portable/ThirdParty/GCC/ARC_v1/port.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2020 Synopsys, Inc. or its affiliates.  All Rights Reserved.
  *
  * SPDX-License-Identifier: MIT
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy of
  * this software and associated documentation files (the "Software"), to deal in
  * the Software without restriction, including without limitation the rights to
  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
  * the Software, and to permit persons to whom the Software is furnished to do so,
  * subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in all
  * copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  *
  * https://www.FreeRTOS.org
  * https://github.com/FreeRTOS
  *
  */

 /*
  * Implementation of functions defined in portable.h
  */

 #include "FreeRTOS.h"
 #include "task.h"
 #include "FreeRTOSConfig.h"

 #include "arc/arc_exception.h"
 #include "arc/arc_timer.h"
 #include "board.h"

 #include "arc_freertos_exceptions.h"

 volatile unsigned int ulCriticalNesting = 999UL;
 volatile unsigned int context_switch_reqflg; /* task context switch request flag in exceptions and interrupts handling */

 /**
  * \var exc_nest_count
  * \brief the counter for exc/int processing, =0 no int/exc
  * >1 in int/exc processing
  * @}
  */
 uint32_t exc_nest_count;
 /* --------------------------------------------------------------------------*/

 /**
  * @brief kernel tick interrupt handler of freertos
  */
 /* ----------------------------------------------------------------------------*/
 static void vKernelTick( void * ptr )
 {
     /* clear timer interrupt */
     arc_timer_int_clear( BOARD_OS_TIMER_ID );
     board_timer_update( configTICK_RATE_HZ );

     if( xTaskIncrementTick() )
     {
         portYIELD_FROM_ISR(); /* need to make task switch */
     }
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief  setup freertos kernel tick
  */
 /* ----------------------------------------------------------------------------*/
 static void prvSetupTimerInterrupt( void )
 {
     unsigned int cyc = configCPU_CLOCK_HZ / configTICK_RATE_HZ;

     int_disable( BOARD_OS_TIMER_INTNO ); /* disable os timer interrupt */
     arc_timer_stop( BOARD_OS_TIMER_ID );
     arc_timer_start( BOARD_OS_TIMER_ID, TIMER_CTRL_IE | TIMER_CTRL_NH, cyc );

     int_handler_install( BOARD_OS_TIMER_INTNO, ( INT_HANDLER_T ) vKernelTick );
     int_pri_set( BOARD_OS_TIMER_INTNO, INT_PRI_MIN );
     int_enable( BOARD_OS_TIMER_INTNO );
 }

 /*
  * Setup the stack of a new task so it is ready to be placed under the
  * scheduler control.  The registers have to be placed on the stack in
  * the order that the port expects to find them.
  *
  * For ARC, task context switch is implemented with the help of SWI exception
  * It's not efficient but simple.
  *
  */
 StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
                                      TaskFunction_t pxCode,
                                      void * pvParameters )
 {
     /* To ensure asserts in tasks.c don't fail, although in this case the assert
      * is not really required. */
     pxTopOfStack--;

     /* Setup the initial stack of the task.  The stack is set exactly as
      * expected by the portRESTORE_CONTEXT() macro. */

     /* When the task starts is will expect to find the function parameter in
      * R0. */
     *pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */

     pxTopOfStack--;
     *pxTopOfStack = ( StackType_t ) pxCode; /* function body */

     /* PC */
     pxTopOfStack--;
     *pxTopOfStack = ( StackType_t ) start_r; /* dispatch return address */

     pxTopOfStack--;
     *pxTopOfStack = ( StackType_t ) portNO_CRITICAL_NESTING;
     return pxTopOfStack;
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief  start the freertos scheduler, go to the first task
  *
  * @returns
  */
 /* ----------------------------------------------------------------------------*/
 BaseType_t xPortStartScheduler( void )
 {
     /* Start the timer that generates the tick ISR. */
     prvSetupTimerInterrupt();
     start_dispatch();

     /* Should not get here! */
     return 0;
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief
  */
 /* ----------------------------------------------------------------------------*/
 void vPortEndScheduler( void )
 {
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief  generate a task switch request in ISR
  */
 /* ----------------------------------------------------------------------------*/
 void vPortYieldFromIsr( void )
 {
     unsigned int status32;

     status32 = cpu_lock_save();
     context_switch_reqflg = true;
     cpu_unlock_restore( status32 );
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief
  */
 /* ----------------------------------------------------------------------------*/
 void vPortYield( void )
 {
     unsigned int status32;

     status32 = cpu_lock_save();
     dispatch();
     cpu_unlock_restore( status32 );
 }

 /* --------------------------------------------------------------------------*/

 /**
  * @brief
  */
 /* ----------------------------------------------------------------------------*/
 void vPortEndTask( void )
 {
     #if ( INCLUDE_vTaskDelete == 1 )
         vTaskDelete( NULL ); /* Delete task itself */
     #endif

     while( 1 ) /* Yield to other task */
     {
         vPortYield();
     }
 }

 #if ARC_FEATURE_STACK_CHECK

 /*
  * !!! Note !!!
  * This a trick!!!
  * It's a copy from task.c. We need to konw the definition of TCB for the purpose of hardware
  * stack check. Pls don't forget to update it when FreeRTOS is updated.
  */
     typedef struct tskTaskControlBlock       /* The old naming convention is used to prevent breaking kernel aware debuggers. */
     {
         volatile StackType_t * pxTopOfStack; /*< Points to the location of the last item placed on the tasks stack.  THIS MUST BE THE FIRST MEMBER OF THE TCB STRUCT. */

         #if ( portUSING_MPU_WRAPPERS == 1 )
             xMPU_SETTINGS xMPUSettings;     /*< The MPU settings are defined as part of the port layer.  THIS MUST BE THE SECOND MEMBER OF THE TCB STRUCT. */
         #endif

         ListItem_t xStateListItem;                  /*< The list that the state list item of a task is reference from denotes the state of that task (Ready, Blocked, Suspended ). */
         ListItem_t xEventListItem;                  /*< Used to reference a task from an event list. */
         UBaseType_t uxPriority;                     /*< The priority of the task.  0 is the lowest priority. */
         StackType_t * pxStack;                      /*< Points to the start of the stack. */
         char pcTaskName[ configMAX_TASK_NAME_LEN ]; /*< Descriptive name given to the task when created.  Facilitates debugging only. */ /*lint !e971 Unqualified char types are allowed for strings and single characters only. */

         #if ( ( portSTACK_GROWTH > 0 ) || ( configRECORD_STACK_HIGH_ADDRESS == 1 ) )
             StackType_t * pxEndOfStack;     /*< Points to the highest valid address for the stack. */
         #endif

         #if ( portCRITICAL_NESTING_IN_TCB == 1 )
             UBaseType_t uxCriticalNesting;  /*< Holds the critical section nesting depth for ports that do not maintain their own count in the port layer. */
         #endif

         #if ( configUSE_TRACE_FACILITY == 1 )
             UBaseType_t uxTCBNumber;        /*< Stores a number that increments each time a TCB is created.  It allows debuggers to determine when a task has been deleted and then recreated. */
             UBaseType_t uxTaskNumber;       /*< Stores a number specifically for use by third party trace code. */
         #endif

         #if ( configUSE_MUTEXES == 1 )
             UBaseType_t uxBasePriority;     /*< The priority last assigned to the task - used by the priority inheritance mechanism. */
             UBaseType_t uxMutexesHeld;
         #endif

         #if ( configUSE_APPLICATION_TASK_TAG == 1 )
             TaskHookFunction_t pxTaskTag;
         #endif

         #if ( configNUM_THREAD_LOCAL_STORAGE_POINTERS > 0 )
             void * pvThreadLocalStoragePointers[ configNUM_THREAD_LOCAL_STORAGE_POINTERS ];
         #endif

         #if ( configGENERATE_RUN_TIME_STATS == 1 )
             uint32_t ulRunTimeCounter;      /*< Stores the amount of time the task has spent in the Running state. */
         #endif

         #if ( configUSE_NEWLIB_REENTRANT == 1 )

             /* Allocate a Newlib reent structure that is specific to this task.
              * Note Newlib support has been included by popular demand, but is not
              * used by the FreeRTOS maintainers themselves.  FreeRTOS is not
              * responsible for resulting newlib operation.  User must be familiar with
              * newlib and must provide system-wide implementations of the necessary
              * stubs. Be warned that (at the time of writing) the current newlib design
              * implements a system-wide malloc() that must be provided with locks. */
             struct  _reent xNewLib_reent;
         #endif

         #if ( configUSE_TASK_NOTIFICATIONS == 1 )
             volatile uint32_t ulNotifiedValue;
             volatile uint8_t ucNotifyState;
         #endif

         /* See the comments above the definition of
          * tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE. */
         #if ( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 ) /*lint !e731 !e9029 Macro has been consolidated for readability reasons. */
             uint8_t ucStaticallyAllocated;                     /*< Set to pdTRUE if the task is a statically allocated to ensure no attempt is made to free the memory. */
         #endif

         #if ( INCLUDE_xTaskAbortDelay == 1 )
             uint8_t ucDelayAborted;
         #endif

         #if ( configUSE_POSIX_ERRNO == 1 )
             int iTaskErrno;
         #endif
     } tskTCB;


     void vPortSetStackCheck( TaskHandle_t old,
                              TaskHandle_t new )
     {
         if( new != NULL )
         {
             arc_aux_write( AUX_USTACK_BASE, ( uint32_t ) ( new->pxEndOfStack ) );
             arc_aux_write( AUX_USTACK_TOP, ( uint32_t ) ( new->pxStack ) );
         }
     }
 #endif /* if ARC_FEATURE_STACK_CHECK */
	/*
	* FreeRTOS Kernel <DEVELOPMENT BRANCH>
	* Copyright (C) 2020 Synopsys, Inc. or its affiliates. All Rights Reserved.
	*
	* SPDX-License-Identifier: MIT
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy of
	* this software and associated documentation files (the "Software"), to deal in
	* the Software without restriction, including without limitation the rights to
	* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
	* the Software, and to permit persons to whom the Software is furnished to do so,
	* subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in all
	* copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
	* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
	* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
	* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
	*
	* https://www.FreeRTOS.org
	* https://github.com/FreeRTOS
	*
	*/

	/*
	* Implementation of functions defined in portable.h
	*/

	#include "FreeRTOS.h"
	#include "task.h"
	#include "FreeRTOSConfig.h"

	#include "arc/arc_exception.h"
	#include "arc/arc_timer.h"
	#include "board.h"

	#include "arc_freertos_exceptions.h"

	volatile unsigned int ulCriticalNesting = 999UL;
	volatile unsigned int context_switch_reqflg; /* task context switch request flag in exceptions and interrupts handling */

	/**
	* \var exc_nest_count
	* \brief the counter for exc/int processing, =0 no int/exc
	* >1 in int/exc processing
	* @}
	*/
	uint32_t exc_nest_count;
	/* --------------------------------------------------------------------------*/

	/**
	* @brief kernel tick interrupt handler of freertos
	*/
	/* ----------------------------------------------------------------------------*/
	static void vKernelTick( void * ptr )
	{
	/* clear timer interrupt */
	arc_timer_int_clear( BOARD_OS_TIMER_ID );
	board_timer_update( configTICK_RATE_HZ );

	if( xTaskIncrementTick() )
	{
	portYIELD_FROM_ISR(); /* need to make task switch */
	}
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief setup freertos kernel tick
	*/
	/* ----------------------------------------------------------------------------*/
	static void prvSetupTimerInterrupt( void )
	{
	unsigned int cyc = configCPU_CLOCK_HZ / configTICK_RATE_HZ;

	int_disable( BOARD_OS_TIMER_INTNO ); /* disable os timer interrupt */
	arc_timer_stop( BOARD_OS_TIMER_ID );
	arc_timer_start( BOARD_OS_TIMER_ID, TIMER_CTRL_IE \| TIMER_CTRL_NH, cyc );

	int_handler_install( BOARD_OS_TIMER_INTNO, ( INT_HANDLER_T ) vKernelTick );
	int_pri_set( BOARD_OS_TIMER_INTNO, INT_PRI_MIN );
	int_enable( BOARD_OS_TIMER_INTNO );
	}

	/*
	* Setup the stack of a new task so it is ready to be placed under the
	* scheduler control. The registers have to be placed on the stack in
	* the order that the port expects to find them.
	*
	* For ARC, task context switch is implemented with the help of SWI exception
	* It's not efficient but simple.
	*
	*/
	StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
	TaskFunction_t pxCode,
	void * pvParameters )
	{
	/* To ensure asserts in tasks.c don't fail, although in this case the assert
	* is not really required. */
	pxTopOfStack--;

	/* Setup the initial stack of the task. The stack is set exactly as
	* expected by the portRESTORE_CONTEXT() macro. */

	/* When the task starts is will expect to find the function parameter in
	* R0. */
	pxTopOfStack = ( StackType_t ) pvParameters; / R0 */

	pxTopOfStack--;
	pxTopOfStack = ( StackType_t ) pxCode; / function body */

	/* PC */
	pxTopOfStack--;
	pxTopOfStack = ( StackType_t ) start_r; / dispatch return address */

	pxTopOfStack--;
	*pxTopOfStack = ( StackType_t ) portNO_CRITICAL_NESTING;
	return pxTopOfStack;
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief start the freertos scheduler, go to the first task
	*
	* @returns
	*/
	/* ----------------------------------------------------------------------------*/
	BaseType_t xPortStartScheduler( void )
	{
	/* Start the timer that generates the tick ISR. */
	prvSetupTimerInterrupt();
	start_dispatch();

	/* Should not get here! */
	return 0;
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief
	*/
	/* ----------------------------------------------------------------------------*/
	void vPortEndScheduler( void )
	{
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief generate a task switch request in ISR
	*/
	/* ----------------------------------------------------------------------------*/
	void vPortYieldFromIsr( void )
	{
	unsigned int status32;

	status32 = cpu_lock_save();
	context_switch_reqflg = true;
	cpu_unlock_restore( status32 );
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief
	*/
	/* ----------------------------------------------------------------------------*/
	void vPortYield( void )
	{
	unsigned int status32;

	status32 = cpu_lock_save();
	dispatch();
	cpu_unlock_restore( status32 );
	}

	/* --------------------------------------------------------------------------*/

	/**
	* @brief
	*/
	/* ----------------------------------------------------------------------------*/
	void vPortEndTask( void )
	{
	#if ( INCLUDE_vTaskDelete == 1 )
	vTaskDelete( NULL ); /* Delete task itself */
	#endif

	while( 1 ) /* Yield to other task */
	{
	vPortYield();
	}
	}

	#if ARC_FEATURE_STACK_CHECK

	/*
	* !!! Note !!!
	* This a trick!!!
	* It's a copy from task.c. We need to konw the definition of TCB for the purpose of hardware
	* stack check. Pls don't forget to update it when FreeRTOS is updated.
	*/
	typedef struct tskTaskControlBlock /* The old naming convention is used to prevent breaking kernel aware debuggers. */
	{
	volatile StackType_t * pxTopOfStack; /< Points to the location of the last item placed on the tasks stack. THIS MUST BE THE FIRST MEMBER OF THE TCB STRUCT. /

	#if ( portUSING_MPU_WRAPPERS == 1 )
	xMPU_SETTINGS xMPUSettings; /< The MPU settings are defined as part of the port layer. THIS MUST BE THE SECOND MEMBER OF THE TCB STRUCT. /
	#endif

	ListItem_t xStateListItem; /< The list that the state list item of a task is reference from denotes the state of that task (Ready, Blocked, Suspended ). /
	ListItem_t xEventListItem; /< Used to reference a task from an event list. /
	UBaseType_t uxPriority; /< The priority of the task. 0 is the lowest priority. /
	StackType_t * pxStack; /< Points to the start of the stack. /
	char pcTaskName[ configMAX_TASK_NAME_LEN ]; /< Descriptive name given to the task when created. Facilitates debugging only. / /lint !e971 Unqualified char types are allowed for strings and single characters only. /

	#if ( ( portSTACK_GROWTH > 0 ) \|\| ( configRECORD_STACK_HIGH_ADDRESS == 1 ) )
	StackType_t * pxEndOfStack; /< Points to the highest valid address for the stack. /
	#endif

	#if ( portCRITICAL_NESTING_IN_TCB == 1 )
	UBaseType_t uxCriticalNesting; /< Holds the critical section nesting depth for ports that do not maintain their own count in the port layer. /
	#endif

	#if ( configUSE_TRACE_FACILITY == 1 )
	UBaseType_t uxTCBNumber; /< Stores a number that increments each time a TCB is created. It allows debuggers to determine when a task has been deleted and then recreated. /
	UBaseType_t uxTaskNumber; /< Stores a number specifically for use by third party trace code. /
	#endif

	#if ( configUSE_MUTEXES == 1 )
	UBaseType_t uxBasePriority; /< The priority last assigned to the task - used by the priority inheritance mechanism. /
	UBaseType_t uxMutexesHeld;
	#endif

	#if ( configUSE_APPLICATION_TASK_TAG == 1 )
	TaskHookFunction_t pxTaskTag;
	#endif

	#if ( configNUM_THREAD_LOCAL_STORAGE_POINTERS > 0 )
	void * pvThreadLocalStoragePointers[ configNUM_THREAD_LOCAL_STORAGE_POINTERS ];
	#endif

	#if ( configGENERATE_RUN_TIME_STATS == 1 )
	uint32_t ulRunTimeCounter; /< Stores the amount of time the task has spent in the Running state. /
	#endif

	#if ( configUSE_NEWLIB_REENTRANT == 1 )

	/* Allocate a Newlib reent structure that is specific to this task.
	* Note Newlib support has been included by popular demand, but is not
	* used by the FreeRTOS maintainers themselves. FreeRTOS is not
	* responsible for resulting newlib operation. User must be familiar with
	* newlib and must provide system-wide implementations of the necessary
	* stubs. Be warned that (at the time of writing) the current newlib design
	* implements a system-wide malloc() that must be provided with locks. */
	struct _reent xNewLib_reent;
	#endif

	#if ( configUSE_TASK_NOTIFICATIONS == 1 )
	volatile uint32_t ulNotifiedValue;
	volatile uint8_t ucNotifyState;
	#endif

	/* See the comments above the definition of
	* tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE. */
	#if ( tskSTATIC_AND_DYNAMIC_ALLOCATION_POSSIBLE != 0 ) /lint !e731 !e9029 Macro has been consolidated for readability reasons. /
	uint8_t ucStaticallyAllocated; /< Set to pdTRUE if the task is a statically allocated to ensure no attempt is made to free the memory. /
	#endif

	#if ( INCLUDE_xTaskAbortDelay == 1 )
	uint8_t ucDelayAborted;
	#endif

	#if ( configUSE_POSIX_ERRNO == 1 )
	int iTaskErrno;
	#endif
	} tskTCB;


	void vPortSetStackCheck( TaskHandle_t old,
	TaskHandle_t new )
	{
	if( new != NULL )
	{
	arc_aux_write( AUX_USTACK_BASE, ( uint32_t ) ( new->pxEndOfStack ) );
	arc_aux_write( AUX_USTACK_TOP, ( uint32_t ) ( new->pxStack ) );
	}
	}
	#endif /* if ARC_FEATURE_STACK_CHECK */