1 /* 2 * Copyright (C) 2014 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_embedded.c 40 * 41 * For this run loop, we assume that there's no global way to wait for a list 42 * of data sources to get ready. Instead, each data source has to queried 43 * individually. Calling ds->isReady() before calling ds->process() doesn't 44 * make sense, so we just poll each data source round robin. 45 * 46 * To support an idle state, where an MCU could go to sleep, the process function 47 * has to return if it has to called again as soon as possible 48 * 49 * After calling process() on every data source and evaluating the pending timers, 50 * the idle hook gets called if no data source did indicate that it needs to be 51 * called right away. 52 * 53 */ 54 55 56 #include "btstack_run_loop.h" 57 #include "btstack_run_loop_embedded.h" 58 #include "btstack_linked_list.h" 59 #include "hal_tick.h" 60 #include "hal_cpu.h" 61 62 #include "btstack_debug.h" 63 64 #include <stddef.h> // NULL 65 66 #ifdef HAVE_EMBEDDED_TIME_MS 67 #include "hal_time_ms.h" 68 #endif 69 70 #if defined(HAVE_EMBEDDED_TICK) && defined(HAVE_EMBEDDED_TIME_MS) 71 #error "Please specify either HAVE_EMBEDDED_TICK or HAVE_EMBEDDED_TIME_MS" 72 #endif 73 74 #if defined(HAVE_EMBEDDED_TICK) || defined(HAVE_EMBEDDED_TIME_MS) 75 #define TIMER_SUPPORT 76 #endif 77 78 static const btstack_run_loop_t btstack_run_loop_embedded; 79 80 // the run loop 81 static btstack_linked_list_t data_sources; 82 83 #ifdef TIMER_SUPPORT 84 static btstack_linked_list_t timers; 85 #endif 86 87 #ifdef HAVE_EMBEDDED_TICK 88 static volatile uint32_t system_ticks; 89 #endif 90 91 static int trigger_event_received = 0; 92 93 /** 94 * Add data_source to run_loop 95 */ 96 static void btstack_run_loop_embedded_add_data_source(btstack_data_source_t *ds){ 97 btstack_linked_list_add(&data_sources, (btstack_linked_item_t *) ds); 98 } 99 100 /** 101 * Remove data_source from run loop 102 */ 103 static int btstack_run_loop_embedded_remove_data_source(btstack_data_source_t *ds){ 104 return btstack_linked_list_remove(&data_sources, (btstack_linked_item_t *) ds); 105 } 106 107 // set timer 108 static void btstack_run_loop_embedded_set_timer(btstack_timer_source_t *ts, uint32_t timeout_in_ms){ 109 #ifdef HAVE_EMBEDDED_TICK 110 uint32_t ticks = btstack_run_loop_embedded_ticks_for_ms(timeout_in_ms); 111 if (ticks == 0) ticks++; 112 // time until next tick is < hal_tick_get_tick_period_in_ms() and we don't know, so we add one 113 ts->timeout = system_ticks + 1 + ticks; 114 #endif 115 #ifdef HAVE_EMBEDDED_TIME_MS 116 ts->timeout = hal_time_ms() + timeout_in_ms + 1; 117 #endif 118 } 119 120 // under the assumption that a tick value is +/- 2^30 away from now, calculate the upper bits of the tick value 121 static int btstack_run_loop_embedded_reconstruct_higher_bits(uint32_t now, uint32_t ticks){ 122 int32_t delta = ticks - now; 123 if (delta >= 0){ 124 if (ticks >= now) { 125 return 0; 126 } else { 127 return 1; 128 } 129 } else { 130 if (ticks < now) { 131 return 0; 132 } else { 133 return -1; 134 } 135 } 136 } 137 138 /** 139 * Add timer to run_loop (keep list sorted) 140 */ 141 static void btstack_run_loop_embedded_add_timer(btstack_timer_source_t *ts){ 142 #ifdef TIMER_SUPPORT 143 144 #ifdef HAVE_EMBEDDED_TICK 145 uint32_t now = system_ticks; 146 #endif 147 #ifdef HAVE_EMBEDDED_TIME_MS 148 uint32_t now = hal_time_ms(); 149 #endif 150 151 uint32_t new_low = ts->timeout; 152 int new_high = btstack_run_loop_embedded_reconstruct_higher_bits(now, new_low); 153 154 btstack_linked_item_t *it; 155 for (it = (btstack_linked_item_t *) &timers; it->next ; it = it->next){ 156 // don't add timer that's already in there 157 if ((btstack_timer_source_t *) it->next == ts){ 158 log_error( "btstack_run_loop_timer_add error: timer to add already in list!"); 159 return; 160 } 161 uint32_t next_low = ((btstack_timer_source_t *) it->next)->timeout; 162 int next_high = btstack_run_loop_embedded_reconstruct_higher_bits(now, next_low); 163 if (new_high < next_high || ((new_high == next_high) && (new_low < next_low))){ 164 break; 165 } 166 } 167 ts->item.next = it->next; 168 it->next = (btstack_linked_item_t *) ts; 169 #endif 170 } 171 172 /** 173 * Remove timer from run loop 174 */ 175 static int btstack_run_loop_embedded_remove_timer(btstack_timer_source_t *ts){ 176 #ifdef TIMER_SUPPORT 177 return btstack_linked_list_remove(&timers, (btstack_linked_item_t *) ts); 178 #else 179 return 0; 180 #endif 181 } 182 183 static void btstack_run_loop_embedded_dump_timer(void){ 184 #ifdef TIMER_SUPPORT 185 #ifdef ENABLE_LOG_INFO 186 btstack_linked_item_t *it; 187 int i = 0; 188 for (it = (btstack_linked_item_t *) timers; it ; it = it->next){ 189 btstack_timer_source_t *ts = (btstack_timer_source_t*) it; 190 log_info("timer %u, timeout %u\n", i, (unsigned int) ts->timeout); 191 } 192 #endif 193 #endif 194 } 195 196 static void btstack_run_loop_embedded_enable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){ 197 ds->flags |= callback_types; 198 } 199 200 static void btstack_run_loop_embedded_disable_data_source_callbacks(btstack_data_source_t * ds, uint16_t callback_types){ 201 ds->flags &= ~callback_types; 202 } 203 204 /** 205 * Execute run_loop once 206 */ 207 void btstack_run_loop_embedded_execute_once(void) { 208 btstack_data_source_t *ds; 209 210 // process data sources 211 btstack_data_source_t *next; 212 for (ds = (btstack_data_source_t *) data_sources; ds != NULL ; ds = next){ 213 next = (btstack_data_source_t *) ds->item.next; // cache pointer to next data_source to allow data source to remove itself 214 if (ds->flags & DATA_SOURCE_CALLBACK_POLL){ 215 ds->process(ds, DATA_SOURCE_CALLBACK_POLL); 216 } 217 } 218 219 #ifdef TIMER_SUPPORT 220 221 #ifdef HAVE_EMBEDDED_TICK 222 uint32_t now = system_ticks; 223 #endif 224 #ifdef HAVE_EMBEDDED_TIME_MS 225 uint32_t now = hal_time_ms(); 226 #endif 227 228 // process timers 229 while (timers) { 230 btstack_timer_source_t *ts = (btstack_timer_source_t *) timers; 231 uint32_t timeout_low = ts->timeout; 232 int timeout_high = btstack_run_loop_embedded_reconstruct_higher_bits(now, timeout_low); 233 if (timeout_high > 0 || ((timeout_high == 0) && (timeout_low > now))) break; 234 btstack_run_loop_remove_timer(ts); 235 ts->process(ts); 236 } 237 #endif 238 239 // disable IRQs and check if run loop iteration has been requested. if not, go to sleep 240 hal_cpu_disable_irqs(); 241 if (trigger_event_received){ 242 trigger_event_received = 0; 243 hal_cpu_enable_irqs(); 244 } else { 245 hal_cpu_enable_irqs_and_sleep(); 246 } 247 } 248 249 /** 250 * Execute run_loop 251 */ 252 static void btstack_run_loop_embedded_execute(void) { 253 while (1) { 254 btstack_run_loop_embedded_execute_once(); 255 } 256 } 257 258 #ifdef HAVE_EMBEDDED_TICK 259 static void btstack_run_loop_embedded_tick_handler(void){ 260 system_ticks++; 261 trigger_event_received = 1; 262 } 263 264 uint32_t btstack_run_loop_embedded_get_ticks(void){ 265 return system_ticks; 266 } 267 268 uint32_t btstack_run_loop_embedded_ticks_for_ms(uint32_t time_in_ms){ 269 return time_in_ms / hal_tick_get_tick_period_in_ms(); 270 } 271 #endif 272 273 static uint32_t btstack_run_loop_embedded_get_time_ms(void){ 274 #ifdef HAVE_EMBEDDED_TIME_MS 275 return hal_time_ms(); 276 #endif 277 #ifdef HAVE_EMBEDDED_TICK 278 return system_ticks * hal_tick_get_tick_period_in_ms(); 279 #endif 280 return 0; 281 } 282 283 284 /** 285 * trigger run loop iteration 286 */ 287 void btstack_run_loop_embedded_trigger(void){ 288 trigger_event_received = 1; 289 } 290 291 static void btstack_run_loop_embedded_init(void){ 292 data_sources = NULL; 293 294 #ifdef TIMER_SUPPORT 295 timers = NULL; 296 #endif 297 298 #ifdef HAVE_EMBEDDED_TICK 299 system_ticks = 0; 300 hal_tick_init(); 301 hal_tick_set_handler(&btstack_run_loop_embedded_tick_handler); 302 #endif 303 } 304 305 /** 306 * Provide btstack_run_loop_embedded instance 307 */ 308 const btstack_run_loop_t * btstack_run_loop_embedded_get_instance(void){ 309 return &btstack_run_loop_embedded; 310 } 311 312 static const btstack_run_loop_t btstack_run_loop_embedded = { 313 &btstack_run_loop_embedded_init, 314 &btstack_run_loop_embedded_add_data_source, 315 &btstack_run_loop_embedded_remove_data_source, 316 &btstack_run_loop_embedded_enable_data_source_callbacks, 317 &btstack_run_loop_embedded_disable_data_source_callbacks, 318 &btstack_run_loop_embedded_set_timer, 319 &btstack_run_loop_embedded_add_timer, 320 &btstack_run_loop_embedded_remove_timer, 321 &btstack_run_loop_embedded_execute, 322 &btstack_run_loop_embedded_dump_timer, 323 &btstack_run_loop_embedded_get_time_ms, 324 }; 325