tbget.c

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/******************************************************************************
 *
 * Module Name: tbget - ACPI Table get* routines
 *              $Revision: 1.1 $
 *
 *****************************************************************************/

/*
 *  Copyright (C) 2000, 2001 R. Byron Moore
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include <acpi.h>

#define _COMPONENT          ACPI_TABLES
     MODULE_NAME         ("tbget")

#define RSDP_CHECKSUM_LENGTH 20

/*******************************************************************************
 *
 * FUNCTION:    Acpi_tb_get_table_ptr
 *
 * PARAMETERS:  Table_type      - one of the defined table types
 *              Instance        - Which table of this type
 *              Table_ptr_loc   - pointer to location to place the pointer for
 *                                return
 *
 * RETURN:      Status
 *
 * DESCRIPTION: This function is called to get the pointer to an ACPI table.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_tb_get_table_ptr (
    ACPI_TABLE_TYPE         table_type,
    u32                     instance,
    ACPI_TABLE_HEADER       **table_ptr_loc)
{
    ACPI_TABLE_DESC         *table_desc;
    u32                     i;


    if (!acpi_gbl_DSDT) {
        return (AE_NO_ACPI_TABLES);
    }

    if (table_type > ACPI_TABLE_MAX) {
        return (AE_BAD_PARAMETER);
    }


    /*
     * For all table types (Single/Multiple), the first
     * instance is always in the list head.
     */

    if (instance == 1) {
        /*
         * Just pluck the pointer out of the global table!
         * Will be null if no table is present
         */

        *table_ptr_loc = acpi_gbl_acpi_tables[table_type].pointer;
        return (AE_OK);
    }


    /*
     * Check for instance out of range
     */
    if (instance > acpi_gbl_acpi_tables[table_type].count) {
        return (AE_NOT_EXIST);
    }

    /* Walk the list to get the desired table
     *  Since the if (Instance == 1) check above checked for the
     *  first table, setting Table_desc equal to the .Next member
     *  is actually pointing to the second table.  Therefore, we
     *  need to walk from the 2nd table until we reach the Instance
     *  that the user is looking for and return its table pointer.
     */
    table_desc = acpi_gbl_acpi_tables[table_type].next;
    for (i = 2; i < instance; i++) {
        table_desc = table_desc->next;
    }

    /* We are now pointing to the requested table's descriptor */

    *table_ptr_loc = table_desc->pointer;

    return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_tb_get_table
 *
 * PARAMETERS:  Physical_address        - Physical address of table to retrieve
 *              *Buffer_ptr             - If Buffer_ptr is valid, read data from
 *                                         buffer rather than searching memory
 *              *Table_info             - Where the table info is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Maps the physical address of table into a logical address
 *
 ******************************************************************************/

ACPI_STATUS
acpi_tb_get_table (
    ACPI_PHYSICAL_ADDRESS   physical_address,
    ACPI_TABLE_HEADER       *buffer_ptr,
    ACPI_TABLE_DESC         *table_info)
{
    ACPI_TABLE_HEADER       *table_header = NULL;
    ACPI_TABLE_HEADER       *full_table = NULL;
    u32                     size;
    u8                      allocation;
    ACPI_STATUS             status = AE_OK;


    if (!table_info) {
        return (AE_BAD_PARAMETER);
    }


    if (buffer_ptr) {
        /*
         * Getting data from a buffer, not BIOS tables
         */

        table_header = buffer_ptr;
        status = acpi_tb_validate_table_header (table_header);
        if (ACPI_FAILURE (status)) {
            /* Table failed verification, map all errors to BAD_DATA */

            return (AE_BAD_DATA);
        }

        /* Allocate buffer for the entire table */

        full_table = acpi_cm_allocate (table_header->length);
        if (!full_table) {
            return (AE_NO_MEMORY);
        }

        /* Copy the entire table (including header) to the local buffer */

        size = table_header->length;
        MEMCPY (full_table, buffer_ptr, size);

        /* Save allocation type */

        allocation = ACPI_MEM_ALLOCATED;
    }


    /*
     * Not reading from a buffer, just map the table's physical memory
     * into our address space.
     */
    else {
        size = SIZE_IN_HEADER;

        status = acpi_tb_map_acpi_table (physical_address, &size,
                  (void **) &full_table);
        if (ACPI_FAILURE (status)) {
            return (status);
        }

        /* Save allocation type */

        allocation = ACPI_MEM_MAPPED;
    }


    /* Return values */

    table_info->pointer     = full_table;
    table_info->length      = size;
    table_info->allocation  = allocation;
    table_info->base_pointer = full_table;

    return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_tb_get_all_tables
 *
 * PARAMETERS:  Number_of_tables    - Number of tables to get
 *              Table_ptr           - Input buffer pointer, optional
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load and validate all tables other than the RSDT.  The RSDT must
 *              already be loaded and validated.
 *
 ******************************************************************************/

ACPI_STATUS
acpi_tb_get_all_tables (
    u32                     number_of_tables,
    ACPI_TABLE_HEADER       *table_ptr)
{
    ACPI_STATUS             status = AE_OK;
    u32                     index;
    ACPI_TABLE_DESC         table_info;


    /*
     * Loop through all table pointers found in RSDT.
     * This will NOT include the FACS and DSDT - we must get
     * them after the loop
     */

    for (index = 0; index < number_of_tables; index++) {
        /* Clear the Table_info each time */

        MEMSET (&table_info, 0, sizeof (ACPI_TABLE_DESC));

        /* Get the table via the XSDT */

        status = acpi_tb_get_table ((ACPI_PHYSICAL_ADDRESS)
                 ACPI_GET_ADDRESS (acpi_gbl_XSDT->table_offset_entry[index]),
                 table_ptr, &table_info);

        /* Ignore a table that failed verification */

        if (status == AE_BAD_DATA) {
            continue;
        }

        /* However, abort on serious errors */

        if (ACPI_FAILURE (status)) {
            return (status);
        }

        /* Recognize and install the table */

        status = acpi_tb_install_table (table_ptr, &table_info);
        if (ACPI_FAILURE (status)) {
            /*
             * Unrecognized or unsupported table, delete it and ignore the
             * error.  Just get as many tables as we can, later we will
             * determine if there are enough tables to continue.
             */

            acpi_tb_uninstall_table (&table_info);
        }
    }


    /*
     * Convert the FADT to a common format.  This allows earlier revisions of the
     * table to coexist with newer versions, using common access code.
     */
    status = acpi_tb_convert_table_fadt ();
    if (ACPI_FAILURE (status)) {
        return (status);
    }


    /*
     * Get the minimum set of ACPI tables, namely:
     *
     * 1) FADT (via RSDT in loop above)
     * 2) FACS
     * 3) DSDT
     *
     */


    /*
     * Get the FACS (must have the FADT first, from loop above)
     * Acpi_tb_get_table_facs will fail if FADT pointer is not valid
     */

    status = acpi_tb_get_table_facs (table_ptr, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }


    /* Install the FACS */

    status = acpi_tb_install_table (table_ptr, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    /*
     * Create the common FACS pointer table
     * (Contains pointers to the original table)
     */

    status = acpi_tb_build_common_facs (&table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }


    /*
     * Get the DSDT (We know that the FADT is valid now)
     */

    status = acpi_tb_get_table ((ACPI_PHYSICAL_ADDRESS) ACPI_GET_ADDRESS (acpi_gbl_FADT->Xdsdt),
              table_ptr, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    /* Install the DSDT */

    status = acpi_tb_install_table (table_ptr, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    /* Dump the DSDT Header */

    /* Dump the entire DSDT */

    /*
     * Initialize the capabilities flags.
     * Assumes that platform supports ACPI_MODE since we have tables!
     */
    acpi_gbl_system_flags |= acpi_hw_get_mode_capabilities ();


    /* Always delete the RSDP mapping, we are done with it */

    acpi_tb_delete_acpi_table (ACPI_TABLE_RSDP);

    return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_tb_verify_rsdp
 *
 * PARAMETERS:  Number_of_tables    - Where the table count is placed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load and validate the RSDP (ptr) and RSDT (table)
 *
 ******************************************************************************/

ACPI_STATUS
acpi_tb_verify_rsdp (
    ACPI_PHYSICAL_ADDRESS   rsdp_physical_address)
{
    ACPI_TABLE_DESC         table_info;
    ACPI_STATUS             status;
    u8                      *table_ptr;


    /*
     * Obtain access to the RSDP structure
     */
    status = acpi_os_map_memory (rsdp_physical_address,
              sizeof (RSDP_DESCRIPTOR),
              (void **) &table_ptr);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    /*
     *  The signature and checksum must both be correct
     */
    if (STRNCMP ((NATIVE_CHAR *) table_ptr, RSDP_SIG, sizeof (RSDP_SIG)-1) != 0) {
        /* Nope, BAD Signature */

        status = AE_BAD_SIGNATURE;
        goto cleanup;
    }

    if (acpi_tb_checksum (table_ptr, RSDP_CHECKSUM_LENGTH) != 0) {
        /* Nope, BAD Checksum */

        status = AE_BAD_CHECKSUM;
        goto cleanup;
    }

    /* TBD: Check extended checksum if table version >= 2 */

    /* The RSDP supplied is OK */

    table_info.pointer     = (ACPI_TABLE_HEADER *) table_ptr;
    table_info.length      = sizeof (RSDP_DESCRIPTOR);
    table_info.allocation  = ACPI_MEM_MAPPED;
    table_info.base_pointer = table_ptr;

    /* Save the table pointers and allocation info */

    status = acpi_tb_init_table_descriptor (ACPI_TABLE_RSDP, &table_info);
    if (ACPI_FAILURE (status)) {
        goto cleanup;
    }


    /* Save the RSDP in a global for easy access */

    acpi_gbl_RSDP = (RSDP_DESCRIPTOR *) table_info.pointer;
    return (status);


    /* Error exit */
cleanup:

    acpi_os_unmap_memory (table_ptr, sizeof (RSDP_DESCRIPTOR));
    return (status);
}


/*******************************************************************************
 *
 * FUNCTION:    Acpi_tb_get_table_rsdt
 *
 * PARAMETERS:  Number_of_tables    - Where the table count is placed
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Load and validate the RSDP (ptr) and RSDT (table)
 *
 ******************************************************************************/

ACPI_STATUS
acpi_tb_get_table_rsdt (
    u32                     *number_of_tables)
{
    ACPI_TABLE_DESC         table_info;
    ACPI_STATUS             status = AE_OK;
    ACPI_PHYSICAL_ADDRESS   physical_address;
    u32                     signature_length;
    char                    *table_signature;


    /*
     * Get the RSDT from the RSDP
     */

    /*
     * For RSDP revision 0 or 1, we use the RSDT.
     * For RSDP revision 2 (and above), we use the XSDT
     */
    if (acpi_gbl_RSDP->revision < 2) {
#ifdef _IA64
        /* 0.71 RSDP has 64bit Rsdt address field */
        physical_address = ((RSDP_DESCRIPTOR_REV071 *)acpi_gbl_RSDP)->rsdt_physical_address;
#else
        physical_address = (ACPI_PHYSICAL_ADDRESS) acpi_gbl_RSDP->rsdt_physical_address;
#endif
        table_signature = RSDT_SIG;
        signature_length = sizeof (RSDT_SIG) -1;
    }
    else {
        physical_address = (ACPI_PHYSICAL_ADDRESS)
                   ACPI_GET_ADDRESS (acpi_gbl_RSDP->xsdt_physical_address);
        table_signature = XSDT_SIG;
        signature_length = sizeof (XSDT_SIG) -1;
    }


    /* Get the RSDT/XSDT */

    status = acpi_tb_get_table (physical_address, NULL, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }


    /* Check the RSDT or XSDT signature */

    if (STRNCMP ((char *) table_info.pointer, table_signature,
              signature_length)) {
        /* Invalid RSDT or XSDT signature */

        REPORT_ERROR (("Invalid signature where RSDP indicates %s should be located\n",
                  table_signature));

        return (AE_NO_ACPI_TABLES);
    }


    /* Valid RSDT signature, verify the checksum */

    status = acpi_tb_verify_table_checksum (table_info.pointer);


    /* Convert and/or copy to an XSDT structure */

    status = acpi_tb_convert_to_xsdt (&table_info, number_of_tables);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    /* Save the table pointers and allocation info */

    status = acpi_tb_init_table_descriptor (ACPI_TABLE_XSDT, &table_info);
    if (ACPI_FAILURE (status)) {
        return (status);
    }

    acpi_gbl_XSDT = (XSDT_DESCRIPTOR *) table_info.pointer;

    return (status);
}


/******************************************************************************
 *
 * FUNCTION:    Acpi_tb_get_table_facs
 *
 * PARAMETERS:  *Buffer_ptr             - If Buffer_ptr is valid, read data from
 *                                          buffer rather than searching memory
 *              *Table_info             - Where the table info is returned
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Returns a pointer to the FACS as defined in FADT.  This
 *              function assumes the global variable FADT has been
 *              correctly initialized.  The value of FADT->Firmware_ctrl
 *              into a far pointer which is returned.
 *
 *****************************************************************************/

ACPI_STATUS
acpi_tb_get_table_facs (
    ACPI_TABLE_HEADER       *buffer_ptr,
    ACPI_TABLE_DESC         *table_info)
{
    void                    *table_ptr = NULL;
    u32                     size;
    u8                      allocation;
    ACPI_STATUS             status = AE_OK;


    /* Must have a valid FADT pointer */

    if (!acpi_gbl_FADT) {
        return (AE_NO_ACPI_TABLES);
    }

    size = sizeof (FACS_DESCRIPTOR);
    if (buffer_ptr) {
        /*
         * Getting table from a file -- allocate a buffer and
         * read the table.
         */
        table_ptr = acpi_cm_allocate (size);
        if(!table_ptr) {
            return (AE_NO_MEMORY);
        }

        MEMCPY (table_ptr, buffer_ptr, size);

        /* Save allocation type */

        allocation = ACPI_MEM_ALLOCATED;
    }

    else {
        /* Just map the physical memory to our address space */

        status = acpi_tb_map_acpi_table ((ACPI_PHYSICAL_ADDRESS) ACPI_GET_ADDRESS (acpi_gbl_FADT->Xfirmware_ctrl),
                   &size, &table_ptr);
        if (ACPI_FAILURE(status)) {
            return (status);
        }

        /* Save allocation type */

        allocation = ACPI_MEM_MAPPED;
    }


    /* Return values */

    table_info->pointer     = table_ptr;
    table_info->length      = size;
    table_info->allocation  = allocation;
    table_info->base_pointer = table_ptr;

    return (status);
}