drivers/acpi/acpica/rscreate.c - maze/linux - Git at Google

 /*******************************************************************************
  *
  * Module Name: rscreate - Create resource lists/tables
  *
  ******************************************************************************/

 /*
  * 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.
  */

 #include <acpi/acpi.h>
 #include "accommon.h"
 #include "acresrc.h"
 #include "acnamesp.h"

 #define _COMPONENT          ACPI_RESOURCES
 ACPI_MODULE_NAME("rscreate")

 /*******************************************************************************
  *
  * FUNCTION:    acpi_buffer_to_resource
  *
  * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
  *              aml_buffer_length   - Length of the aml_buffer
  *              resource_ptr        - Where the converted resource is returned
  *
  * RETURN:      Status
  *
  * DESCRIPTION: Convert a raw AML buffer to a resource list
  *
  ******************************************************************************/
 acpi_status
 acpi_buffer_to_resource(u8 *aml_buffer,
 			u16 aml_buffer_length,
 			struct acpi_resource **resource_ptr)
 {
 	acpi_status status;
 	acpi_size list_size_needed;
 	void *resource;
 	void *current_resource_ptr;

 	/*
 	 * Note: we allow AE_AML_NO_RESOURCE_END_TAG, since an end tag
 	 * is not required here.
 	 */

 	/* Get the required length for the converted resource */

 	status = acpi_rs_get_list_length(aml_buffer, aml_buffer_length,
 					 &list_size_needed);
 	if (status == AE_AML_NO_RESOURCE_END_TAG) {
 		status = AE_OK;
 	}
 	if (ACPI_FAILURE(status)) {
 		return (status);
 	}

 	/* Allocate a buffer for the converted resource */

 	resource = ACPI_ALLOCATE_ZEROED(list_size_needed);
 	current_resource_ptr = resource;
 	if (!resource) {
 		return (AE_NO_MEMORY);
 	}

 	/* Perform the AML-to-Resource conversion */

 	status = acpi_ut_walk_aml_resources(NULL, aml_buffer, aml_buffer_length,
 					    acpi_rs_convert_aml_to_resources,
 					    &current_resource_ptr);
 	if (status == AE_AML_NO_RESOURCE_END_TAG) {
 		status = AE_OK;
 	}
 	if (ACPI_FAILURE(status)) {
 		ACPI_FREE(resource);
 	} else {
 		*resource_ptr = resource;
 	}

 	return (status);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_rs_create_resource_list
  *
  * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
  *              output_buffer       - Pointer to the user's buffer
  *
  * RETURN:      Status: AE_OK if okay, else a valid acpi_status code
  *              If output_buffer is not large enough, output_buffer_length
  *              indicates how large output_buffer should be, else it
  *              indicates how may u8 elements of output_buffer are valid.
  *
  * DESCRIPTION: Takes the byte stream returned from a _CRS, _PRS control method
  *              execution and parses the stream to create a linked list
  *              of device resources.
  *
  ******************************************************************************/

 acpi_status
 acpi_rs_create_resource_list(union acpi_operand_object *aml_buffer,
 			     struct acpi_buffer * output_buffer)
 {

 	acpi_status status;
 	u8 *aml_start;
 	acpi_size list_size_needed = 0;
 	u32 aml_buffer_length;
 	void *resource;

 	ACPI_FUNCTION_TRACE(rs_create_resource_list);

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AmlBuffer = %p\n", aml_buffer));

 	/* Params already validated, so we don't re-validate here */

 	aml_buffer_length = aml_buffer->buffer.length;
 	aml_start = aml_buffer->buffer.pointer;

 	/*
 	 * Pass the aml_buffer into a module that can calculate
 	 * the buffer size needed for the linked list
 	 */
 	status = acpi_rs_get_list_length(aml_start, aml_buffer_length,
 					 &list_size_needed);

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Status=%X ListSizeNeeded=%X\n",
 			  status, (u32) list_size_needed));
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/* Validate/Allocate/Clear caller buffer */

 	status = acpi_ut_initialize_buffer(output_buffer, list_size_needed);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/* Do the conversion */

 	resource = output_buffer->pointer;
 	status = acpi_ut_walk_aml_resources(NULL, aml_start, aml_buffer_length,
 					    acpi_rs_convert_aml_to_resources,
 					    &resource);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
 			  output_buffer->pointer, (u32) output_buffer->length));
 	return_ACPI_STATUS(AE_OK);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_rs_create_pci_routing_table
  *
  * PARAMETERS:  package_object          - Pointer to a package containing one
  *                                        of more ACPI_OPERAND_OBJECTs
  *              output_buffer           - Pointer to the user's buffer
  *
  * RETURN:      Status  AE_OK if okay, else a valid acpi_status code.
  *              If the output_buffer is too small, the error will be
  *              AE_BUFFER_OVERFLOW and output_buffer->Length will point
  *              to the size buffer needed.
  *
  * DESCRIPTION: Takes the union acpi_operand_object package and creates a
  *              linked list of PCI interrupt descriptions
  *
  * NOTE: It is the caller's responsibility to ensure that the start of the
  * output buffer is aligned properly (if necessary).
  *
  ******************************************************************************/

 acpi_status
 acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
 				 struct acpi_buffer *output_buffer)
 {
 	u8 *buffer;
 	union acpi_operand_object **top_object_list;
 	union acpi_operand_object **sub_object_list;
 	union acpi_operand_object *obj_desc;
 	acpi_size buffer_size_needed = 0;
 	u32 number_of_elements;
 	u32 index;
 	struct acpi_pci_routing_table *user_prt;
 	struct acpi_namespace_node *node;
 	acpi_status status;
 	struct acpi_buffer path_buffer;

 	ACPI_FUNCTION_TRACE(rs_create_pci_routing_table);

 	/* Params already validated, so we don't re-validate here */

 	/* Get the required buffer length */

 	status = acpi_rs_get_pci_routing_table_length(package_object,
 						      &buffer_size_needed);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "BufferSizeNeeded = %X\n",
 			  (u32) buffer_size_needed));

 	/* Validate/Allocate/Clear caller buffer */

 	status = acpi_ut_initialize_buffer(output_buffer, buffer_size_needed);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/*
 	 * Loop through the ACPI_INTERNAL_OBJECTS - Each object should be a
 	 * package that in turn contains an u64 Address, a u8 Pin,
 	 * a Name, and a u8 source_index.
 	 */
 	top_object_list = package_object->package.elements;
 	number_of_elements = package_object->package.count;
 	buffer = output_buffer->pointer;
 	user_prt = ACPI_CAST_PTR(struct acpi_pci_routing_table, buffer);

 	for (index = 0; index < number_of_elements; index++) {

 		/*
 		 * Point user_prt past this current structure
 		 *
 		 * NOTE: On the first iteration, user_prt->Length will
 		 * be zero because we cleared the return buffer earlier
 		 */
 		buffer += user_prt->length;
 		user_prt = ACPI_CAST_PTR(struct acpi_pci_routing_table, buffer);

 		/*
 		 * Fill in the Length field with the information we have at this point.
 		 * The minus four is to subtract the size of the u8 Source[4] member
 		 * because it is added below.
 		 */
 		user_prt->length = (sizeof(struct acpi_pci_routing_table) - 4);

 		/* Each subpackage must be of length 4 */

 		if ((*top_object_list)->package.count != 4) {
 			ACPI_ERROR((AE_INFO,
 				    "(PRT[%u]) Need package of length 4, found length %u",
 				    index, (*top_object_list)->package.count));
 			return_ACPI_STATUS(AE_AML_PACKAGE_LIMIT);
 		}

 		/*
 		 * Dereference the subpackage.
 		 * The sub_object_list will now point to an array of the four IRQ
 		 * elements: [Address, Pin, Source, source_index]
 		 */
 		sub_object_list = (*top_object_list)->package.elements;

 		/* 1) First subobject: Dereference the PRT.Address */

 		obj_desc = sub_object_list[0];
 		if (!obj_desc || obj_desc->common.type != ACPI_TYPE_INTEGER) {
 			ACPI_ERROR((AE_INFO,
 				    "(PRT[%u].Address) Need Integer, found %s",
 				    index,
 				    acpi_ut_get_object_type_name(obj_desc)));
 			return_ACPI_STATUS(AE_BAD_DATA);
 		}

 		user_prt->address = obj_desc->integer.value;

 		/* 2) Second subobject: Dereference the PRT.Pin */

 		obj_desc = sub_object_list[1];
 		if (!obj_desc || obj_desc->common.type != ACPI_TYPE_INTEGER) {
 			ACPI_ERROR((AE_INFO,
 				    "(PRT[%u].Pin) Need Integer, found %s",
 				    index,
 				    acpi_ut_get_object_type_name(obj_desc)));
 			return_ACPI_STATUS(AE_BAD_DATA);
 		}

 		user_prt->pin = (u32) obj_desc->integer.value;

 		/*
 		 * 3) Third subobject: Dereference the PRT.source_name
 		 * The name may be unresolved (slack mode), so allow a null object
 		 */
 		obj_desc = sub_object_list[2];
 		if (obj_desc) {
 			switch (obj_desc->common.type) {
 			case ACPI_TYPE_LOCAL_REFERENCE:

 				if (obj_desc->reference.class !=
 				    ACPI_REFCLASS_NAME) {
 					ACPI_ERROR((AE_INFO,
 						    "(PRT[%u].Source) Need name, found Reference Class 0x%X",
 						    index,
 						    obj_desc->reference.class));
 					return_ACPI_STATUS(AE_BAD_DATA);
 				}

 				node = obj_desc->reference.node;

 				/* Use *remaining* length of the buffer as max for pathname */

 				path_buffer.length = output_buffer->length -
 				    (u32) ((u8 *) user_prt->source -
 					   (u8 *) output_buffer->pointer);
 				path_buffer.pointer = user_prt->source;

 				status =
 				    acpi_ns_handle_to_pathname((acpi_handle)
 							       node,
 							       &path_buffer);

 				/* +1 to include null terminator */

 				user_prt->length +=
 				    (u32) ACPI_STRLEN(user_prt->source) + 1;
 				break;

 			case ACPI_TYPE_STRING:

 				ACPI_STRCPY(user_prt->source,
 					    obj_desc->string.pointer);

 				/*
 				 * Add to the Length field the length of the string
 				 * (add 1 for terminator)
 				 */
 				user_prt->length += obj_desc->string.length + 1;
 				break;

 			case ACPI_TYPE_INTEGER:
 				/*
 				 * If this is a number, then the Source Name is NULL, since the
 				 * entire buffer was zeroed out, we can leave this alone.
 				 *
 				 * Add to the Length field the length of the u32 NULL
 				 */
 				user_prt->length += sizeof(u32);
 				break;

 			default:

 				ACPI_ERROR((AE_INFO,
 					    "(PRT[%u].Source) Need Ref/String/Integer, found %s",
 					    index,
 					    acpi_ut_get_object_type_name
 					    (obj_desc)));
 				return_ACPI_STATUS(AE_BAD_DATA);
 			}
 		}

 		/* Now align the current length */

 		user_prt->length =
 		    (u32) ACPI_ROUND_UP_TO_64BIT(user_prt->length);

 		/* 4) Fourth subobject: Dereference the PRT.source_index */

 		obj_desc = sub_object_list[3];
 		if (!obj_desc || obj_desc->common.type != ACPI_TYPE_INTEGER) {
 			ACPI_ERROR((AE_INFO,
 				    "(PRT[%u].SourceIndex) Need Integer, found %s",
 				    index,
 				    acpi_ut_get_object_type_name(obj_desc)));
 			return_ACPI_STATUS(AE_BAD_DATA);
 		}

 		user_prt->source_index = (u32) obj_desc->integer.value;

 		/* Point to the next union acpi_operand_object in the top level package */

 		top_object_list++;
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
 			  output_buffer->pointer, (u32) output_buffer->length));
 	return_ACPI_STATUS(AE_OK);
 }

 /*******************************************************************************
  *
  * FUNCTION:    acpi_rs_create_aml_resources
  *
  * PARAMETERS:  resource_list           - Pointer to the resource list buffer
  *              output_buffer           - Where the AML buffer is returned
  *
  * RETURN:      Status  AE_OK if okay, else a valid acpi_status code.
  *              If the output_buffer is too small, the error will be
  *              AE_BUFFER_OVERFLOW and output_buffer->Length will point
  *              to the size buffer needed.
  *
  * DESCRIPTION: Converts a list of device resources to an AML bytestream
  *              to be used as input for the _SRS control method.
  *
  ******************************************************************************/

 acpi_status
 acpi_rs_create_aml_resources(struct acpi_buffer *resource_list,
 			     struct acpi_buffer *output_buffer)
 {
 	acpi_status status;
 	acpi_size aml_size_needed = 0;

 	ACPI_FUNCTION_TRACE(rs_create_aml_resources);

 	/* Params already validated, no need to re-validate here */

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ResourceList Buffer = %p\n",
 			  resource_list->pointer));

 	/* Get the buffer size needed for the AML byte stream */

 	status = acpi_rs_get_aml_length(resource_list->pointer,
 					resource_list->length,
 					&aml_size_needed);

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AmlSizeNeeded=%X, %s\n",
 			  (u32)aml_size_needed, acpi_format_exception(status)));
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/* Validate/Allocate/Clear caller buffer */

 	status = acpi_ut_initialize_buffer(output_buffer, aml_size_needed);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	/* Do the conversion */

 	status = acpi_rs_convert_resources_to_aml(resource_list->pointer,
 						  aml_size_needed,
 						  output_buffer->pointer);
 	if (ACPI_FAILURE(status)) {
 		return_ACPI_STATUS(status);
 	}

 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
 			  output_buffer->pointer, (u32) output_buffer->length));
 	return_ACPI_STATUS(AE_OK);
 }
	/*******************************************************************************
	*
	* Module Name: rscreate - Create resource lists/tables
	*
	******************************************************************************/

	/*
	* 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.
	*/

	#include <acpi/acpi.h>
	#include "accommon.h"
	#include "acresrc.h"
	#include "acnamesp.h"

	#define _COMPONENT ACPI_RESOURCES
	ACPI_MODULE_NAME("rscreate")

	/*******************************************************************************
	*
	* FUNCTION: acpi_buffer_to_resource
	*
	* PARAMETERS: aml_buffer - Pointer to the resource byte stream
	* aml_buffer_length - Length of the aml_buffer
	* resource_ptr - Where the converted resource is returned
	*
	* RETURN: Status
	*
	* DESCRIPTION: Convert a raw AML buffer to a resource list
	*
	******************************************************************************/
	acpi_status
	acpi_buffer_to_resource(u8 *aml_buffer,
	u16 aml_buffer_length,
	struct acpi_resource **resource_ptr)
	{
	acpi_status status;
	acpi_size list_size_needed;
	void *resource;
	void *current_resource_ptr;

	/*
	* Note: we allow AE_AML_NO_RESOURCE_END_TAG, since an end tag
	* is not required here.
	*/

	/* Get the required length for the converted resource */

	status = acpi_rs_get_list_length(aml_buffer, aml_buffer_length,
	&list_size_needed);
	if (status == AE_AML_NO_RESOURCE_END_TAG) {
	status = AE_OK;
	}
	if (ACPI_FAILURE(status)) {
	return (status);
	}

	/* Allocate a buffer for the converted resource */

	resource = ACPI_ALLOCATE_ZEROED(list_size_needed);
	current_resource_ptr = resource;
	if (!resource) {
	return (AE_NO_MEMORY);
	}

	/* Perform the AML-to-Resource conversion */

	status = acpi_ut_walk_aml_resources(NULL, aml_buffer, aml_buffer_length,
	acpi_rs_convert_aml_to_resources,
	&current_resource_ptr);
	if (status == AE_AML_NO_RESOURCE_END_TAG) {
	status = AE_OK;
	}
	if (ACPI_FAILURE(status)) {
	ACPI_FREE(resource);
	} else {
	*resource_ptr = resource;
	}

	return (status);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_rs_create_resource_list
	*
	* PARAMETERS: aml_buffer - Pointer to the resource byte stream
	* output_buffer - Pointer to the user's buffer
	*
	* RETURN: Status: AE_OK if okay, else a valid acpi_status code
	* If output_buffer is not large enough, output_buffer_length
	* indicates how large output_buffer should be, else it
	* indicates how may u8 elements of output_buffer are valid.
	*
	* DESCRIPTION: Takes the byte stream returned from a _CRS, _PRS control method
	* execution and parses the stream to create a linked list
	* of device resources.
	*
	******************************************************************************/

	acpi_status
	acpi_rs_create_resource_list(union acpi_operand_object *aml_buffer,
	struct acpi_buffer * output_buffer)
	{

	acpi_status status;
	u8 *aml_start;
	acpi_size list_size_needed = 0;
	u32 aml_buffer_length;
	void *resource;

	ACPI_FUNCTION_TRACE(rs_create_resource_list);

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AmlBuffer = %p\n", aml_buffer));

	/* Params already validated, so we don't re-validate here */

	aml_buffer_length = aml_buffer->buffer.length;
	aml_start = aml_buffer->buffer.pointer;

	/*
	* Pass the aml_buffer into a module that can calculate
	* the buffer size needed for the linked list
	*/
	status = acpi_rs_get_list_length(aml_start, aml_buffer_length,
	&list_size_needed);

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Status=%X ListSizeNeeded=%X\n",
	status, (u32) list_size_needed));
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/* Validate/Allocate/Clear caller buffer */

	status = acpi_ut_initialize_buffer(output_buffer, list_size_needed);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/* Do the conversion */

	resource = output_buffer->pointer;
	status = acpi_ut_walk_aml_resources(NULL, aml_start, aml_buffer_length,
	acpi_rs_convert_aml_to_resources,
	&resource);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
	output_buffer->pointer, (u32) output_buffer->length));
	return_ACPI_STATUS(AE_OK);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_rs_create_pci_routing_table
	*
	* PARAMETERS: package_object - Pointer to a package containing one
	* of more ACPI_OPERAND_OBJECTs
	* output_buffer - Pointer to the user's buffer
	*
	* RETURN: Status AE_OK if okay, else a valid acpi_status code.
	* If the output_buffer is too small, the error will be
	* AE_BUFFER_OVERFLOW and output_buffer->Length will point
	* to the size buffer needed.
	*
	* DESCRIPTION: Takes the union acpi_operand_object package and creates a
	* linked list of PCI interrupt descriptions
	*
	* NOTE: It is the caller's responsibility to ensure that the start of the
	* output buffer is aligned properly (if necessary).
	*
	******************************************************************************/

	acpi_status
	acpi_rs_create_pci_routing_table(union acpi_operand_object *package_object,
	struct acpi_buffer *output_buffer)
	{
	u8 *buffer;
	union acpi_operand_object **top_object_list;
	union acpi_operand_object **sub_object_list;
	union acpi_operand_object *obj_desc;
	acpi_size buffer_size_needed = 0;
	u32 number_of_elements;
	u32 index;
	struct acpi_pci_routing_table *user_prt;
	struct acpi_namespace_node *node;
	acpi_status status;
	struct acpi_buffer path_buffer;

	ACPI_FUNCTION_TRACE(rs_create_pci_routing_table);

	/* Params already validated, so we don't re-validate here */

	/* Get the required buffer length */

	status = acpi_rs_get_pci_routing_table_length(package_object,
	&buffer_size_needed);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "BufferSizeNeeded = %X\n",
	(u32) buffer_size_needed));

	/* Validate/Allocate/Clear caller buffer */

	status = acpi_ut_initialize_buffer(output_buffer, buffer_size_needed);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/*
	* Loop through the ACPI_INTERNAL_OBJECTS - Each object should be a
	* package that in turn contains an u64 Address, a u8 Pin,
	* a Name, and a u8 source_index.
	*/
	top_object_list = package_object->package.elements;
	number_of_elements = package_object->package.count;
	buffer = output_buffer->pointer;
	user_prt = ACPI_CAST_PTR(struct acpi_pci_routing_table, buffer);

	for (index = 0; index < number_of_elements; index++) {

	/*
	* Point user_prt past this current structure
	*
	* NOTE: On the first iteration, user_prt->Length will
	* be zero because we cleared the return buffer earlier
	*/
	buffer += user_prt->length;
	user_prt = ACPI_CAST_PTR(struct acpi_pci_routing_table, buffer);

	/*
	* Fill in the Length field with the information we have at this point.
	* The minus four is to subtract the size of the u8 Source[4] member
	* because it is added below.
	*/
	user_prt->length = (sizeof(struct acpi_pci_routing_table) - 4);

	/* Each subpackage must be of length 4 */

	if ((*top_object_list)->package.count != 4) {
	ACPI_ERROR((AE_INFO,
	"(PRT[%u]) Need package of length 4, found length %u",
	index, (*top_object_list)->package.count));
	return_ACPI_STATUS(AE_AML_PACKAGE_LIMIT);
	}

	/*
	* Dereference the subpackage.
	* The sub_object_list will now point to an array of the four IRQ
	* elements: [Address, Pin, Source, source_index]
	*/
	sub_object_list = (*top_object_list)->package.elements;

	/* 1) First subobject: Dereference the PRT.Address */

	obj_desc = sub_object_list[0];
	if (!obj_desc \|\| obj_desc->common.type != ACPI_TYPE_INTEGER) {
	ACPI_ERROR((AE_INFO,
	"(PRT[%u].Address) Need Integer, found %s",
	index,
	acpi_ut_get_object_type_name(obj_desc)));
	return_ACPI_STATUS(AE_BAD_DATA);
	}

	user_prt->address = obj_desc->integer.value;

	/* 2) Second subobject: Dereference the PRT.Pin */

	obj_desc = sub_object_list[1];
	if (!obj_desc \|\| obj_desc->common.type != ACPI_TYPE_INTEGER) {
	ACPI_ERROR((AE_INFO,
	"(PRT[%u].Pin) Need Integer, found %s",
	index,
	acpi_ut_get_object_type_name(obj_desc)));
	return_ACPI_STATUS(AE_BAD_DATA);
	}

	user_prt->pin = (u32) obj_desc->integer.value;

	/*
	* 3) Third subobject: Dereference the PRT.source_name
	* The name may be unresolved (slack mode), so allow a null object
	*/
	obj_desc = sub_object_list[2];
	if (obj_desc) {
	switch (obj_desc->common.type) {
	case ACPI_TYPE_LOCAL_REFERENCE:

	if (obj_desc->reference.class !=
	ACPI_REFCLASS_NAME) {
	ACPI_ERROR((AE_INFO,
	"(PRT[%u].Source) Need name, found Reference Class 0x%X",
	index,
	obj_desc->reference.class));
	return_ACPI_STATUS(AE_BAD_DATA);
	}

	node = obj_desc->reference.node;

	/* Use remaining length of the buffer as max for pathname */

	path_buffer.length = output_buffer->length -
	(u32) ((u8 *) user_prt->source -
	(u8 *) output_buffer->pointer);
	path_buffer.pointer = user_prt->source;

	status =
	acpi_ns_handle_to_pathname((acpi_handle)
	node,
	&path_buffer);

	/* +1 to include null terminator */

	user_prt->length +=
	(u32) ACPI_STRLEN(user_prt->source) + 1;
	break;

	case ACPI_TYPE_STRING:

	ACPI_STRCPY(user_prt->source,
	obj_desc->string.pointer);

	/*
	* Add to the Length field the length of the string
	* (add 1 for terminator)
	*/
	user_prt->length += obj_desc->string.length + 1;
	break;

	case ACPI_TYPE_INTEGER:
	/*
	* If this is a number, then the Source Name is NULL, since the
	* entire buffer was zeroed out, we can leave this alone.
	*
	* Add to the Length field the length of the u32 NULL
	*/
	user_prt->length += sizeof(u32);
	break;

	default:

	ACPI_ERROR((AE_INFO,
	"(PRT[%u].Source) Need Ref/String/Integer, found %s",
	index,
	acpi_ut_get_object_type_name
	(obj_desc)));
	return_ACPI_STATUS(AE_BAD_DATA);
	}
	}

	/* Now align the current length */

	user_prt->length =
	(u32) ACPI_ROUND_UP_TO_64BIT(user_prt->length);

	/* 4) Fourth subobject: Dereference the PRT.source_index */

	obj_desc = sub_object_list[3];
	if (!obj_desc \|\| obj_desc->common.type != ACPI_TYPE_INTEGER) {
	ACPI_ERROR((AE_INFO,
	"(PRT[%u].SourceIndex) Need Integer, found %s",
	index,
	acpi_ut_get_object_type_name(obj_desc)));
	return_ACPI_STATUS(AE_BAD_DATA);
	}

	user_prt->source_index = (u32) obj_desc->integer.value;

	/* Point to the next union acpi_operand_object in the top level package */

	top_object_list++;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
	output_buffer->pointer, (u32) output_buffer->length));
	return_ACPI_STATUS(AE_OK);
	}

	/*******************************************************************************
	*
	* FUNCTION: acpi_rs_create_aml_resources
	*
	* PARAMETERS: resource_list - Pointer to the resource list buffer
	* output_buffer - Where the AML buffer is returned
	*
	* RETURN: Status AE_OK if okay, else a valid acpi_status code.
	* If the output_buffer is too small, the error will be
	* AE_BUFFER_OVERFLOW and output_buffer->Length will point
	* to the size buffer needed.
	*
	* DESCRIPTION: Converts a list of device resources to an AML bytestream
	* to be used as input for the _SRS control method.
	*
	******************************************************************************/

	acpi_status
	acpi_rs_create_aml_resources(struct acpi_buffer *resource_list,
	struct acpi_buffer *output_buffer)
	{
	acpi_status status;
	acpi_size aml_size_needed = 0;

	ACPI_FUNCTION_TRACE(rs_create_aml_resources);

	/* Params already validated, no need to re-validate here */

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ResourceList Buffer = %p\n",
	resource_list->pointer));

	/* Get the buffer size needed for the AML byte stream */

	status = acpi_rs_get_aml_length(resource_list->pointer,
	resource_list->length,
	&aml_size_needed);

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "AmlSizeNeeded=%X, %s\n",
	(u32)aml_size_needed, acpi_format_exception(status)));
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/* Validate/Allocate/Clear caller buffer */

	status = acpi_ut_initialize_buffer(output_buffer, aml_size_needed);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	/* Do the conversion */

	status = acpi_rs_convert_resources_to_aml(resource_list->pointer,
	aml_size_needed,
	output_buffer->pointer);
	if (ACPI_FAILURE(status)) {
	return_ACPI_STATUS(status);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "OutputBuffer %p Length %X\n",
	output_buffer->pointer, (u32) output_buffer->length));
	return_ACPI_STATUS(AE_OK);
	}