/* | |
FreeRTOS V5.4.2 - Copyright (C) 2009 Real Time Engineers Ltd. | |
This file is part of the FreeRTOS distribution. | |
FreeRTOS is free software; you can redistribute it and/or modify it under | |
the terms of the GNU General Public License (version 2) as published by the | |
Free Software Foundation and modified by the FreeRTOS exception. | |
**NOTE** The exception to the GPL is included to allow you to distribute a | |
combined work that includes FreeRTOS without being obliged to provide the | |
source code for proprietary components outside of the FreeRTOS kernel. | |
Alternative commercial license and support terms are also available upon | |
request. See the licensing section of http://www.FreeRTOS.org for full | |
license details. | |
FreeRTOS is distributed in the hope that it will be useful, but WITHOUT | |
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | |
more details. | |
You should have received a copy of the GNU General Public License along | |
with FreeRTOS; if not, write to the Free Software Foundation, Inc., 59 | |
Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
*************************************************************************** | |
* * | |
* Looking for a quick start? Then check out the FreeRTOS eBook! * | |
* See http://www.FreeRTOS.org/Documentation for details * | |
* * | |
*************************************************************************** | |
1 tab == 4 spaces! | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
http://www.FreeRTOS.org - Documentation, latest information, license and | |
contact details. | |
http://www.SafeRTOS.com - A version that is certified for use in safety | |
critical systems. | |
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licensing and training services. | |
*/ | |
/* | |
Changes from V3.2.1 | |
+ CallReturn Depth increased from 8 to 10 levels to accomodate wizC/fedC V12. | |
Changes from V3.2.0 | |
+ TBLPTRU is now initialised to zero during the initial stack creation of a new task. This solves | |
an error on devices with more than 64kB ROM. | |
Changes from V3.0.0 | |
+ ucCriticalNesting is now initialised to 0x7F to prevent interrupts from being | |
handled before the scheduler is started. | |
Changes from V3.0.1 | |
*/ | |
/* Scheduler include files. */ | |
#include <FreeRTOS.h> | |
#include <task.h> | |
#include <malloc.h> | |
/*--------------------------------------------------------------------------- | |
* Implementation of functions defined in portable.h for the WizC PIC18 port. | |
*---------------------------------------------------------------------------*/ | |
/* | |
* We require the address of the pxCurrentTCB variable, but don't want to | |
* know any details of its type. | |
*/ | |
typedef void tskTCB; | |
extern volatile tskTCB * volatile pxCurrentTCB; | |
/* | |
* Define minimal-stack constants | |
* ----- | |
* FSR's: | |
* STATUS, WREG, BSR, PRODH, PRODL, FSR0H, FSR0L, | |
* FSR1H, FSR1L,TABLAT, (TBLPTRU), TBLPTRH, TBLPTRL, | |
* (PCLATU), PCLATH | |
* sfr's within parenthesis only on devices > 64kB | |
* ----- | |
* Call/Return stack: | |
* 2 bytes per entry on devices <= 64kB | |
* 3 bytes per entry on devices > 64kB | |
* ----- | |
* Other bytes: | |
* 2 bytes: FunctionParameter for initial taskcode | |
* 1 byte : Number of entries on call/return stack | |
* 1 byte : ucCriticalNesting | |
* 16 bytes: Free space on stack | |
*/ | |
#if _ROMSIZE > 0x8000 | |
#define portSTACK_FSR_BYTES ( 15 ) | |
#define portSTACK_CALLRETURN_ENTRY_SIZE ( 3 ) | |
#else | |
#define portSTACK_FSR_BYTES ( 13 ) | |
#define portSTACK_CALLRETURN_ENTRY_SIZE ( 2 ) | |
#endif | |
#define portSTACK_MINIMAL_CALLRETURN_DEPTH ( 10 ) | |
#define portSTACK_OTHER_BYTES ( 20 ) | |
unsigned portSHORT usCalcMinStackSize = 0; | |
/*-----------------------------------------------------------*/ | |
/* | |
* We initialise ucCriticalNesting to the middle value an | |
* unsigned char can contain. This way portENTER_CRITICAL() | |
* and portEXIT_CRITICAL() can be called without interrupts | |
* being enabled before the scheduler starts. | |
*/ | |
register unsigned portCHAR ucCriticalNesting = 0x7F; | |
/*-----------------------------------------------------------*/ | |
/* | |
* Initialise the stack of a new task. | |
* See portSAVE_CONTEXT macro for description. | |
*/ | |
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters ) | |
{ | |
unsigned portCHAR ucScratch; | |
/* | |
* Get the size of the RAMarea in page 0 used by the compiler | |
* We do this here already to avoid W-register conflicts. | |
*/ | |
_Pragma("asm") | |
movlw OVERHEADPAGE0-LOCOPTSIZE+MAXLOCOPTSIZE | |
movwf PRODL,ACCESS ; PRODL is used as temp register | |
_Pragma("asmend") | |
ucScratch = PRODL; | |
/* | |
* Place a few bytes of known values on the bottom of the stack. | |
* This is just useful for debugging. | |
*/ | |
// *pxTopOfStack-- = 0x11; | |
// *pxTopOfStack-- = 0x22; | |
// *pxTopOfStack-- = 0x33; | |
/* | |
* Simulate how the stack would look after a call to vPortYield() | |
* generated by the compiler. | |
*/ | |
/* | |
* First store the function parameters. This is where the task expects | |
* to find them when it starts running. | |
*/ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) ( (( unsigned portSHORT ) pvParameters >> 8) & 0x00ff ); | |
*pxTopOfStack-- = ( portSTACK_TYPE ) ( ( unsigned portSHORT ) pvParameters & 0x00ff ); | |
/* | |
* Next are all the registers that form part of the task context. | |
*/ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x11; /* STATUS. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x22; /* WREG. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x33; /* BSR. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x44; /* PRODH. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x55; /* PRODL. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x66; /* FSR0H. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x77; /* FSR0L. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x88; /* FSR1H. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x99; /* FSR1L. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0xAA; /* TABLAT. */ | |
#if _ROMSIZE > 0x8000 | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0x00; /* TBLPTRU. */ | |
#endif | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0xCC; /* TBLPTRH. */ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0xDD; /* TBLPTRL. */ | |
#if _ROMSIZE > 0x8000 | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0xEE; /* PCLATU. */ | |
#endif | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0xFF; /* PCLATH. */ | |
/* | |
* Next the compiler's scratchspace. | |
*/ | |
while(ucScratch-- > 0) | |
{ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0; | |
} | |
/* | |
* The only function return address so far is the address of the task entry. | |
* The order is TOSU/TOSH/TOSL. For devices > 64kB, TOSU is put on the | |
* stack, too. TOSU is always written as zero here because wizC does not allow | |
* functionpointers to point above 64kB in ROM. | |
*/ | |
#if _ROMSIZE > 0x8000 | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 0; | |
#endif | |
*pxTopOfStack-- = ( portSTACK_TYPE ) ( ( ( unsigned portSHORT ) pxCode >> 8 ) & 0x00ff ); | |
*pxTopOfStack-- = ( portSTACK_TYPE ) ( ( unsigned portSHORT ) pxCode & 0x00ff ); | |
/* | |
* Store the number of return addresses on the hardware stack. | |
* So far only the address of the task entry point. | |
*/ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) 1; | |
/* | |
* The code generated by wizC does not maintain separate | |
* stack and frame pointers. Therefore the portENTER_CRITICAL macro cannot | |
* use the stack as per other ports. Instead a variable is used to keep | |
* track of the critical section nesting. This variable has to be stored | |
* as part of the task context and is initially set to zero. | |
*/ | |
*pxTopOfStack-- = ( portSTACK_TYPE ) portNO_CRITICAL_SECTION_NESTING; | |
return pxTopOfStack; | |
} | |
/*-----------------------------------------------------------*/ | |
unsigned portSHORT usPortCALCULATE_MINIMAL_STACK_SIZE( void ) | |
{ | |
/* | |
* Fetch the size of compiler's scratchspace. | |
*/ | |
_Pragma("asm") | |
movlw OVERHEADPAGE0-LOCOPTSIZE+MAXLOCOPTSIZE | |
movlb usCalcMinStackSize>>8 | |
movwf usCalcMinStackSize,BANKED | |
_Pragma("asmend") | |
/* | |
* Add minimum needed stackspace | |
*/ | |
usCalcMinStackSize += ( portSTACK_FSR_BYTES ) | |
+ ( portSTACK_MINIMAL_CALLRETURN_DEPTH * portSTACK_CALLRETURN_ENTRY_SIZE ) | |
+ ( portSTACK_OTHER_BYTES ); | |
return(usCalcMinStackSize); | |
} | |
/*-----------------------------------------------------------*/ | |
portBASE_TYPE xPortStartScheduler( void ) | |
{ | |
extern void portSetupTick( void ); | |
/* | |
* Setup a timer for the tick ISR for the preemptive scheduler. | |
*/ | |
portSetupTick(); | |
/* | |
* Restore the context of the first task to run. | |
*/ | |
portRESTORE_CONTEXT(); | |
/* | |
* This point should never be reached during execution. | |
*/ | |
return pdTRUE; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEndScheduler( void ) | |
{ | |
/* | |
* It is unlikely that the scheduler for the PIC port will get stopped | |
* once running. When called a reset is done which is probably the | |
* most valid action. | |
*/ | |
_Pragma(asmline reset); | |
} | |
/*-----------------------------------------------------------*/ | |
/* | |
* Manual context switch. This is similar to the tick context switch, | |
* but does not increment the tick count. It must be identical to the | |
* tick context switch in how it stores the stack of a task. | |
*/ | |
void vPortYield( void ) | |
{ | |
/* | |
* Save the context of the current task. | |
*/ | |
portSAVE_CONTEXT( portINTERRUPTS_UNCHANGED ); | |
/* | |
* Switch to the highest priority task that is ready to run. | |
*/ | |
vTaskSwitchContext(); | |
/* | |
* Start executing the task we have just switched to. | |
*/ | |
portRESTORE_CONTEXT(); | |
} | |
/*-----------------------------------------------------------*/ | |
void *pvPortMalloc( unsigned portSHORT usWantedSize ) | |
{ | |
void *pvReturn; | |
vTaskSuspendAll(); | |
{ | |
pvReturn = malloc( ( malloc_t ) usWantedSize ); | |
} | |
xTaskResumeAll(); | |
return pvReturn; | |
} | |
void vPortFree( void *pv ) | |
{ | |
if( pv ) | |
{ | |
vTaskSuspendAll(); | |
{ | |
free( pv ); | |
} | |
xTaskResumeAll(); | |
} | |
} |