https://github.com/torvalds/linux
Tip revision: 69973b830859bc6529a7a0468ba0d80ee5117826 authored by Linus Torvalds on 11 December 2016, 19:17:54 UTC
Linux 4.9
Linux 4.9
Tip revision: 69973b8
hwsleep.c
/******************************************************************************
*
* Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
* original/legacy sleep/PM registers.
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2016, 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 <linux/acpi.h>
#include "accommon.h"
#define _COMPONENT ACPI_HARDWARE
ACPI_MODULE_NAME("hwsleep")
#if (!ACPI_REDUCED_HARDWARE) /* Entire module */
/*******************************************************************************
*
* FUNCTION: acpi_hw_legacy_sleep
*
* PARAMETERS: sleep_state - Which sleep state to enter
*
* RETURN: Status
*
* DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
* THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
*
******************************************************************************/
acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
{
struct acpi_bit_register_info *sleep_type_reg_info;
struct acpi_bit_register_info *sleep_enable_reg_info;
u32 pm1a_control;
u32 pm1b_control;
u32 in_value;
acpi_status status;
ACPI_FUNCTION_TRACE(hw_legacy_sleep);
sleep_type_reg_info =
acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
sleep_enable_reg_info =
acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
/* Clear wake status */
status = acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
ACPI_CLEAR_STATUS);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Clear all fixed and general purpose status bits */
status = acpi_hw_clear_acpi_status();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* 1) Disable/Clear all GPEs
* 2) Enable all wakeup GPEs
*/
status = acpi_hw_disable_all_gpes();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
acpi_gbl_system_awake_and_running = FALSE;
status = acpi_hw_enable_all_wakeup_gpes();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Get current value of PM1A control */
status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
&pm1a_control);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
ACPI_DEBUG_PRINT((ACPI_DB_INIT,
"Entering sleep state [S%u]\n", sleep_state));
/* Clear the SLP_EN and SLP_TYP fields */
pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
sleep_enable_reg_info->access_bit_mask);
pm1b_control = pm1a_control;
/* Insert the SLP_TYP bits */
pm1a_control |=
(acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
pm1b_control |=
(acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
/*
* We split the writes of SLP_TYP and SLP_EN to workaround
* poorly implemented hardware.
*/
/* Write #1: write the SLP_TYP data to the PM1 Control registers */
status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/* Insert the sleep enable (SLP_EN) bit */
pm1a_control |= sleep_enable_reg_info->access_bit_mask;
pm1b_control |= sleep_enable_reg_info->access_bit_mask;
/* Flush caches, as per ACPI specification */
ACPI_FLUSH_CPU_CACHE();
status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
pm1b_control);
if (ACPI_SKIP(status))
return_ACPI_STATUS(AE_OK);
if (ACPI_FAILURE(status))
return_ACPI_STATUS(status);
/* Write #2: Write both SLP_TYP + SLP_EN */
status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
if (sleep_state > ACPI_STATE_S3) {
/*
* We wanted to sleep > S3, but it didn't happen (by virtue of the
* fact that we are still executing!)
*
* Wait ten seconds, then try again. This is to get S4/S5 to work on
* all machines.
*
* We wait so long to allow chipsets that poll this reg very slowly
* to still read the right value. Ideally, this block would go
* away entirely.
*/
acpi_os_stall(10 * ACPI_USEC_PER_SEC);
status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
sleep_enable_reg_info->
access_bit_mask);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
/* Wait for transition back to Working State */
do {
status =
acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
} while (!in_value);
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_hw_legacy_wake_prep
*
* PARAMETERS: sleep_state - Which sleep state we just exited
*
* RETURN: Status
*
* DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
* sleep.
* Called with interrupts ENABLED.
*
******************************************************************************/
acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
{
acpi_status status;
struct acpi_bit_register_info *sleep_type_reg_info;
struct acpi_bit_register_info *sleep_enable_reg_info;
u32 pm1a_control;
u32 pm1b_control;
ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
/*
* Set SLP_TYPE and SLP_EN to state S0.
* This is unclear from the ACPI Spec, but it is required
* by some machines.
*/
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_reg_info =
acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
sleep_enable_reg_info =
acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
/* Get current value of PM1A control */
status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
&pm1a_control);
if (ACPI_SUCCESS(status)) {
/* Clear the SLP_EN and SLP_TYP fields */
pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
sleep_enable_reg_info->
access_bit_mask);
pm1b_control = pm1a_control;
/* Insert the SLP_TYP bits */
pm1a_control |= (acpi_gbl_sleep_type_a <<
sleep_type_reg_info->bit_position);
pm1b_control |= (acpi_gbl_sleep_type_b <<
sleep_type_reg_info->bit_position);
/* Write the control registers and ignore any errors */
(void)acpi_hw_write_pm1_control(pm1a_control,
pm1b_control);
}
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_hw_legacy_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_legacy_wake(u8 sleep_state)
{
acpi_status status;
ACPI_FUNCTION_TRACE(hw_legacy_wake);
/* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
/*
* GPEs must be enabled before _WAK is called as GPEs
* might get fired there
*
* Restore the GPEs:
* 1) Disable/Clear all GPEs
* 2) Enable all runtime GPEs
*/
status = acpi_hw_disable_all_gpes();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
status = acpi_hw_enable_all_runtime_gpes();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* Now we can execute _WAK, etc. Some machines require that the GPEs
* are enabled before the wake methods are executed.
*/
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_bit_register(ACPI_BITREG_WAKE_STATUS,
ACPI_CLEAR_STATUS);
acpi_gbl_system_awake_and_running = TRUE;
/* Enable power button */
(void)
acpi_write_bit_register(acpi_gbl_fixed_event_info
[ACPI_EVENT_POWER_BUTTON].
enable_register_id, ACPI_ENABLE_EVENT);
(void)
acpi_write_bit_register(acpi_gbl_fixed_event_info
[ACPI_EVENT_POWER_BUTTON].
status_register_id, ACPI_CLEAR_STATUS);
acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
return_ACPI_STATUS(status);
}
#endif /* !ACPI_REDUCED_HARDWARE */