linux/linux-5.4.31/drivers/acpi/acpica/exsystem.c

275 lines
7.3 KiB
C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: exsystem - Interface to OS services
*
* Copyright (C) 2000 - 2019, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acinterp.h"
#define _COMPONENT ACPI_EXECUTER
ACPI_MODULE_NAME("exsystem")
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_wait_semaphore
*
* PARAMETERS: semaphore - Semaphore to wait on
* timeout - Max time to wait
*
* RETURN: Status
*
* DESCRIPTION: Implements a semaphore wait with a check to see if the
* semaphore is available immediately. If it is not, the
* interpreter is released before waiting.
*
******************************************************************************/
acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
{
acpi_status status;
ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
if (ACPI_SUCCESS(status)) {
return_ACPI_STATUS(status);
}
if (status == AE_TIME) {
/* We must wait, so unlock the interpreter */
acpi_ex_exit_interpreter();
status = acpi_os_wait_semaphore(semaphore, 1, timeout);
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"*** Thread awake after blocking, %s\n",
acpi_format_exception(status)));
/* Reacquire the interpreter */
acpi_ex_enter_interpreter();
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_wait_mutex
*
* PARAMETERS: mutex - Mutex to wait on
* timeout - Max time to wait
*
* RETURN: Status
*
* DESCRIPTION: Implements a mutex wait with a check to see if the
* mutex is available immediately. If it is not, the
* interpreter is released before waiting.
*
******************************************************************************/
acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
{
acpi_status status;
ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
if (ACPI_SUCCESS(status)) {
return_ACPI_STATUS(status);
}
if (status == AE_TIME) {
/* We must wait, so unlock the interpreter */
acpi_ex_exit_interpreter();
status = acpi_os_acquire_mutex(mutex, timeout);
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"*** Thread awake after blocking, %s\n",
acpi_format_exception(status)));
/* Reacquire the interpreter */
acpi_ex_enter_interpreter();
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_do_stall
*
* PARAMETERS: how_long - The amount of time to stall,
* in microseconds
*
* RETURN: Status
*
* DESCRIPTION: Suspend running thread for specified amount of time.
* Note: ACPI specification requires that Stall() does not
* relinquish the processor, and delays longer than 100 usec
* should use Sleep() instead. We allow stalls up to 255 usec
* for compatibility with other interpreters and existing BIOSs.
*
******************************************************************************/
acpi_status acpi_ex_system_do_stall(u32 how_long)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_ENTRY();
if (how_long > 255) { /* 255 microseconds */
/*
* Longer than 255 usec, this is an error
*
* (ACPI specifies 100 usec as max, but this gives some slack in
* order to support existing BIOSs)
*/
ACPI_ERROR((AE_INFO,
"Time parameter is too large (%u)", how_long));
status = AE_AML_OPERAND_VALUE;
} else {
acpi_os_stall(how_long);
}
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_do_sleep
*
* PARAMETERS: how_long - The amount of time to sleep,
* in milliseconds
*
* RETURN: None
*
* DESCRIPTION: Sleep the running thread for specified amount of time.
*
******************************************************************************/
acpi_status acpi_ex_system_do_sleep(u64 how_long)
{
ACPI_FUNCTION_ENTRY();
/* Since this thread will sleep, we must release the interpreter */
acpi_ex_exit_interpreter();
/*
* For compatibility with other ACPI implementations and to prevent
* accidental deep sleeps, limit the sleep time to something reasonable.
*/
if (how_long > ACPI_MAX_SLEEP) {
how_long = ACPI_MAX_SLEEP;
}
acpi_os_sleep(how_long);
/* And now we must get the interpreter again */
acpi_ex_enter_interpreter();
return (AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_signal_event
*
* PARAMETERS: obj_desc - The object descriptor for this op
*
* RETURN: Status
*
* DESCRIPTION: Provides an access point to perform synchronization operations
* within the AML.
*
******************************************************************************/
acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(ex_system_signal_event);
if (obj_desc) {
status =
acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_wait_event
*
* PARAMETERS: time_desc - The 'time to delay' object descriptor
* obj_desc - The object descriptor for this op
*
* RETURN: Status
*
* DESCRIPTION: Provides an access point to perform synchronization operations
* within the AML. This operation is a request to wait for an
* event.
*
******************************************************************************/
acpi_status
acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
union acpi_operand_object *obj_desc)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(ex_system_wait_event);
if (obj_desc) {
status =
acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
(u16) time_desc->integer.
value);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ex_system_reset_event
*
* PARAMETERS: obj_desc - The object descriptor for this op
*
* RETURN: Status
*
* DESCRIPTION: Reset an event to a known state.
*
******************************************************************************/
acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
{
acpi_status status = AE_OK;
acpi_semaphore temp_semaphore;
ACPI_FUNCTION_ENTRY();
/*
* We are going to simply delete the existing semaphore and
* create a new one!
*/
status =
acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
if (ACPI_SUCCESS(status)) {
(void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
obj_desc->event.os_semaphore = temp_semaphore;
}
return (status);
}