT in\r
327	gEfiAcpi10TableGuid system configuration table.\r
328	\r
329	It's not supported that PreviousTable is not NULL but PreviousTable->Signature\r
330	is not same with Signature, NULL will be returned.\r
331	\r
332	@param Signature ACPI table signature.\r
333	@param PreviousTable Pointer to previous returned table to locate next\r
334	table, or NULL to locate first table.\r
335	\r
336	@return Next ACPI table or NULL if not found.\r
337	\r
338	**/\r
339	EFI_ACPI_COMMON_HEADER *\r
340	EFIAPI\r
341	EfiLocateNextAcpiTable (\r
342	IN UINT32 Signature,\r
343	IN EFI_ACPI_COMMON_HEADER *PreviousTable OPTIONAL\r
344	)\r
345	{\r
346	EFI_ACPI_COMMON_HEADER *Table;\r
347	BOOLEAN TempPreviousTableLocated;\r
348	BOOLEAN *PreviousTableLocated;\r
349	\r
350	if (PreviousTable != NULL) {\r
351	if (PreviousTable->Signature != Signature) {\r
352	//\r
353	// PreviousTable->Signature is not same with Signature.\r
354	//\r
355	return NULL;\r
356	} else if ((Signature == EFI_ACPI_2_0_FIXED_ACPI_DESCRIPTION_TABLE_SIGNATURE) \|\|\r
357	(Signature == EFI_ACPI_2_0_DIFFERENTIATED_SYSTEM_DESCRIPTION_TABLE_SIGNATURE) \|\|\r
358	(Signature == EFI_ACPI_2_0_FIRMWARE_ACPI_CONTROL_STRUCTURE_SIGNATURE)) {\r
359	//\r
360	// There is only one FADT/DSDT/FACS table,\r
361	// so don't try to locate next one.\r
362	//\r
363	return NULL;\r
364	}\r
365	\r
366	PreviousTableLocated = &TempPreviousTableLocated;\r
367	*PreviousTableLocated = FALSE;\r
368	} else {\r
369	PreviousTableLocated = NULL;\r
370	}\r
371	\r
372	Table = LocateAcpiTableInAcpiConfigurationTable (\r
373	&gEfiAcpi20TableGuid,\r
374	Signature,\r
375	PreviousTable,\r
376	PreviousTableLocated\r
377	);\r
378	if (Table != NULL) {\r
379	return Table;\r
380	} else if ((PreviousTableLocated != NULL) &&\r
381	*PreviousTableLocated) {\r
382	//\r
383	// PreviousTable could be located in gEfiAcpi20TableGuid system\r
384	// configuration table, but next table could not be located in\r
385	// gEfiAcpi20TableGuid system configuration table.\r
386	//\r
387	return NULL;\r
388	}\r
389	\r
390	return LocateAcpiTableInAcpiConfigurationTable (\r
391	&gEfiAcpi10TableGuid,\r
392	Signature,\r
393	PreviousTable,\r
394	PreviousTableLocated\r
395	);\r
396	}\r
397	\r
398	/**\r
399	This function locates first ACPI table in XSDT/RSDT based on Signature.\r
400	\r
401	This function will locate the first ACPI table in XSDT/RSDT based on\r
402	Signature in gEfiAcpi20TableGuid system configuration table first, and then\r
403	gEfiAcpi10TableGuid system configuration table.\r
404	This function will locate in XSDT first, and then RSDT.\r
405	For DSDT, this function will locate XDsdt in FADT first, and then Dsdt in\r
406	FADT.\r
407	For FACS, this function will locate XFirmwareCtrl in FADT first, and then\r
408	FirmwareCtrl in FADT.\r
409	\r
410	@param Signature ACPI table signature.\r
411	\r
412	@return First ACPI table or NULL if not found.\r
413	\r
414	**/\r
415	EFI_ACPI_COMMON_HEADER *\r
416	EFIAPI\r
417	EfiLocateFirstAcpiTable (\r
418	IN UINT32 Signature\r
419	)\r
420	{\r
421	return EfiLocateNextAcpiTable (Signature, NULL);\r
422	}\r