rscalc.c

Go to the documentation of this file.

/*******************************************************************************
 *
 * Module Name: rscalc - Calculate stream and list lengths
 *
 ******************************************************************************/

/*
 * 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 "acresrc.h"
#include "acnamesp.h"

#define _COMPONENT          ACPI_RESOURCES
ACPI_MODULE_NAME("rscalc")

/* Local prototypes */
static u8 acpi_rs_count_set_bits(u16 bit_field);

static acpi_rs_length
acpi_rs_struct_option_length(struct acpi_resource_source *resource_source);

static u32
acpi_rs_stream_option_length(u32 resource_length, u32 minimum_total_length);

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_count_set_bits
 *
 * PARAMETERS:  bit_field       - Field in which to count bits
 *
 * RETURN:      Number of bits set within the field
 *
 * DESCRIPTION: Count the number of bits set in a resource field. Used for
 *              (Short descriptor) interrupt and DMA lists.
 *
 ******************************************************************************/

static u8 acpi_rs_count_set_bits(u16 bit_field)
{
    u8 bits_set;

    ACPI_FUNCTION_ENTRY();

    for (bits_set = 0; bit_field; bits_set++) {

        /* Zero the least significant bit that is set */

        bit_field &= (u16) (bit_field - 1);
    }

    return bits_set;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_struct_option_length
 *
 * PARAMETERS:  resource_source     - Pointer to optional descriptor field
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Common code to handle optional resource_source_index and
 *              resource_source fields in some Large descriptors. Used during
 *              list-to-stream conversion
 *
 ******************************************************************************/

static acpi_rs_length
acpi_rs_struct_option_length(struct acpi_resource_source *resource_source)
{
    ACPI_FUNCTION_ENTRY();

    /*
     * If the resource_source string is valid, return the size of the string
     * (string_length includes the NULL terminator) plus the size of the
     * resource_source_index (1).
     */
    if (resource_source->string_ptr) {
        return ((acpi_rs_length) (resource_source->string_length + 1));
    }

    return (0);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_stream_option_length
 *
 * PARAMETERS:  resource_length     - Length from the resource header
 *              minimum_total_length - Minimum length of this resource, before
 *                                    any optional fields. Includes header size
 *
 * RETURN:      Length of optional string (0 if no string present)
 *
 * DESCRIPTION: Common code to handle optional resource_source_index and
 *              resource_source fields in some Large descriptors. Used during
 *              stream-to-list conversion
 *
 ******************************************************************************/

static u32
acpi_rs_stream_option_length(u32 resource_length,
                 u32 minimum_aml_resource_length)
{
    u32 string_length = 0;

    ACPI_FUNCTION_ENTRY();

    /*
     * The resource_source_index and resource_source are optional elements of some
     * Large-type resource descriptors.
     */

    /*
     * If the length of the actual resource descriptor is greater than the ACPI
     * spec-defined minimum length, it means that a resource_source_index exists
     * and is followed by a (required) null terminated string. The string length
     * (including the null terminator) is the resource length minus the minimum
     * length, minus one byte for the resource_source_index itself.
     */
    if (resource_length > minimum_aml_resource_length) {

        /* Compute the length of the optional string */

        string_length =
            resource_length - minimum_aml_resource_length - 1;
    }

    /*
     * Round the length up to a multiple of the native word in order to
     * guarantee that the entire resource descriptor is native word aligned
     */
    return ((u32) ACPI_ROUND_UP_TO_NATIVE_WORD(string_length));
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_aml_length
 *
 * PARAMETERS:  resource            - Pointer to the resource linked list
 *              size_needed         - Where the required size is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes a linked list of internal resource descriptors and
 *              calculates the size buffer needed to hold the corresponding
 *              external resource byte stream.
 *
 ******************************************************************************/

acpi_status
acpi_rs_get_aml_length(struct acpi_resource * resource, acpi_size * size_needed)
{
    acpi_size aml_size_needed = 0;
    acpi_rs_length total_size;

    ACPI_FUNCTION_TRACE(rs_get_aml_length);

    /* Traverse entire list of internal resource descriptors */

    while (resource) {

        /* Validate the descriptor type */

        if (resource->type > ACPI_RESOURCE_TYPE_MAX) {
            return_ACPI_STATUS(AE_AML_INVALID_RESOURCE_TYPE);
        }

        /* Get the base size of the (external stream) resource descriptor */

        total_size = acpi_gbl_aml_resource_sizes[resource->type];

        /*
         * Augment the base size for descriptors with optional and/or
         * variable-length fields
         */
        switch (resource->type) {
        case ACPI_RESOURCE_TYPE_IRQ:

            /* Length can be 3 or 2 */

            if (resource->data.irq.descriptor_length == 2) {
                total_size--;
            }
            break;

        case ACPI_RESOURCE_TYPE_START_DEPENDENT:

            /* Length can be 1 or 0 */

            if (resource->data.irq.descriptor_length == 0) {
                total_size--;
            }
            break;

        case ACPI_RESOURCE_TYPE_VENDOR:
            /*
             * 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 (resource->data.vendor.byte_length > 7) {

                /* Base size of a Large resource descriptor */

                total_size =
                    sizeof(struct aml_resource_large_header);
            }

            /* Add the size of the vendor-specific data */

            total_size = (acpi_rs_length)
                (total_size + resource->data.vendor.byte_length);
            break;

        case ACPI_RESOURCE_TYPE_END_TAG:
            /*
             * End Tag:
             * We are done -- return the accumulated total size.
             */
            *size_needed = aml_size_needed + total_size;

            /* Normal exit */

            return_ACPI_STATUS(AE_OK);

        case ACPI_RESOURCE_TYPE_ADDRESS16:
            /*
             * 16-Bit Address Resource:
             * Add the size of the optional resource_source info
             */
            total_size = (acpi_rs_length)
                (total_size +
                 acpi_rs_struct_option_length(&resource->data.
                              address16.
                              resource_source));
            break;

        case ACPI_RESOURCE_TYPE_ADDRESS32:
            /*
             * 32-Bit Address Resource:
             * Add the size of the optional resource_source info
             */
            total_size = (acpi_rs_length)
                (total_size +
                 acpi_rs_struct_option_length(&resource->data.
                              address32.
                              resource_source));
            break;

        case ACPI_RESOURCE_TYPE_ADDRESS64:
            /*
             * 64-Bit Address Resource:
             * Add the size of the optional resource_source info
             */
            total_size = (acpi_rs_length)
                (total_size +
                 acpi_rs_struct_option_length(&resource->data.
                              address64.
                              resource_source));
            break;

        case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
            /*
             * Extended IRQ Resource:
             * Add the size of each additional optional interrupt beyond the
             * required 1 (4 bytes for each u32 interrupt number)
             */
            total_size = (acpi_rs_length)
                (total_size +
                 ((resource->data.extended_irq.interrupt_count -
                   1) * 4) +
                 /* Add the size of the optional resource_source info */
                 acpi_rs_struct_option_length(&resource->data.
                              extended_irq.
                              resource_source));
            break;

        case ACPI_RESOURCE_TYPE_GPIO:

            total_size =
                (acpi_rs_length) (total_size +
                          (resource->data.gpio.
                           pin_table_length * 2) +
                          resource->data.gpio.
                          resource_source.string_length +
                          resource->data.gpio.
                          vendor_length);

            break;

        case ACPI_RESOURCE_TYPE_SERIAL_BUS:

            total_size =
                acpi_gbl_aml_resource_serial_bus_sizes[resource->
                                   data.
                                   common_serial_bus.
                                   type];

            total_size = (acpi_rs_length) (total_size +
                               resource->data.
                               i2c_serial_bus.
                               resource_source.
                               string_length +
                               resource->data.
                               i2c_serial_bus.
                               vendor_length);

            break;

        default:
            break;
        }

        /* Update the total */

        aml_size_needed += total_size;

        /* Point to the next object */

        resource =
            ACPI_ADD_PTR(struct acpi_resource, resource,
                 resource->length);
    }

    /* Did not find an end_tag resource descriptor */

    return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_list_length
 *
 * PARAMETERS:  aml_buffer          - Pointer to the resource byte stream
 *              aml_buffer_length   - Size of aml_buffer
 *              size_needed         - Where the size needed is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Takes an external resource byte stream and calculates the size
 *              buffer needed to hold the corresponding internal resource
 *              descriptor linked list.
 *
 ******************************************************************************/

acpi_status
acpi_rs_get_list_length(u8 * aml_buffer,
            u32 aml_buffer_length, acpi_size * size_needed)
{
    acpi_status status;
    u8 *end_aml;
    u8 *buffer;
    u32 buffer_size;
    u16 temp16;
    u16 resource_length;
    u32 extra_struct_bytes;
    u8 resource_index;
    u8 minimum_aml_resource_length;
    union aml_resource *aml_resource;

    ACPI_FUNCTION_TRACE(rs_get_list_length);

    *size_needed = ACPI_RS_SIZE_MIN;    /* Minimum size is one end_tag */
    end_aml = aml_buffer + aml_buffer_length;

    /* Walk the list of AML resource descriptors */

    while (aml_buffer < end_aml) {

        /* Validate the Resource Type and Resource Length */

        status = acpi_ut_validate_resource(aml_buffer, &resource_index);
        if (ACPI_FAILURE(status)) {
            /*
             * Exit on failure. Cannot continue because the descriptor length
             * may be bogus also.
             */
            return_ACPI_STATUS(status);
        }

        aml_resource = (void *)aml_buffer;

        /* Get the resource length and base (minimum) AML size */

        resource_length = acpi_ut_get_resource_length(aml_buffer);
        minimum_aml_resource_length =
            acpi_gbl_resource_aml_sizes[resource_index];

        /*
         * Augment the size for descriptors with optional
         * and/or variable length fields
         */
        extra_struct_bytes = 0;
        buffer =
            aml_buffer + acpi_ut_get_resource_header_length(aml_buffer);

        switch (acpi_ut_get_resource_type(aml_buffer)) {
        case ACPI_RESOURCE_NAME_IRQ:
            /*
             * IRQ Resource:
             * Get the number of bits set in the 16-bit IRQ mask
             */
            ACPI_MOVE_16_TO_16(&temp16, buffer);
            extra_struct_bytes = acpi_rs_count_set_bits(temp16);
            break;

        case ACPI_RESOURCE_NAME_DMA:
            /*
             * DMA Resource:
             * Get the number of bits set in the 8-bit DMA mask
             */
            extra_struct_bytes = acpi_rs_count_set_bits(*buffer);
            break;

        case ACPI_RESOURCE_NAME_VENDOR_SMALL:
        case ACPI_RESOURCE_NAME_VENDOR_LARGE:
            /*
             * Vendor Resource:
             * Get the number of vendor data bytes
             */
            extra_struct_bytes = resource_length;
            break;

        case ACPI_RESOURCE_NAME_END_TAG:
            /*
             * End Tag: This is the normal exit
             */
            return_ACPI_STATUS(AE_OK);

        case ACPI_RESOURCE_NAME_ADDRESS32:
        case ACPI_RESOURCE_NAME_ADDRESS16:
        case ACPI_RESOURCE_NAME_ADDRESS64:
            /*
             * Address Resource:
             * Add the size of the optional resource_source
             */
            extra_struct_bytes =
                acpi_rs_stream_option_length(resource_length,
                             minimum_aml_resource_length);
            break;

        case ACPI_RESOURCE_NAME_EXTENDED_IRQ:
            /*
             * Extended IRQ Resource:
             * Using the interrupt_table_length, add 4 bytes for each additional
             * interrupt. Note: at least one interrupt is required and is
             * included in the minimum descriptor size (reason for the -1)
             */
            extra_struct_bytes = (buffer[1] - 1) * sizeof(u32);

            /* Add the size of the optional resource_source */

            extra_struct_bytes +=
                acpi_rs_stream_option_length(resource_length -
                             extra_struct_bytes,
                             minimum_aml_resource_length);
            break;

        case ACPI_RESOURCE_NAME_GPIO:

            /* Vendor data is optional */

            if (aml_resource->gpio.vendor_length) {
                extra_struct_bytes +=
                    aml_resource->gpio.vendor_offset -
                    aml_resource->gpio.pin_table_offset +
                    aml_resource->gpio.vendor_length;
            } else {
                extra_struct_bytes +=
                    aml_resource->large_header.resource_length +
                    sizeof(struct aml_resource_large_header) -
                    aml_resource->gpio.pin_table_offset;
            }
            break;

        case ACPI_RESOURCE_NAME_SERIAL_BUS:

            minimum_aml_resource_length =
                acpi_gbl_resource_aml_serial_bus_sizes
                [aml_resource->common_serial_bus.type];
            extra_struct_bytes +=
                aml_resource->common_serial_bus.resource_length -
                minimum_aml_resource_length;
            break;

        default:
            break;
        }

        /*
         * Update the required buffer size for the internal descriptor structs
         *
         * Important: Round the size up for the appropriate alignment. This
         * is a requirement on IA64.
         */
        if (acpi_ut_get_resource_type(aml_buffer) ==
            ACPI_RESOURCE_NAME_SERIAL_BUS) {
            buffer_size =
                acpi_gbl_resource_struct_serial_bus_sizes
                [aml_resource->common_serial_bus.type] +
                extra_struct_bytes;
        } else {
            buffer_size =
                acpi_gbl_resource_struct_sizes[resource_index] +
                extra_struct_bytes;
        }
        buffer_size = (u32)ACPI_ROUND_UP_TO_NATIVE_WORD(buffer_size);

        *size_needed += buffer_size;

        ACPI_DEBUG_PRINT((ACPI_DB_RESOURCES,
                  "Type %.2X, AmlLength %.2X InternalLength %.2X\n",
                  acpi_ut_get_resource_type(aml_buffer),
                  acpi_ut_get_descriptor_length(aml_buffer),
                  buffer_size));

        /*
         * Point to the next resource within the AML stream using the length
         * contained in the resource descriptor header
         */
        aml_buffer += acpi_ut_get_descriptor_length(aml_buffer);
    }

    /* Did not find an end_tag resource descriptor */

    return_ACPI_STATUS(AE_AML_NO_RESOURCE_END_TAG);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_rs_get_pci_routing_table_length
 *
 * PARAMETERS:  package_object          - Pointer to the package object
 *              buffer_size_needed      - u32 pointer of the size buffer
 *                                        needed to properly return the
 *                                        parsed data
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Given a package representing a PCI routing table, this
 *              calculates the size of the corresponding linked list of
 *              descriptions.
 *
 ******************************************************************************/

acpi_status
acpi_rs_get_pci_routing_table_length(union acpi_operand_object *package_object,
                     acpi_size * buffer_size_needed)
{
    u32 number_of_elements;
    acpi_size temp_size_needed = 0;
    union acpi_operand_object **top_object_list;
    u32 index;
    union acpi_operand_object *package_element;
    union acpi_operand_object **sub_object_list;
    u8 name_found;
    u32 table_index;

    ACPI_FUNCTION_TRACE(rs_get_pci_routing_table_length);

    number_of_elements = package_object->package.count;

    /*
     * Calculate the size of the return buffer.
     * The base size is the number of elements * the sizes of the
     * structures.  Additional space for the strings is added below.
     * The minus one is to subtract the size of the u8 Source[1]
     * member because it is added below.
     *
     * But each PRT_ENTRY structure has a pointer to a string and
     * the size of that string must be found.
     */
    top_object_list = package_object->package.elements;

    for (index = 0; index < number_of_elements; index++) {

        /* Dereference the sub-package */

        package_element = *top_object_list;

        /* We must have a valid Package object */

        if (!package_element ||
            (package_element->common.type != ACPI_TYPE_PACKAGE)) {
            return_ACPI_STATUS(AE_AML_OPERAND_TYPE);
        }

        /*
         * The sub_object_list will now point to an array of the
         * four IRQ elements: Address, Pin, Source and source_index
         */
        sub_object_list = package_element->package.elements;

        /* Scan the irq_table_elements for the Source Name String */

        name_found = FALSE;

        for (table_index = 0; table_index < 4 && !name_found;
             table_index++) {
            if (*sub_object_list && /* Null object allowed */
                ((ACPI_TYPE_STRING ==
                  (*sub_object_list)->common.type) ||
                 ((ACPI_TYPE_LOCAL_REFERENCE ==
                   (*sub_object_list)->common.type) &&
                  ((*sub_object_list)->reference.class ==
                   ACPI_REFCLASS_NAME)))) {
                name_found = TRUE;
            } else {
                /* Look at the next element */

                sub_object_list++;
            }
        }

        temp_size_needed += (sizeof(struct acpi_pci_routing_table) - 4);

        /* Was a String type found? */

        if (name_found) {
            if ((*sub_object_list)->common.type == ACPI_TYPE_STRING) {
                /*
                 * The length String.Length field does not include the
                 * terminating NULL, add 1
                 */
                temp_size_needed += ((acpi_size)
                             (*sub_object_list)->string.
                             length + 1);
            } else {
                temp_size_needed +=
                    acpi_ns_get_pathname_length((*sub_object_list)->reference.node);
            }
        } else {
            /*
             * If no name was found, then this is a NULL, which is
             * translated as a u32 zero.
             */
            temp_size_needed += sizeof(u32);
        }

        /* Round up the size since each element must be aligned */

        temp_size_needed = ACPI_ROUND_UP_TO_64BIT(temp_size_needed);

        /* Point to the next union acpi_operand_object */

        top_object_list++;
    }

    /*
     * Add an extra element to the end of the list, essentially a
     * NULL terminator
     */
    *buffer_size_needed =
        temp_size_needed + sizeof(struct acpi_pci_routing_table);
    return_ACPI_STATUS(AE_OK);
}