rscalc.c

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/*******************************************************************************
 *
 * Module Name: rscalc - Acpi_rs_calculate_byte_stream_length
 *                       Acpi_rs_calculate_list_length
 *              $Revision: 16 $
 *
 ******************************************************************************/

/*
 *  Copyright (C) 2000 R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "acpi.h"
#include "acresrc.h"

#define _COMPONENT          RESOURCE_MANAGER
	 MODULE_NAME         ("rscalc")


/*******************************************************************************
 *
 * FUNCTION:    Acpi_rs_calculate_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  AE_OK if okay, else a valid ACPI_STATUS code
 *
 * 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_calculate_byte_stream_length (
	RESOURCE                *linked_list,
	u32                     *size_needed)
{
	u32                     byte_stream_size_needed = 0;
	u32                     segment_size;
	EXTENDED_IRQ_RESOURCE   *ex_irq = NULL;
	u8                      done = FALSE;


	while (!done) {

		/*
		 * Init the variable that will hold the size to add to the
		 *  total.
		 */
		segment_size = 0;

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

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

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

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

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

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

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

		case memory24:
			/*
			 * 24-Bit Memory Resource
			 */
			/*
			 * For this resource the size is static
			 */
			segment_size = 12;
			break;

		case memory32:
			/*
			 * 32-Bit Memory Range Resource
			 */
			/*
			 * For this resource the size is static
			 */
			segment_size = 20;
			break;

		case fixed_memory32:
			/*
			 * 32-Bit Fixed Memory Resource
			 */
			/*
			 * For this resource the size is static
			 */
			segment_size = 12;
			break;

		case 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(NULL != linked_list->data.address16.resource_source) {
				segment_size += (1 +
					linked_list->data.address16.resource_source_string_length);
			}
			break;

		case 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(NULL != linked_list->data.address16.resource_source) {
				segment_size += (1 +
					linked_list->data.address16.resource_source_string_length);
			}
			break;

		case extended_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;

			segment_size +=
				(linked_list->data.extended_irq.number_of_interrupts -
				 1) * 4;

			if(NULL != ex_irq->resource_source) {
				segment_size += (1 +
					linked_list->data.extended_irq.resource_source_string_length);
			}
			break;

		default:
			/*
			 * If we get here, everything is out of sync,
			 *  so exit with an error
			 */
			return (AE_AML_ERROR);
			break;

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

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

		/*
		 * Point to the next object
		 */
		linked_list = (RESOURCE *) ((NATIVE_UINT) linked_list +
				  (NATIVE_UINT) linked_list->length);
	}

	/*
	 * This is the data the caller needs
	 */
	*size_needed = byte_stream_size_needed;

	return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_rs_calculate_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  AE_OK if okay, else a valid ACPI_STATUS code
 *
 * 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_calculate_list_length (
	u8                      *byte_stream_buffer,
	u32                     byte_stream_buffer_length,
	u32                     *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;


	while (bytes_parsed < byte_stream_buffer_length) {
		/*
		 * Look at the next byte in the stream
		 */
		resource_type = *byte_stream_buffer;

		/*
		 * See if this is a small or large resource
		 */
		if(resource_type & 0x80) {
			/*
			 * Large Resource Type
			 */
			switch (resource_type)
			{
			case MEMORY_RANGE_24:
				/*
				 * 24-Bit Memory Resource
				 */
				bytes_consumed = 12;

				structure_size = sizeof (MEMORY24_RESOURCE) +
						  RESOURCE_LENGTH_NO_DATA;
				break;

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

				MOVE_UNALIGNED16_TO_16 (&temp16, buffer);
				bytes_consumed = temp16 + 3;

				/*
				 * Ensure a 32-bit boundary for the structure
				 */
				temp16 = (u16) ROUND_UP_TO_32_bITS (temp16);

				structure_size = sizeof (VENDOR_RESOURCE) +
						  RESOURCE_LENGTH_NO_DATA +
						  (temp16 * sizeof (u8));
				break;

			case MEMORY_RANGE_32:
				/*
				 * 32-Bit Memory Range Resource
				 */

				bytes_consumed = 20;

				structure_size = sizeof (MEMORY32_RESOURCE) +
						  RESOURCE_LENGTH_NO_DATA;
				break;

			case FIXED_MEMORY_RANGE_32:
				/*
				 * 32-Bit Fixed Memory Resource
				 */
				bytes_consumed = 12;

				structure_size = sizeof(FIXED_MEMORY32_RESOURCE) +
						  RESOURCE_LENGTH_NO_DATA;
				break;

			case DWORD_ADDRESS_SPACE:
				/*
				 * 32-Bit Address Resource
				 */
				buffer = byte_stream_buffer;

				++buffer;
				MOVE_UNALIGNED16_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 23, that
				 *  means that an Index exists and is followed by
				 *  a null termininated 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 terminiated string.
				 */
				if (23 < temp16) {
					temp8 = (u8) (temp16 - 24);
				}
				else {
					temp8 = 0;
				}

				/*
				 * Ensure a 32-bit boundary for the structure
				 */
				temp8 = (u8) ROUND_UP_TO_32_bITS (temp8);

				structure_size = sizeof (ADDRESS32_RESOURCE) +
						  RESOURCE_LENGTH_NO_DATA +
						  (temp8 * sizeof (u8));
				break;

			case WORD_ADDRESS_SPACE:
				/*
				 * 16-Bit Address Resource
				 */