exmisc.c

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

/*
 * Copyright (C) 2000 - 2012, 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"
#include "amlresrc.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, "Unknown Reference Class 0x%2.2X",
                    obj_desc->reference.class));
            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_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_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)
{
    acpi_status status;
    union acpi_operand_object *return_desc;
    u8 *new_buf;
    u8 *end_tag;
    acpi_size length0;
    acpi_size length1;
    acpi_size new_length;

    ACPI_FUNCTION_TRACE(ex_concat_template);

    /*
     * Find the end_tag descriptor in each resource template.
     * Note1: returned pointers point TO the end_tag, not past it.
     * Note2: zero-length buffers are allowed; treated like one end_tag
     */

    /* Get the length of the first resource template */

    status = acpi_ut_get_resource_end_tag(operand0, &end_tag);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    length0 = ACPI_PTR_DIFF(end_tag, operand0->buffer.pointer);

    /* Get the length of the second resource template */

    status = acpi_ut_get_resource_end_tag(operand1, &end_tag);
    if (ACPI_FAILURE(status)) {
        return_ACPI_STATUS(status);
    }

    length1 = ACPI_PTR_DIFF(end_tag, operand1->buffer.pointer);

    /* Combine both lengths, minimum size will be 2 for end_tag */

    new_length = length0 + length1 + sizeof(struct aml_resource_end_tag);

    /* Create a new buffer object for the result (with one end_tag) */

    return_desc = acpi_ut_create_buffer_object(new_length);
    if (!return_desc) {
        return_ACPI_STATUS(AE_NO_MEMORY);
    }

    /*
     * Copy the templates to the new buffer, 0 first, then 1 follows. One
     * end_tag descriptor is copied from Operand1.
     */
    new_buf = return_desc->buffer.pointer;
    ACPI_MEMCPY(new_buf, operand0->buffer.pointer, length0);
    ACPI_MEMCPY(new_buf + length0, operand1->buffer.pointer, length1);

    /* Insert end_tag and set the checksum to zero, means "ignore checksum" */

    new_buf[new_length - 1] = 0;
    new_buf[new_length - 2] = ACPI_RESOURCE_NAME_END_TAG | 1;

    /* Return the completed resource template */

    *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_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 (operand0->common.type) {
    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_ERROR((AE_INFO, "Invalid object type: 0x%X",
                operand0->common.type));
        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 (operand0->common.type) {
    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_size)
                               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 */

        return_desc = acpi_ut_create_string_object(((acpi_size)
                                operand0->string.
                                length +
                                local_operand1->
                                string.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 +
                                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_ERROR((AE_INFO, "Invalid object type: 0x%X",
                operand0->common.type));
        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.
 *
 ******************************************************************************/

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, 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 (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 = ACPI_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);
}