xref: /btstack/platform/freertos/btstack_run_loop_freertos.c (revision a8d51f092f1b660d0f6921369ad2bc3f9368296c)
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 static bool run_loop_exit_requested;
109 
110 static uint32_t btstack_run_loop_freertos_get_time_ms(void){
111     return hal_time_ms();
112 }
113 
114 // set timer
115 static void btstack_run_loop_freertos_set_timer(btstack_timer_source_t *ts, uint32_t timeout_in_ms){
116     ts->timeout = btstack_run_loop_freertos_get_time_ms() + timeout_in_ms + 1;
117 }
118 
119 /**
120  * Add timer to run_loop (keep list sorted)
121  */
122 static void btstack_run_loop_freertos_add_timer(btstack_timer_source_t *ts){
123     btstack_linked_item_t *it;
124     for (it = (btstack_linked_item_t *) &timers; it->next ; it = it->next){
125         // don't add timer that's already in there
126         btstack_timer_source_t * next = (btstack_timer_source_t *) it->next;
127         if (next == ts){
128             log_error( "btstack_run_loop_timer_add error: timer to add already in list!");
129             return;
130         }
131         // exit if new timeout before list timeout
132         int32_t delta = btstack_time_delta(ts->timeout, next->timeout);
133         if (delta < 0) break;
134     }
135     ts->item.next = it->next;
136     it->next = (btstack_linked_item_t *) ts;
137 }
138 
139 /**
140  * Remove timer from run loop
141  */
142 static bool btstack_run_loop_freertos_remove_timer(btstack_timer_source_t *ts){
143     return btstack_linked_list_remove(&timers, (btstack_linked_item_t *) ts);
144 }
145 
146 static void btstack_run_loop_freertos_dump_timer(void){
147 #ifdef ENABLE_LOG_INFO
148     btstack_linked_item_t *it;
149     int i = 0;
150     for (it = (btstack_linked_item_t *) timers; it ; it = it->next){
151         btstack_timer_source_t *ts = (btstack_timer_source_t*) it;
152         log_info("timer %u, timeout %u\n", i, (unsigned int) ts->timeout);
153     }
154 #endif
155 }
156 
157 // schedules execution from regular thread
158 void btstack_run_loop_freertos_trigger(void){
159 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
160     xTaskNotify(btstack_run_loop_task, EVENT_GROUP_FLAG_RUN_LOOP, eSetBits);
161 #else
162     xEventGroupSetBits(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP);
163 #endif
164 }
165 
166 void btstack_run_loop_freertos_execute_code_on_main_thread(void (*fn)(void *arg), void * arg){
167 
168     // directly call function if already on btstack task
169     if (xTaskGetCurrentTaskHandle() == btstack_run_loop_task){
170         (*fn)(arg);
171         return;
172     }
173 
174     function_call_t message;
175     message.fn  = fn;
176     message.arg = arg;
177     BaseType_t res = xQueueSendToBack(btstack_run_loop_queue, &message, 0); // portMAX_DELAY);
178     if (res != pdTRUE){
179         log_error("Failed to post fn %p", fn);
180     }
181     btstack_run_loop_freertos_trigger();
182 }
183 
184 #if defined(HAVE_FREERTOS_TASK_NOTIFICATIONS) || (INCLUDE_xEventGroupSetBitFromISR == 1)
185 void btstack_run_loop_freertos_trigger_from_isr(void){
186     BaseType_t xHigherPriorityTaskWoken;
187 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
188     xTaskNotifyFromISR(btstack_run_loop_task, EVENT_GROUP_FLAG_RUN_LOOP, eSetBits, &xHigherPriorityTaskWoken);
189     if (xHigherPriorityTaskWoken) {
190 #ifdef ESP_PLATFORM
191         portYIELD_FROM_ISR();
192 #else
193         portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
194 #endif
195     }
196 #else
197     xEventGroupSetBitsFromISR(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP, &xHigherPriorityTaskWoken);
198 #endif
199 }
200 
201 void btstack_run_loop_freertos_execute_code_on_main_thread_from_isr(void (*fn)(void *arg), void * arg){
202     function_call_t message;
203     message.fn  = fn;
204     message.arg = arg;
205     BaseType_t xHigherPriorityTaskWoken;
206     xQueueSendToBackFromISR(btstack_run_loop_queue, &message, &xHigherPriorityTaskWoken);
207     btstack_run_loop_freertos_trigger_from_isr();
208 }
209 #endif
210 
211 void btstack_run_loop_freertos_trigger_exit(void){
212     run_loop_exit_requested = true;
213 }
214 
215 /**
216  * Execute run_loop
217  */
218 static void btstack_run_loop_freertos_execute(void) {
219     log_debug("RL: execute");
220 
221     run_loop_exit_requested = false;
222 
223     while (true) {
224 
225         // process data sources
226         btstack_data_source_t *ds;
227         btstack_data_source_t *next;
228         for (ds = (btstack_data_source_t *) data_sources; ds != NULL ; ds = next){
229             next = (btstack_data_source_t *) ds->item.next; // cache pointer to next data_source to allow data source to remove itself
230             if (ds->flags & DATA_SOURCE_CALLBACK_POLL){
231                 ds->process(ds, DATA_SOURCE_CALLBACK_POLL);
232             }
233         }
234 
235         // process registered function calls on run loop thread
236         while (true){
237             function_call_t message = { NULL, NULL };
238             BaseType_t res = xQueueReceive( btstack_run_loop_queue, &message, 0);
239             if (res == pdFALSE) break;
240             if (message.fn){
241                 message.fn(message.arg);
242             }
243         }
244 
245         // process timers and get next timeout
246         uint32_t timeout_ms = portMAX_DELAY;
247         log_debug("RL: portMAX_DELAY %u", portMAX_DELAY);
248         while (timers) {
249             btstack_timer_source_t * ts = (btstack_timer_source_t *) timers;
250             uint32_t now = btstack_run_loop_freertos_get_time_ms();
251             int32_t delta_ms = btstack_time_delta(ts->timeout, now);
252             log_debug("RL: now %u, expires %u -> delta %d", now, ts->timeout, delta_ms);
253             if (delta_ms > 0){
254                 timeout_ms = delta_ms;
255                 break;
256             }
257             // remove timer before processing it to allow handler to re-register with run loop
258             btstack_run_loop_freertos_remove_timer(ts);
259             log_debug("RL: first timer %p", ts->process);
260             ts->process(ts);
261         }
262 
263         // exit triggered by btstack_run_loop_freertos_trigger_exit (from data source, timer, run on main thread)
264         if (run_loop_exit_requested) break;
265 
266         // wait for timeout or event group/task notification
267         log_debug("RL: wait with timeout %u", (int) timeout_ms);
268 #ifdef HAVE_FREERTOS_TASK_NOTIFICATIONS
269         xTaskNotifyWait(pdFALSE, 0xffffffff, NULL, pdMS_TO_TICKS(timeout_ms));
270 #else
271         xEventGroupWaitBits(btstack_run_loop_event_group, EVENT_GROUP_FLAG_RUN_LOOP, 1, 0, pdMS_TO_TICKS(timeout_ms));
272 #endif
273     }
274 }
275 
276 static void btstack_run_loop_freertos_add_data_source(btstack_data_source_t *ds){
277     btstack_linked_list_add(&data_sources, (btstack_linked_item_t *) ds);
278 }
279 
280 static bool btstack_run_loop_freertos_remove_data_source(btstack_data_source_t *ds){
281     return btstack_linked_list_remove(&data_sources, (btstack_linked_item_t *) ds);
282 }
283 
284 static void btstack_run_loop_freertos_enable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){
285     ds->flags |= callback_types;
286 }
287 
288 static void btstack_run_loop_freertos_disable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){
289     ds->flags &= ~callback_types;
290 }
291 
292 static void btstack_run_loop_freertos_init(void){
293     timers = NULL;
294 
295 #ifdef USE_STATIC_ALLOC
296     btstack_run_loop_queue = xQueueCreateStatic(RUN_LOOP_QUEUE_LENGTH, RUN_LOOP_QUEUE_ITEM_SIZE, btstack_run_loop_queue_storage, &btstack_run_loop_queue_object);
297 #else
298     btstack_run_loop_queue = xQueueCreate(RUN_LOOP_QUEUE_LENGTH, RUN_LOOP_QUEUE_ITEM_SIZE);
299 #endif
300 
301 #ifndef HAVE_FREERTOS_TASK_NOTIFICATIONS
302     // event group to wake run loop
303     btstack_run_loop_event_group = xEventGroupCreate();
304 #endif
305 
306     // task to handle to optimize 'run on main thread'
307     btstack_run_loop_task = xTaskGetCurrentTaskHandle();
308 
309     log_info("run loop init, task %p, queue item size %u", btstack_run_loop_task, (int) sizeof(function_call_t));
310 }
311 
312 /**
313  * @brief Provide btstack_run_loop_posix instance for use with btstack_run_loop_init
314  */
315 
316 static const btstack_run_loop_t btstack_run_loop_freertos = {
317     &btstack_run_loop_freertos_init,
318     &btstack_run_loop_freertos_add_data_source,
319     &btstack_run_loop_freertos_remove_data_source,
320     &btstack_run_loop_freertos_enable_data_source_callbacks,
321     &btstack_run_loop_freertos_disable_data_source_callbacks,
322     &btstack_run_loop_freertos_set_timer,
323     &btstack_run_loop_freertos_add_timer,
324     &btstack_run_loop_freertos_remove_timer,
325     &btstack_run_loop_freertos_execute,
326     &btstack_run_loop_freertos_dump_timer,
327     &btstack_run_loop_freertos_get_time_ms,
328 };
329 
330 const btstack_run_loop_t * btstack_run_loop_freertos_get_instance(void){
331     return &btstack_run_loop_freertos;
332 }
333