diff options
Diffstat (limited to 'ao_task.c')
| -rw-r--r-- | ao_task.c | 224 |
1 files changed, 0 insertions, 224 deletions
diff --git a/ao_task.c b/ao_task.c deleted file mode 100644 index 06c279e9..00000000 --- a/ao_task.c +++ /dev/null @@ -1,224 +0,0 @@ -/* - * Copyright © 2009 Keith Packard <keithp@keithp.com> - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; version 2 of the License. - * - * This program 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 this program; if not, write to the Free Software Foundation, Inc., - * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. - */ - -#include "ao.h" - -#define AO_NO_TASK_INDEX 0xff - -__xdata struct ao_task * __xdata ao_tasks[AO_NUM_TASKS]; -__data uint8_t ao_num_tasks; -__data uint8_t ao_cur_task_index; -__xdata struct ao_task *__data ao_cur_task; - -void -ao_add_task(__xdata struct ao_task * task, void (*start)(void), __code char *name) __reentrant -{ - uint8_t __xdata *stack; - if (ao_num_tasks == AO_NUM_TASKS) - ao_panic(AO_PANIC_NO_TASK); - ao_tasks[ao_num_tasks++] = task; - task->task_id = ao_num_tasks; - task->name = name; - /* - * Construct a stack frame so that it will 'return' - * to the start of the task - */ - stack = task->stack; - - *stack++ = ((uint16_t) start); - *stack++ = ((uint16_t) start) >> 8; - - /* and the stuff saved by ao_switch */ - *stack++ = 0; /* acc */ - *stack++ = 0x80; /* IE */ - *stack++ = 0; /* DPL */ - *stack++ = 0; /* DPH */ - *stack++ = 0; /* B */ - *stack++ = 0; /* R2 */ - *stack++ = 0; /* R3 */ - *stack++ = 0; /* R4 */ - *stack++ = 0; /* R5 */ - *stack++ = 0; /* R6 */ - *stack++ = 0; /* R7 */ - *stack++ = 0; /* R0 */ - *stack++ = 0; /* R1 */ - *stack++ = 0; /* PSW */ - *stack++ = 0; /* BP */ - task->stack_count = stack - task->stack; - task->wchan = NULL; -} - -/* Task switching function. This must not use any stack variables */ -void -ao_yield(void) _naked -{ - - /* Save current context */ - _asm - /* Push ACC first, as when restoring the context it must be restored - * last (it is used to set the IE register). */ - push ACC - /* Store the IE register then enable interrupts. */ - push _IEN0 - setb _EA - push DPL - push DPH - push b - push ar2 - push ar3 - push ar4 - push ar5 - push ar6 - push ar7 - push ar0 - push ar1 - push PSW - _endasm; - PSW = 0; - _asm - push _bp - _endasm; - - if (ao_cur_task_index != AO_NO_TASK_INDEX) - { - uint8_t stack_len; - __data uint8_t *stack_ptr; - __xdata uint8_t *save_ptr; - /* Save the current stack */ - stack_len = SP - (AO_STACK_START - 1); - ao_cur_task->stack_count = stack_len; - stack_ptr = (uint8_t __data *) AO_STACK_START; - save_ptr = (uint8_t __xdata *) ao_cur_task->stack; - do - *save_ptr++ = *stack_ptr++; - while (--stack_len); - } - - /* Empty the stack; might as well let interrupts have the whole thing */ - SP = AO_STACK_START - 1; - - /* Find a task to run. If there isn't any runnable task, - * this loop will run forever, which is just fine - */ - { - __pdata uint8_t ao_next_task_index = ao_cur_task_index; - for (;;) { - ++ao_next_task_index; - if (ao_next_task_index == ao_num_tasks) - ao_next_task_index = 0; - - ao_cur_task = ao_tasks[ao_next_task_index]; - if (ao_cur_task->wchan == NULL) { - ao_cur_task_index = ao_next_task_index; - break; - } - - /* Enter lower power mode when there isn't anything to do */ - if (ao_next_task_index == ao_cur_task_index) - PCON = PCON_IDLE; - } - } - - { - uint8_t stack_len; - __data uint8_t *stack_ptr; - __xdata uint8_t *save_ptr; - - /* Restore the old stack */ - stack_len = ao_cur_task->stack_count; - SP = AO_STACK_START - 1 + stack_len; - - stack_ptr = (uint8_t __data *) AO_STACK_START; - save_ptr = (uint8_t __xdata *) ao_cur_task->stack; - do - *stack_ptr++ = *save_ptr++; - while (--stack_len); - } - - _asm - pop _bp - pop PSW - pop ar1 - pop ar0 - pop ar7 - pop ar6 - pop ar5 - pop ar4 - pop ar3 - pop ar2 - pop b - pop DPH - pop DPL - /* The next byte of the stack is the IE register. Only the global - enable bit forms part of the task context. Pop off the IE then set - the global enable bit to match that of the stored IE register. */ - pop ACC - JB ACC.7,0098$ - CLR _EA - LJMP 0099$ - 0098$: - SETB _EA - 0099$: - /* Finally pop off the ACC, which was the first register saved. */ - pop ACC - ret - _endasm; -} - -void -ao_sleep(__xdata void *wchan) -{ - __critical { - ao_cur_task->wchan = wchan; - } - ao_yield(); -} - -void -ao_wakeup(__xdata void *wchan) -{ - uint8_t i; - - for (i = 0; i < ao_num_tasks; i++) - if (ao_tasks[i]->wchan == wchan) - ao_tasks[i]->wchan = NULL; -} - -void -ao_task_info(void) -{ - uint8_t i; - uint8_t pc_loc; - __xdata struct ao_task *task; - - for (i = 0; i < ao_num_tasks; i++) { - task = ao_tasks[i]; - pc_loc = task->stack_count - 17; - printf("%12s: wchan %04x pc %04x\n", - task->name, - (int16_t) task->wchan, - (task->stack[pc_loc]) | (task->stack[pc_loc+1] << 8)); - } -} - -void -ao_start_scheduler(void) -{ - ao_cur_task_index = AO_NO_TASK_INDEX; - ao_cur_task = NULL; - ao_yield(); -} |