rsutils.c

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/*******************************************************************************
 *
 * Module Name: rsutils - Utilities for the resource manager
 *
 ******************************************************************************/

/*
 * Copyright (C) 2000 - 2006, 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/acnamesp.h>
#include <acpi/acresrc.h>

#define _COMPONENT          ACPI_RESOURCES
ACPI_MODULE_NAME("rsutils")

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_decode_bitmask
 *
 * PARAMETERS:  Mask            - Bitmask to decode
 *              List            - Where the converted list is returned
 *
 * RETURN:      Count of bits set (length of list)
 *
 * DESCRIPTION: Convert a bit mask into a list of values
 *
 ******************************************************************************/
u8 acpi_rs_decode_bitmask(u16 mask, u8 * list)
{
	acpi_native_uint i;
	u8 bit_count;

	ACPI_FUNCTION_ENTRY();

	/* Decode the mask bits */

	for (i = 0, bit_count = 0; mask; i++) {
		if (mask & 0x0001) {
			list[bit_count] = (u8) i;
			bit_count++;
		}

		mask >>= 1;
	}

	return (bit_count);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_encode_bitmask
 *
 * PARAMETERS:  List            - List of values to encode
 *              Count           - Length of list
 *
 * RETURN:      Encoded bitmask
 *
 * DESCRIPTION: Convert a list of values to an encoded bitmask
 *
 ******************************************************************************/

u16 acpi_rs_encode_bitmask(u8 * list, u8 count)
{
	acpi_native_uint i;
	u16 mask;

	ACPI_FUNCTION_ENTRY();

	/* Encode the list into a single bitmask */

	for (i = 0, mask = 0; i < count; i++) {
		mask |= (0x0001 << list[i]);
	}

	return (mask);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_move_data
 *
 * PARAMETERS:  Destination         - Pointer to the destination descriptor
 *              Source              - Pointer to the source descriptor
 *              item_count          - How many items to move
 *              move_type           - Byte width
 *
 * RETURN:      None
 *
 * DESCRIPTION: Move multiple data items from one descriptor to another. Handles
 *              alignment issues and endian issues if necessary, as configured
 *              via the ACPI_MOVE_* macros. (This is why a memcpy is not used)
 *
 ******************************************************************************/

void
acpi_rs_move_data(void *destination, void *source, u16 item_count, u8 move_type)
{
	acpi_native_uint i;

	ACPI_FUNCTION_ENTRY();

	/* One move per item */

	for (i = 0; i < item_count; i++) {
		switch (move_type) {
			/*
			 * For the 8-bit case, we can perform the move all at once
			 * since there are no alignment or endian issues
			 */
		case ACPI_RSC_MOVE8:
			ACPI_MEMCPY(destination, source, item_count);
			return;

			/*
			 * 16-, 32-, and 64-bit cases must use the move macros that perform
			 * endian conversion and/or accomodate hardware that cannot perform
			 * misaligned memory transfers
			 */
		case ACPI_RSC_MOVE16:
			ACPI_MOVE_16_TO_16(&ACPI_CAST_PTR(u16, destination)[i],
					   &ACPI_CAST_PTR(u16, source)[i]);
			break;

		case ACPI_RSC_MOVE32:
			ACPI_MOVE_32_TO_32(&ACPI_CAST_PTR(u32, destination)[i],
					   &ACPI_CAST_PTR(u32, source)[i]);
			break;

		case ACPI_RSC_MOVE64:
			ACPI_MOVE_64_TO_64(&ACPI_CAST_PTR(u64, destination)[i],
					   &ACPI_CAST_PTR(u64, source)[i]);
			break;

		default:
			return;
		}
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_set_resource_length
 *
 * PARAMETERS:  total_length        - Length of the AML descriptor, including
 *                                    the header and length fields.
 *              Aml                 - Pointer to the raw AML descriptor
 *
 * RETURN:      None
 *
 * DESCRIPTION: Set the resource_length field of an AML
 *              resource descriptor, both Large and Small descriptors are
 *              supported automatically. Note: Descriptor Type field must
 *              be valid.
 *
 ******************************************************************************/

void
acpi_rs_set_resource_length(acpi_rsdesc_size total_length,
			    union aml_resource *aml)
{
	acpi_rs_length resource_length;

	ACPI_FUNCTION_ENTRY();

	/* Length is the total descriptor length minus the header length */

	resource_length = (acpi_rs_length)
	    (total_length - acpi_ut_get_resource_header_length(aml));

	/* Length is stored differently for large and small descriptors */

	if (aml->small_header.descriptor_type & ACPI_RESOURCE_NAME_LARGE) {
		/* Large descriptor -- bytes 1-2 contain the 16-bit length */

		ACPI_MOVE_16_TO_16(&aml->large_header.resource_length,
				   &resource_length);
	} else {
		/* Small descriptor -- bits 2:0 of byte 0 contain the length */

		aml->small_header.descriptor_type = (u8)

		    /* Clear any existing length, preserving descriptor type bits */
		    ((aml->small_header.
		      descriptor_type & ~ACPI_RESOURCE_NAME_SMALL_LENGTH_MASK)

		     | resource_length);
	}
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_set_resource_header
 *
 * PARAMETERS:  descriptor_type     - Byte to be inserted as the type
 *              total_length        - Length of the AML descriptor, including
 *                                    the header and length fields.
 *              Aml                 - Pointer to the raw AML descriptor
 *
 * RETURN:      None
 *
 * DESCRIPTION: Set the descriptor_type and resource_length fields of an AML
 *              resource descriptor, both Large and Small descriptors are
 *              supported automatically
 *
 ******************************************************************************/

void
acpi_rs_set_resource_header(u8 descriptor_type,
			    acpi_rsdesc_size total_length,
			    union aml_resource *aml)
{
	ACPI_FUNCTION_ENTRY();

	/* Set the Resource Type */

	aml->small_header.descriptor_type = descriptor_type;

	/* Set the Resource Length */

	acpi_rs_set_resource_length(total_length, aml);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_strcpy
 *
 * PARAMETERS:  Destination         - Pointer to the destination string
 *              Source              - Pointer to the source string
 *
 * RETURN:      String length, including NULL terminator
 *
 * DESCRIPTION: Local string copy that returns the string length, saving a
 *              strcpy followed by a strlen.
 *
 ******************************************************************************/

static u16 acpi_rs_strcpy(char *destination, char *source)
{
	u16 i;

	ACPI_FUNCTION_ENTRY();

	for (i = 0; source[i]; i++) {
		destination[i] = source[i];
	}

	destination[i] = 0;

	/* Return string length including the NULL terminator */

	return ((u16) (i + 1));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_resource_source
 *
 * PARAMETERS:  resource_length     - Length field of the descriptor
 *              minimum_length      - Minimum length of the descriptor (minus
 *                                    any optional fields)
 *              resource_source     - Where the resource_source is returned
 *              Aml                 - Pointer to the raw AML descriptor
 *              string_ptr          - (optional) where to store the actual
 *                                    resource_source string
 *
 * RETURN:      Length of the string plus NULL terminator, rounded up to 32 bit
 *
 * DESCRIPTION: Copy the optional resource_source data from a raw AML descriptor
 *              to an internal resource descriptor
 *
 ******************************************************************************/

acpi_rs_length
acpi_rs_get_resource_source(acpi_rs_length resource_length,
			    acpi_rs_length minimum_length,
			    struct acpi_resource_source * resource_source,
			    union aml_resource * aml, char *string_ptr)
{
	acpi_rsdesc_size total_length;
	u8 *aml_resource_source;

	ACPI_FUNCTION_ENTRY();

	total_length =
	    resource_length + sizeof(struct aml_resource_large_header);
	aml_resource_source = ACPI_ADD_PTR(u8, aml, minimum_length);

	/*
	 * resource_source is present if the length of the descriptor is longer than
	 * the minimum length.
	 *
	 * Note: Some resource descriptors will have an additional null, so
	 * we add 1 to the minimum length.
	 */
	if (total_length > (acpi_rsdesc_size) (minimum_length + 1)) {
		/* Get the resource_source_index */

		resource_source->index = aml_resource_source[0];

		resource_source->string_ptr = string_ptr;
		if (!string_ptr) {
			/*
			 * String destination pointer is not specified; Set the String
			 * pointer to the end of the current resource_source structure.
			 */
			resource_source->string_ptr =
			    ACPI_ADD_PTR(char, resource_source,
					 sizeof(struct acpi_resource_source));
		}

		/*
		 * In order for the struct_size to fall on a 32-bit boundary, calculate
		 * the length of the string (+1 for the NULL terminator) and expand the
		 * struct_size to the next 32-bit boundary.
		 *
		 * Zero the entire area of the buffer.
		 */
		total_length =
		    ACPI_ROUND_UP_to_32_bITS(ACPI_STRLEN
					     ((char *)&aml_resource_source[1]) +
					     1);