/**
******************************************************************************
* @file stm32_seq.c
* @author MCD Application Team
* @brief Simple sequencer implementation
******************************************************************************
* @attention
*
* <h2><center>© Copyright (c) 2019 STMicroelectronics.
* All rights reserved.</center></h2>
*
* This software is licensed under terms that can be found in the LICENSE file
* in the root directory of this software component.
* If no LICENSE file comes with this software, it is provided AS-IS.
*
******************************************************************************
*/
/* Includes ------------------------------------------------------------------*/
#include "stm32_seq.h"
#include "utilities_conf.h"
/** @addtogroup SEQUENCER
* @{
*/
/* Private typedef -----------------------------------------------------------*/
/** @defgroup SEQUENCER_Private_type SEQUENCER private type
* @{
*/
/**
* @brief structure used to manage task scheduling
*/
typedef struct
{
uint32_t priority; /*!<bit field of the enabled task. */
uint32_t round_robin; /*!<mask on the allowed task to be running. */
} UTIL_SEQ_Priority_t;
/**
* @}
*/
/* Private defines -----------------------------------------------------------*/
/** @defgroup SEQUENCER_Private_define SEQUENCER private defines
* @{
*/
/**
* @brief macro used to enter the critical section before calling the IDLE function
* @note in a basic configuration shall be identical to the macro
* UTIL_SEQ_ENTER_CRITICAL_SECTION. The redefinition of this macro will allow
* to perform specific operation
*/
#ifndef UTIL_SEQ_ENTER_CRITICAL_SECTION_IDLE
#define UTIL_SEQ_ENTER_CRITICAL_SECTION_IDLE( ) UTIL_SEQ_ENTER_CRITICAL_SECTION( )
#endif
/**
* @brief macro used to exit the critical section when exiting the IDLE function
* @note the behavior of the macro shall be symmetrical with the macro
* UTIL_SEQ_ENTER_CRITICAL_SECTION_IDLE
*/
#ifndef UTIL_SEQ_EXIT_CRITICAL_SECTION_IDLE
#define UTIL_SEQ_EXIT_CRITICAL_SECTION_IDLE( ) UTIL_SEQ_EXIT_CRITICAL_SECTION( )
#endif
/**
* @brief define to represent no task running
*/
#define UTIL_SEQ_NOTASKRUNNING (0xFFFFFFFFU)
/**
* @brief define to represent no bit set inside uint32_t mapping
*/
#define UTIL_SEQ_NO_BIT_SET (0U)
/**
* @brief define to represent all bits set inside uint32_t mapping
*/
#define UTIL_SEQ_ALL_BIT_SET (~0U)
/**
* @brief default number of task is default 32 (maximum), can be reduced by redefining in utilities_conf.h
*/
#ifndef UTIL_SEQ_CONF_TASK_NBR
#define UTIL_SEQ_CONF_TASK_NBR (32)
#endif
#if UTIL_SEQ_CONF_TASK_NBR > 32
#error "UTIL_SEQ_CONF_PRIO_NBR must be less of equal then 32"
#endif
/**
* @brief default value of priority number.
*/
#ifndef UTIL_SEQ_CONF_PRIO_NBR
#define UTIL_SEQ_CONF_PRIO_NBR (2)
#endif
/**
* @brief default memset function.
*/
#ifndef UTIL_SEQ_MEMSET8
#define UTIL_SEQ_MEMSET8( dest, value, size ) UTILS_MEMSET8( dest, value, size )
#endif
/**
* @}
*/
/* Private variables ---------------------------------------------------------*/
/** @defgroup SEQUENCER_Private_varaible SEQUENCER private variables
* @{
*/
/**
* @brief task set.
*/
static volatile UTIL_SEQ_bm_t TaskSet;
/**
* @brief task mask.
*/
static volatile UTIL_SEQ_bm_t TaskMask = UTIL_SEQ_ALL_BIT_SET;
/**
* @brief super mask.
*/
static UTIL_SEQ_bm_t SuperMask = UTIL_SEQ_ALL_BIT_SET;
/**
* @brief evt set mask.
*/
static volatile UTIL_SEQ_bm_t EvtSet = UTIL_SEQ_NO_BIT_SET;
/**
* @brief evt expected mask.
*/
static volatile UTIL_SEQ_bm_t EvtWaited = UTIL_SEQ_NO_BIT_SET;
/**
* @brief current task id.
*/
static uint32_t CurrentTaskIdx = 0U;
/**
* @brief task function registered.
*/
static void (*TaskCb[UTIL_SEQ_CONF_TASK_NBR])( void );
/**
* @brief task prio management.
*/
static volatile UTIL_SEQ_Priority_t TaskPrio[UTIL_SEQ_CONF_PRIO_NBR];
/**
* @}
*/
/* Private function prototypes -----------------------------------------------*/
/** @defgroup SEQUENCER_Private_function SEQUENCER private functions
* @{
*/
uint8_t SEQ_BitPosition(uint32_t Value);
/**
* @}
*/
/* Functions Definition ------------------------------------------------------*/
/** @addtogroup SEQUENCER_Exported_function SEQUENCER exported functions
* @{
*/
void UTIL_SEQ_Init( void )
{
TaskSet = UTIL_SEQ_NO_BIT_SET;
TaskMask = UTIL_SEQ_ALL_BIT_SET;
SuperMask = UTIL_SEQ_ALL_BIT_SET;
EvtSet = UTIL_SEQ_NO_BIT_SET;
EvtWaited = UTIL_SEQ_NO_BIT_SET;
CurrentTaskIdx = 0U;
(void)UTIL_SEQ_MEMSET8((uint8_t *)TaskCb, 0, sizeof(TaskCb));
for(uint32_t index = 0; index < UTIL_SEQ_CONF_PRIO_NBR; index++)
{
TaskPrio[index].priority = 0;
TaskPrio[index].round_robin = 0;
}
UTIL_SEQ_INIT_CRITICAL_SECTION( );
}
void UTIL_SEQ_DeInit( void )
{
}
/**
* This function can be nested.
* That is the reason why many variables that are used only in that function are declared static.
* Note: These variables could have been declared static in the function.
*
*/
void UTIL_SEQ_Run( UTIL_SEQ_bm_t Mask_bm )
{
uint32_t counter;
UTIL_SEQ_bm_t current_task_set;
UTIL_SEQ_bm_t super_mask_backup;
UTIL_SEQ_bm_t local_taskset;
UTIL_SEQ_bm_t local_evtset;
UTIL_SEQ_bm_t local_taskmask;
UTIL_SEQ_bm_t local_evtwaited;
/*
* When this function is nested, the mask to be applied cannot be larger than the first call
* The mask is always getting smaller and smaller
* A copy is made of the mask set by UTIL_SEQ_Run() in case it is called again in the task
*/
super_mask_backup = SuperMask;
SuperMask &= Mask_bm;
/*
* There are two independent mask to check:
* TaskMask that comes from UTIL_SEQ_PauseTask() / UTIL_SEQ_ResumeTask
* SuperMask that comes from UTIL_SEQ_Run
* If the waited event is there, exit from UTIL_SEQ_Run() to return to the
* waiting task
*/
local_taskset = TaskSet;
local_evtset = EvtSet;
local_taskmask = TaskMask;
local_evtwaited = EvtWaited;
while(((local_taskset & local_taskmask & SuperMask) != 0U) && ((local_evtset & local_evtwaited)==0U))
{
counter = 0U;
/*
* When a flag is set, the associated bit is set in TaskPrio[counter].priority mask depending
* on the priority parameter given from UTIL_SEQ_SetTask()
* The while loop is looking for a flag set from the highest priority maskr to the lower
*/
while((TaskPrio[counter].priority & local_taskmask & SuperMask)== 0U)
{
counter++;
}
current_task_set = TaskPrio[counter].priority & local_taskmask & SuperMask;
/*
* The round_robin register is a mask of allowed flags to be evaluated.
* The concept is to make sure that on each round on UTIL_SEQ_Run(), if two same flags are always set,
* the sequencer does not run always only the first one.
* When a task has been executed, The flag is removed from the round_robin mask.
* If on the next UTIL_SEQ_RUN(), the two same flags are set again, the round_robin mask will mask out the first flag
* so that the second one can be executed.
* Note that the first flag is not removed from the list of pending task but just masked by the round_robin mask
*
* In the check below, the round_robin mask is reinitialize in case all pending tasks haven been executed at least once
*/
if ((TaskPrio[counter].round_robin & current_task_set) == 0U)
{
TaskPrio[counter].round_robin = UTIL_SEQ_ALL_BIT_SET;
}
/*
* Read the flag index of the task to be executed
* Once the index is read, the associated task will be executed even though a higher priority stack is requested
* before task execution.
*/
CurrentTaskIdx = (SEQ_BitPosition(current_task_set & TaskPrio[counter].round_robin));
/*
* remove from the roun_robin mask the task that has been selected to be executed
*/
TaskPrio[counter].round_robin &= ~(1U << CurrentTaskIdx);
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
/* remove from the list or pending task the one that has been selected to be executed */
TaskSet &= ~(1U << CurrentTaskIdx);
/* remove from all priority mask the task that has been selected to be executed */
for (counter = UTIL_SEQ_CONF_PRIO_NBR; counter != 0U; counter--)
{
TaskPrio[counter - 1U].priority &= ~(1U << CurrentTaskIdx);
}
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
/* Execute the task */
TaskCb[CurrentTaskIdx]( );
local_taskset = TaskSet;
local_evtset = EvtSet;
local_taskmask = TaskMask;
local_evtwaited = EvtWaited;
}
/* the set of CurrentTaskIdx to no task running allows to call WaitEvt in the Pre/Post ilde context */
CurrentTaskIdx = UTIL_SEQ_NOTASKRUNNING;
UTIL_SEQ_PreIdle( );
UTIL_SEQ_ENTER_CRITICAL_SECTION_IDLE( );
local_taskset = TaskSet;
local_evtset = EvtSet;
local_taskmask = TaskMask;
if ((local_taskset & local_taskmask & SuperMask) == 0U)
{
if ((local_evtset & EvtWaited)== 0U)
{
UTIL_SEQ_Idle( );
}
}
UTIL_SEQ_EXIT_CRITICAL_SECTION_IDLE( );
UTIL_SEQ_PostIdle( );
/* restore the mask from UTIL_SEQ_Run() */
SuperMask = super_mask_backup;
return;
}
void UTIL_SEQ_RegTask(UTIL_SEQ_bm_t TaskId_bm, uint32_t Flags, void (*Task)( void ))
{
(void)Flags;
UTIL_SEQ_ENTER_CRITICAL_SECTION();
TaskCb[SEQ_BitPosition(TaskId_bm)] = Task;
UTIL_SEQ_EXIT_CRITICAL_SECTION();
return;
}
void UTIL_SEQ_SetTask( UTIL_SEQ_bm_t TaskId_bm , uint32_t Task_Prio )
{
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
TaskSet |= TaskId_bm;
TaskPrio[Task_Prio].priority |= TaskId_bm;
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return;
}
uint32_t UTIL_SEQ_IsSchedulableTask( UTIL_SEQ_bm_t TaskId_bm)
{
uint32_t _status;
UTIL_SEQ_bm_t local_taskset;
UTIL_SEQ_ENTER_CRITICAL_SECTION();
local_taskset = TaskSet;
_status = ((local_taskset & TaskMask & SuperMask & TaskId_bm) == TaskId_bm)? 1U: 0U;
UTIL_SEQ_EXIT_CRITICAL_SECTION();
return _status;
}
void UTIL_SEQ_PauseTask( UTIL_SEQ_bm_t TaskId_bm )
{
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
TaskMask &= (~TaskId_bm);
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return;
}
uint32_t UTIL_SEQ_IsPauseTask( UTIL_SEQ_bm_t TaskId_bm )
{
uint32_t _status;
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
_status = ((TaskMask & TaskId_bm) == TaskId_bm) ? 0u:1u;
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return _status;
}
void UTIL_SEQ_ResumeTask( UTIL_SEQ_bm_t TaskId_bm )
{
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
TaskMask |= TaskId_bm;
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return;
}
void UTIL_SEQ_SetEvt( UTIL_SEQ_bm_t EvtId_bm )
{
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
EvtSet |= EvtId_bm;
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return;
}
void UTIL_SEQ_ClrEvt( UTIL_SEQ_bm_t EvtId_bm )
{
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
EvtSet &= (~EvtId_bm);
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
return;
}
void UTIL_SEQ_WaitEvt(UTIL_SEQ_bm_t EvtId_bm)
{
UTIL_SEQ_bm_t event_waited_id_backup;
UTIL_SEQ_bm_t current_task_idx;
UTIL_SEQ_bm_t wait_task_idx;
/*
* store in local the current_task_id_bm as the global variable CurrentTaskIdx
* may be overwritten in case there are nested call of UTIL_SEQ_Run()
*/
current_task_idx = CurrentTaskIdx;
if(UTIL_SEQ_NOTASKRUNNING == CurrentTaskIdx)
{
wait_task_idx = 0u;
}
else
{
wait_task_idx = (uint32_t)1u << CurrentTaskIdx;
}
/* backup the event id that was currently waited */
event_waited_id_backup = EvtWaited;
EvtWaited = EvtId_bm;
/*
* wait for the new event
* note: that means that if the previous waited event occurs, it will not exit
* the while loop below.
* The system is waiting only for the last waited event.
* When it will go out, it will wait again from the previous one.
* It case it occurs while waiting for the second one, the while loop will exit immediately
*/
while ((EvtSet & EvtId_bm) == 0U)
{
UTIL_SEQ_EvtIdle(wait_task_idx, EvtId_bm);
}
/*
* Restore the CurrentTaskIdx that may have been modified by call of UTIL_SEQ_Run() from UTIL_SEQ_EvtIdle()
* This is required so that a second call of UTIL_SEQ_WaitEvt() in the same process pass the correct current_task_id_bm
* in the call of UTIL_SEQ_EvtIdle()
*/
CurrentTaskIdx = current_task_idx;
UTIL_SEQ_ENTER_CRITICAL_SECTION( );
EvtSet &= (~EvtId_bm);
UTIL_SEQ_EXIT_CRITICAL_SECTION( );
EvtWaited = event_waited_id_backup;
return;
}
UTIL_SEQ_bm_t UTIL_SEQ_IsEvtPend( void )
{
UTIL_SEQ_bm_t local_evtwaited = EvtWaited;
return (EvtSet & local_evtwaited);
}
__WEAK void UTIL_SEQ_EvtIdle( UTIL_SEQ_bm_t TaskId_bm, UTIL_SEQ_bm_t EvtWaited_bm )
{
(void)EvtWaited_bm;
UTIL_SEQ_Run(~TaskId_bm);
return;
}
__WEAK void UTIL_SEQ_Idle( void )
{
return;
}
__WEAK void UTIL_SEQ_PreIdle( void )
{
/*
* Unless specified by the application, there is nothing to be done
*/
return;
}
__WEAK void UTIL_SEQ_PostIdle( void )
{
/*
* Unless specified by the application, there is nothing to be done
*/
return;
}
/**
* @}
*/
/** @addtogroup SEQUENCER_Private_function
* @{
*/
#if( __CORTEX_M == 0)
const uint8_t SEQ_clz_table_4bit[16U] = { 4U, 3U, 2U, 2U, 1U, 1U, 1U, 1U, 0U, 0U, 0U, 0U, 0U, 0U, 0U, 0U };
/**
* @brief return the position of the first bit set to 1
* @param Value 32 bit value
* @retval bit position
*/
uint8_t SEQ_BitPosition(uint32_t Value)
{
uint8_t n = 0U;
uint32_t lvalue = Value;
if ((lvalue & 0xFFFF0000U) == 0U) { n = 16U; lvalue <<= 16U; }
if ((lvalue & 0xFF000000U) == 0U) { n += 8U; lvalue <<= 8U; }
if ((lvalue & 0xF0000000U) == 0U) { n += 4U; lvalue <<= 4U; }
n += SEQ_clz_table_4bit[lvalue >> (32-4)];
return (uint8_t)(31U-n);
}
#else
/**
* @brief return the position of the first bit set to 1
* @param Value 32 bit value
* @retval bit position
*/
uint8_t SEQ_BitPosition(uint32_t Value)
{
return (uint8_t)(31 -__CLZ( Value ));
}
#endif
/**
* @}
*/
/**
* @}
*/