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hal/LowPowerTickerWrapper.cpp@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
188:bcfe06ba3d64 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
AnnaBridge 188:bcfe06ba3d64 1 /* mbed Microcontroller Library
AnnaBridge 188:bcfe06ba3d64 2 * Copyright (c) 2018 ARM Limited
AnnaBridge 189:f392fc9709a3 3 * SPDX-License-Identifier: Apache-2.0
AnnaBridge 188:bcfe06ba3d64 4 *
AnnaBridge 188:bcfe06ba3d64 5 * Licensed under the Apache License, Version 2.0 (the "License");
AnnaBridge 188:bcfe06ba3d64 6 * you may not use this file except in compliance with the License.
AnnaBridge 188:bcfe06ba3d64 7 * You may obtain a copy of the License at
AnnaBridge 188:bcfe06ba3d64 8 *
AnnaBridge 188:bcfe06ba3d64 9 * http://www.apache.org/licenses/LICENSE-2.0
AnnaBridge 188:bcfe06ba3d64 10 *
AnnaBridge 188:bcfe06ba3d64 11 * Unless required by applicable law or agreed to in writing, software
AnnaBridge 188:bcfe06ba3d64 12 * distributed under the License is distributed on an "AS IS" BASIS,
AnnaBridge 188:bcfe06ba3d64 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
AnnaBridge 188:bcfe06ba3d64 14 * See the License for the specific language governing permissions and
AnnaBridge 188:bcfe06ba3d64 15 * limitations under the License.
AnnaBridge 188:bcfe06ba3d64 16 */
AnnaBridge 188:bcfe06ba3d64 17 #include "hal/LowPowerTickerWrapper.h"
AnnaBridge 188:bcfe06ba3d64 18 #include "platform/Callback.h"
AnnaBridge 188:bcfe06ba3d64 19
AnnaBridge 188:bcfe06ba3d64 20 LowPowerTickerWrapper::LowPowerTickerWrapper(const ticker_data_t *data, const ticker_interface_t *interface, uint32_t min_cycles_between_writes, uint32_t min_cycles_until_match)
AnnaBridge 188:bcfe06ba3d64 21 : _intf(data->interface), _min_count_between_writes(min_cycles_between_writes + 1), _min_count_until_match(min_cycles_until_match + 1), _suspended(false)
AnnaBridge 188:bcfe06ba3d64 22 {
AnnaBridge 188:bcfe06ba3d64 23 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 24
AnnaBridge 188:bcfe06ba3d64 25 this->data.interface = interface;
AnnaBridge 188:bcfe06ba3d64 26 this->data.queue = data->queue;
AnnaBridge 188:bcfe06ba3d64 27 _reset();
AnnaBridge 188:bcfe06ba3d64 28
AnnaBridge 188:bcfe06ba3d64 29 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 30 }
AnnaBridge 188:bcfe06ba3d64 31
AnnaBridge 188:bcfe06ba3d64 32 void LowPowerTickerWrapper::irq_handler(ticker_irq_handler_type handler)
AnnaBridge 188:bcfe06ba3d64 33 {
AnnaBridge 188:bcfe06ba3d64 34 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 35
AnnaBridge 189:f392fc9709a3 36 // This code no longer filters out early interrupts. Instead it
AnnaBridge 189:f392fc9709a3 37 // passes them through to the next layer and ignores further interrupts
AnnaBridge 189:f392fc9709a3 38 // until the next call to set_interrrupt or fire_interrupt (when not suspended).
AnnaBridge 189:f392fc9709a3 39 // This is to ensure that the device doesn't get stuck in sleep due to an
AnnaBridge 189:f392fc9709a3 40 // early low power ticker interrupt that was ignored.
AnnaBridge 189:f392fc9709a3 41 if (_pending_fire_now || _pending_match || _suspended) {
AnnaBridge 188:bcfe06ba3d64 42 _timeout.detach();
AnnaBridge 188:bcfe06ba3d64 43 _pending_timeout = false;
AnnaBridge 188:bcfe06ba3d64 44 _pending_match = false;
AnnaBridge 188:bcfe06ba3d64 45 _pending_fire_now = false;
AnnaBridge 188:bcfe06ba3d64 46 if (handler) {
AnnaBridge 188:bcfe06ba3d64 47 handler(&data);
AnnaBridge 188:bcfe06ba3d64 48 }
AnnaBridge 188:bcfe06ba3d64 49 } else {
AnnaBridge 188:bcfe06ba3d64 50 // Spurious interrupt
AnnaBridge 188:bcfe06ba3d64 51 _intf->clear_interrupt();
AnnaBridge 188:bcfe06ba3d64 52 }
AnnaBridge 188:bcfe06ba3d64 53
AnnaBridge 188:bcfe06ba3d64 54 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 55 }
AnnaBridge 188:bcfe06ba3d64 56
AnnaBridge 188:bcfe06ba3d64 57 void LowPowerTickerWrapper::suspend()
AnnaBridge 188:bcfe06ba3d64 58 {
AnnaBridge 188:bcfe06ba3d64 59 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 60
AnnaBridge 188:bcfe06ba3d64 61 // Wait until rescheduling is allowed
AnnaBridge 188:bcfe06ba3d64 62 while (!_set_interrupt_allowed) {
AnnaBridge 188:bcfe06ba3d64 63 timestamp_t current = _intf->read();
AnnaBridge 188:bcfe06ba3d64 64 if (((current - _last_actual_set_interrupt) & _mask) >= _min_count_between_writes) {
AnnaBridge 188:bcfe06ba3d64 65 _set_interrupt_allowed = true;
AnnaBridge 188:bcfe06ba3d64 66 }
AnnaBridge 188:bcfe06ba3d64 67 }
AnnaBridge 188:bcfe06ba3d64 68
AnnaBridge 188:bcfe06ba3d64 69 _reset();
AnnaBridge 188:bcfe06ba3d64 70 _suspended = true;
AnnaBridge 188:bcfe06ba3d64 71
AnnaBridge 188:bcfe06ba3d64 72 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 73 }
AnnaBridge 188:bcfe06ba3d64 74
AnnaBridge 188:bcfe06ba3d64 75 void LowPowerTickerWrapper::resume()
AnnaBridge 188:bcfe06ba3d64 76 {
AnnaBridge 188:bcfe06ba3d64 77 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 78
AnnaBridge 188:bcfe06ba3d64 79 // Wait until rescheduling is allowed
AnnaBridge 188:bcfe06ba3d64 80 while (!_set_interrupt_allowed) {
AnnaBridge 188:bcfe06ba3d64 81 timestamp_t current = _intf->read();
AnnaBridge 188:bcfe06ba3d64 82 if (((current - _last_actual_set_interrupt) & _mask) >= _min_count_between_writes) {
AnnaBridge 188:bcfe06ba3d64 83 _set_interrupt_allowed = true;
AnnaBridge 188:bcfe06ba3d64 84 }
AnnaBridge 188:bcfe06ba3d64 85 }
AnnaBridge 188:bcfe06ba3d64 86
AnnaBridge 188:bcfe06ba3d64 87 _suspended = false;
AnnaBridge 188:bcfe06ba3d64 88
AnnaBridge 188:bcfe06ba3d64 89 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 90 }
AnnaBridge 188:bcfe06ba3d64 91
AnnaBridge 188:bcfe06ba3d64 92 bool LowPowerTickerWrapper::timeout_pending()
AnnaBridge 188:bcfe06ba3d64 93 {
AnnaBridge 188:bcfe06ba3d64 94 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 95
AnnaBridge 188:bcfe06ba3d64 96 bool pending = _pending_timeout;
AnnaBridge 188:bcfe06ba3d64 97
AnnaBridge 188:bcfe06ba3d64 98 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 99 return pending;
AnnaBridge 188:bcfe06ba3d64 100 }
AnnaBridge 188:bcfe06ba3d64 101
AnnaBridge 188:bcfe06ba3d64 102 void LowPowerTickerWrapper::init()
AnnaBridge 188:bcfe06ba3d64 103 {
AnnaBridge 188:bcfe06ba3d64 104 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 105
AnnaBridge 188:bcfe06ba3d64 106 _reset();
AnnaBridge 188:bcfe06ba3d64 107 _intf->init();
AnnaBridge 188:bcfe06ba3d64 108
AnnaBridge 188:bcfe06ba3d64 109 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 110 }
AnnaBridge 188:bcfe06ba3d64 111
AnnaBridge 188:bcfe06ba3d64 112 void LowPowerTickerWrapper::free()
AnnaBridge 188:bcfe06ba3d64 113 {
AnnaBridge 188:bcfe06ba3d64 114 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 115
AnnaBridge 188:bcfe06ba3d64 116 _reset();
AnnaBridge 188:bcfe06ba3d64 117 _intf->free();
AnnaBridge 188:bcfe06ba3d64 118
AnnaBridge 188:bcfe06ba3d64 119 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 120 }
AnnaBridge 188:bcfe06ba3d64 121
AnnaBridge 188:bcfe06ba3d64 122 uint32_t LowPowerTickerWrapper::read()
AnnaBridge 188:bcfe06ba3d64 123 {
AnnaBridge 188:bcfe06ba3d64 124 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 125
AnnaBridge 188:bcfe06ba3d64 126 timestamp_t current = _intf->read();
AnnaBridge 188:bcfe06ba3d64 127 if (!_suspended && _match_check(current)) {
AnnaBridge 188:bcfe06ba3d64 128 _intf->fire_interrupt();
AnnaBridge 188:bcfe06ba3d64 129 }
AnnaBridge 188:bcfe06ba3d64 130
AnnaBridge 188:bcfe06ba3d64 131 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 132 return current;
AnnaBridge 188:bcfe06ba3d64 133 }
AnnaBridge 188:bcfe06ba3d64 134
AnnaBridge 188:bcfe06ba3d64 135 void LowPowerTickerWrapper::set_interrupt(timestamp_t timestamp)
AnnaBridge 188:bcfe06ba3d64 136 {
AnnaBridge 188:bcfe06ba3d64 137 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 138
AnnaBridge 188:bcfe06ba3d64 139 _last_set_interrupt = _intf->read();
AnnaBridge 188:bcfe06ba3d64 140 _cur_match_time = timestamp;
AnnaBridge 188:bcfe06ba3d64 141 _pending_match = true;
AnnaBridge 188:bcfe06ba3d64 142 if (!_suspended) {
AnnaBridge 188:bcfe06ba3d64 143 _schedule_match(_last_set_interrupt);
AnnaBridge 188:bcfe06ba3d64 144 } else {
AnnaBridge 188:bcfe06ba3d64 145 _intf->set_interrupt(timestamp);
AnnaBridge 188:bcfe06ba3d64 146 _last_actual_set_interrupt = _last_set_interrupt;
AnnaBridge 188:bcfe06ba3d64 147 _set_interrupt_allowed = false;
AnnaBridge 188:bcfe06ba3d64 148 }
AnnaBridge 188:bcfe06ba3d64 149
AnnaBridge 188:bcfe06ba3d64 150 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 151 }
AnnaBridge 188:bcfe06ba3d64 152
AnnaBridge 188:bcfe06ba3d64 153 void LowPowerTickerWrapper::disable_interrupt()
AnnaBridge 188:bcfe06ba3d64 154 {
AnnaBridge 188:bcfe06ba3d64 155 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 156
AnnaBridge 188:bcfe06ba3d64 157 _intf->disable_interrupt();
AnnaBridge 188:bcfe06ba3d64 158
AnnaBridge 188:bcfe06ba3d64 159 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 160 }
AnnaBridge 188:bcfe06ba3d64 161
AnnaBridge 188:bcfe06ba3d64 162 void LowPowerTickerWrapper::clear_interrupt()
AnnaBridge 188:bcfe06ba3d64 163 {
AnnaBridge 188:bcfe06ba3d64 164 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 165
AnnaBridge 188:bcfe06ba3d64 166 _intf->clear_interrupt();
AnnaBridge 188:bcfe06ba3d64 167
AnnaBridge 188:bcfe06ba3d64 168 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 169 }
AnnaBridge 188:bcfe06ba3d64 170
AnnaBridge 188:bcfe06ba3d64 171 void LowPowerTickerWrapper::fire_interrupt()
AnnaBridge 188:bcfe06ba3d64 172 {
AnnaBridge 188:bcfe06ba3d64 173 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 174
AnnaBridge 188:bcfe06ba3d64 175 _pending_fire_now = 1;
AnnaBridge 188:bcfe06ba3d64 176 _intf->fire_interrupt();
AnnaBridge 188:bcfe06ba3d64 177
AnnaBridge 188:bcfe06ba3d64 178 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 179 }
AnnaBridge 188:bcfe06ba3d64 180
AnnaBridge 188:bcfe06ba3d64 181 const ticker_info_t *LowPowerTickerWrapper::get_info()
AnnaBridge 188:bcfe06ba3d64 182 {
AnnaBridge 188:bcfe06ba3d64 183
AnnaBridge 188:bcfe06ba3d64 184 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 185
AnnaBridge 188:bcfe06ba3d64 186 const ticker_info_t *info = _intf->get_info();
AnnaBridge 188:bcfe06ba3d64 187
AnnaBridge 188:bcfe06ba3d64 188 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 189 return info;
AnnaBridge 188:bcfe06ba3d64 190 }
AnnaBridge 188:bcfe06ba3d64 191
AnnaBridge 188:bcfe06ba3d64 192 void LowPowerTickerWrapper::_reset()
AnnaBridge 188:bcfe06ba3d64 193 {
AnnaBridge 188:bcfe06ba3d64 194 MBED_ASSERT(core_util_in_critical_section());
AnnaBridge 188:bcfe06ba3d64 195
AnnaBridge 188:bcfe06ba3d64 196 _timeout.detach();
AnnaBridge 188:bcfe06ba3d64 197 _pending_timeout = false;
AnnaBridge 188:bcfe06ba3d64 198 _pending_match = false;
AnnaBridge 188:bcfe06ba3d64 199 _pending_fire_now = false;
AnnaBridge 188:bcfe06ba3d64 200 _set_interrupt_allowed = true;
AnnaBridge 188:bcfe06ba3d64 201 _cur_match_time = 0;
AnnaBridge 188:bcfe06ba3d64 202 _last_set_interrupt = 0;
AnnaBridge 188:bcfe06ba3d64 203 _last_actual_set_interrupt = 0;
AnnaBridge 188:bcfe06ba3d64 204
AnnaBridge 188:bcfe06ba3d64 205 const ticker_info_t *info = _intf->get_info();
AnnaBridge 188:bcfe06ba3d64 206 if (info->bits >= 32) {
AnnaBridge 188:bcfe06ba3d64 207 _mask = 0xffffffff;
AnnaBridge 188:bcfe06ba3d64 208 } else {
AnnaBridge 188:bcfe06ba3d64 209 _mask = ((uint64_t)1 << info->bits) - 1;
AnnaBridge 188:bcfe06ba3d64 210 }
AnnaBridge 188:bcfe06ba3d64 211
AnnaBridge 188:bcfe06ba3d64 212 // Round us_per_tick up
AnnaBridge 188:bcfe06ba3d64 213 _us_per_tick = (1000000 + info->frequency - 1) / info->frequency;
AnnaBridge 188:bcfe06ba3d64 214 }
AnnaBridge 188:bcfe06ba3d64 215
AnnaBridge 188:bcfe06ba3d64 216 void LowPowerTickerWrapper::_timeout_handler()
AnnaBridge 188:bcfe06ba3d64 217 {
AnnaBridge 188:bcfe06ba3d64 218 core_util_critical_section_enter();
AnnaBridge 188:bcfe06ba3d64 219 _pending_timeout = false;
AnnaBridge 188:bcfe06ba3d64 220
AnnaBridge 188:bcfe06ba3d64 221 timestamp_t current = _intf->read();
AnnaBridge 188:bcfe06ba3d64 222 /* Add extra check for '_last_set_interrupt == _cur_match_time'
AnnaBridge 189:f392fc9709a3 223 *
AnnaBridge 188:bcfe06ba3d64 224 * When '_last_set_interrupt == _cur_match_time', _ticker_match_interval_passed sees it as
AnnaBridge 188:bcfe06ba3d64 225 * one-round interval rather than just-pass, so add extra check for it. In rare cases, we
AnnaBridge 188:bcfe06ba3d64 226 * may trap in _timeout_handler/_schedule_match loop. This check can break it.
AnnaBridge 188:bcfe06ba3d64 227 */
AnnaBridge 188:bcfe06ba3d64 228 if ((_last_set_interrupt == _cur_match_time) ||
AnnaBridge 189:f392fc9709a3 229 _ticker_match_interval_passed(_last_set_interrupt, current, _cur_match_time)) {
AnnaBridge 188:bcfe06ba3d64 230 _intf->fire_interrupt();
AnnaBridge 188:bcfe06ba3d64 231 } else {
AnnaBridge 188:bcfe06ba3d64 232 _schedule_match(current);
AnnaBridge 188:bcfe06ba3d64 233 }
AnnaBridge 188:bcfe06ba3d64 234
AnnaBridge 188:bcfe06ba3d64 235 core_util_critical_section_exit();
AnnaBridge 188:bcfe06ba3d64 236 }
AnnaBridge 188:bcfe06ba3d64 237
AnnaBridge 188:bcfe06ba3d64 238 bool LowPowerTickerWrapper::_match_check(timestamp_t current)
AnnaBridge 188:bcfe06ba3d64 239 {
AnnaBridge 188:bcfe06ba3d64 240 MBED_ASSERT(core_util_in_critical_section());
AnnaBridge 188:bcfe06ba3d64 241
AnnaBridge 188:bcfe06ba3d64 242 if (!_pending_match) {
AnnaBridge 188:bcfe06ba3d64 243 return false;
AnnaBridge 188:bcfe06ba3d64 244 }
AnnaBridge 188:bcfe06ba3d64 245 /* Add extra check for '_last_set_interrupt == _cur_match_time' as above */
AnnaBridge 188:bcfe06ba3d64 246 return (_last_set_interrupt == _cur_match_time) ||
AnnaBridge 189:f392fc9709a3 247 _ticker_match_interval_passed(_last_set_interrupt, current, _cur_match_time);
AnnaBridge 188:bcfe06ba3d64 248 }
AnnaBridge 188:bcfe06ba3d64 249
AnnaBridge 188:bcfe06ba3d64 250 uint32_t LowPowerTickerWrapper::_lp_ticks_to_us(uint32_t ticks)
AnnaBridge 188:bcfe06ba3d64 251 {
AnnaBridge 188:bcfe06ba3d64 252 MBED_ASSERT(core_util_in_critical_section());
AnnaBridge 188:bcfe06ba3d64 253
AnnaBridge 188:bcfe06ba3d64 254 // Add 4 microseconds to round up the micro second ticker time (which has a frequency of at least 250KHz - 4us period)
AnnaBridge 188:bcfe06ba3d64 255 return _us_per_tick * ticks + 4;
AnnaBridge 188:bcfe06ba3d64 256 }
AnnaBridge 188:bcfe06ba3d64 257
AnnaBridge 188:bcfe06ba3d64 258 void LowPowerTickerWrapper::_schedule_match(timestamp_t current)
AnnaBridge 188:bcfe06ba3d64 259 {
AnnaBridge 188:bcfe06ba3d64 260 MBED_ASSERT(core_util_in_critical_section());
AnnaBridge 188:bcfe06ba3d64 261
AnnaBridge 188:bcfe06ba3d64 262 // Check if _intf->set_interrupt is allowed
AnnaBridge 188:bcfe06ba3d64 263 if (!_set_interrupt_allowed) {
AnnaBridge 188:bcfe06ba3d64 264 if (((current - _last_actual_set_interrupt) & _mask) >= _min_count_between_writes) {
AnnaBridge 188:bcfe06ba3d64 265 _set_interrupt_allowed = true;
AnnaBridge 188:bcfe06ba3d64 266 }
AnnaBridge 188:bcfe06ba3d64 267 }
AnnaBridge 188:bcfe06ba3d64 268
AnnaBridge 188:bcfe06ba3d64 269 uint32_t cycles_until_match = (_cur_match_time - current) & _mask;
AnnaBridge 188:bcfe06ba3d64 270 bool too_close = cycles_until_match < _min_count_until_match;
AnnaBridge 188:bcfe06ba3d64 271
AnnaBridge 188:bcfe06ba3d64 272 if (!_set_interrupt_allowed) {
AnnaBridge 188:bcfe06ba3d64 273
AnnaBridge 188:bcfe06ba3d64 274 // Can't use _intf->set_interrupt so use microsecond Timeout instead
AnnaBridge 188:bcfe06ba3d64 275
AnnaBridge 188:bcfe06ba3d64 276 // Speed optimization - if a timer has already been scheduled
AnnaBridge 188:bcfe06ba3d64 277 // then don't schedule it again.
AnnaBridge 188:bcfe06ba3d64 278 if (!_pending_timeout) {
AnnaBridge 188:bcfe06ba3d64 279 uint32_t ticks = cycles_until_match < _min_count_until_match ? cycles_until_match : _min_count_until_match;
AnnaBridge 188:bcfe06ba3d64 280 _timeout.attach_us(mbed::callback(this, &LowPowerTickerWrapper::_timeout_handler), _lp_ticks_to_us(ticks));
AnnaBridge 188:bcfe06ba3d64 281 _pending_timeout = true;
AnnaBridge 188:bcfe06ba3d64 282 }
AnnaBridge 188:bcfe06ba3d64 283 return;
AnnaBridge 188:bcfe06ba3d64 284 }
AnnaBridge 188:bcfe06ba3d64 285
AnnaBridge 188:bcfe06ba3d64 286 if (!too_close) {
AnnaBridge 188:bcfe06ba3d64 287
AnnaBridge 188:bcfe06ba3d64 288 // Schedule LP ticker
AnnaBridge 188:bcfe06ba3d64 289 _intf->set_interrupt(_cur_match_time);
AnnaBridge 188:bcfe06ba3d64 290 current = _intf->read();
AnnaBridge 188:bcfe06ba3d64 291 _last_actual_set_interrupt = current;
AnnaBridge 188:bcfe06ba3d64 292 _set_interrupt_allowed = false;
AnnaBridge 188:bcfe06ba3d64 293
AnnaBridge 188:bcfe06ba3d64 294 // Check for overflow
AnnaBridge 188:bcfe06ba3d64 295 uint32_t new_cycles_until_match = (_cur_match_time - current) & _mask;
AnnaBridge 188:bcfe06ba3d64 296 if (new_cycles_until_match > cycles_until_match) {
AnnaBridge 188:bcfe06ba3d64 297 // Overflow so fire now
AnnaBridge 188:bcfe06ba3d64 298 _intf->fire_interrupt();
AnnaBridge 188:bcfe06ba3d64 299 return;
AnnaBridge 188:bcfe06ba3d64 300 }
AnnaBridge 188:bcfe06ba3d64 301
AnnaBridge 188:bcfe06ba3d64 302 // Update variables with new time
AnnaBridge 188:bcfe06ba3d64 303 cycles_until_match = new_cycles_until_match;
AnnaBridge 188:bcfe06ba3d64 304 too_close = cycles_until_match < _min_count_until_match;
AnnaBridge 188:bcfe06ba3d64 305 }
AnnaBridge 188:bcfe06ba3d64 306
AnnaBridge 188:bcfe06ba3d64 307 if (too_close) {
AnnaBridge 188:bcfe06ba3d64 308
AnnaBridge 188:bcfe06ba3d64 309 // Low power ticker incremented to less than _min_count_until_match
AnnaBridge 188:bcfe06ba3d64 310 // so low power ticker may not fire. Use Timeout to ensure it does fire.
AnnaBridge 188:bcfe06ba3d64 311 uint32_t ticks = cycles_until_match < _min_count_until_match ? cycles_until_match : _min_count_until_match;
AnnaBridge 188:bcfe06ba3d64 312 _timeout.attach_us(mbed::callback(this, &LowPowerTickerWrapper::_timeout_handler), _lp_ticks_to_us(ticks));
AnnaBridge 188:bcfe06ba3d64 313 _pending_timeout = true;
AnnaBridge 188:bcfe06ba3d64 314 return;
AnnaBridge 188:bcfe06ba3d64 315 }
AnnaBridge 188:bcfe06ba3d64 316 }