hwesleep.c

/******************************************************************************
 *
 * Name: hwesleep.c - ACPI Hardware Sleep/Wake Support functions for the
 *                    extended FADT-V5 sleep registers.
 *
 *****************************************************************************/

/*
 * 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 <linux/module.h>

#define _COMPONENT          ACPI_HARDWARE
ACPI_MODULE_NAME("hwesleep")

static unsigned int gts, bfs;
module_param(gts, uint, 0644);
module_param(bfs, uint, 0644);
MODULE_PARM_DESC(gts, "Enable evaluation of _GTS on suspend.");
MODULE_PARM_DESC(bfs, "Enable evaluation of _BFS on resume".);

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_execute_sleep_method
 *
 * PARAMETERS:  method_name         - Pathname of method to execute
 *              integer_argument    - Argument to pass to the method
 *
 * RETURN:      None
 *
 * DESCRIPTION: Execute a sleep/wake related method with one integer argument
 *              and no return value.
 *
 ******************************************************************************/
void acpi_hw_execute_sleep_method(char *method_name, u32 integer_argument)
{
	struct acpi_object_list arg_list;
	union acpi_object arg;
	acpi_status status;

	ACPI_FUNCTION_TRACE(hw_execute_sleep_method);

	if (!ACPI_STRCMP(METHOD_NAME__GTS, method_name) && !gts)
		return_VOID;

	if (!ACPI_STRCMP(METHOD_NAME__BFS, method_name) && !bfs)
		return_VOID;

	/* One argument, integer_argument; No return value expected */

	arg_list.count = 1;
	arg_list.pointer = &arg;
	arg.type = ACPI_TYPE_INTEGER;
	arg.integer.value = (u64)integer_argument;

	status = acpi_evaluate_object(NULL, method_name, &arg_list, NULL);
	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_EXCEPTION((AE_INFO, status, "While executing method %s",
				method_name));
	}

	return_VOID;
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_extended_sleep
 *
 * PARAMETERS:  sleep_state         - Which sleep state to enter
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Enter a system sleep state via the extended FADT sleep
 *              registers (V5 FADT).
 *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
 *
 ******************************************************************************/

acpi_status acpi_hw_extended_sleep(u8 sleep_state)
{
	acpi_status status;
	u8 sleep_type_value;
	u64 sleep_status;

	ACPI_FUNCTION_TRACE(hw_extended_sleep);

	/* Extended sleep registers must be valid */

	if (!acpi_gbl_FADT.sleep_control.address ||
	    !acpi_gbl_FADT.sleep_status.address) {
		return_ACPI_STATUS(AE_NOT_EXIST);
	}

	/* Clear wake status (WAK_STS) */

	status = acpi_write(ACPI_X_WAKE_STATUS, &acpi_gbl_FADT.sleep_status);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	acpi_gbl_system_awake_and_running = FALSE;

	/* Execute the _GTS method (Going To Sleep) */

	acpi_hw_execute_sleep_method(METHOD_NAME__GTS, sleep_state);

	/* Flush caches, as per ACPI specification */

	ACPI_FLUSH_CPU_CACHE();

	/*
	 * Set the SLP_TYP and SLP_EN bits.
	 *
	 * Note: We only use the first value returned by the \_Sx method
	 * (acpi_gbl_sleep_type_a) - As per ACPI specification.
	 */
	ACPI_DEBUG_PRINT((ACPI_DB_INIT,
			  "Entering sleep state [S%u]\n", sleep_state));

	sleep_type_value =
	    ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
	     ACPI_X_SLEEP_TYPE_MASK);

	status = acpi_write((sleep_type_value | ACPI_X_SLEEP_ENABLE),
			    &acpi_gbl_FADT.sleep_control);
	if (ACPI_FAILURE(status)) {
		return_ACPI_STATUS(status);
	}

	/* Wait for transition back to Working State */

	do {
		status = acpi_read(&sleep_status, &acpi_gbl_FADT.sleep_status);
		if (ACPI_FAILURE(status)) {
			return_ACPI_STATUS(status);
		}

	} while (!(((u8)sleep_status) & ACPI_X_WAKE_STATUS));

	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_extended_wake_prep
 *
 * PARAMETERS:  sleep_state         - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform first part of OS-independent ACPI cleanup after
 *              a sleep. Called with interrupts ENABLED.
 *
 ******************************************************************************/

acpi_status acpi_hw_extended_wake_prep(u8 sleep_state)
{
	acpi_status status;
	u8 sleep_type_value;

	ACPI_FUNCTION_TRACE(hw_extended_wake_prep);

	status = acpi_get_sleep_type_data(ACPI_STATE_S0,
					  &acpi_gbl_sleep_type_a,
					  &acpi_gbl_sleep_type_b);
	if (ACPI_SUCCESS(status)) {
		sleep_type_value =
		    ((acpi_gbl_sleep_type_a << ACPI_X_SLEEP_TYPE_POSITION) &
		     ACPI_X_SLEEP_TYPE_MASK);

		(void)acpi_write((sleep_type_value | ACPI_X_SLEEP_ENABLE),
				 &acpi_gbl_FADT.sleep_control);
	}

	acpi_hw_execute_sleep_method(METHOD_NAME__BFS, sleep_state);
	return_ACPI_STATUS(AE_OK);
}

/*******************************************************************************
 *
 * FUNCTION:    acpi_hw_extended_wake
 *
 * PARAMETERS:  sleep_state         - Which sleep state we just exited
 *
 * RETURN:      Status
 *
 * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 *              Called with interrupts ENABLED.
 *
 ******************************************************************************/

acpi_status acpi_hw_extended_wake(u8 sleep_state)
{
	ACPI_FUNCTION_TRACE(hw_extended_wake);

	/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */

	acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;

	/* Execute the wake methods */

	acpi_hw_execute_sleep_method(METHOD_NAME__SST, ACPI_SST_WAKING);
	acpi_hw_execute_sleep_method(METHOD_NAME__WAK, sleep_state);

	/*
	 * Some BIOS code assumes that WAK_STS will be cleared on resume
	 * and use it to determine whether the system is rebooting or
	 * resuming. Clear WAK_STS for compatibility.
	 */
	(void)acpi_write(ACPI_X_WAKE_STATUS, &acpi_gbl_FADT.sleep_status);
	acpi_gbl_system_awake_and_running = TRUE;

	acpi_hw_execute_sleep_method(METHOD_NAME__SST, ACPI_SST_WORKING);
	return_ACPI_STATUS(AE_OK);
}