drivers/acpi/executer/exmisc.c

/******************************************************************************
 *
 * Module Name: exmisc - ACPI AML (p-code) execution - specific opcodes
 *
 *****************************************************************************/

/*
 * 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/acinterp.h>
#include <acpi/amlcode.h>


#define _COMPONENT          ACPI_EXECUTER
	 ACPI_MODULE_NAME    ("exmisc")


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_get_object_reference
 *
 * PARAMETERS:  obj_desc            - Create a reference to this object
 *              return_desc         - Where to store the reference
 *              walk_state          - Current state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Obtain and return a "reference" to the target object
 *              Common code for the ref_of_op and the cond_ref_of_op.
 *
 ******************************************************************************/

acpi_status
acpi_ex_get_object_reference (
	union acpi_operand_object       *obj_desc,
	union acpi_operand_object       **return_desc,
	struct acpi_walk_state          *walk_state)
{
	union acpi_operand_object       *reference_obj;
	union acpi_operand_object       *referenced_obj;


	ACPI_FUNCTION_TRACE_PTR ("ex_get_object_reference", obj_desc);


	*return_desc = NULL;

	switch (ACPI_GET_DESCRIPTOR_TYPE (obj_desc)) {
	case ACPI_DESC_TYPE_OPERAND:

		if (ACPI_GET_OBJECT_TYPE (obj_desc) != ACPI_TYPE_LOCAL_REFERENCE) {
			return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
		}

		/*
		 * Must be a reference to a Local or Arg
		 */
		switch (obj_desc->reference.opcode) {
		case AML_LOCAL_OP:
		case AML_ARG_OP:
		case AML_DEBUG_OP:

			/* The referenced object is the pseudo-node for the local/arg */

			referenced_obj = obj_desc->reference.object;
			break;

		default:

			ACPI_REPORT_ERROR (("Unknown Reference opcode in get_reference %X\n",
				obj_desc->reference.opcode));
			return_ACPI_STATUS (AE_AML_INTERNAL);
		}
		break;


	case ACPI_DESC_TYPE_NAMED:

		/*
		 * A named reference that has already been resolved to a Node
		 */
		referenced_obj = obj_desc;
		break;


	default:

		ACPI_REPORT_ERROR (("Invalid descriptor type in get_reference: %X\n",
				ACPI_GET_DESCRIPTOR_TYPE (obj_desc)));
		return_ACPI_STATUS (AE_TYPE);
	}


	/* Create a new reference object */

	reference_obj = acpi_ut_create_internal_object (ACPI_TYPE_LOCAL_REFERENCE);
	if (!reference_obj) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	reference_obj->reference.opcode = AML_REF_OF_OP;
	reference_obj->reference.object = referenced_obj;
	*return_desc = reference_obj;

	ACPI_DEBUG_PRINT ((ACPI_DB_EXEC,
		"Object %p Type [%s], returning Reference %p\n",
		obj_desc, acpi_ut_get_object_type_name (obj_desc), *return_desc));

	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_concat_template
 *
 * PARAMETERS:  Operand0            - First source object
 *              Operand1            - Second source object
 *              actual_return_desc  - Where to place the return object
 *              walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Concatenate two resource templates
 *
 ******************************************************************************/

acpi_status
acpi_ex_concat_template (
	union acpi_operand_object       *operand0,
	union acpi_operand_object       *operand1,
	union acpi_operand_object       **actual_return_desc,
	struct acpi_walk_state          *walk_state)
{
	union acpi_operand_object       *return_desc;
	u8                              *new_buf;
	u8                              *end_tag1;
	u8                              *end_tag2;
	acpi_size                       length1;
	acpi_size                       length2;


	ACPI_FUNCTION_TRACE ("ex_concat_template");


	/* Find the end_tags in each resource template */

	end_tag1 = acpi_ut_get_resource_end_tag (operand0);
	end_tag2 = acpi_ut_get_resource_end_tag (operand1);
	if (!end_tag1 || !end_tag2) {
		return_ACPI_STATUS (AE_AML_OPERAND_TYPE);
	}

	/* Compute the length of each part */

	length1 = ACPI_PTR_DIFF (end_tag1, operand0->buffer.pointer);
	length2 = ACPI_PTR_DIFF (end_tag2, operand1->buffer.pointer) +
			  2; /* Size of END_TAG */

	/* Create a new buffer object for the result */

	return_desc = acpi_ut_create_buffer_object (length1 + length2);
	if (!return_desc) {
		return_ACPI_STATUS (AE_NO_MEMORY);
	}

	/* Copy the templates to the new descriptor */

	new_buf = return_desc->buffer.pointer;
	ACPI_MEMCPY (new_buf, operand0->buffer.pointer, length1);
	ACPI_MEMCPY (new_buf + length1, operand1->buffer.pointer, length2);

	/* Compute the new checksum */

	new_buf[return_desc->buffer.length - 1] =
			acpi_ut_generate_checksum (return_desc->buffer.pointer,
					   (return_desc->buffer.length - 1));

	/* Return the completed template descriptor */

	*actual_return_desc = return_desc;
	return_ACPI_STATUS (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_do_concatenate
 *
 * PARAMETERS:  Operand0            - First source object
 *              Operand1            - Second source object
 *              actual_return_desc  - Where to place the return object
 *              walk_state          - Current walk state
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Concatenate two objects OF THE SAME TYPE.
 *
 ******************************************************************************/

acpi_status
acpi_ex_do_concatenate (
	union acpi_operand_object       *operand0,
	union acpi_operand_object       *operand1,
	union acpi_operand_object       **actual_return_desc,
	struct acpi_walk_state          *walk_state)
{
	union acpi_operand_object       *local_operand1 = operand1;
	union acpi_operand_object       *return_desc;
	char                            *new_buf;
	acpi_status                     status;
	acpi_size                       new_length;


	ACPI_FUNCTION_TRACE ("ex_do_concatenate");


	/*
	 * Convert the second operand if necessary.  The first operand
	 * determines the type of the second operand, (See the Data Types
	 * section of the ACPI specification.)  Both object types are
	 * guaranteed to be either Integer/String/Buffer by the operand
	 * resolution mechanism.
	 */
	switch (ACPI_GET_OBJECT_TYPE (operand0)) {
	case ACPI_TYPE_INTEGER:
		status = acpi_ex_convert_to_integer (operand1, &local_operand1, 16);
		break;

	case ACPI_TYPE_STRING:
		status = acpi_ex_convert_to_string (operand1, &local_operand1,
				 ACPI_IMPLICIT_CONVERT_HEX);
		break;

	case ACPI_TYPE_BUFFER:
		status = acpi_ex_convert_to_buffer (operand1, &local_operand1);
		break;

	default:
		ACPI_REPORT_ERROR (("Concat - invalid obj type: %X\n",
				ACPI_GET_OBJECT_TYPE (operand0)));
		status = AE_AML_INTERNAL;
	}

	if (ACPI_FAILURE (status)) {
		goto cleanup;
	}

	/*
	 * Both operands are now known to be the same object type
	 * (Both are Integer, String, or Buffer), and we can now perform the
	 * concatenation.
	 */

	/*
	 * There are three cases to handle:
	 *
	 * 1) Two Integers concatenated to produce a new Buffer
	 * 2) Two Strings concatenated to produce a new String
	 * 3) Two Buffers concatenated to produce a new Buffer
	 */
	switch (ACPI_GET_OBJECT_TYPE (operand0)) {
	case ACPI_TYPE_INTEGER:

		/* Result of two Integers is a Buffer */
		/* Need enough buffer space for two integers */

		return_desc = acpi_ut_create_buffer_object (
				   ACPI_MUL_2 (acpi_gbl_integer_byte_width));
		if (!return_desc) {
			status = AE_NO_MEMORY;
			goto cleanup;
		}

		new_buf = (char *) return_desc->buffer.pointer;

		/* Copy the first integer, LSB first */

		ACPI_MEMCPY (new_buf,
				  &operand0->integer.value,
				  acpi_gbl_integer_byte_width);

		/* Copy the second integer (LSB first) after the first */

		ACPI_MEMCPY (new_buf + acpi_gbl_integer_byte_width,
				  &local_operand1->integer.value,
				  acpi_gbl_integer_byte_width);
		break;

	case ACPI_TYPE_STRING:

		/* Result of two Strings is a String */

		new_length = (acpi_size) operand0->string.length +
				 (acpi_size) local_operand1->string.length;
		if (new_length > ACPI_MAX_STRING_CONVERSION) {
			status = AE_AML_STRING_LIMIT;
			goto cleanup;
		}

		return_desc = acpi_ut_create_string_object (new_length);
		if (!return_desc) {
			status = AE_NO_MEMORY;
			goto cleanup;
		}

		new_buf = return_desc->string.pointer;

		/* Concatenate the strings */

		ACPI_STRCPY (new_buf,
				  operand0->string.pointer);
		ACPI_STRCPY (new_buf + operand0->string.length,
				  local_operand1->string.pointer);
		break;

	case ACPI_TYPE_BUFFER:

		/* Result of two Buffers is a Buffer */

		return_desc = acpi_ut_create_buffer_object (
				   (acpi_size) operand0->buffer.length +
				   (acpi_size) local_operand1->buffer.length);
		if (!return_desc) {
			status = AE_NO_MEMORY;
			goto cleanup;
		}

		new_buf = (char *) return_desc->buffer.pointer;

		/* Concatenate the buffers */

		ACPI_MEMCPY (new_buf,
				  operand0->buffer.pointer,
				  operand0->buffer.length);
		ACPI_MEMCPY (new_buf + operand0->buffer.length,
				  local_operand1->buffer.pointer,
				  local_operand1->buffer.length);
		break;

	default:

		/* Invalid object type, should not happen here */

		ACPI_REPORT_ERROR (("Concatenate - Invalid object type: %X\n",
				ACPI_GET_OBJECT_TYPE (operand0)));
		status =AE_AML_INTERNAL;
		goto cleanup;
	}

	*actual_return_desc = return_desc;

cleanup:
	if (local_operand1 != operand1) {
		acpi_ut_remove_reference (local_operand1);
	}
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_do_math_op
 *
 * PARAMETERS:  Opcode              - AML opcode
 *              Integer0            - Integer operand #0
 *              Integer1            - Integer operand #1
 *
 * RETURN:      Integer result of the operation
 *
 * DESCRIPTION: Execute a math AML opcode. The purpose of having all of the
 *              math functions here is to prevent a lot of pointer dereferencing
 *              to obtain the operands.
 *
 ******************************************************************************/

acpi_integer
acpi_ex_do_math_op (
	u16                             opcode,
	acpi_integer                    integer0,
	acpi_integer                    integer1)
{

	ACPI_FUNCTION_ENTRY ();


	switch (opcode) {
	case AML_ADD_OP:                /* Add (Integer0, Integer1, Result) */

		return (integer0 + integer1);


	case AML_BIT_AND_OP:            /* And (Integer0, Integer1, Result) */

		return (integer0 & integer1);


	case AML_BIT_NAND_OP:           /* NAnd (Integer0, Integer1, Result) */

		return (~(integer0 & integer1));


	case AML_BIT_OR_OP:             /* Or (Integer0, Integer1, Result) */

		return (integer0 | integer1);


	case AML_BIT_NOR_OP:            /* NOr (Integer0, Integer1, Result) */

		return (~(integer0 | integer1));


	case AML_BIT_XOR_OP:            /* XOr (Integer0, Integer1, Result) */

		return (integer0 ^ integer1);


	case AML_MULTIPLY_OP:           /* Multiply (Integer0, Integer1, Result) */

		return (integer0 * integer1);


	case AML_SHIFT_LEFT_OP:         /* shift_left (Operand, shift_count, Result)*/

		return (integer0 << integer1);


	case AML_SHIFT_RIGHT_OP:        /* shift_right (Operand, shift_count, Result) */

		return (integer0 >> integer1);


	case AML_SUBTRACT_OP:           /* Subtract (Integer0, Integer1, Result) */

		return (integer0 - integer1);

	default:

		return (0);
	}
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_do_logical_numeric_op
 *
 * PARAMETERS:  Opcode              - AML opcode
 *              Integer0            - Integer operand #0
 *              Integer1            - Integer operand #1
 *              logical_result      - TRUE/FALSE result of the operation
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute a logical "Numeric" AML opcode. For these Numeric
 *              operators (LAnd and LOr), both operands must be integers.
 *
 *              Note: cleanest machine code seems to be produced by the code
 *              below, rather than using statements of the form:
 *                  Result = (Integer0 && Integer1);
 *
 ******************************************************************************/

acpi_status
acpi_ex_do_logical_numeric_op (
	u16                             opcode,
	acpi_integer                    integer0,
	acpi_integer                    integer1,
	u8                              *logical_result)
{
	acpi_status                     status = AE_OK;
	u8                              local_result = FALSE;


	ACPI_FUNCTION_TRACE ("ex_do_logical_numeric_op");


	switch (opcode) {
	case AML_LAND_OP:               /* LAnd (Integer0, Integer1) */

		if (integer0 && integer1) {
			local_result = TRUE;
		}
		break;

	case AML_LOR_OP:                /* LOr (Integer0, Integer1) */

		if (integer0 || integer1) {
			local_result = TRUE;
		}
		break;

	default:
		status = AE_AML_INTERNAL;
		break;
	}

	/* Return the logical result and status */

	*logical_result = local_result;
	return_ACPI_STATUS (status);
}


/*******************************************************************************
 *
 * FUNCTION:    acpi_ex_do_logical_op
 *
 * PARAMETERS:  Opcode              - AML opcode
 *              Operand0            - operand #0
 *              Operand1            - operand #1
 *              logical_result      - TRUE/FALSE result of the operation
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Execute a logical AML opcode. The purpose of having all of the
 *              functions here is to prevent a lot of pointer dereferencing
 *              to obtain the operands and to simplify the generation of the
 *              logical value. For the Numeric operators (LAnd and LOr), both
 *              operands must be integers. For the other logical operators,
 *              operands can be any combination of Integer/String/Buffer. The
 *              first operand determines the type to which the second operand
 *              will be converted.
 *
 *              Note: cleanest machine code seems to be produced by the code
 *              below, rather than using statements of the form:
 *                  Result = (Operand0 == Operand1);
 *
 ******************************************************************************/

acpi_status
acpi_ex_do_logical_op (
	u16                             opcode,
	union acpi_operand_object       *operand0,
	union acpi_operand_object       *operand1,
	u8                              *logical_result)
{
	union acpi_operand_object       *local_operand1 = operand1;
	acpi_integer                    integer0;
	acpi_integer                    integer1;
	u32                             length0;
	u32                             length1;
	acpi_status                     status = AE_OK;
	u8                              local_result = FALSE;
	int                             compare;


	ACPI_FUNCTION_TRACE ("ex_do_logical_op");


	/*
	 * Convert the second operand if necessary.  The first operand
	 * determines the type of the second operand, (See the Data Types
	 * section of the ACPI 3.0+ specification.)  Both object types are
	 * guaranteed to be either Integer/String/Buffer by the operand
	 * resolution mechanism.
	 */
	switch (ACPI_GET_OBJECT_TYPE (operand0)) {
	case ACPI_TYPE_INTEGER:
		status = acpi_ex_convert_to_integer (operand1, &local_operand1, 16);
		break;

	case ACPI_TYPE_STRING:
		status = acpi_ex_convert_to_string (operand1, &local_operand1,
				 ACPI_IMPLICIT_CONVERT_HEX);
		break;

	case ACPI_TYPE_BUFFER:
		status = acpi_ex_convert_to_buffer (operand1, &local_operand1);
		break;

	default:
		status = AE_AML_INTERNAL;
		break;
	}

	if (ACPI_FAILURE (status)) {
		goto cleanup;
	}

	/*
	 * Two cases: 1) Both Integers, 2) Both Strings or Buffers
	 */
	if (ACPI_GET_OBJECT_TYPE (operand0) == ACPI_TYPE_INTEGER) {
		/*
		 * 1) Both operands are of type integer
		 *    Note: local_operand1 may have changed above
		 */
		integer0 = operand0->integer.value;
		integer1 = local_operand1->integer.value;

		switch (opcode) {
		case AML_LEQUAL_OP:             /* LEqual (Operand0, Operand1) */

			if (integer0 == integer1) {
				local_result = TRUE;
			}
			break;

		case AML_LGREATER_OP:           /* LGreater (Operand0, Operand1) */

			if (integer0 > integer1) {
				local_result = TRUE;
			}
			break;

		case AML_LLESS_OP:              /* LLess (Operand0, Operand1) */

			if (integer0 < integer1) {
				local_result = TRUE;
			}
			break;

		default:
			status = AE_AML_INTERNAL;
			break;
		}
	}
	else {
		/*
		 * 2) Both operands are Strings or both are Buffers
		 *    Note: Code below takes advantage of common Buffer/String
		 *          object fields. local_operand1 may have changed above. Use
		 *          memcmp to handle nulls in buffers.
		 */
		length0 = operand0->buffer.length;
		length1 = local_operand1->buffer.length;

		/* Lexicographic compare: compare the data bytes */

		compare = ACPI_MEMCMP ((const char * ) operand0->buffer.pointer,
				 (const char * ) local_operand1->buffer.pointer,
				 (length0 > length1) ? length1 : length0);

		switch (opcode) {
		case AML_LEQUAL_OP:             /* LEqual (Operand0, Operand1) */

			/* Length and all bytes must be equal */

			if ((length0 == length1) &&
				(compare == 0)) {
				/* Length and all bytes match ==> TRUE */

				local_result = TRUE;
			}
			break;

		case AML_LGREATER_OP:           /* LGreater (Operand0, Operand1) */

			if (compare > 0) {
				local_result = TRUE;
				goto cleanup;   /* TRUE */
			}
			if (compare < 0) {
				goto cleanup;   /* FALSE */
			}

			/* Bytes match (to shortest length), compare lengths */

			if (length0 > length1) {
				local_result = TRUE;
			}
			break;

		case AML_LLESS_OP:              /* LLess (Operand0, Operand1) */

			if (compare > 0) {
				goto cleanup;   /* FALSE */
			}
			if (compare < 0) {
				local_result = TRUE;
				goto cleanup;   /* TRUE */
			}

			/* Bytes match (to shortest length), compare lengths */

			if (length0 < length1) {
				local_result = TRUE;
			}
			break;

		default:
			status = AE_AML_INTERNAL;
			break;
		}
	}

cleanup:

	/* New object was created if implicit conversion performed - delete */

	if (local_operand1 != operand1) {
		acpi_ut_remove_reference (local_operand1);
	}

	/* Return the logical result and status */

	*logical_result = local_result;
	return_ACPI_STATUS (status);
}