git.sur5r.net Git - freertos/blob - FreeRTOS/Source/portable/Paradigm/Tern_EE/large_untested/portasm.h

   1 /*\r
   2  * FreeRTOS Kernel V10.0.1\r
   3  * Copyright (C) 2017 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  * 1 tab == 4 spaces!\r
  26  */\r
  27 \r
  28 typedef void TCB_t;\r
  29 extern volatile TCB_t * volatile pxCurrentTCB;\r
  30 extern void vTaskSwitchContext( void );\r
  31 \r
  32 /*\r
  33  * Saves the stack pointer for one task into its TCB, calls\r
  34  * vTaskSwitchContext() to update the TCB being used, then restores the stack\r
  35  * from the new TCB read to run the task.\r
  36  */\r
  37 void portSWITCH_CONTEXT( void );\r
  38 \r
  39 /*\r
  40  * Load the stack pointer from the TCB of the task which is going to be first\r
  41  * to execute.  Then force an IRET so the registers and IP are popped off the\r
  42  * stack.\r
  43  */\r
  44 void portFIRST_CONTEXT( void );\r
  45 \r
  46 #define portSWITCH_CONTEXT()                                                                             \\r
  47                                                 asm { mov       ax, seg pxCurrentTCB            } \\r
  48                                                         asm { mov       ds, ax                                          }  \\r
  49                                                         asm { les       bx, pxCurrentTCB                        }       /* Save the stack pointer into the TCB. */    \\r
  50                                                         asm { mov       es:0x2[ bx ], ss                        }   \\r
  51                                                         asm { mov       es:[ bx ], sp                           }   \\r
  52                                                         asm { call  far ptr vTaskSwitchContext  }       /* Perform the switch. */   \\r
  53                                                         asm { mov       ax, seg pxCurrentTCB            }       /* Restore the stack pointer from the TCB. */  \\r
  54                                                         asm { mov       ds, ax                                          }   \\r
  55                                                         asm { les       bx, dword ptr pxCurrentTCB      }   \\r
  56                                                         asm { mov       ss, es:[ bx + 2 ]                       }      \\r
  57                                                         asm { mov       sp, es:[ bx ]                           }\r
  58 \r
  59 #define portFIRST_CONTEXT()                                                                                             \\r
  60                                                         asm { mov       ax, seg pxCurrentTCB            }       \\r
  61                                                         asm { mov       ds, ax                                          }       \\r
  62                                                         asm { les       bx, dword ptr pxCurrentTCB      }       \\r
  63                                                         asm { mov       ss, es:[ bx + 2 ]                       }       \\r
  64                                                         asm { mov       sp, es:[ bx ]                           }       \\r
  65                                                         asm { pop       bp                                                      }       \\r
  66                                                         asm { pop       di                                                      }       \\r
  67                                                         asm { pop       si                                                      }       \\r
  68                                                         asm { pop       ds                                                      }       \\r
  69                                                         asm { pop       es                                                      }       \\r
  70                                                         asm { pop       dx                                                      }       \\r
  71                                                         asm { pop       cx                                                      }       \\r
  72                                                         asm { pop       bx                                                      }       \\r
  73                                                         asm { pop       ax                                                      }       \\r
  74                                                         asm { iret                                                              }\r
  75 \r
  76 \r