xref: /btstack/platform/freertos/btstack_run_loop_freertos.c (revision 7cdc89a533ca236b2c2564b759993b788bae89d3)
1 /*
2  * Copyright (C) 2017 BlueKitchen GmbH
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the copyright holders nor the names of
14  *    contributors may be used to endorse or promote products derived
15  *    from this software without specific prior written permission.
16  * 4. Any redistribution, use, or modification is done solely for
17  *    personal benefit and not for any commercial purpose or for
18  *    monetary gain.
19  *
20  * THIS SOFTWARE IS PROVIDED BY BLUEKITCHEN GMBH AND CONTRIBUTORS
21  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL MATTHIAS
24  * RINGWALD OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
30  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  * Please inquire about commercial licensing options at
34  * [email protected]
35  *
36  */
37 
38 /*
39  *  btstack_run_loop_freertos.c
40  *
41  *  Run loop on dedicated thread on FreeRTOS
42  *  The run loop is triggered from other task/ISRs either via Event Groups
43  *  or Task Notifications if HAVE_FREERTOS_TASK_NOTIFICATIONS is defined
44  */
45 
46 #define BTSTACK_FILE__ "btstack_run_loop_freertos.c"
47 
48 #include <stddef.h> // NULL
49 
50 #include "btstack_run_loop_freertos.h"
51 
52 #include "btstack_linked_list.h"
53 #include "btstack_debug.h"
54 #include "btstack_util.h"
55 #include "hal_time_ms.h"
56 
57 // some SDKs, e.g. esp-idf, place FreeRTOS headers into an 'freertos' folder to avoid name collisions (e.g. list.h, queue.h, ..)
58 // wih this flag, the headers are properly found
59 
60 #ifdef HAVE_FREERTOS_INCLUDE_PREFIX
61 #include "freertos/FreeRTOS.h"
62 #include "freertos/task.h"
63 #include "freertos/queue.h"
64 #include "freertos/event_groups.h"
65 #else
66 #include "FreeRTOS.h"
67 #include "task.h"
68 #include "queue.h"
69 #include "event_groups.h"
70 #endif
71 
72 typedef struct function_call {
73     void (*fn)(void * arg);
74     void * arg;
75 } function_call_t;
76 
77 // pick allocation style, prefer static
78 #if( configSUPPORT_STATIC_ALLOCATION == 1 )
79 #define USE_STATIC_ALLOC
80 #elif( configSUPPORT_DYNAMIC_ALLOCATION == 1 )
81 // ok, nothing to do
82 #else
83 #error "Either configSUPPORT_STATIC_ALLOCATION or configSUPPORT_DYNAMIC_ALLOCATION in FreeRTOSConfig.h must be 1"
84 #endif
85 
86 // queue to receive events: up to 2 calls from transport, rest for app
87 #define RUN_LOOP_QUEUE_LENGTH 20
88 #define RUN_LOOP_QUEUE_ITEM_SIZE sizeof(function_call_t)
89 
90 #ifdef USE_STATIC_ALLOC
91 static StaticQueue_t btstack_run_loop_queue_object;
92 static uint8_t btstack_run_loop_queue_storage[ RUN_LOOP_QUEUE_LENGTH * RUN_LOOP_QUEUE_ITEM_SIZE ];
93 #endif
94 
95 static QueueHandle_t        btstack_run_loop_queue;
96 static TaskHandle_t         btstack_run_loop_task;
97 
98 #ifndef HAVE_FREERTOS_TASK_NOTIFICATIONS
99 static EventGroupHandle_t   btstack_run_loop_event_group;
100 #endif
101 
102 // bit 0 event group reserved to wakeup run loop
103 #define EVENT_GROUP_FLAG_RUN_LOOP 1
104 
105 // the run loop
106 static btstack_linked_list_t timers;
107 static btstack_linked_list_t data_sources;
108 
109 static uint32_t btstack_run_loop_freertos_get_time_ms(void){
110     return hal_time_ms();
111 }
112 
113 // set timer
114 static void btstack_run_loop_freertos_set_timer(btstack_timer_source_t *ts, uint32_t timeout_in_ms){
115     ts->timeout = btstack_run_loop_freertos_get_time_ms() + timeout_in_ms + 1;
116 }
117 
118 /**
119  * Add timer to run_loop (keep list sorted)
120  */
121 static void btstack_run_loop_freertos_add_timer(btstack_timer_source_t *ts){
122     btstack_linked_item_t *it;
123     for (it = (btstack_linked_item_t *) &timers; it->next ; it = it->next){
124         // don't add timer that's already in there
125         btstack_timer_source_t * next = (btstack_timer_source_t *) it->next;
126         if (next == ts){
127             log_error( "btstack_run_loop_timer_add error: timer to add already in list!");
128             return;
129         }
130         // exit if new timeout before list timeout
131         int32_t delta = btstack_time_delta(ts->timeout, next->timeout);
132         if (delta < 0) break;
133     }
134     ts->item.next = it->next;
135     it->next = (btstack_linked_item_t *) ts;
136 }
137 
138 /**
139  * Remove timer from run loop
140  */
141 static bool btstack_run_loop_freertos_remove_timer(btstack_timer_source_t *ts){
142     return btstack_linked_list_remove(&timers, (btstack_linked_item_t *) ts);
143 }
144 
145 static void btstack_run_loop_freertos_dump_timer(void){
146 #ifdef ENABLE_LOG_INFO
147     btstack_linked_item_t *it;
148     int i = 0;
149     for (it = (btstack_linked_item_t *) timers; it ; it = it->next){
150         btstack_timer_source_t *ts = (btstack_timer_source_t*) it;
151         log_info("timer %u, timeout %u\n", i, (unsigned int) ts->timeout);
152     }
153 #endif
154 }
155 
156 // schedules execution from regular thread
157 void btstack_run_loop_freertos_trigger(void){
158 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
159     xTaskNotify(btstack_run_loop_task, EVENT_GROUP_FLAG_RUN_LOOP, eSetBits);
160 #else
161     xEventGroupSetBits(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP);
162 #endif
163 }
164 
165 void btstack_run_loop_freertos_execute_code_on_main_thread(void (*fn)(void *arg), void * arg){
166 
167     // directly call function if already on btstack task
168     if (xTaskGetCurrentTaskHandle() == btstack_run_loop_task){
169         (*fn)(arg);
170         return;
171     }
172 
173     function_call_t message;
174     message.fn  = fn;
175     message.arg = arg;
176     BaseType_t res = xQueueSendToBack(btstack_run_loop_queue, &message, 0); // portMAX_DELAY);
177     if (res != pdTRUE){
178         log_error("Failed to post fn %p", fn);
179     }
180     btstack_run_loop_freertos_trigger();
181 }
182 
183 #if defined(HAVE_FREERTOS_TASK_NOTIFICATIONS) || (INCLUDE_xEventGroupSetBitFromISR == 1)
184 void btstack_run_loop_freertos_trigger_from_isr(void){
185     BaseType_t xHigherPriorityTaskWoken;
186 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
187     xTaskNotifyFromISR(btstack_run_loop_task, EVENT_GROUP_FLAG_RUN_LOOP, eSetBits, &xHigherPriorityTaskWoken);
188     if (xHigherPriorityTaskWoken) {
189 #ifdef ESP_PLATFORM
190         portYIELD_FROM_ISR();
191 #else
192         portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
193 #endif
194     }
195 #else
196     xEventGroupSetBitsFromISR(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP, &xHigherPriorityTaskWoken);
197 #endif
198 }
199 
200 void btstack_run_loop_freertos_execute_code_on_main_thread_from_isr(void (*fn)(void *arg), void * arg){
201     function_call_t message;
202     message.fn  = fn;
203     message.arg = arg;
204     BaseType_t xHigherPriorityTaskWoken;
205     xQueueSendToBackFromISR(btstack_run_loop_queue, &message, &xHigherPriorityTaskWoken);
206     btstack_run_loop_freertos_trigger_from_isr();
207 }
208 #endif
209 
210 /**
211  * Execute run_loop
212  */
213 static void btstack_run_loop_freertos_execute(void) {
214     log_debug("RL: execute");
215 
216     while (true) {
217 
218         // process data sources
219         btstack_data_source_t *ds;
220         btstack_data_source_t *next;
221         for (ds = (btstack_data_source_t *) data_sources; ds != NULL ; ds = next){
222             next = (btstack_data_source_t *) ds->item.next; // cache pointer to next data_source to allow data source to remove itself
223             if (ds->flags & DATA_SOURCE_CALLBACK_POLL){
224                 ds->process(ds, DATA_SOURCE_CALLBACK_POLL);
225             }
226         }
227 
228         // process registered function calls on run loop thread
229         while (true){
230             function_call_t message = { NULL, NULL };
231             BaseType_t res = xQueueReceive( btstack_run_loop_queue, &message, 0);
232             if (res == pdFALSE) break;
233             if (message.fn){
234                 message.fn(message.arg);
235             }
236         }
237 
238         // process timers and get next timeout
239         uint32_t timeout_ms = portMAX_DELAY;
240         log_debug("RL: portMAX_DELAY %u", portMAX_DELAY);
241         while (timers) {
242             btstack_timer_source_t * ts = (btstack_timer_source_t *) timers;
243             uint32_t now = btstack_run_loop_freertos_get_time_ms();
244             int32_t delta_ms = btstack_time_delta(ts->timeout, now);
245             log_debug("RL: now %u, expires %u -> delta %d", now, ts->timeout, delta_ms);
246             if (delta_ms > 0){
247                 timeout_ms = delta_ms;
248                 break;
249             }
250             // remove timer before processing it to allow handler to re-register with run loop
251             btstack_run_loop_freertos_remove_timer(ts);
252             log_debug("RL: first timer %p", ts->process);
253             ts->process(ts);
254         }
255 
256         // wait for timeout or event group/task notification
257         log_debug("RL: wait with timeout %u", (int) timeout_ms);
258 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
259         xTaskNotifyWait(pdFALSE, 0xffffffff, NULL, pdMS_TO_TICKS(timeout_ms));
260 #else
261         xEventGroupWaitBits(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP, 1, 0, pdMS_TO_TICKS(timeout_ms));
262 #endif
263     }
264 }
265 
266 static void btstack_run_loop_freertos_add_data_source(btstack_data_source_t *ds){
267     btstack_linked_list_add(&data_sources, (btstack_linked_item_t *) ds);
268 }
269 
270 static bool btstack_run_loop_freertos_remove_data_source(btstack_data_source_t *ds){
271     return btstack_linked_list_remove(&data_sources, (btstack_linked_item_t *) ds);
272 }
273 
274 static void btstack_run_loop_freertos_enable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){
275     ds->flags |= callback_types;
276 }
277 
278 static void btstack_run_loop_freertos_disable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){
279     ds->flags &= ~callback_types;
280 }
281 
282 static void btstack_run_loop_freertos_init(void){
283     timers = NULL;
284 
285 #ifdef USE_STATIC_ALLOC
286     btstack_run_loop_queue = xQueueCreateStatic(RUN_LOOP_QUEUE_LENGTH, RUN_LOOP_QUEUE_ITEM_SIZE, btstack_run_loop_queue_storage, &btstack_run_loop_queue_object);
287 #else
288     btstack_run_loop_queue = xQueueCreate(RUN_LOOP_QUEUE_LENGTH, RUN_LOOP_QUEUE_ITEM_SIZE);
289 #endif
290 
291 #ifndef HAVE_FREERTOS_TASK_NOTIFICATIONS
292     // event group to wake run loop
293     btstack_run_loop_event_group = xEventGroupCreate();
294 #endif
295 
296     // task to handle to optimize 'run on main thread'
297     btstack_run_loop_task = xTaskGetCurrentTaskHandle();
298 
299     log_info("run loop init, task %p, queue item size %u", btstack_run_loop_task, (int) sizeof(function_call_t));
300 }
301 
302 /**
303  * @brief Provide btstack_run_loop_posix instance for use with btstack_run_loop_init
304  */
305 
306 static const btstack_run_loop_t btstack_run_loop_freertos = {
307     &btstack_run_loop_freertos_init,
308     &btstack_run_loop_freertos_add_data_source,
309     &btstack_run_loop_freertos_remove_data_source,
310     &btstack_run_loop_freertos_enable_data_source_callbacks,
311     &btstack_run_loop_freertos_disable_data_source_callbacks,
312     &btstack_run_loop_freertos_set_timer,
313     &btstack_run_loop_freertos_add_timer,
314     &btstack_run_loop_freertos_remove_timer,
315     &btstack_run_loop_freertos_execute,
316     &btstack_run_loop_freertos_dump_timer,
317     &btstack_run_loop_freertos_get_time_ms,
318 };
319 
320 const btstack_run_loop_t * btstack_run_loop_freertos_get_instance(void){
321     return &btstack_run_loop_freertos;
322 }
323