hwsleep.c
// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
* original/legacy sleep/PM registers.
*
* Copyright (C) 2000 - 2019, Intel Corp.
*
*****************************************************************************/
#include <acpi/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);
}
/* Disable all GPEs */
status = acpi_hw_disable_all_gpes();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
status = acpi_hw_clear_acpi_status();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
acpi_gbl_system_awake_and_running = FALSE;
/* Enable all wakeup GPEs */
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_enter_sleep(sleep_state, pm1a_control, pm1b_control);
if (status == AE_CTRL_TERMINATE) {
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 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 */