drivers/acpi/acpica/evgpeinit.c

/******************************************************************************
 *
 * Module Name: evgpeinit - System GPE initialization and update
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2010, 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 "acevents.h"
#include "acnamesp.h"
#include "acinterp.h"

#define _COMPONENT          ACPI_EVENTS
ACPI_MODULE_NAME("evgpeinit")

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_gpe_initialize
 *
 * PARAMETERS:  None
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Initialize the GPE data structures and the FADT GPE 0/1 blocks
 *
 ******************************************************************************/
acpi_status acpi_ev_gpe_initialize(void)
{
	u32 register_count0 = 0;
	u32 register_count1 = 0;
	u32 gpe_number_max = 0;
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_gpe_initialize);

	status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/*
	 * Initialize the GPE Block(s) defined in the FADT
	 *
	 * Why the GPE register block lengths are divided by 2:  From the ACPI
	 * Spec, section "General-Purpose Event Registers", we have:
	 *
	 * "Each register block contains two registers of equal length
	 *  GPEx_STS and GPEx_EN (where x is 0 or 1). The length of the
	 *  GPE0_STS and GPE0_EN registers is equal to half the GPE0_LEN
	 *  The length of the GPE1_STS and GPE1_EN registers is equal to
	 *  half the GPE1_LEN. If a generic register block is not supported
	 *  then its respective block pointer and block length values in the
	 *  FADT table contain zeros. The GPE0_LEN and GPE1_LEN do not need
	 *  to be the same size."
	 */

	/*
	 * Determine the maximum GPE number for this machine.
	 *
	 * Note: both GPE0 and GPE1 are optional, and either can exist without
	 * the other.
	 *
	 * If EITHER the register length OR the block address are zero, then that
	 * particular block is not supported.
	 */
	if (acpi_gbl_FADT.gpe0_block_length &&
	    acpi_gbl_FADT.xgpe0_block.address) {

		/* GPE block 0 exists (has both length and address > 0) */

		register_count0 = (u16)(acpi_gbl_FADT.gpe0_block_length / 2);

		gpe_number_max =
		    (register_count0 * ACPI_GPE_REGISTER_WIDTH) - 1;

		/* Install GPE Block 0 */

		status = acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
						  &acpi_gbl_FADT.xgpe0_block,
						  register_count0, 0,
						  acpi_gbl_FADT.sci_interrupt,
						  &acpi_gbl_gpe_fadt_blocks[0]);

		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"Could not create GPE Block 0"));
		}
	}

	if (acpi_gbl_FADT.gpe1_block_length &&
	    acpi_gbl_FADT.xgpe1_block.address) {

		/* GPE block 1 exists (has both length and address > 0) */

		register_count1 = (u16)(acpi_gbl_FADT.gpe1_block_length / 2);

		/* Check for GPE0/GPE1 overlap (if both banks exist) */

		if ((register_count0) &&
		    (gpe_number_max >= acpi_gbl_FADT.gpe1_base)) {
			ACPI_ERROR((AE_INFO,
				    "GPE0 block (GPE 0 to %u) overlaps the GPE1 block "
				    "(GPE %u to %u) - Ignoring GPE1",
				    gpe_number_max, acpi_gbl_FADT.gpe1_base,
				    acpi_gbl_FADT.gpe1_base +
				    ((register_count1 *
				      ACPI_GPE_REGISTER_WIDTH) - 1)));

			/* Ignore GPE1 block by setting the register count to zero */

			register_count1 = 0;
		} else {
			/* Install GPE Block 1 */

			status =
			    acpi_ev_create_gpe_block(acpi_gbl_fadt_gpe_device,
						     &acpi_gbl_FADT.xgpe1_block,
						     register_count1,
						     acpi_gbl_FADT.gpe1_base,
						     acpi_gbl_FADT.
						     sci_interrupt,
						     &acpi_gbl_gpe_fadt_blocks
						     [1]);

			if (ACPI_FAILURE(status)) {
				ACPI_EXCEPTION((AE_INFO, status,
						"Could not create GPE Block 1"));
			}

			/*
			 * GPE0 and GPE1 do not have to be contiguous in the GPE number
			 * space. However, GPE0 always starts at GPE number zero.
			 */
			gpe_number_max = acpi_gbl_FADT.gpe1_base +
			    ((register_count1 * ACPI_GPE_REGISTER_WIDTH) - 1);
		}
	}

	/* Exit if there are no GPE registers */

	if ((register_count0 + register_count1) == 0) {

		/* GPEs are not required by ACPI, this is OK */

		ACPI_DEBUG_PRINT((ACPI_DB_INIT,
				  "There are no GPE blocks defined in the FADT\n"));
		status = AE_OK;
		goto cleanup;
	}

	/* Check for Max GPE number out-of-range */

	if (gpe_number_max > ACPI_GPE_MAX) {
		ACPI_ERROR((AE_INFO,
			    "Maximum GPE number from FADT is too large: 0x%X",
			    gpe_number_max));
		status = AE_BAD_VALUE;
		goto cleanup;
	}

      cleanup:
	(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_update_gpes
 *
 * PARAMETERS:  table_owner_id      - ID of the newly-loaded ACPI table
 *
 * RETURN:      None
 *
 * DESCRIPTION: Check for new GPE methods (_Lxx/_Exx) made available as a
 *              result of a Load() or load_table() operation. If new GPE
 *              methods have been installed, register the new methods and
 *              enable and runtime GPEs that are associated with them. Also,
 *              run any newly loaded _PRW methods in order to discover any
 *              new CAN_WAKE GPEs.
 *
 ******************************************************************************/

void acpi_ev_update_gpes(acpi_owner_id table_owner_id)
{
	struct acpi_gpe_xrupt_info *gpe_xrupt_info;
	struct acpi_gpe_block_info *gpe_block;
	struct acpi_gpe_walk_info walk_info;
	acpi_status status = AE_OK;
	u32 new_wake_gpe_count = 0;

	/* We will examine only _PRW/_Lxx/_Exx methods owned by this table */

	walk_info.owner_id = table_owner_id;
	walk_info.execute_by_owner_id = TRUE;
	walk_info.count = 0;

	if (acpi_gbl_leave_wake_gpes_disabled) {
		/*
		 * 1) Run any newly-loaded _PRW methods to find any GPEs that
		 * can now be marked as CAN_WAKE GPEs. Note: We must run the
		 * _PRW methods before we process the _Lxx/_Exx methods because
		 * we will enable all runtime GPEs associated with the new
		 * _Lxx/_Exx methods at the time we process those methods.
		 *
		 * Unlock interpreter so that we can run the _PRW methods.
		 */
		walk_info.gpe_block = NULL;
		walk_info.gpe_device = NULL;

		acpi_ex_exit_interpreter();

		status =
		    acpi_ns_walk_namespace(ACPI_TYPE_DEVICE, ACPI_ROOT_OBJECT,
					   ACPI_UINT32_MAX,
					   ACPI_NS_WALK_NO_UNLOCK,
					   acpi_ev_match_prw_and_gpe, NULL,
					   &walk_info, NULL);
		if (ACPI_FAILURE(status)) {
			ACPI_EXCEPTION((AE_INFO, status,
					"While executing _PRW methods"));
		}

		acpi_ex_enter_interpreter();
		new_wake_gpe_count = walk_info.count;
	}

	/*
	 * 2) Find any _Lxx/_Exx GPE methods that have just been loaded.
	 *
	 * Any GPEs that correspond to new _Lxx/_Exx methods and are not
	 * marked as CAN_WAKE are immediately enabled.
	 *
	 * Examine the namespace underneath each gpe_device within the
	 * gpe_block lists.
	 */
	status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
	if (ACPI_FAILURE(status)) {
		return;
	}

	walk_info.count = 0;
	walk_info.enable_this_gpe = TRUE;

	/* Walk the interrupt level descriptor list */

	gpe_xrupt_info = acpi_gbl_gpe_xrupt_list_head;
	while (gpe_xrupt_info) {

		/* Walk all Gpe Blocks attached to this interrupt level */

		gpe_block = gpe_xrupt_info->gpe_block_list_head;
		while (gpe_block) {
			walk_info.gpe_block = gpe_block;
			walk_info.gpe_device = gpe_block->node;

			status = acpi_ns_walk_namespace(ACPI_TYPE_METHOD,
							walk_info.gpe_device,
							ACPI_UINT32_MAX,
							ACPI_NS_WALK_NO_UNLOCK,
							acpi_ev_match_gpe_method,
							NULL, &walk_info, NULL);
			if (ACPI_FAILURE(status)) {
				ACPI_EXCEPTION((AE_INFO, status,
						"While decoding _Lxx/_Exx methods"));
			}

			gpe_block = gpe_block->next;
		}

		gpe_xrupt_info = gpe_xrupt_info->next;
	}

	if (walk_info.count || new_wake_gpe_count) {
		ACPI_INFO((AE_INFO,
			   "Enabled %u new runtime GPEs, added %u new wakeup GPEs",
			   walk_info.count, new_wake_gpe_count));
	}

	(void)acpi_ut_release_mutex(ACPI_MTX_EVENTS);
	return;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_match_gpe_method
 *
 * PARAMETERS:  Callback from walk_namespace
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
 *              control method under the _GPE portion of the namespace.
 *              Extract the name and GPE type from the object, saving this
 *              information for quick lookup during GPE dispatch. Allows a
 *              per-owner_id evaluation if execute_by_owner_id is TRUE in the
 *              walk_info parameter block.
 *
 *              The name of each GPE control method is of the form:
 *              "_Lxx" or "_Exx", where:
 *                  L      - means that the GPE is level triggered
 *                  E      - means that the GPE is edge triggered
 *                  xx     - is the GPE number [in HEX]
 *
 * If walk_info->execute_by_owner_id is TRUE, we only execute examine GPE methods
 *    with that owner.
 * If walk_info->enable_this_gpe is TRUE, the GPE that is referred to by a GPE
 *    method is immediately enabled (Used for Load/load_table operators)
 *
 ******************************************************************************/

acpi_status
acpi_ev_match_gpe_method(acpi_handle obj_handle,
			 u32 level, void *context, void **return_value)
{
	struct acpi_namespace_node *method_node =
	    ACPI_CAST_PTR(struct acpi_namespace_node, obj_handle);
	struct acpi_gpe_walk_info *walk_info =
	    ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
	struct acpi_gpe_event_info *gpe_event_info;
	struct acpi_namespace_node *gpe_device;
	acpi_status status;
	u32 gpe_number;
	char name[ACPI_NAME_SIZE + 1];
	u8 type;

	ACPI_FUNCTION_TRACE(ev_match_gpe_method);

	/* Check if requested owner_id matches this owner_id */

	if ((walk_info->execute_by_owner_id) &&
	    (method_node->owner_id != walk_info->owner_id)) {
		return_ACPI_STATUS(AE_OK);
	}

	/*
	 * Match and decode the _Lxx and _Exx GPE method names
	 *
	 * 1) Extract the method name and null terminate it
	 */
	ACPI_MOVE_32_TO_32(name, &method_node->name.integer);
	name[ACPI_NAME_SIZE] = 0;

	/* 2) Name must begin with an underscore */

	if (name[0] != '_') {
		return_ACPI_STATUS(AE_OK);	/* Ignore this method */
	}

	/*
	 * 3) Edge/Level determination is based on the 2nd character
	 *    of the method name
	 *
	 * NOTE: Default GPE type is RUNTIME only. Later, if a _PRW object is
	 * found that points to this GPE, the ACPI_GPE_CAN_WAKE flag is set.
	 */
	switch (name[1]) {
	case 'L':
		type = ACPI_GPE_LEVEL_TRIGGERED;
		break;

	case 'E':
		type = ACPI_GPE_EDGE_TRIGGERED;
		break;

	default:
		/* Unknown method type, just ignore it */

		ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
				  "Ignoring unknown GPE method type: %s "
				  "(name not of form _Lxx or _Exx)", name));
		return_ACPI_STATUS(AE_OK);
	}

	/* 4) The last two characters of the name are the hex GPE Number */

	gpe_number = ACPI_STRTOUL(&name[2], NULL, 16);
	if (gpe_number == ACPI_UINT32_MAX) {

		/* Conversion failed; invalid method, just ignore it */

		ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
				  "Could not extract GPE number from name: %s "
				  "(name is not of form _Lxx or _Exx)", name));
		return_ACPI_STATUS(AE_OK);
	}

	/* Ensure that we have a valid GPE number for this GPE block */

	gpe_event_info =
	    acpi_ev_low_get_gpe_info(gpe_number, walk_info->gpe_block);
	if (!gpe_event_info) {
		/*
		 * This gpe_number is not valid for this GPE block, just ignore it.
		 * However, it may be valid for a different GPE block, since GPE0
		 * and GPE1 methods both appear under \_GPE.
		 */
		return_ACPI_STATUS(AE_OK);
	}

	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
	    ACPI_GPE_DISPATCH_HANDLER) {

		/* If there is already a handler, ignore this GPE method */

		return_ACPI_STATUS(AE_OK);
	}

	if ((gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) ==
	    ACPI_GPE_DISPATCH_METHOD) {
		/*
		 * If there is already a method, ignore this method. But check
		 * for a type mismatch (if both the _Lxx AND _Exx exist)
		 */
		if (type != (gpe_event_info->flags & ACPI_GPE_XRUPT_TYPE_MASK)) {
			ACPI_ERROR((AE_INFO,
				    "For GPE 0x%.2X, found both _L%2.2X and _E%2.2X methods",
				    gpe_number, gpe_number, gpe_number));
		}
		return_ACPI_STATUS(AE_OK);
	}

	/*
	 * Add the GPE information from above to the gpe_event_info block for
	 * use during dispatch of this GPE.
	 */
	gpe_event_info->flags |= (u8)(type | ACPI_GPE_DISPATCH_METHOD);
	gpe_event_info->dispatch.method_node = method_node;

	/*
	 * Enable this GPE if requested. This only happens when during the
	 * execution of a Load or load_table operator. We have found a new
	 * GPE method and want to immediately enable the GPE if it is a
	 * runtime GPE.
	 */
	if (walk_info->enable_this_gpe) {

		/* Ignore GPEs that can wake the system */

		if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE) ||
		    !acpi_gbl_leave_wake_gpes_disabled) {
			walk_info->count++;
			gpe_device = walk_info->gpe_device;

			if (gpe_device == acpi_gbl_fadt_gpe_device) {
				gpe_device = NULL;
			}

			status = acpi_enable_gpe(gpe_device, gpe_number,
						 ACPI_GPE_TYPE_RUNTIME);
			if (ACPI_FAILURE(status)) {
				ACPI_EXCEPTION((AE_INFO, status,
						"Could not enable GPE 0x%02X",
						gpe_number));
			}
		}
	}

	ACPI_DEBUG_PRINT((ACPI_DB_LOAD,
			  "Registered GPE method %s as GPE number 0x%.2X\n",
			  name, gpe_number));
	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_ev_match_prw_and_gpe
 *
 * PARAMETERS:  Callback from walk_namespace
 *
 * RETURN:      Status. NOTE: We ignore errors so that the _PRW walk is
 *              not aborted on a single _PRW failure.
 *
 * DESCRIPTION: Called from acpi_walk_namespace. Expects each object to be a
 *              Device. Run the _PRW method. If present, extract the GPE
 *              number and mark the GPE as a CAN_WAKE GPE. Allows a
 *              per-owner_id execution if execute_by_owner_id is TRUE in the
 *              walk_info parameter block.
 *
 * If walk_info->execute_by_owner_id is TRUE, we only execute _PRWs with that
 *    owner.
 * If walk_info->gpe_device is NULL, we execute every _PRW found. Otherwise,
 *    we only execute _PRWs that refer to the input gpe_device.
 *
 ******************************************************************************/

acpi_status
acpi_ev_match_prw_and_gpe(acpi_handle obj_handle,
			  u32 level, void *context, void **return_value)
{
	struct acpi_gpe_walk_info *walk_info =
	    ACPI_CAST_PTR(struct acpi_gpe_walk_info, context);
	struct acpi_namespace_node *gpe_device;
	struct acpi_gpe_block_info *gpe_block;
	struct acpi_namespace_node *target_gpe_device;
	struct acpi_namespace_node *prw_node;
	struct acpi_gpe_event_info *gpe_event_info;
	union acpi_operand_object *pkg_desc;
	union acpi_operand_object *obj_desc;
	u32 gpe_number;
	acpi_status status;

	ACPI_FUNCTION_TRACE(ev_match_prw_and_gpe);

	/* Check for a _PRW method under this device */

	status = acpi_ns_get_node(obj_handle, METHOD_NAME__PRW,
				  ACPI_NS_NO_UPSEARCH, &prw_node);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(AE_OK);
	}

	/* Check if requested owner_id matches this owner_id */

	if ((walk_info->execute_by_owner_id) &&
	    (prw_node->owner_id != walk_info->owner_id)) {
		return_ACPI_STATUS(AE_OK);
	}

	/* Execute the _PRW */

	status = acpi_ut_evaluate_object(prw_node, NULL,
					 ACPI_BTYPE_PACKAGE, &pkg_desc);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(AE_OK);
	}

	/* The returned _PRW package must have at least two elements */

	if (pkg_desc->package.count < 2) {
		goto cleanup;
	}

	/* Extract pointers from the input context */

	gpe_device = walk_info->gpe_device;
	gpe_block = walk_info->gpe_block;

	/*
	 * The _PRW object must return a package, we are only interested
	 * in the first element
	 */
	obj_desc = pkg_desc->package.elements[0];

	if (obj_desc->common.type == ACPI_TYPE_INTEGER) {

		/* Use FADT-defined GPE device (from definition of _PRW) */

		target_gpe_device = NULL;
		if (gpe_device) {
			target_gpe_device = acpi_gbl_fadt_gpe_device;
		}

		/* Integer is the GPE number in the FADT described GPE blocks */

		gpe_number = (u32)obj_desc->integer.value;
	} else if (obj_desc->common.type == ACPI_TYPE_PACKAGE) {

		/* Package contains a GPE reference and GPE number within a GPE block */

		if ((obj_desc->package.count < 2) ||
		    ((obj_desc->package.elements[0])->common.type !=
		     ACPI_TYPE_LOCAL_REFERENCE) ||
		    ((obj_desc->package.elements[1])->common.type !=
		     ACPI_TYPE_INTEGER)) {
			goto cleanup;
		}

		/* Get GPE block reference and decode */

		target_gpe_device =
		    obj_desc->package.elements[0]->reference.node;
		gpe_number = (u32)obj_desc->package.elements[1]->integer.value;
	} else {
		/* Unknown type, just ignore it */

		goto cleanup;
	}

	/* Get the gpe_event_info for this GPE */

	if (gpe_device) {
		/*
		 * Is this GPE within this block?
		 *
		 * TRUE if and only if these conditions are true:
		 *     1) The GPE devices match.
		 *     2) The GPE index(number) is within the range of the Gpe Block
		 *          associated with the GPE device.
		 */
		if (gpe_device != target_gpe_device) {
			goto cleanup;
		}

		gpe_event_info =
		    acpi_ev_low_get_gpe_info(gpe_number, gpe_block);
	} else {
		/* gpe_device is NULL, just match the target_device and gpe_number */

		gpe_event_info =
		    acpi_ev_get_gpe_event_info(target_gpe_device, gpe_number);
	}

	if (gpe_event_info) {
		if (!(gpe_event_info->flags & ACPI_GPE_CAN_WAKE)) {

			/* This GPE can wake the system */

			gpe_event_info->flags |= ACPI_GPE_CAN_WAKE;
			walk_info->count++;
		}
	}

      cleanup:
	acpi_ut_remove_reference(pkg_desc);
	return_ACPI_STATUS(AE_OK);
}