nsinit.c

acpi tools for linux include acpiexec and acpixtract

    case ACPI_TYPE_PACKAGE:
        Info->PackageCount++;
        break;

    default:

        /* No init required, just exit now */
        return (AE_OK);
    }

    /*
     * If the object is already initialized, nothing else to do
     */
    if (ObjDesc->Common.Flags & AOPOBJ_DATA_VALID)
    {
        return (AE_OK);
    }

    /*
     * Must lock the interpreter before executing AML code
     */
    AcpiExEnterInterpreter ();

    /*
     * Each of these types can contain executable AML code within the
     * declaration.
     */
    switch (Type)
    {
    case ACPI_TYPE_REGION:

        Info->OpRegionInit++;
        Status = AcpiDsGetRegionArguments (ObjDesc);
        break;

    case ACPI_TYPE_BUFFER_FIELD:

        Info->FieldInit++;
        Status = AcpiDsGetBufferFieldArguments (ObjDesc);
        break;

    case ACPI_TYPE_LOCAL_BANK_FIELD:

        Info->FieldInit++;
        Status = AcpiDsGetBankFieldArguments (ObjDesc);
        break;

    case ACPI_TYPE_BUFFER:

        Info->BufferInit++;
        Status = AcpiDsGetBufferArguments (ObjDesc);
        break;

    case ACPI_TYPE_PACKAGE:

        Info->PackageInit++;
        Status = AcpiDsGetPackageArguments (ObjDesc);
        break;

    default:
        /* No other types can get here */
        break;
    }

    if (ACPI_FAILURE (Status))
    {
        ACPI_EXCEPTION ((AE_INFO, Status,
            "Could not execute arguments for [%4.4s] (%s)",
            AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Type)));
    }

    /*
     * Print a dot for each object unless we are going to print the entire
     * pathname
     */
    if (!(AcpiDbgLevel & ACPI_LV_INIT_NAMES))
    {
        ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
    }

    /*
     * We ignore errors from above, and always return OK, since we don't want
     * to abort the walk on any single error.
     */
    AcpiExExitInterpreter ();
    return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiNsFindIniMethods
 *
 * PARAMETERS:  ACPI_WALK_CALLBACK
 *
 * RETURN:      ACPI_STATUS
 *
 * DESCRIPTION: Called during namespace walk. Finds objects named _INI under
 *              device/processor/thermal objects, and marks the entire subtree
 *              with a SUBTREE_HAS_INI flag. This flag is used during the
 *              subsequent device initialization walk to avoid entire subtrees
 *              that do not contain an _INI.
 *
 ******************************************************************************/

static ACPI_STATUS
AcpiNsFindIniMethods (
    ACPI_HANDLE             ObjHandle,
    UINT32                  NestingLevel,
    void                    *Context,
    void                    **ReturnValue)
{
    ACPI_DEVICE_WALK_INFO   *Info = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
    ACPI_NAMESPACE_NODE     *Node;
    ACPI_NAMESPACE_NODE     *ParentNode;


    /* Keep count of device/processor/thermal objects */

    Node = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
    if ((Node->Type == ACPI_TYPE_DEVICE)    ||
        (Node->Type == ACPI_TYPE_PROCESSOR) ||
        (Node->Type == ACPI_TYPE_THERMAL))
    {
        Info->DeviceCount++;
        return (AE_OK);
    }

    /* We are only looking for methods named _INI */

    if (!ACPI_COMPARE_NAME (Node->Name.Ascii, METHOD_NAME__INI))
    {
        return (AE_OK);
    }

    /*
     * The only _INI methods that we care about are those that are
     * present under Device, Processor, and Thermal objects.
     */
    ParentNode = AcpiNsGetParentNode (Node);
    switch (ParentNode->Type)
    {
    case ACPI_TYPE_DEVICE:
    case ACPI_TYPE_PROCESSOR:
    case ACPI_TYPE_THERMAL:

        /* Mark parent and bubble up the INI present flag to the root */

        while (ParentNode)
        {
            ParentNode->Flags |= ANOBJ_SUBTREE_HAS_INI;
            ParentNode = AcpiNsGetParentNode (ParentNode);
        }
        break;

    default:
        break;
    }

    return (AE_OK);
}


/*******************************************************************************
 *
 * FUNCTION:    AcpiNsInitOneDevice
 *
 * PARAMETERS:  ACPI_WALK_CALLBACK
 *
 * RETURN:      ACPI_STATUS
 *
 * DESCRIPTION: This is called once per device soon after ACPI is enabled
 *              to initialize each device. It determines if the device is
 *              present, and if so, calls _INI.
 *
 ******************************************************************************/

static ACPI_STATUS
AcpiNsInitOneDevice (
    ACPI_HANDLE             ObjHandle,
    UINT32                  NestingLevel,
    void                    *Context,
    void                    **ReturnValue)
{
    ACPI_DEVICE_WALK_INFO   *WalkInfo = ACPI_CAST_PTR (ACPI_DEVICE_WALK_INFO, Context);
    ACPI_EVALUATE_INFO      *Info = WalkInfo->EvaluateInfo;
    UINT32                  Flags;
    ACPI_STATUS             Status;
    ACPI_NAMESPACE_NODE     *DeviceNode;


    ACPI_FUNCTION_TRACE (NsInitOneDevice);


    /* We are interested in Devices, Processors and ThermalZones only */

    DeviceNode = ACPI_CAST_PTR (ACPI_NAMESPACE_NODE, ObjHandle);
    if ((DeviceNode->Type != ACPI_TYPE_DEVICE)    &&
        (DeviceNode->Type != ACPI_TYPE_PROCESSOR) &&
        (DeviceNode->Type != ACPI_TYPE_THERMAL))
    {
        return_ACPI_STATUS (AE_OK);
    }

    /*
     * Because of an earlier namespace analysis, all subtrees that contain an
     * _INI method are tagged.
     *
     * If this device subtree does not contain any _INI methods, we
     * can exit now and stop traversing this entire subtree.
     */
    if (!(DeviceNode->Flags & ANOBJ_SUBTREE_HAS_INI))
    {
        return_ACPI_STATUS (AE_CTRL_DEPTH);
    }

    /*
     * Run _STA to determine if this device is present and functioning. We
     * must know this information for two important reasons (from ACPI spec):
     *
     * 1) We can only run _INI if the device is present.
     * 2) We must abort the device tree walk on this subtree if the device is
     *    not present and is not functional (we will not examine the children)
     *
     * The _STA method is not required to be present under the device, we
     * assume the device is present if _STA does not exist.
     */
    ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
        ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__STA));

    Status = AcpiUtExecute_STA (DeviceNode, &Flags);
    if (ACPI_FAILURE (Status))
    {
        /* Ignore error and move on to next device */

        return_ACPI_STATUS (AE_OK);
    }

    /*
     * Flags == -1 means that _STA was not found. In this case, we assume that
     * the device is both present and functional.
     *
     * From the ACPI spec, description of _STA:
     *
     * "If a device object (including the processor object) does not have an
     * _STA object, then OSPM assumes that all of the above bits are set (in
     * other words, the device is present, ..., and functioning)"
     */
    if (Flags != ACPI_UINT32_MAX)
    {
        WalkInfo->Num_STA++;
    }

    /*
     * Examine the PRESENT and FUNCTIONING status bits
     *
     * Note: ACPI spec does not seem to specify behavior for the present but
     * not functioning case, so we assume functioning if present.
     */
    if (!(Flags & ACPI_STA_DEVICE_PRESENT))
    {
        /* Device is not present, we must examine the Functioning bit */

        if (Flags & ACPI_STA_DEVICE_FUNCTIONING)
        {
            /*
             * Device is not present but is "functioning". In this case,
             * we will not run _INI, but we continue to examine the children
             * of this device.
             *
             * From the ACPI spec, description of _STA: (Note - no mention
             * of whether to run _INI or not on the device in question)
             *
             * "_STA may return bit 0 clear (not present) with bit 3 set
             * (device is functional). This case is used to indicate a valid
             * device for which no device driver should be loaded (for example,
             * a bridge device.) Children of this device may be present and
             * valid. OSPM should continue enumeration below a device whose
             * _STA returns this bit combination"
             */
            return_ACPI_STATUS (AE_OK);
        }
        else
        {
            /*
             * Device is not present and is not functioning. We must abort the
             * walk of this subtree immediately -- don't look at the children
             * of such a device.
             *
             * From the ACPI spec, description of _INI:
             *
             * "If the _STA method indicates that the device is not present,
             * OSPM will not run the _INI and will not examine the children
             * of the device for _INI methods"
             */
            return_ACPI_STATUS (AE_CTRL_DEPTH);
        }
    }

    /*
     * The device is present or is assumed present if no _STA exists.
     * Run the _INI if it exists (not required to exist)
     *
     * Note: We know there is an _INI within this subtree, but it may not be
     * under this particular device, it may be lower in the branch.
     */
    ACPI_DEBUG_EXEC (AcpiUtDisplayInitPathname (
        ACPI_TYPE_METHOD, DeviceNode, METHOD_NAME__INI));

    Info->PrefixNode = DeviceNode;
    Info->Pathname = METHOD_NAME__INI;
    Info->Parameters = NULL;
    Info->ParameterType = ACPI_PARAM_ARGS;
    Info->Flags = ACPI_IGNORE_RETURN_VALUE;

    Status = AcpiNsEvaluate (Info);
    if (ACPI_SUCCESS (Status))
    {
        WalkInfo->Num_INI++;

        if ((AcpiDbgLevel <= ACPI_LV_ALL_EXCEPTIONS) &&
            (!(AcpiDbgLevel & ACPI_LV_INFO)))
        {
            ACPI_DEBUG_PRINT_RAW ((ACPI_DB_INIT, "."));
        }
    }

#ifdef ACPI_DEBUG_OUTPUT
    else if (Status != AE_NOT_FOUND)
    {
        /* Ignore error and move on to next device */

        char *ScopeName = AcpiNsGetExternalPathname (Info->ResolvedNode);

        ACPI_EXCEPTION ((AE_INFO, Status, "during %s._INI execution",
            ScopeName));
        ACPI_FREE (ScopeName);
    }
#endif

    /* Ignore errors from above */

    Status = AE_OK;

    /*
     * The _INI method has been run if present; call the Global Initialization
     * Handler for this device.
     */
    if (AcpiGbl_InitHandler)
    {
        Status = AcpiGbl_InitHandler (DeviceNode, ACPI_INIT_DEVICE_INI);
    }

    return_ACPI_STATUS (Status);
}