altos: Make stm-flash capable of switching to application
[fw/altos] / src / core / ao_task.c
index 910f158785fbf894dc10415d2c8bce5cfdc1352e..0aad650898d9c54dddca6d53e6fa2c799aec89d8 100644 (file)
  * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
  */
 
-#include "ao.h"
+#include <ao.h>
+#include <ao_task.h>
+#if HAS_SAMPLE_PROFILE
+#include <ao_sample_profile.h>
+#endif
+#if HAS_STACK_GUARD
+#include <ao_mpu.h>
+#endif
+
+#define DEBUG  0
 
 #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;
 
+#if !HAS_TASK_QUEUE
+static __data uint8_t ao_cur_task_index;
+#endif
+
 #ifdef ao_arch_task_globals
 ao_arch_task_globals
 #endif
 
+#define AO_CHECK_STACK 0
+
+#if AO_CHECK_STACK
+static uint8_t in_yield;
+
+static inline void ao_check_stack(void) {
+       uint8_t q;
+       if (!in_yield && ao_cur_task && &q < &ao_cur_task->stack[0])
+               ao_panic(AO_PANIC_STACK);
+}
+#else
+#define ao_check_stack()
+#endif
+
+#if HAS_TASK_QUEUE
+
+#define SLEEP_HASH_SIZE        17
+
+static struct ao_list  run_queue;
+static struct ao_list  alarm_queue;
+static struct ao_list  sleep_queue[SLEEP_HASH_SIZE];
+
+static void
+ao_task_to_run_queue(struct ao_task *task)
+{
+       ao_list_del(&task->queue);
+       ao_list_append(&task->queue, &run_queue);
+}
+
+static struct ao_list *
+ao_task_sleep_queue(void *wchan)
+{
+       return &sleep_queue[(uintptr_t) wchan % SLEEP_HASH_SIZE];
+}
+
+static void
+ao_task_to_sleep_queue(struct ao_task *task, void *wchan)
+{
+       ao_list_del(&task->queue);
+       ao_list_append(&task->queue, ao_task_sleep_queue(wchan));
+}
+
+#if DEBUG
+static void
+ao_task_validate_alarm_queue(void)
+{
+       struct ao_task  *alarm, *prev = NULL;
+       int             i;
+
+       if (ao_list_is_empty(&alarm_queue))
+               return;
+       ao_list_for_each_entry(alarm, &alarm_queue, struct ao_task, alarm_queue) {
+               if (prev) {
+                       if ((int16_t) (alarm->alarm - prev->alarm) < 0) {
+                               ao_panic(1);
+                       }
+               }
+               prev = alarm;
+       }
+       for (i = 0; i < ao_num_tasks; i++) {
+               alarm = ao_tasks[i];
+               if (alarm->alarm) {
+                       if (ao_list_is_empty(&alarm->alarm_queue))
+                               ao_panic(2);
+               } else {
+                       if (!ao_list_is_empty(&alarm->alarm_queue))
+                               ao_panic(3);
+               }
+       }
+}
+#else
+#define ao_task_validate_alarm_queue()
+#endif
+
+uint16_t       ao_task_alarm_tick;
+
+static void
+ao_task_to_alarm_queue(struct ao_task *task)
+{
+       struct ao_task  *alarm;
+       ao_list_for_each_entry(alarm, &alarm_queue, struct ao_task, alarm_queue) {
+               if ((int16_t) (alarm->alarm - task->alarm) >= 0) {
+                       ao_list_insert(&task->alarm_queue, alarm->alarm_queue.prev);
+                       ao_task_validate_alarm_queue();
+                       return;
+               }
+       }
+       ao_list_append(&task->alarm_queue, &alarm_queue);
+       ao_task_alarm_tick = ao_list_first_entry(&alarm_queue, struct ao_task, alarm_queue)->alarm;
+       ao_task_validate_alarm_queue();
+}
+
+static void
+ao_task_from_alarm_queue(struct ao_task *task)
+{
+       ao_list_del(&task->alarm_queue);
+       if (ao_list_is_empty(&alarm_queue))
+               ao_task_alarm_tick = 0;
+       else
+               ao_task_alarm_tick = ao_list_first_entry(&alarm_queue, struct ao_task, alarm_queue)->alarm;
+       ao_task_validate_alarm_queue();
+}
+
+static void
+ao_task_init_queue(struct ao_task *task)
+{
+       ao_list_init(&task->queue);
+       ao_list_init(&task->alarm_queue);
+}
+
+static void
+ao_task_exit_queue(struct ao_task *task)
+{
+       ao_list_del(&task->queue);
+       ao_list_del(&task->alarm_queue);
+}
+
+void
+ao_task_check_alarm(uint16_t tick)
+{
+       struct ao_task  *alarm, *next;
+
+       ao_list_for_each_entry_safe(alarm, next, &alarm_queue, struct ao_task, alarm_queue) {
+               if ((int16_t) (tick - alarm->alarm) < 0)
+                       break;
+               alarm->alarm = 0;
+               ao_task_from_alarm_queue(alarm);
+               ao_task_to_run_queue(alarm);
+       }
+}
+
+void
+ao_task_init(void)
+{
+       uint8_t i;
+       ao_list_init(&run_queue);
+       ao_list_init(&alarm_queue);
+       ao_task_alarm_tick = 0;
+       for (i = 0; i < SLEEP_HASH_SIZE; i++)
+               ao_list_init(&sleep_queue[i]);
+}
+
+#if DEBUG
+static uint8_t
+ao_task_validate_queue(struct ao_task *task)
+{
+       uint32_t flags;
+       struct ao_task *m;
+       uint8_t ret = 0;
+       struct ao_list *queue;
+
+       flags = ao_arch_irqsave();
+       if (task->wchan) {
+               queue = ao_task_sleep_queue(task->wchan);
+               ret |= 2;
+       } else {
+               queue = &run_queue;
+               ret |= 4;
+       }
+       ao_list_for_each_entry(m, queue, struct ao_task, queue) {
+               if (m == task) {
+                       ret |= 1;
+                       break;
+               }
+       }
+       ao_arch_irqrestore(flags);
+       return ret;
+}
+
+static uint8_t
+ao_task_validate_alarm(struct ao_task *task)
+{
+       uint32_t        flags;
+       struct ao_task  *m;
+       uint8_t         ret = 0;
+
+       flags = ao_arch_irqsave();
+       if (task->alarm == 0)
+               return 0xff;
+       ao_list_for_each_entry(m, &alarm_queue, struct ao_task, alarm_queue) {
+               if (m == task)
+                       ret |= 1;
+               else {
+                       if (!(ret&1)) {
+                               if ((int16_t) (m->alarm - task->alarm) > 0)
+                                       ret |= 2;
+                       } else {
+                               if ((int16_t) (task->alarm - m->alarm) > 0)
+                                       ret |= 4;
+                       }
+               }
+       }
+       ao_arch_irqrestore(flags);
+       return ret;
+}
+
+
+static void
+ao_task_validate(void)
+{
+       uint8_t         i;
+       struct ao_task  *task;
+       uint8_t         ret;
+
+       for (i = 0; i < ao_num_tasks; i++) {
+               task = ao_tasks[i];
+               ret = ao_task_validate_queue(task);
+               if (!(ret & 1)) {
+                       if (ret & 2)
+                               printf ("sleeping task not on sleep queue %s %08x\n",
+                                       task->name, task->wchan);
+                       else
+                               printf ("running task not on run queue %s\n",
+                                       task->name);
+               }
+               ret = ao_task_validate_alarm(task);
+               if (ret != 0xff) {
+                       if (!(ret & 1))
+                               printf ("alarm task not on alarm queue %s %d\n",
+                                       task->name, task->alarm);
+                       if (ret & 2)
+                               printf ("alarm queue has sooner entries after %s %d\n",
+                                       task->name, task->alarm);
+                       if (ret & 4)
+                               printf ("alarm queue has later entries before %s %d\n",
+                                       task->name, task->alarm);
+               }
+       }
+}
+#endif /* DEBUG */
+
+#endif /* HAS_TASK_QUEUE */
+
 void
 ao_add_task(__xdata struct ao_task * task, void (*start)(void), __code char *name) __reentrant
 {
@@ -42,7 +287,6 @@ ao_add_task(__xdata struct ao_task * task, void (*start)(void), __code char *nam
                if (t == ao_num_tasks)
                        break;
        }
-       ao_tasks[ao_num_tasks++] = task;
        task->task_id = task_id;
        task->name = name;
        task->wchan = NULL;
@@ -51,62 +295,125 @@ ao_add_task(__xdata struct ao_task * task, void (*start)(void), __code char *nam
         * to the start of the task
         */
        ao_arch_init_stack(task, start);
+       ao_arch_critical(
+#if HAS_TASK_QUEUE
+               ao_task_init_queue(task);
+               ao_task_to_run_queue(task);
+#endif
+               ao_tasks[ao_num_tasks] = task;
+               ao_num_tasks++;
+               );
 }
 
+__data uint8_t ao_task_minimize_latency;
+
 /* Task switching function. This must not use any stack variables */
 void
 ao_yield(void) ao_arch_naked_define
 {
        ao_arch_save_regs();
 
+#if HAS_TASK_QUEUE
+       if (ao_cur_task == NULL)
+               ao_cur_task = ao_tasks[ao_num_tasks-1];
+#else
        if (ao_cur_task_index == AO_NO_TASK_INDEX)
                ao_cur_task_index = ao_num_tasks-1;
+#endif
        else
        {
+#if HAS_SAMPLE_PROFILE
+               uint16_t        tick = ao_sample_profile_timer_value();
+               uint16_t        run = tick - ao_cur_task->start;
+               if (run > ao_cur_task->max_run)
+                       ao_cur_task->max_run = run;
+               ++ao_cur_task->yields;
+#endif
                ao_arch_save_stack();
        }
 
        ao_arch_isr_stack();
+#if !HAS_TASK_QUEUE
+       if (ao_task_minimize_latency)
+               ao_arch_release_interrupts();
+       else
+#endif
+               ao_arch_block_interrupts();
 
+#if AO_CHECK_STACK
+       in_yield = 1;
+#endif
        /* Find a task to run. If there isn't any runnable task,
         * this loop will run forever, which is just fine
         */
+#if HAS_TASK_QUEUE
+       /* If the current task is running, move it to the
+        * end of the queue to allow other tasks a chance
+        */
+       if (ao_cur_task->wchan == NULL)
+               ao_task_to_run_queue(ao_cur_task);
+       ao_cur_task = NULL;
+       for (;;) {
+               ao_arch_memory_barrier();
+               if (!ao_list_is_empty(&run_queue))
+                       break;
+               /* Wait for interrupts when there's nothing ready */
+               ao_arch_wait_interrupt();
+       }
+       ao_cur_task = ao_list_first_entry(&run_queue, struct ao_task, queue);
+#else
        {
-               __pdata uint8_t ao_next_task_index = ao_cur_task_index;
+               __pdata uint8_t ao_last_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_index;
+                       if (ao_cur_task_index == ao_num_tasks)
+                               ao_cur_task_index = 0;
+
+                       ao_cur_task = ao_tasks[ao_cur_task_index];
 
-                       ao_cur_task = ao_tasks[ao_next_task_index];
-                       if (ao_cur_task->wchan == NULL) {
-                               ao_cur_task_index = ao_next_task_index;
+                       /* Check for ready task */
+                       if (ao_cur_task->wchan == NULL)
                                break;
-                       }
 
                        /* Check if the alarm is set for a time which has passed */
                        if (ao_cur_task->alarm &&
-                           (int16_t) (ao_time() - ao_cur_task->alarm) >= 0) {
-                               ao_cur_task_index = ao_next_task_index;
+                           (int16_t) (ao_time() - ao_cur_task->alarm) >= 0)
                                break;
-                       }
 
-                       /* Enter lower power mode when there isn't anything to do */
-                       if (ao_next_task_index == ao_cur_task_index) {
-                               ao_arch_cpu_idle();
-                       }
+                       /* Wait for interrupts when there's nothing ready */
+                       if (ao_cur_task_index == ao_last_task_index && !ao_task_minimize_latency)
+                               ao_arch_wait_interrupt();
                }
        }
+#endif
+#if HAS_SAMPLE_PROFILE
+       ao_cur_task->start = ao_sample_profile_timer_value();
+#endif
+#if HAS_STACK_GUARD
+       ao_mpu_stack_guard(ao_cur_task->stack);
+#endif
+#if AO_CHECK_STACK
+       in_yield = 0;
+#endif
        ao_arch_restore_stack();
 }
 
 uint8_t
 ao_sleep(__xdata void *wchan)
 {
+#if HAS_TASK_QUEUE
+       uint32_t flags;
+       flags = ao_arch_irqsave();
+#endif
        ao_cur_task->wchan = wchan;
+#if HAS_TASK_QUEUE
+       ao_task_to_sleep_queue(ao_cur_task, wchan);
+       ao_arch_irqrestore(flags);
+#endif
        ao_yield();
        if (ao_cur_task->wchan) {
                ao_cur_task->wchan = NULL;
+               ao_cur_task->alarm = 0;
                return 1;
        }
        return 0;
@@ -115,47 +422,101 @@ ao_sleep(__xdata void *wchan)
 void
 ao_wakeup(__xdata void *wchan)
 {
-       uint8_t i;
+#if HAS_TASK_QUEUE
+       struct ao_task  *sleep, *next;
+       struct ao_list  *sleep_queue;
+       uint32_t        flags;
 
+       if (ao_num_tasks == 0)
+               return;
+       sleep_queue = ao_task_sleep_queue(wchan);
+       flags = ao_arch_irqsave();
+       ao_list_for_each_entry_safe(sleep, next, sleep_queue, struct ao_task, queue) {
+               if (sleep->wchan == wchan) {
+                       sleep->wchan = NULL;
+                       ao_task_to_run_queue(sleep);
+               }
+       }
+       ao_arch_irqrestore(flags);
+#else
+       uint8_t i;
        for (i = 0; i < ao_num_tasks; i++)
                if (ao_tasks[i]->wchan == wchan)
                        ao_tasks[i]->wchan = NULL;
+#endif
+       ao_check_stack();
 }
 
 void
 ao_alarm(uint16_t delay)
 {
+#if HAS_TASK_QUEUE
+       uint32_t flags;
        /* Make sure we sleep *at least* delay ticks, which means adding
         * one to account for the fact that we may be close to the next tick
         */
+       flags = ao_arch_irqsave();
+#endif
        if (!(ao_cur_task->alarm = ao_time() + delay + 1))
                ao_cur_task->alarm = 1;
+#if HAS_TASK_QUEUE
+       ao_task_to_alarm_queue(ao_cur_task);
+       ao_arch_irqrestore(flags);
+#endif
 }
 
 void
 ao_clear_alarm(void)
 {
+#if HAS_TASK_QUEUE
+       uint32_t flags;
+
+       flags = ao_arch_irqsave();
+#endif
        ao_cur_task->alarm = 0;
+#if HAS_TASK_QUEUE
+       ao_task_from_alarm_queue(ao_cur_task);
+       ao_arch_irqrestore(flags);
+#endif
+}
+
+static __xdata uint8_t ao_forever;
+
+void
+ao_delay(uint16_t ticks)
+{
+       ao_alarm(ticks);
+       ao_sleep(&ao_forever);
+       ao_clear_alarm();
 }
 
 void
 ao_exit(void)
 {
-       ao_arch_critical(
-               uint8_t i;
-               ao_num_tasks--;
-               for (i = ao_cur_task_index; i < ao_num_tasks; i++)
-                       ao_tasks[i] = ao_tasks[i+1];
-               ao_cur_task_index = AO_NO_TASK_INDEX;
-               ao_yield();
-               );
+       uint8_t i;
+       ao_arch_block_interrupts();
+       ao_num_tasks--;
+#if HAS_TASK_QUEUE
+       for (i = 0; i < ao_num_tasks; i++)
+               if (ao_tasks[i] == ao_cur_task)
+                       break;
+       ao_task_exit_queue(ao_cur_task);
+#else
+       i = ao_cur_task_index;
+       ao_cur_task_index = AO_NO_TASK_INDEX;
+#endif
+       for (; i < ao_num_tasks; i++)
+               ao_tasks[i] = ao_tasks[i+1];
+       ao_cur_task = NULL;
+       ao_yield();
        /* we'll never get back here */
 }
 
+#if HAS_TASK_INFO
 void
 ao_task_info(void)
 {
-       uint8_t i;
+       uint8_t         i;
        __xdata struct ao_task *task;
 
        for (i = 0; i < ao_num_tasks; i++) {
@@ -164,12 +525,21 @@ ao_task_info(void)
                       task->name,
                       (int) task->wchan);
        }
+#if HAS_TASK_QUEUE && DEBUG
+       ao_task_validate();
+#endif
 }
+#endif
 
 void
 ao_start_scheduler(void)
 {
+#if !HAS_TASK_QUEUE
        ao_cur_task_index = AO_NO_TASK_INDEX;
+#endif
        ao_cur_task = NULL;
+#if HAS_ARCH_START_SCHEDULER
+       ao_arch_start_scheduler();
+#endif
        ao_yield();
 }