begriffs open source - freertos/blob - portable/MPLAB/PIC24_dsPIC/port.c

   1 /*\r
   2  * FreeRTOS Kernel V10.3.1\r
   3  * Copyright (C) 2020 Amazon.com, Inc. or its affiliates.  All Rights Reserved.\r
   4  *\r
   5  * Permission is hereby granted, free of charge, to any person obtaining a copy of\r
   6  * this software and associated documentation files (the "Software"), to deal in\r
   7  * the Software without restriction, including without limitation the rights to\r
   8  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of\r
   9  * the Software, and to permit persons to whom the Software is furnished to do so,\r
  10  * subject to the following conditions:\r
  11  *\r
  12  * The above copyright notice and this permission notice shall be included in all\r
  13  * copies or substantial portions of the Software.\r
  14  *\r
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR\r
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS\r
  17  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR\r
  18  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER\r
  19  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN\r
  20  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.\r
  21  *\r
  22  * http://www.FreeRTOS.org\r
  23  * http://aws.amazon.com/freertos\r
  24  *\r
  25  */\r
  26 \r
  27 /*\r
  28  *  Changes from V4.2.1\r
  29  *\r
  30  + Introduced the configKERNEL_INTERRUPT_PRIORITY definition.\r
  31  */\r
  32 \r
  33 /*-----------------------------------------------------------\r
  34 * Implementation of functions defined in portable.h for the PIC24 port.\r
  35 *----------------------------------------------------------*/\r
  36 \r
  37 /* Scheduler include files. */\r
  38 #include "FreeRTOS.h"\r
  39 #include "task.h"\r
  40 \r
  41 /* Hardware specifics. */\r
  42 #define portBIT_SET           1\r
  43 #define portTIMER_PRESCALE    8\r
  44 #define portINITIAL_SR        0\r
  45 \r
  46 /* Defined for backward compatability with project created prior to\r
  47  * FreeRTOS.org V4.3.0. */\r
  48 #ifndef configKERNEL_INTERRUPT_PRIORITY\r
  49     #define configKERNEL_INTERRUPT_PRIORITY    1\r
  50 #endif\r
  51 \r
  52 /* Use _T1Interrupt as the interrupt handler name if the application writer has\r
  53  * not provided their own. */\r
  54 #ifndef configTICK_INTERRUPT_HANDLER\r
  55     #define configTICK_INTERRUPT_HANDLER    _T1Interrupt\r
  56 #endif /* configTICK_INTERRUPT_HANDLER */\r
  57 \r
  58 /* The program counter is only 23 bits. */\r
  59 #define portUNUSED_PR_BITS    0x7f\r
  60 \r
  61 /* Records the nesting depth of calls to portENTER_CRITICAL(). */\r
  62 UBaseType_t uxCriticalNesting = 0xef;\r
  63 \r
  64 #if configKERNEL_INTERRUPT_PRIORITY != 1\r
  65     #error If configKERNEL_INTERRUPT_PRIORITY is not 1 then the #32 in the following macros needs changing to equal the portINTERRUPT_BITS value, which is ( configKERNEL_INTERRUPT_PRIORITY << 5 )\r
  66 #endif\r
  67 \r
  68 #if defined( __PIC24E__ ) || defined( __PIC24F__ ) || defined( __PIC24FK__ ) || defined( __PIC24H__ )\r
  69 \r
  70     #ifdef __HAS_EDS__\r
  71         #define portRESTORE_CONTEXT()                                                                                    \\r
  72     asm volatile ( "MOV _pxCurrentTCB, W0               \n"             /* Restore the stack pointer for the task. */            \\r
  73                    "MOV [W0], W15                               \n"                                                                      \\r
  74                    "POP W0                                              \n"             /* Restore the critical nesting counter for the task. */ \\r
  75                    "MOV W0, _uxCriticalNesting  \n"                                                                      \\r
  76                    "POP DSWPAG                                  \n"                                                                      \\r
  77                    "POP    DSRPAG                                       \n"                                                                  \\r
  78                    "POP CORCON                                  \n"                                                                      \\r
  79                    "POP TBLPAG                                  \n"                                                                      \\r
  80                    "POP RCOUNT                                  \n"             /* Restore the registers from the stack. */              \\r
  81                    "POP W14                                             \n"                                                                      \\r
  82                    "POP.D       W12                                             \n"                                                                  \\r
  83                    "POP.D       W10                                             \n"                                                                  \\r
  84                    "POP.D       W8                                              \n"                                                                  \\r
  85                    "POP.D       W6                                              \n"                                                                  \\r
  86                    "POP.D       W4                                              \n"                                                                  \\r
  87                    "POP.D       W2                                              \n"                                                                  \\r
  88                    "POP.D       W0                                              \n"                                                                  \\r
  89                    "POP SR                                                ");\r
  90     #else /* __HAS_EDS__ */\r
  91         #define portRESTORE_CONTEXT()                                                                                    \\r
  92     asm volatile ( "MOV _pxCurrentTCB, W0               \n"             /* Restore the stack pointer for the task. */            \\r
  93                    "MOV [W0], W15                               \n"                                                                      \\r
  94                    "POP W0                                              \n"             /* Restore the critical nesting counter for the task. */ \\r
  95                    "MOV W0, _uxCriticalNesting  \n"                                                                      \\r
  96                    "POP PSVPAG                                  \n"                                                                      \\r
  97                    "POP CORCON                                  \n"                                                                      \\r
  98                    "POP TBLPAG                                  \n"                                                                      \\r
  99                    "POP RCOUNT                                  \n"             /* Restore the registers from the stack. */              \\r
 100                    "POP W14                                             \n"                                                                      \\r
 101                    "POP.D       W12                                             \n"                                                                  \\r
 102                    "POP.D       W10                                             \n"                                                                  \\r
 103                    "POP.D       W8                                              \n"                                                                  \\r
 104                    "POP.D       W6                                              \n"                                                                  \\r
 105                    "POP.D       W4                                              \n"                                                                  \\r
 106                    "POP.D       W2                                              \n"                                                                  \\r
 107                    "POP.D       W0                                              \n"                                                                  \\r
 108                    "POP SR                                                ");\r
 109     #endif /* __HAS_EDS__ */\r
 110 #endif /* MPLAB_PIC24_PORT */\r
 111 \r
 112 #if defined( __dsPIC30F__ ) || defined( __dsPIC33F__ )\r
 113 \r
 114     #define portRESTORE_CONTEXT()                                                                                    \\r
 115     asm volatile ( "MOV _pxCurrentTCB, W0               \n"         /* Restore the stack pointer for the task. */            \\r
 116                    "MOV [W0], W15                               \n"                                                                  \\r
 117                    "POP W0                                              \n"         /* Restore the critical nesting counter for the task. */ \\r
 118                    "MOV W0, _uxCriticalNesting  \n"                                                                  \\r
 119                    "POP PSVPAG                                  \n"                                                                  \\r
 120                    "POP CORCON                                  \n"                                                                  \\r
 121                    "POP DOENDH                                  \n"                                                                  \\r
 122                    "POP DOENDL                                  \n"                                                                  \\r
 123                    "POP DOSTARTH                                \n"                                                                  \\r
 124                    "POP DOSTARTL                                \n"                                                                  \\r
 125                    "POP DCOUNT                                  \n"                                                                  \\r
 126                    "POP ACCBU                                   \n"                                                                  \\r
 127                    "POP ACCBH                                   \n"                                                                  \\r
 128                    "POP ACCBL                                   \n"                                                                  \\r
 129                    "POP ACCAU                                   \n"                                                                  \\r
 130                    "POP ACCAH                                   \n"                                                                  \\r
 131                    "POP ACCAL                                   \n"                                                                  \\r
 132                    "POP TBLPAG                                  \n"                                                                  \\r
 133                    "POP RCOUNT                                  \n"         /* Restore the registers from the stack. */              \\r
 134                    "POP W14                                             \n"                                                                  \\r
 135                    "POP.D       W12                                             \n"                                                              \\r
 136                    "POP.D       W10                                             \n"                                                              \\r
 137                    "POP.D       W8                                              \n"                                                              \\r
 138                    "POP.D       W6                                              \n"                                                              \\r
 139                    "POP.D       W4                                              \n"                                                              \\r
 140                    "POP.D       W2                                              \n"                                                              \\r
 141                    "POP.D       W0                                              \n"                                                              \\r
 142                    "POP SR                                                ");\r
 143 \r
 144 #endif /* MPLAB_DSPIC_PORT */\r
 145 \r
 146 #ifndef portRESTORE_CONTEXT\r
 147     #error Unrecognised device selected\r
 148 \r
 149 /* Note:  dsPIC parts with EDS are not supported as there is no easy way to\r
 150  * recover the hardware stacked copies for DOCOUNT, DOHIGH, DOLOW. */\r
 151 #endif\r
 152 \r
 153 /*\r
 154  * Setup the timer used to generate the tick interrupt.\r
 155  */\r
 156 void vApplicationSetupTickTimerInterrupt( void );\r
 157 \r
 158 /*\r
 159  * See header file for description.\r
 160  */\r
 161 StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,\r
 162                                      TaskFunction_t pxCode,\r
 163                                      void * pvParameters )\r
 164 {\r
 165     uint16_t          usCode;\r
 166     UBaseType_t       i;\r
 167 \r
 168     const StackType_t xInitialStack[] =\r
 169     {\r
 170         0x1111, /* W1 */\r
 171         0x2222, /* W2 */\r
 172         0x3333, /* W3 */\r
 173         0x4444, /* W4 */\r
 174         0x5555, /* W5 */\r
 175         0x6666, /* W6 */\r
 176         0x7777, /* W7 */\r
 177         0x8888, /* W8 */\r
 178         0x9999, /* W9 */\r
 179         0xaaaa, /* W10 */\r
 180         0xbbbb, /* W11 */\r
 181         0xcccc, /* W12 */\r
 182         0xdddd, /* W13 */\r
 183         0xeeee, /* W14 */\r
 184         0xcdce, /* RCOUNT */\r
 185         0xabac, /* TBLPAG */\r
 186 \r
 187         /* dsPIC specific registers. */\r
 188         #ifdef MPLAB_DSPIC_PORT\r
 189             0x0202, /* ACCAL */\r
 190             0x0303, /* ACCAH */\r
 191             0x0404, /* ACCAU */\r
 192             0x0505, /* ACCBL */\r
 193             0x0606, /* ACCBH */\r
 194             0x0707, /* ACCBU */\r
 195             0x0808, /* DCOUNT */\r
 196             0x090a, /* DOSTARTL */\r
 197             0x1010, /* DOSTARTH */\r
 198             0x1110, /* DOENDL */\r
 199             0x1212, /* DOENDH */\r
 200         #endif /* ifdef MPLAB_DSPIC_PORT */\r
 201     };\r
 202 \r
 203     /* Setup the stack as if a yield had occurred.\r
 204      *\r
 205      * Save the low bytes of the program counter. */\r
 206     usCode            = ( uint16_t ) pxCode;\r
 207     *pxTopOfStack     = ( StackType_t ) usCode;\r
 208     pxTopOfStack++;\r
 209 \r
 210     /* Save the high byte of the program counter.  This will always be zero\r
 211      * here as it is passed in a 16bit pointer.  If the address is greater than\r
 212      * 16 bits then the pointer will point to a jump table. */\r
 213     *pxTopOfStack     = ( StackType_t ) 0;\r
 214     pxTopOfStack++;\r
 215 \r
 216     /* Status register with interrupts enabled. */\r
 217     *pxTopOfStack     = portINITIAL_SR;\r
 218     pxTopOfStack++;\r
 219 \r
 220     /* Parameters are passed in W0. */\r
 221     *pxTopOfStack     = ( StackType_t ) pvParameters;\r
 222     pxTopOfStack++;\r
 223 \r
 224     for( i = 0; i < ( sizeof( xInitialStack ) / sizeof( StackType_t ) ); i++ )\r
 225     {\r
 226         *pxTopOfStack = xInitialStack[ i ];\r
 227         pxTopOfStack++;\r
 228     }\r
 229 \r
 230     *pxTopOfStack     = CORCON;\r
 231     pxTopOfStack++;\r
 232 \r
 233     #if defined( __HAS_EDS__ )\r
 234         *pxTopOfStack = DSRPAG;\r
 235         pxTopOfStack++;\r
 236         *pxTopOfStack = DSWPAG;\r
 237         pxTopOfStack++;\r
 238     #else /* __HAS_EDS__ */\r
 239         *pxTopOfStack = PSVPAG;\r
 240         pxTopOfStack++;\r
 241     #endif /* __HAS_EDS__ */\r
 242 \r
 243     /* Finally the critical nesting depth. */\r
 244     *pxTopOfStack     = 0x00;\r
 245     pxTopOfStack++;\r
 246 \r
 247     return pxTopOfStack;\r
 248 }\r
 249 /*-----------------------------------------------------------*/\r
 250 \r
 251 BaseType_t xPortStartScheduler( void )\r
 252 {\r
 253     /* Setup a timer for the tick ISR. */\r
 254     vApplicationSetupTickTimerInterrupt();\r
 255 \r
 256     /* Restore the context of the first task to run. */\r
 257     portRESTORE_CONTEXT();\r
 258 \r
 259     /* Simulate the end of the yield function. */\r
 260     asm volatile ( "return" );\r
 261 \r
 262     /* Should not reach here. */\r
 263     return pdTRUE;\r
 264 }\r
 265 /*-----------------------------------------------------------*/\r
 266 \r
 267 void vPortEndScheduler( void )\r
 268 {\r
 269     /* Not implemented in ports where there is nothing to return to.\r
 270      * Artificially force an assert. */\r
 271     configASSERT( uxCriticalNesting == 1000UL );\r
 272 }\r
 273 /*-----------------------------------------------------------*/\r
 274 \r
 275 /*\r
 276  * Setup a timer for a regular tick.\r
 277  */\r
 278 __attribute__( ( weak ) ) void vApplicationSetupTickTimerInterrupt( void )\r
 279 {\r
 280     const uint32_t ulCompareMatch = ( ( configCPU_CLOCK_HZ / portTIMER_PRESCALE ) / configTICK_RATE_HZ ) - 1;\r
 281 \r
 282     /* Prescale of 8. */\r
 283     T1CON            = 0;\r
 284     TMR1             = 0;\r
 285 \r
 286     PR1              = ( uint16_t ) ulCompareMatch;\r
 287 \r
 288     /* Setup timer 1 interrupt priority. */\r
 289     IPC0bits.T1IP    = configKERNEL_INTERRUPT_PRIORITY;\r
 290 \r
 291     /* Clear the interrupt as a starting condition. */\r
 292     IFS0bits.T1IF    = 0;\r
 293 \r
 294     /* Enable the interrupt. */\r
 295     IEC0bits.T1IE    = 1;\r
 296 \r
 297     /* Setup the prescale value. */\r
 298     T1CONbits.TCKPS0 = 1;\r
 299     T1CONbits.TCKPS1 = 0;\r
 300 \r
 301     /* Start the timer. */\r
 302     T1CONbits.TON    = 1;\r
 303 }\r
 304 /*-----------------------------------------------------------*/\r
 305 \r
 306 void vPortEnterCritical( void )\r
 307 {\r
 308     portDISABLE_INTERRUPTS();\r
 309     uxCriticalNesting++;\r
 310 }\r
 311 /*-----------------------------------------------------------*/\r
 312 \r
 313 void vPortExitCritical( void )\r
 314 {\r
 315     configASSERT( uxCriticalNesting );\r
 316     uxCriticalNesting--;\r
 317 \r
 318     if( uxCriticalNesting == 0 )\r
 319     {\r
 320         portENABLE_INTERRUPTS();\r
 321     }\r
 322 }\r
 323 /*-----------------------------------------------------------*/\r
 324 \r
 325 void __attribute__( ( __interrupt__, auto_psv ) ) configTICK_INTERRUPT_HANDLER( void )\r
 326 {\r
 327     /* Clear the timer interrupt. */\r
 328     IFS0bits.T1IF = 0;\r
 329 \r
 330     if( xTaskIncrementTick() != pdFALSE )\r
 331     {\r
 332         portYIELD();\r
 333     }\r
 334 }\r