rscalc.c

h内核

/*******************************************************************************
 *
 * Module Name: rscalc - Calculate stream and list lengths
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2005, R. Byron Moore
 * 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 <acpi/acresrc.h>
#include <acpi/amlcode.h>
#include <acpi/acnamesp.h>

#define _COMPONENT          ACPI_RESOURCES
	 ACPI_MODULE_NAME    ("rscalc")


/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_byte_stream_length
 *
 * PARAMETERS:  linked_list         - Pointer to the resource linked list
 *              size_needed         - u32 pointer of the size buffer needed
 *                                    to properly return the parsed data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes the resource byte stream and parses it once, calculating
 *              the size buffer needed to hold the linked list that conveys
 *              the resource data.
 *
 ******************************************************************************/

acpi_status
acpi_rs_get_byte_stream_length (
	struct acpi_resource            *linked_list,
	acpi_size                       *size_needed)
{
	acpi_size                       byte_stream_size_needed = 0;
	acpi_size                       segment_size;
	u8                              done = FALSE;


	ACPI_FUNCTION_TRACE ("rs_get_byte_stream_length");


	while (!done) {
		/*
		 * Init the variable that will hold the size to add to the total.
		 */
		segment_size = 0;

		switch (linked_list->id) {
		case ACPI_RSTYPE_IRQ:
			/*
			 * IRQ Resource
			 * For an IRQ Resource, Byte 3, although optional, will always be
			 * created - it holds IRQ information.
			 */
			segment_size = 4;
			break;

		case ACPI_RSTYPE_DMA:
			/*
			 * DMA Resource
			 * For this resource the size is static
			 */
			segment_size = 3;
			break;

		case ACPI_RSTYPE_START_DPF:
			/*
			 * Start Dependent Functions Resource
			 * For a start_dependent_functions Resource, Byte 1, although
			 * optional, will always be created.
			 */
			segment_size = 2;
			break;

		case ACPI_RSTYPE_END_DPF:
			/*
			 * End Dependent Functions Resource
			 * For this resource the size is static
			 */
			segment_size = 1;
			break;

		case ACPI_RSTYPE_IO:
			/*
			 * IO Port Resource
			 * For this resource the size is static
			 */
			segment_size = 8;
			break;

		case ACPI_RSTYPE_FIXED_IO:
			/*
			 * Fixed IO Port Resource
			 * For this resource the size is static
			 */
			segment_size = 4;
			break;

		case ACPI_RSTYPE_VENDOR:
			/*
			 * Vendor Defined Resource
			 * For a Vendor Specific resource, if the Length is between 1 and 7
			 * it will be created as a Small Resource data type, otherwise it
			 * is a Large Resource data type.
			 */
			if (linked_list->data.vendor_specific.length > 7) {
				segment_size = 3;
			}
			else {
				segment_size = 1;
			}
			segment_size += linked_list->data.vendor_specific.length;
			break;

		case ACPI_RSTYPE_END_TAG:
			/*
			 * End Tag
			 * For this resource the size is static
			 */
			segment_size = 2;
			done = TRUE;
			break;

		case ACPI_RSTYPE_MEM24:
			/*
			 * 24-Bit Memory Resource
			 * For this resource the size is static
			 */
			segment_size = 12;
			break;

		case ACPI_RSTYPE_MEM32:
			/*
			 * 32-Bit Memory Range Resource
			 * For this resource the size is static
			 */
			segment_size = 20;
			break;

		case ACPI_RSTYPE_FIXED_MEM32:
			/*
			 * 32-Bit Fixed Memory Resource
			 * For this resource the size is static
			 */
			segment_size = 12;
			break;

		case ACPI_RSTYPE_ADDRESS16:
			/*
			 * 16-Bit Address Resource
			 * The base size of this byte stream is 16. If a Resource Source
			 * string is not NULL, add 1 for the Index + the length of the null
			 * terminated string Resource Source + 1 for the null.
			 */
			segment_size = 16;

			if (linked_list->data.address16.resource_source.string_ptr) {
				segment_size += linked_list->data.address16.resource_source.string_length;
				segment_size++;
			}
			break;

		case ACPI_RSTYPE_ADDRESS32:
			/*
			 * 32-Bit Address Resource
			 * The base size of this byte stream is 26. If a Resource
			 * Source string is not NULL, add 1 for the Index + the
			 * length of the null terminated string Resource Source +
			 * 1 for the null.
			 */
			segment_size = 26;

			if (linked_list->data.address32.resource_source.string_ptr) {
				segment_size += linked_list->data.address32.resource_source.string_length;
				segment_size++;
			}
			break;

		case ACPI_RSTYPE_ADDRESS64:
			/*
			 * 64-Bit Address Resource
			 * The base size of this byte stream is 46. If a resource_source
			 * string is not NULL, add 1 for the Index + the length of the null
			 * terminated string Resource Source + 1 for the null.
			 */
			segment_size = 46;

			if (linked_list->data.address64.resource_source.string_ptr) {
				segment_size += linked_list->data.address64.resource_source.string_length;
				segment_size++;
			}
			break;

		case ACPI_RSTYPE_EXT_IRQ:
			/*
			 * Extended IRQ Resource
			 * The base size of this byte stream is 9. This is for an Interrupt
			 * table length of 1.  For each additional interrupt, add 4.
			 * If a Resource Source string is not NULL, add 1 for the
			 * Index + the length of the null terminated string
			 * Resource Source + 1 for the null.
			 */
			segment_size = 9 +
				(((acpi_size) linked_list->data.extended_irq.number_of_interrupts - 1) * 4);

			if (linked_list->data.extended_irq.resource_source.string_ptr) {
				segment_size += linked_list->data.extended_irq.resource_source.string_length;
				segment_size++;
			}
			break;

		default:
			/*
			 * If we get here, everything is out of sync, exit with error
			 */
			return_ACPI_STATUS (AE_AML_INVALID_RESOURCE_TYPE);

		} /* switch (linked_list->Id) */

		/*
		 * Update the total
		 */
		byte_stream_size_needed += segment_size;

		/*
		 * Point to the next object
		 */
		linked_list = ACPI_PTR_ADD (struct acpi_resource,
				  linked_list, linked_list->length);
	}

	/*
	 * This is the data the caller needs
	 */
	*size_needed = byte_stream_size_needed;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_list_length
 *
 * PARAMETERS:  byte_stream_buffer      - Pointer to the resource byte stream
 *              byte_stream_buffer_length - Size of byte_stream_buffer
 *              size_needed             - u32 pointer of the size buffer
 *                                        needed to properly return the
 *                                        parsed data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes the resource byte stream and parses it once, calculating
 *              the size buffer needed to hold the linked list that conveys
 *              the resource data.
 *
 ******************************************************************************/

acpi_status
acpi_rs_get_list_length (
	u8                              *byte_stream_buffer,
	u32                             byte_stream_buffer_length,
	acpi_size                       *size_needed)
{
	u32                             buffer_size = 0;
	u32                             bytes_parsed = 0;
	u8                              number_of_interrupts = 0;
	u8                              number_of_channels = 0;
	u8                              resource_type;
	u32                             structure_size;
	u32                             bytes_consumed;
	u8                              *buffer;
	u8                              temp8;
	u16                             temp16;
	u8                              index;
	u8                              additional_bytes;


	ACPI_FUNCTION_TRACE ("rs_get_list_length");


	while (bytes_parsed < byte_stream_buffer_length) {
		/*
		 * The next byte in the stream is the resource type
		 */
		resource_type = acpi_rs_get_resource_type (*byte_stream_buffer);

		switch (resource_type) {
		case ACPI_RDESC_TYPE_MEMORY_24:
			/*
			 * 24-Bit Memory Resource
			 */
			bytes_consumed = 12;

			structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_mem24);
			break;


		case ACPI_RDESC_TYPE_LARGE_VENDOR:
			/*
			 * Vendor Defined Resource
			 */
			buffer = byte_stream_buffer;
			++buffer;

			ACPI_MOVE_16_TO_16 (&temp16, buffer);
			bytes_consumed = temp16 + 3;

			/*
			 * Ensure a 32-bit boundary for the structure
			 */
			temp16 = (u16) ACPI_ROUND_UP_to_32_bITS (temp16);

			structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_vendor) +
					   (temp16 * sizeof (u8));
			break;


		case ACPI_RDESC_TYPE_MEMORY_32:
			/*
			 * 32-Bit Memory Range Resource
			 */
			bytes_consumed = 20;

			structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_mem32);
			break;


		case ACPI_RDESC_TYPE_FIXED_MEMORY_32:
			/*
			 * 32-Bit Fixed Memory Resource
			 */
			bytes_consumed = 12;

			structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_fixed_mem32);
			break;


		case ACPI_RDESC_TYPE_QWORD_ADDRESS_SPACE:
			/*
			 * 64-Bit Address Resource
			 */
			buffer = byte_stream_buffer;

			++buffer;
			ACPI_MOVE_16_TO_16 (&temp16, buffer);

			bytes_consumed = temp16 + 3;

			/*
			 * Resource Source Index and Resource Source are optional elements.
			 * Check the length of the Bytestream.  If it is greater than 43,
			 * that means that an Index exists and is followed by a null
			 * terminated string.  Therefore, set the temp variable to the
			 * length minus the minimum byte stream length plus the byte for
			 * the Index to determine the size of the NULL terminated string.
			 */
			if (43 < temp16) {
				temp8 = (u8) (temp16 - 44);
			}
			else {
				temp8 = 0;
			}

			/*
			 * Ensure a 64-bit boundary for the structure
			 */
			temp8 = (u8) ACPI_ROUND_UP_to_64_bITS (temp8);

			structure_size = ACPI_SIZEOF_RESOURCE (struct acpi_resource_address64) +
					   (temp8 * sizeof (u8));
			break;