linux/drivers/acpi/acpica/hwesleep.c
Lin Ming 8a73b17e4c ACPICA: Sleep/Wake interfaces: optionally execute _GTS and _BFS
Enhanced the sleep/wake interfaces to optionally execute the
_GTS method (Going To Sleep), and the _BFS method (Back From
Sleep).  Windows apparently does not execute these methods, and
therefore these methods are often untested. It has been seen on
some systems where the execution of these methods causes errors
and also prevents the machine from entering S5. It is therefore
suggested that host operating systems do not execute these methods
by default. In the future, perhaps these methods can be optionally
executed based on the age of the system and/or what is the newest
version of Windows that the BIOS asks for via _OSI.

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
2012-03-26 21:16:25 -04:00

261 lines
8.3 KiB
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_pathname - 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_pathname, 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_PATHNAME__GTS, method_pathname) && !gts)
return_VOID;
if (!ACPI_STRCMP(METHOD_PATHNAME__BFS, method_pathname) && !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_pathname, &arg_list, NULL);
if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
ACPI_EXCEPTION((AE_INFO, status, "While executing method %s",
method_pathname));
}
return_VOID;
}
/*******************************************************************************
*
* FUNCTION: acpi_hw_extended_sleep
*
* PARAMETERS: sleep_state - Which sleep state to enter
* Flags - ACPI_EXECUTE_GTS to run optional method
*
* 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, u8 flags)
{
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;
/* Optionally execute _GTS (Going To Sleep) */
if (flags & ACPI_EXECUTE_GTS) {
acpi_hw_execute_sleep_method(METHOD_PATHNAME__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
* Flags - ACPI_EXECUTE_BFS to run optional method
*
* 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, u8 flags)
{
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);
}
/* Optionally execute _BFS (Back From Sleep) */
if (flags & ACPI_EXECUTE_BFS) {
acpi_hw_execute_sleep_method(METHOD_PATHNAME__BFS, sleep_state);
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_hw_extended_wake
*
* PARAMETERS: sleep_state - Which sleep state we just exited
* Flags - Reserved, set to zero
*
* RETURN: Status
*
* DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
* Called with interrupts ENABLED.
*
******************************************************************************/
acpi_status acpi_hw_extended_wake(u8 sleep_state, u8 flags)
{
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_PATHNAME__SST, ACPI_SST_WAKING);
acpi_hw_execute_sleep_method(METHOD_PATHNAME__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_PATHNAME__SST, ACPI_SST_WORKING);
return_ACPI_STATUS(AE_OK);
}