[mirror_ubuntu-artful-kernel.git] / drivers / acpi / acpica / exmisc.c

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

/*
 * Copyright (C) 2000 - 2017, 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 "acinterp.h"
#include "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 (obj_desc->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
		}

		/*
		 * Must be a reference to a Local or Arg
		 */
		switch (obj_desc->reference.class) {
		case ACPI_REFCLASS_LOCAL:
		case ACPI_REFCLASS_ARG:
		case ACPI_REFCLASS_DEBUG:

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

			referenced_obj = obj_desc->reference.object;
			break;

		default:

			ACPI_ERROR((AE_INFO, "Invalid Reference Class 0x%2.2X",
				    obj_desc->reference.class));
			return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
		}
		break;

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

	default:

		ACPI_ERROR((AE_INFO, "Invalid descriptor type 0x%X",
			    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.class = ACPI_REFCLASS_REFOF;
	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_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.
 *
 ******************************************************************************/

u64 acpi_ex_do_math_op(u16 opcode, u64 integer0, u64 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) */

		/*
		 * We need to check if the shiftcount is larger than the integer bit
		 * width since the behavior of this is not well-defined in the C language.
		 */
		if (integer1 >= acpi_gbl_integer_bit_width) {
			return (0);
		}
		return (integer0 << integer1);

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

		/*
		 * We need to check if the shiftcount is larger than the integer bit
		 * width since the behavior of this is not well-defined in the C language.
		 */
		if (integer1 >= acpi_gbl_integer_bit_width) {
			return (0);
		}
		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,
			      u64 integer0, u64 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;
	u64 integer0;
	u64 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 (operand0->common.type) {
	case ACPI_TYPE_INTEGER:

		status = acpi_ex_convert_to_integer(operand1, &local_operand1,
						    ACPI_STRTOUL_BASE16);
		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 (operand0->common.type == 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 = memcmp(operand0->buffer.pointer,
				 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);
}
Commit	Line	Data
1da177e4 LT	1	/******************************************************************************
	2	*
	3	* Module Name: exmisc - ACPI AML (p-code) execution - specific opcodes
	4	*
	5	*****************************************************************************/
	6
	7	/*
7735ca0e	8	* Copyright (C) 2000 - 2017, Intel Corp.
1da177e4 LT	9	* All rights reserved.
	10	*
	11	* Redistribution and use in source and binary forms, with or without
	12	* modification, are permitted provided that the following conditions
	13	* are met:
	14	* 1. Redistributions of source code must retain the above copyright
	15	* notice, this list of conditions, and the following disclaimer,
	16	* without modification.
	17	* 2. Redistributions in binary form must reproduce at minimum a disclaimer
	18	* substantially similar to the "NO WARRANTY" disclaimer below
	19	* ("Disclaimer") and any redistribution must be conditioned upon
	20	* including a substantially similar Disclaimer requirement for further
	21	* binary redistribution.
	22	* 3. Neither the names of the above-listed copyright holders nor the names
	23	* of any contributors may be used to endorse or promote products derived
	24	* from this software without specific prior written permission.
	25	*
	26	* Alternatively, this software may be distributed under the terms of the
	27	* GNU General Public License ("GPL") version 2 as published by the Free
	28	* Software Foundation.
	29	*
	30	* NO WARRANTY
	31	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	32	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	33	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
	34	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	35	* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	36	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	37	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	38	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	39	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
	40	* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	41	* POSSIBILITY OF SUCH DAMAGES.
	42	*/
	43
1da177e4	44	#include <acpi/acpi.h>
e2f7a777 LB	45	#include "accommon.h"
	46	#include "acinterp.h"
	47	#include "amlcode.h"
1da177e4	48
1da177e4	49	#define _COMPONENT ACPI_EXECUTER
4be44fcd	50	ACPI_MODULE_NAME("exmisc")
1da177e4 LT	51
	52	/*******************************************************************************
	53	*
	54	* FUNCTION: acpi_ex_get_object_reference
	55	*
	56	* PARAMETERS: obj_desc - Create a reference to this object
	57	* return_desc - Where to store the reference
	58	* walk_state - Current state
	59	*
	60	* RETURN: Status
	61	*
	62	* DESCRIPTION: Obtain and return a "reference" to the target object
	63	* Common code for the ref_of_op and the cond_ref_of_op.
	64	*
	65	******************************************************************************/
1da177e4	66	acpi_status
4be44fcd LB	67	acpi_ex_get_object_reference(union acpi_operand_object *obj_desc,
	68	union acpi_operand_object **return_desc,
	69	struct acpi_walk_state *walk_state)
1da177e4	70	{
4be44fcd LB	71	union acpi_operand_object *reference_obj;
4be44fcd LB	72	union acpi_operand_object *referenced_obj;
1da177e4	73
b229cf92	74	ACPI_FUNCTION_TRACE_PTR(ex_get_object_reference, obj_desc);
1da177e4 LT	75
	76	*return_desc = NULL;
	77
4be44fcd	78	switch (ACPI_GET_DESCRIPTOR_TYPE(obj_desc)) {
1da177e4 LT	79	case ACPI_DESC_TYPE_OPERAND:
1da177e4 LT	80
3371c19c	81	if (obj_desc->common.type != ACPI_TYPE_LOCAL_REFERENCE) {
4be44fcd	82	return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
1da177e4 LT	83	}
	84
	85	/*
	86	* Must be a reference to a Local or Arg
	87	*/
1044f1f6 BM	88	switch (obj_desc->reference.class) {
	89	case ACPI_REFCLASS_LOCAL:
	90	case ACPI_REFCLASS_ARG:
	91	case ACPI_REFCLASS_DEBUG:
1da177e4 LT	92
	93	/* The referenced object is the pseudo-node for the local/arg */
	94
	95	referenced_obj = obj_desc->reference.object;
	96	break;
	97
	98	default:
	99
395ec731	100	ACPI_ERROR((AE_INFO, "Invalid Reference Class 0x%2.2X",
1044f1f6	101	obj_desc->reference.class));
395ec731	102	return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
1da177e4 LT	103	}
	104	break;
	105
1da177e4	106	case ACPI_DESC_TYPE_NAMED:
1da177e4 LT	107	/*
	108	* A named reference that has already been resolved to a Node
	109	*/
	110	referenced_obj = obj_desc;
	111	break;
	112
1da177e4 LT	113	default:
1da177e4 LT	114
f6a22b0b	115	ACPI_ERROR((AE_INFO, "Invalid descriptor type 0x%X",
b8e4d893	116	ACPI_GET_DESCRIPTOR_TYPE(obj_desc)));
4be44fcd	117	return_ACPI_STATUS(AE_TYPE);
1da177e4 LT	118	}
1da177e4 LT	119
1da177e4 LT	120	/* Create a new reference object */
1da177e4 LT	121
4be44fcd LB	122	reference_obj =
4be44fcd LB	123	acpi_ut_create_internal_object(ACPI_TYPE_LOCAL_REFERENCE);
1da177e4	124	if (!reference_obj) {
4be44fcd	125	return_ACPI_STATUS(AE_NO_MEMORY);
1da177e4 LT	126	}
1da177e4 LT	127
1044f1f6	128	reference_obj->reference.class = ACPI_REFCLASS_REFOF;
1da177e4 LT	129	reference_obj->reference.object = referenced_obj;
	130	*return_desc = reference_obj;
	131
4be44fcd LB	132	ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
	133	"Object %p Type [%s], returning Reference %p\n",
	134	obj_desc, acpi_ut_get_object_type_name(obj_desc),
	135	*return_desc));
1da177e4	136
4be44fcd	137	return_ACPI_STATUS(AE_OK);
1da177e4 LT	138	}
1da177e4 LT	139
1da177e4 LT	140	/*******************************************************************************
	141	*
	142	* FUNCTION: acpi_ex_do_math_op
	143	*
ba494bee BM	144	* PARAMETERS: opcode - AML opcode
	145	* integer0 - Integer operand #0
	146	* integer1 - Integer operand #1
1da177e4 LT	147	*
	148	* RETURN: Integer result of the operation
	149	*
	150	* DESCRIPTION: Execute a math AML opcode. The purpose of having all of the
	151	* math functions here is to prevent a lot of pointer dereferencing
	152	* to obtain the operands.
	153	*
	154	******************************************************************************/
	155
5df7e6cb	156	u64 acpi_ex_do_math_op(u16 opcode, u64 integer0, u64 integer1)
1da177e4 LT	157	{
1da177e4 LT	158
4be44fcd	159	ACPI_FUNCTION_ENTRY();
1da177e4 LT	160
1da177e4 LT	161	switch (opcode) {
4be44fcd	162	case AML_ADD_OP: /* Add (Integer0, Integer1, Result) */
1da177e4 LT	163
	164	return (integer0 + integer1);
	165
4be44fcd	166	case AML_BIT_AND_OP: /* And (Integer0, Integer1, Result) */
1da177e4 LT	167
	168	return (integer0 & integer1);
	169
4be44fcd	170	case AML_BIT_NAND_OP: /* NAnd (Integer0, Integer1, Result) */
1da177e4 LT	171
	172	return (~(integer0 & integer1));
	173
4be44fcd	174	case AML_BIT_OR_OP: /* Or (Integer0, Integer1, Result) */
1da177e4 LT	175
	176	return (integer0 \| integer1);
	177
4be44fcd	178	case AML_BIT_NOR_OP: /* NOr (Integer0, Integer1, Result) */
1da177e4 LT	179
	180	return (~(integer0 \| integer1));
	181
4be44fcd	182	case AML_BIT_XOR_OP: /* XOr (Integer0, Integer1, Result) */
1da177e4 LT	183
	184	return (integer0 ^ integer1);
	185
4be44fcd	186	case AML_MULTIPLY_OP: /* Multiply (Integer0, Integer1, Result) */
1da177e4 LT	187
	188	return (integer0 * integer1);
	189
4be44fcd	190	case AML_SHIFT_LEFT_OP: /* shift_left (Operand, shift_count, Result) */
1da177e4	191
4119532c BM	192	/*
	193	* We need to check if the shiftcount is larger than the integer bit
	194	* width since the behavior of this is not well-defined in the C language.
	195	*/
	196	if (integer1 >= acpi_gbl_integer_bit_width) {
	197	return (0);
	198	}
1da177e4 LT	199	return (integer0 << integer1);
1da177e4 LT	200
4be44fcd	201	case AML_SHIFT_RIGHT_OP: /* shift_right (Operand, shift_count, Result) */
1da177e4	202
4119532c BM	203	/*
	204	* We need to check if the shiftcount is larger than the integer bit
	205	* width since the behavior of this is not well-defined in the C language.
	206	*/
	207	if (integer1 >= acpi_gbl_integer_bit_width) {
	208	return (0);
	209	}
1da177e4 LT	210	return (integer0 >> integer1);
1da177e4 LT	211
4be44fcd	212	case AML_SUBTRACT_OP: /* Subtract (Integer0, Integer1, Result) */
1da177e4 LT	213
	214	return (integer0 - integer1);
	215
	216	default:
	217
	218	return (0);
	219	}
	220	}
	221
1da177e4 LT	222	/*******************************************************************************
	223	*
	224	* FUNCTION: acpi_ex_do_logical_numeric_op
	225	*
ba494bee BM	226	* PARAMETERS: opcode - AML opcode
	227	* integer0 - Integer operand #0
	228	* integer1 - Integer operand #1
1da177e4 LT	229	* logical_result - TRUE/FALSE result of the operation
	230	*
	231	* RETURN: Status
	232	*
	233	* DESCRIPTION: Execute a logical "Numeric" AML opcode. For these Numeric
	234	* operators (LAnd and LOr), both operands must be integers.
	235	*
	236	* Note: cleanest machine code seems to be produced by the code
	237	* below, rather than using statements of the form:
	238	* Result = (Integer0 && Integer1);
	239	*
	240	******************************************************************************/
	241
	242	acpi_status
4be44fcd	243	acpi_ex_do_logical_numeric_op(u16 opcode,
5df7e6cb	244	u64 integer0, u64 integer1, u8 *logical_result)
1da177e4	245	{
4be44fcd LB	246	acpi_status status = AE_OK;
4be44fcd LB	247	u8 local_result = FALSE;
1da177e4	248
b229cf92	249	ACPI_FUNCTION_TRACE(ex_do_logical_numeric_op);
1da177e4 LT	250
1da177e4 LT	251	switch (opcode) {
4be44fcd	252	case AML_LAND_OP: /* LAnd (Integer0, Integer1) */
1da177e4 LT	253
	254	if (integer0 && integer1) {
	255	local_result = TRUE;
	256	}
	257	break;
	258
4be44fcd	259	case AML_LOR_OP: /* LOr (Integer0, Integer1) */
1da177e4 LT	260
	261	if (integer0 \|\| integer1) {
	262	local_result = TRUE;
	263	}
	264	break;
	265
	266	default:
1d1ea1b7	267
1da177e4 LT	268	status = AE_AML_INTERNAL;
	269	break;
	270	}
	271
	272	/* Return the logical result and status */
	273
	274	*logical_result = local_result;
4be44fcd	275	return_ACPI_STATUS(status);
1da177e4 LT	276	}
1da177e4 LT	277
1da177e4 LT	278	/*******************************************************************************
	279	*
	280	* FUNCTION: acpi_ex_do_logical_op
	281	*
ba494bee BM	282	* PARAMETERS: opcode - AML opcode
	283	* operand0 - operand #0
	284	* operand1 - operand #1
1da177e4 LT	285	* logical_result - TRUE/FALSE result of the operation
	286	*
	287	* RETURN: Status
	288	*
	289	* DESCRIPTION: Execute a logical AML opcode. The purpose of having all of the
	290	* functions here is to prevent a lot of pointer dereferencing
	291	* to obtain the operands and to simplify the generation of the
	292	* logical value. For the Numeric operators (LAnd and LOr), both
	293	* operands must be integers. For the other logical operators,
	294	* operands can be any combination of Integer/String/Buffer. The
	295	* first operand determines the type to which the second operand
	296	* will be converted.
	297	*
	298	* Note: cleanest machine code seems to be produced by the code
	299	* below, rather than using statements of the form:
	300	* Result = (Operand0 == Operand1);
	301	*
	302	******************************************************************************/
	303
	304	acpi_status
4be44fcd LB	305	acpi_ex_do_logical_op(u16 opcode,
	306	union acpi_operand_object *operand0,
	307	union acpi_operand_object operand1, u8 logical_result)
1da177e4	308	{
4be44fcd	309	union acpi_operand_object *local_operand1 = operand1;
5df7e6cb BM	310	u64 integer0;
5df7e6cb BM	311	u64 integer1;
4be44fcd LB	312	u32 length0;
	313	u32 length1;
	314	acpi_status status = AE_OK;
	315	u8 local_result = FALSE;
	316	int compare;
1da177e4	317
b229cf92	318	ACPI_FUNCTION_TRACE(ex_do_logical_op);
1da177e4 LT	319
1da177e4 LT	320	/*
73a3090a	321	* Convert the second operand if necessary. The first operand
1da177e4 LT	322	* determines the type of the second operand, (See the Data Types
	323	* section of the ACPI 3.0+ specification.) Both object types are
	324	* guaranteed to be either Integer/String/Buffer by the operand
	325	* resolution mechanism.
	326	*/
3371c19c	327	switch (operand0->common.type) {
1da177e4	328	case ACPI_TYPE_INTEGER:
1d1ea1b7	329
5ebd2eaa BM	330	status = acpi_ex_convert_to_integer(operand1, &local_operand1,
5ebd2eaa BM	331	ACPI_STRTOUL_BASE16);
1da177e4 LT	332	break;
	333
	334	case ACPI_TYPE_STRING:
1d1ea1b7	335
1fad8738 BM	336	status =
	337	acpi_ex_convert_to_string(operand1, &local_operand1,
	338	ACPI_IMPLICIT_CONVERT_HEX);
1da177e4 LT	339	break;
	340
	341	case ACPI_TYPE_BUFFER:
1d1ea1b7	342
4be44fcd	343	status = acpi_ex_convert_to_buffer(operand1, &local_operand1);
1da177e4 LT	344	break;
	345
	346	default:
1d1ea1b7	347
1da177e4 LT	348	status = AE_AML_INTERNAL;
	349	break;
	350	}
	351
4be44fcd	352	if (ACPI_FAILURE(status)) {
1da177e4 LT	353	goto cleanup;
	354	}
	355
	356	/*
	357	* Two cases: 1) Both Integers, 2) Both Strings or Buffers
	358	*/
3371c19c	359	if (operand0->common.type == ACPI_TYPE_INTEGER) {
1da177e4 LT	360	/*
	361	* 1) Both operands are of type integer
	362	* Note: local_operand1 may have changed above
	363	*/
	364	integer0 = operand0->integer.value;
	365	integer1 = local_operand1->integer.value;
	366
	367	switch (opcode) {
4be44fcd	368	case AML_LEQUAL_OP: /* LEqual (Operand0, Operand1) */
1da177e4 LT	369
	370	if (integer0 == integer1) {
	371	local_result = TRUE;
	372	}
	373	break;
	374
4be44fcd	375	case AML_LGREATER_OP: /* LGreater (Operand0, Operand1) */
1da177e4 LT	376
	377	if (integer0 > integer1) {
	378	local_result = TRUE;
	379	}
	380	break;
	381
4be44fcd	382	case AML_LLESS_OP: /* LLess (Operand0, Operand1) */
1da177e4 LT	383
	384	if (integer0 < integer1) {
	385	local_result = TRUE;
	386	}
	387	break;
	388
	389	default:
1d1ea1b7	390
1da177e4 LT	391	status = AE_AML_INTERNAL;
	392	break;
	393	}
4be44fcd	394	} else {
1da177e4 LT	395	/*
	396	* 2) Both operands are Strings or both are Buffers
	397	* Note: Code below takes advantage of common Buffer/String
	398	* object fields. local_operand1 may have changed above. Use
	399	* memcmp to handle nulls in buffers.
	400	*/
	401	length0 = operand0->buffer.length;
	402	length1 = local_operand1->buffer.length;
	403
	404	/* Lexicographic compare: compare the data bytes */
	405
4fa4616e BM	406	compare = memcmp(operand0->buffer.pointer,
	407	local_operand1->buffer.pointer,
	408	(length0 > length1) ? length1 : length0);
1da177e4 LT	409
1da177e4 LT	410	switch (opcode) {
4be44fcd	411	case AML_LEQUAL_OP: /* LEqual (Operand0, Operand1) */
1da177e4 LT	412
	413	/* Length and all bytes must be equal */
	414
4be44fcd	415	if ((length0 == length1) && (compare == 0)) {
52fc0b02	416
1da177e4 LT	417	/* Length and all bytes match ==> TRUE */
	418
	419	local_result = TRUE;
	420	}
	421	break;
	422
4be44fcd	423	case AML_LGREATER_OP: /* LGreater (Operand0, Operand1) */
1da177e4 LT	424
	425	if (compare > 0) {
	426	local_result = TRUE;
4be44fcd	427	goto cleanup; /* TRUE */
1da177e4 LT	428	}
1da177e4 LT	429	if (compare < 0) {
4be44fcd	430	goto cleanup; /* FALSE */
1da177e4 LT	431	}
	432
	433	/* Bytes match (to shortest length), compare lengths */
	434
	435	if (length0 > length1) {
	436	local_result = TRUE;
	437	}
	438	break;
	439
4be44fcd	440	case AML_LLESS_OP: /* LLess (Operand0, Operand1) */
1da177e4 LT	441
1da177e4 LT	442	if (compare > 0) {
4be44fcd	443	goto cleanup; /* FALSE */
1da177e4 LT	444	}
	445	if (compare < 0) {
	446	local_result = TRUE;
4be44fcd	447	goto cleanup; /* TRUE */
1da177e4 LT	448	}
	449
	450	/* Bytes match (to shortest length), compare lengths */
	451
	452	if (length0 < length1) {
	453	local_result = TRUE;
	454	}
	455	break;
	456
	457	default:
1d1ea1b7	458
1da177e4 LT	459	status = AE_AML_INTERNAL;
	460	break;
	461	}
	462	}
	463
10622bf8	464	cleanup:
1da177e4 LT	465
	466	/* New object was created if implicit conversion performed - delete */
	467
	468	if (local_operand1 != operand1) {
4be44fcd	469	acpi_ut_remove_reference(local_operand1);
1da177e4 LT	470	}
	471
	472	/* Return the logical result and status */
	473
	474	*logical_result = local_result;
4be44fcd	475	return_ACPI_STATUS(status);
1da177e4	476	}