freebsd-dev/source/components/utilities/utresrc.c
2014-01-15 00:10:20 +00:00

926 lines
24 KiB
C

/*******************************************************************************
*
* Module Name: utresrc - Resource management utilities
*
******************************************************************************/
/*
* Copyright (C) 2000 - 2014, Intel Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#define __UTRESRC_C__
#include "acpi.h"
#include "accommon.h"
#include "acresrc.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME ("utresrc")
#if defined(ACPI_DEBUG_OUTPUT) || defined (ACPI_DISASSEMBLER) || defined (ACPI_DEBUGGER)
/*
* Strings used to decode resource descriptors.
* Used by both the disassembler and the debugger resource dump routines
*/
const char *AcpiGbl_BmDecode[] =
{
"NotBusMaster",
"BusMaster"
};
const char *AcpiGbl_ConfigDecode[] =
{
"0 - Good Configuration",
"1 - Acceptable Configuration",
"2 - Suboptimal Configuration",
"3 - ***Invalid Configuration***",
};
const char *AcpiGbl_ConsumeDecode[] =
{
"ResourceProducer",
"ResourceConsumer"
};
const char *AcpiGbl_DecDecode[] =
{
"PosDecode",
"SubDecode"
};
const char *AcpiGbl_HeDecode[] =
{
"Level",
"Edge"
};
const char *AcpiGbl_IoDecode[] =
{
"Decode10",
"Decode16"
};
const char *AcpiGbl_LlDecode[] =
{
"ActiveHigh",
"ActiveLow"
};
const char *AcpiGbl_MaxDecode[] =
{
"MaxNotFixed",
"MaxFixed"
};
const char *AcpiGbl_MemDecode[] =
{
"NonCacheable",
"Cacheable",
"WriteCombining",
"Prefetchable"
};
const char *AcpiGbl_MinDecode[] =
{
"MinNotFixed",
"MinFixed"
};
const char *AcpiGbl_MtpDecode[] =
{
"AddressRangeMemory",
"AddressRangeReserved",
"AddressRangeACPI",
"AddressRangeNVS"
};
const char *AcpiGbl_RngDecode[] =
{
"InvalidRanges",
"NonISAOnlyRanges",
"ISAOnlyRanges",
"EntireRange"
};
const char *AcpiGbl_RwDecode[] =
{
"ReadOnly",
"ReadWrite"
};
const char *AcpiGbl_ShrDecode[] =
{
"Exclusive",
"Shared",
"ExclusiveAndWake", /* ACPI 5.0 */
"SharedAndWake" /* ACPI 5.0 */
};
const char *AcpiGbl_SizDecode[] =
{
"Transfer8",
"Transfer8_16",
"Transfer16",
"InvalidSize"
};
const char *AcpiGbl_TrsDecode[] =
{
"DenseTranslation",
"SparseTranslation"
};
const char *AcpiGbl_TtpDecode[] =
{
"TypeStatic",
"TypeTranslation"
};
const char *AcpiGbl_TypDecode[] =
{
"Compatibility",
"TypeA",
"TypeB",
"TypeF"
};
const char *AcpiGbl_PpcDecode[] =
{
"PullDefault",
"PullUp",
"PullDown",
"PullNone"
};
const char *AcpiGbl_IorDecode[] =
{
"IoRestrictionNone",
"IoRestrictionInputOnly",
"IoRestrictionOutputOnly",
"IoRestrictionNoneAndPreserve"
};
const char *AcpiGbl_DtsDecode[] =
{
"Width8bit",
"Width16bit",
"Width32bit",
"Width64bit",
"Width128bit",
"Width256bit",
};
/* GPIO connection type */
const char *AcpiGbl_CtDecode[] =
{
"Interrupt",
"I/O"
};
/* Serial bus type */
const char *AcpiGbl_SbtDecode[] =
{
"/* UNKNOWN serial bus type */",
"I2C",
"SPI",
"UART"
};
/* I2C serial bus access mode */
const char *AcpiGbl_AmDecode[] =
{
"AddressingMode7Bit",
"AddressingMode10Bit"
};
/* I2C serial bus slave mode */
const char *AcpiGbl_SmDecode[] =
{
"ControllerInitiated",
"DeviceInitiated"
};
/* SPI serial bus wire mode */
const char *AcpiGbl_WmDecode[] =
{
"FourWireMode",
"ThreeWireMode"
};
/* SPI serial clock phase */
const char *AcpiGbl_CphDecode[] =
{
"ClockPhaseFirst",
"ClockPhaseSecond"
};
/* SPI serial bus clock polarity */
const char *AcpiGbl_CpoDecode[] =
{
"ClockPolarityLow",
"ClockPolarityHigh"
};
/* SPI serial bus device polarity */
const char *AcpiGbl_DpDecode[] =
{
"PolarityLow",
"PolarityHigh"
};
/* UART serial bus endian */
const char *AcpiGbl_EdDecode[] =
{
"LittleEndian",
"BigEndian"
};
/* UART serial bus bits per byte */
const char *AcpiGbl_BpbDecode[] =
{
"DataBitsFive",
"DataBitsSix",
"DataBitsSeven",
"DataBitsEight",
"DataBitsNine",
"/* UNKNOWN Bits per byte */",
"/* UNKNOWN Bits per byte */",
"/* UNKNOWN Bits per byte */"
};
/* UART serial bus stop bits */
const char *AcpiGbl_SbDecode[] =
{
"StopBitsNone",
"StopBitsOne",
"StopBitsOnePlusHalf",
"StopBitsTwo"
};
/* UART serial bus flow control */
const char *AcpiGbl_FcDecode[] =
{
"FlowControlNone",
"FlowControlHardware",
"FlowControlXON",
"/* UNKNOWN flow control keyword */"
};
/* UART serial bus parity type */
const char *AcpiGbl_PtDecode[] =
{
"ParityTypeNone",
"ParityTypeEven",
"ParityTypeOdd",
"ParityTypeMark",
"ParityTypeSpace",
"/* UNKNOWN parity keyword */",
"/* UNKNOWN parity keyword */",
"/* UNKNOWN parity keyword */"
};
#endif
/*
* Base sizes of the raw AML resource descriptors, indexed by resource type.
* Zero indicates a reserved (and therefore invalid) resource type.
*/
const UINT8 AcpiGbl_ResourceAmlSizes[] =
{
/* Small descriptors */
0,
0,
0,
0,
ACPI_AML_SIZE_SMALL (AML_RESOURCE_IRQ),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_DMA),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_START_DEPENDENT),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_END_DEPENDENT),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_IO),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_FIXED_IO),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_FIXED_DMA),
0,
0,
0,
ACPI_AML_SIZE_SMALL (AML_RESOURCE_VENDOR_SMALL),
ACPI_AML_SIZE_SMALL (AML_RESOURCE_END_TAG),
/* Large descriptors */
0,
ACPI_AML_SIZE_LARGE (AML_RESOURCE_MEMORY24),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_GENERIC_REGISTER),
0,
ACPI_AML_SIZE_LARGE (AML_RESOURCE_VENDOR_LARGE),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_MEMORY32),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_FIXED_MEMORY32),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS32),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS16),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_EXTENDED_IRQ),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_ADDRESS64),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_EXTENDED_ADDRESS64),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_GPIO),
0,
ACPI_AML_SIZE_LARGE (AML_RESOURCE_COMMON_SERIALBUS),
};
const UINT8 AcpiGbl_ResourceAmlSerialBusSizes[] =
{
0,
ACPI_AML_SIZE_LARGE (AML_RESOURCE_I2C_SERIALBUS),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_SPI_SERIALBUS),
ACPI_AML_SIZE_LARGE (AML_RESOURCE_UART_SERIALBUS),
};
/*
* Resource types, used to validate the resource length field.
* The length of fixed-length types must match exactly, variable
* lengths must meet the minimum required length, etc.
* Zero indicates a reserved (and therefore invalid) resource type.
*/
static const UINT8 AcpiGbl_ResourceTypes[] =
{
/* Small descriptors */
0,
0,
0,
0,
ACPI_SMALL_VARIABLE_LENGTH, /* 04 IRQ */
ACPI_FIXED_LENGTH, /* 05 DMA */
ACPI_SMALL_VARIABLE_LENGTH, /* 06 StartDependentFunctions */
ACPI_FIXED_LENGTH, /* 07 EndDependentFunctions */
ACPI_FIXED_LENGTH, /* 08 IO */
ACPI_FIXED_LENGTH, /* 09 FixedIO */
ACPI_FIXED_LENGTH, /* 0A FixedDMA */
0,
0,
0,
ACPI_VARIABLE_LENGTH, /* 0E VendorShort */
ACPI_FIXED_LENGTH, /* 0F EndTag */
/* Large descriptors */
0,
ACPI_FIXED_LENGTH, /* 01 Memory24 */
ACPI_FIXED_LENGTH, /* 02 GenericRegister */
0,
ACPI_VARIABLE_LENGTH, /* 04 VendorLong */
ACPI_FIXED_LENGTH, /* 05 Memory32 */
ACPI_FIXED_LENGTH, /* 06 Memory32Fixed */
ACPI_VARIABLE_LENGTH, /* 07 Dword* address */
ACPI_VARIABLE_LENGTH, /* 08 Word* address */
ACPI_VARIABLE_LENGTH, /* 09 ExtendedIRQ */
ACPI_VARIABLE_LENGTH, /* 0A Qword* address */
ACPI_FIXED_LENGTH, /* 0B Extended* address */
ACPI_VARIABLE_LENGTH, /* 0C Gpio* */
0,
ACPI_VARIABLE_LENGTH /* 0E *SerialBus */
};
/*******************************************************************************
*
* FUNCTION: AcpiUtWalkAmlResources
*
* PARAMETERS: WalkState - Current walk info
* PARAMETERS: Aml - Pointer to the raw AML resource template
* AmlLength - Length of the entire template
* UserFunction - Called once for each descriptor found. If
* NULL, a pointer to the EndTag is returned
* Context - Passed to UserFunction
*
* RETURN: Status
*
* DESCRIPTION: Walk a raw AML resource list(buffer). User function called
* once for each resource found.
*
******************************************************************************/
ACPI_STATUS
AcpiUtWalkAmlResources (
ACPI_WALK_STATE *WalkState,
UINT8 *Aml,
ACPI_SIZE AmlLength,
ACPI_WALK_AML_CALLBACK UserFunction,
void **Context)
{
ACPI_STATUS Status;
UINT8 *EndAml;
UINT8 ResourceIndex;
UINT32 Length;
UINT32 Offset = 0;
UINT8 EndTag[2] = {0x79, 0x00};
ACPI_FUNCTION_TRACE (UtWalkAmlResources);
/* The absolute minimum resource template is one EndTag descriptor */
if (AmlLength < sizeof (AML_RESOURCE_END_TAG))
{
return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
}
/* Point to the end of the resource template buffer */
EndAml = Aml + AmlLength;
/* Walk the byte list, abort on any invalid descriptor type or length */
while (Aml < EndAml)
{
/* Validate the Resource Type and Resource Length */
Status = AcpiUtValidateResource (WalkState, Aml, &ResourceIndex);
if (ACPI_FAILURE (Status))
{
/*
* Exit on failure. Cannot continue because the descriptor length
* may be bogus also.
*/
return_ACPI_STATUS (Status);
}
/* Get the length of this descriptor */
Length = AcpiUtGetDescriptorLength (Aml);
/* Invoke the user function */
if (UserFunction)
{
Status = UserFunction (Aml, Length, Offset, ResourceIndex, Context);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
}
/* An EndTag descriptor terminates this resource template */
if (AcpiUtGetResourceType (Aml) == ACPI_RESOURCE_NAME_END_TAG)
{
/*
* There must be at least one more byte in the buffer for
* the 2nd byte of the EndTag
*/
if ((Aml + 1) >= EndAml)
{
return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
}
/* Return the pointer to the EndTag if requested */
if (!UserFunction)
{
*Context = Aml;
}
/* Normal exit */
return_ACPI_STATUS (AE_OK);
}
Aml += Length;
Offset += Length;
}
/* Did not find an EndTag descriptor */
if (UserFunction)
{
/* Insert an EndTag anyway. AcpiRsGetListLength always leaves room */
(void) AcpiUtValidateResource (WalkState, EndTag, &ResourceIndex);
Status = UserFunction (EndTag, 2, Offset, ResourceIndex, Context);
if (ACPI_FAILURE (Status))
{
return_ACPI_STATUS (Status);
}
}
return_ACPI_STATUS (AE_AML_NO_RESOURCE_END_TAG);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtValidateResource
*
* PARAMETERS: WalkState - Current walk info
* Aml - Pointer to the raw AML resource descriptor
* ReturnIndex - Where the resource index is returned. NULL
* if the index is not required.
*
* RETURN: Status, and optionally the Index into the global resource tables
*
* DESCRIPTION: Validate an AML resource descriptor by checking the Resource
* Type and Resource Length. Returns an index into the global
* resource information/dispatch tables for later use.
*
******************************************************************************/
ACPI_STATUS
AcpiUtValidateResource (
ACPI_WALK_STATE *WalkState,
void *Aml,
UINT8 *ReturnIndex)
{
AML_RESOURCE *AmlResource;
UINT8 ResourceType;
UINT8 ResourceIndex;
ACPI_RS_LENGTH ResourceLength;
ACPI_RS_LENGTH MinimumResourceLength;
ACPI_FUNCTION_ENTRY ();
/*
* 1) Validate the ResourceType field (Byte 0)
*/
ResourceType = ACPI_GET8 (Aml);
/*
* Byte 0 contains the descriptor name (Resource Type)
* Examine the large/small bit in the resource header
*/
if (ResourceType & ACPI_RESOURCE_NAME_LARGE)
{
/* Verify the large resource type (name) against the max */
if (ResourceType > ACPI_RESOURCE_NAME_LARGE_MAX)
{
goto InvalidResource;
}
/*
* Large Resource Type -- bits 6:0 contain the name
* Translate range 0x80-0x8B to index range 0x10-0x1B
*/
ResourceIndex = (UINT8) (ResourceType - 0x70);
}
else
{
/*
* Small Resource Type -- bits 6:3 contain the name
* Shift range to index range 0x00-0x0F
*/
ResourceIndex = (UINT8)
((ResourceType & ACPI_RESOURCE_NAME_SMALL_MASK) >> 3);
}
/*
* Check validity of the resource type, via AcpiGbl_ResourceTypes. Zero
* indicates an invalid resource.
*/
if (!AcpiGbl_ResourceTypes[ResourceIndex])
{
goto InvalidResource;
}
/*
* Validate the ResourceLength field. This ensures that the length
* is at least reasonable, and guarantees that it is non-zero.
*/
ResourceLength = AcpiUtGetResourceLength (Aml);
MinimumResourceLength = AcpiGbl_ResourceAmlSizes[ResourceIndex];
/* Validate based upon the type of resource - fixed length or variable */
switch (AcpiGbl_ResourceTypes[ResourceIndex])
{
case ACPI_FIXED_LENGTH:
/* Fixed length resource, length must match exactly */
if (ResourceLength != MinimumResourceLength)
{
goto BadResourceLength;
}
break;
case ACPI_VARIABLE_LENGTH:
/* Variable length resource, length must be at least the minimum */
if (ResourceLength < MinimumResourceLength)
{
goto BadResourceLength;
}
break;
case ACPI_SMALL_VARIABLE_LENGTH:
/* Small variable length resource, length can be (Min) or (Min-1) */
if ((ResourceLength > MinimumResourceLength) ||
(ResourceLength < (MinimumResourceLength - 1)))
{
goto BadResourceLength;
}
break;
default:
/* Shouldn't happen (because of validation earlier), but be sure */
goto InvalidResource;
}
AmlResource = ACPI_CAST_PTR (AML_RESOURCE, Aml);
if (ResourceType == ACPI_RESOURCE_NAME_SERIAL_BUS)
{
/* Validate the BusType field */
if ((AmlResource->CommonSerialBus.Type == 0) ||
(AmlResource->CommonSerialBus.Type > AML_RESOURCE_MAX_SERIALBUSTYPE))
{
if (WalkState)
{
ACPI_ERROR ((AE_INFO,
"Invalid/unsupported SerialBus resource descriptor: BusType 0x%2.2X",
AmlResource->CommonSerialBus.Type));
}
return (AE_AML_INVALID_RESOURCE_TYPE);
}
}
/* Optionally return the resource table index */
if (ReturnIndex)
{
*ReturnIndex = ResourceIndex;
}
return (AE_OK);
InvalidResource:
if (WalkState)
{
ACPI_ERROR ((AE_INFO,
"Invalid/unsupported resource descriptor: Type 0x%2.2X",
ResourceType));
}
return (AE_AML_INVALID_RESOURCE_TYPE);
BadResourceLength:
if (WalkState)
{
ACPI_ERROR ((AE_INFO,
"Invalid resource descriptor length: Type "
"0x%2.2X, Length 0x%4.4X, MinLength 0x%4.4X",
ResourceType, ResourceLength, MinimumResourceLength));
}
return (AE_AML_BAD_RESOURCE_LENGTH);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtGetResourceType
*
* PARAMETERS: Aml - Pointer to the raw AML resource descriptor
*
* RETURN: The Resource Type with no extraneous bits (except the
* Large/Small descriptor bit -- this is left alone)
*
* DESCRIPTION: Extract the Resource Type/Name from the first byte of
* a resource descriptor.
*
******************************************************************************/
UINT8
AcpiUtGetResourceType (
void *Aml)
{
ACPI_FUNCTION_ENTRY ();
/*
* Byte 0 contains the descriptor name (Resource Type)
* Examine the large/small bit in the resource header
*/
if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
{
/* Large Resource Type -- bits 6:0 contain the name */
return (ACPI_GET8 (Aml));
}
else
{
/* Small Resource Type -- bits 6:3 contain the name */
return ((UINT8) (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_SMALL_MASK));
}
}
/*******************************************************************************
*
* FUNCTION: AcpiUtGetResourceLength
*
* PARAMETERS: Aml - Pointer to the raw AML resource descriptor
*
* RETURN: Byte Length
*
* DESCRIPTION: Get the "Resource Length" of a raw AML descriptor. By
* definition, this does not include the size of the descriptor
* header or the length field itself.
*
******************************************************************************/
UINT16
AcpiUtGetResourceLength (
void *Aml)
{
ACPI_RS_LENGTH ResourceLength;
ACPI_FUNCTION_ENTRY ();
/*
* Byte 0 contains the descriptor name (Resource Type)
* Examine the large/small bit in the resource header
*/
if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
{
/* Large Resource type -- bytes 1-2 contain the 16-bit length */
ACPI_MOVE_16_TO_16 (&ResourceLength, ACPI_ADD_PTR (UINT8, Aml, 1));
}
else
{
/* Small Resource type -- bits 2:0 of byte 0 contain the length */
ResourceLength = (UINT16) (ACPI_GET8 (Aml) &
ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK);
}
return (ResourceLength);
}
/*******************************************************************************
*
* FUNCTION: AcpiUtGetResourceHeaderLength
*
* PARAMETERS: Aml - Pointer to the raw AML resource descriptor
*
* RETURN: Length of the AML header (depends on large/small descriptor)
*
* DESCRIPTION: Get the length of the header for this resource.
*
******************************************************************************/
UINT8
AcpiUtGetResourceHeaderLength (
void *Aml)
{
ACPI_FUNCTION_ENTRY ();
/* Examine the large/small bit in the resource header */
if (ACPI_GET8 (Aml) & ACPI_RESOURCE_NAME_LARGE)
{
return (sizeof (AML_RESOURCE_LARGE_HEADER));
}
else
{
return (sizeof (AML_RESOURCE_SMALL_HEADER));
}
}
/*******************************************************************************
*
* FUNCTION: AcpiUtGetDescriptorLength
*
* PARAMETERS: Aml - Pointer to the raw AML resource descriptor
*
* RETURN: Byte length
*
* DESCRIPTION: Get the total byte length of a raw AML descriptor, including the
* length of the descriptor header and the length field itself.
* Used to walk descriptor lists.
*
******************************************************************************/
UINT32
AcpiUtGetDescriptorLength (
void *Aml)
{
ACPI_FUNCTION_ENTRY ();
/*
* Get the Resource Length (does not include header length) and add
* the header length (depends on if this is a small or large resource)
*/
return (AcpiUtGetResourceLength (Aml) +
AcpiUtGetResourceHeaderLength (Aml));
}
/*******************************************************************************
*
* FUNCTION: AcpiUtGetResourceEndTag
*
* PARAMETERS: ObjDesc - The resource template buffer object
* EndTag - Where the pointer to the EndTag is returned
*
* RETURN: Status, pointer to the end tag
*
* DESCRIPTION: Find the EndTag resource descriptor in an AML resource template
* Note: allows a buffer length of zero.
*
******************************************************************************/
ACPI_STATUS
AcpiUtGetResourceEndTag (
ACPI_OPERAND_OBJECT *ObjDesc,
UINT8 **EndTag)
{
ACPI_STATUS Status;
ACPI_FUNCTION_TRACE (UtGetResourceEndTag);
/* Allow a buffer length of zero */
if (!ObjDesc->Buffer.Length)
{
*EndTag = ObjDesc->Buffer.Pointer;
return_ACPI_STATUS (AE_OK);
}
/* Validate the template and get a pointer to the EndTag */
Status = AcpiUtWalkAmlResources (NULL, ObjDesc->Buffer.Pointer,
ObjDesc->Buffer.Length, NULL, (void **) EndTag);
return_ACPI_STATUS (Status);
}