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alistair23-linux/drivers/acpi/acpica/hwsleep.c
Len Brown 3f6f49c785 ACPI: delete _GTS/_BFS support 
_GTS and _BFS were added to the suspend/resume flow
in the ACPI 2.0 specification.

Linux dutifully implemented _GTS and _BFS.
We discovered that it was rarely seen in systems
in the field.  Further, some of those systems had
AML so bogus that it could never work -- proof that
no other operating system supports _GTS and _BFS.
So we made _GTS and _BFS optional via modparam,
and disabled them by default.

But we've had to complicate some code to keep
this support in the kernel, as these methods are defined
to be evaluated very close to sleep entry and exit.
Indeed, no other AML is ever evaluated with interrupts off.

We have submitted a proposal for _GTS and _BFS
to be officially removed from the ACPI specification
on the next revision.  Here we remove it from Linux.

Signed-off-by: Len Brown <len.brown@intel.com>
Acked-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
2012-07-30 21:11:25 -04:00

346 lines
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/******************************************************************************
*
* Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
* original/legacy sleep/PM 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 <linux/acpi.h>
#include "accommon.h"
#include <linux/module.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(10000000);
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.
*/
acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
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 */
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