Mouse code for the MacroRat
mbed-dev/targets/TARGET_NORDIC/TARGET_NRF5_SDK13/us_ticker.c@46:b156ef445742, 2017-06-03 (annotated)
- Committer:
- sahilmgandhi
- Date:
- Sat Jun 03 00:22:44 2017 +0000
- Revision:
- 46:b156ef445742
- Parent:
- 18:6a4db94011d3
Final code for internal battlebot competition.
Who changed what in which revision?
User | Revision | Line number | New contents of line |
---|---|---|---|
sahilmgandhi | 18:6a4db94011d3 | 1 | /* |
sahilmgandhi | 18:6a4db94011d3 | 2 | * Copyright (c) 2013 Nordic Semiconductor ASA |
sahilmgandhi | 18:6a4db94011d3 | 3 | * All rights reserved. |
sahilmgandhi | 18:6a4db94011d3 | 4 | * |
sahilmgandhi | 18:6a4db94011d3 | 5 | * Redistribution and use in source and binary forms, with or without modification, |
sahilmgandhi | 18:6a4db94011d3 | 6 | * are permitted provided that the following conditions are met: |
sahilmgandhi | 18:6a4db94011d3 | 7 | * |
sahilmgandhi | 18:6a4db94011d3 | 8 | * 1. Redistributions of source code must retain the above copyright notice, this list |
sahilmgandhi | 18:6a4db94011d3 | 9 | * of conditions and the following disclaimer. |
sahilmgandhi | 18:6a4db94011d3 | 10 | * |
sahilmgandhi | 18:6a4db94011d3 | 11 | * 2. Redistributions in binary form, except as embedded into a Nordic Semiconductor ASA |
sahilmgandhi | 18:6a4db94011d3 | 12 | * integrated circuit in a product or a software update for such product, must reproduce |
sahilmgandhi | 18:6a4db94011d3 | 13 | * the above copyright notice, this list of conditions and the following disclaimer in |
sahilmgandhi | 18:6a4db94011d3 | 14 | * the documentation and/or other materials provided with the distribution. |
sahilmgandhi | 18:6a4db94011d3 | 15 | * |
sahilmgandhi | 18:6a4db94011d3 | 16 | * 3. Neither the name of Nordic Semiconductor ASA nor the names of its contributors may be |
sahilmgandhi | 18:6a4db94011d3 | 17 | * used to endorse or promote products derived from this software without specific prior |
sahilmgandhi | 18:6a4db94011d3 | 18 | * written permission. |
sahilmgandhi | 18:6a4db94011d3 | 19 | * |
sahilmgandhi | 18:6a4db94011d3 | 20 | * 4. This software, with or without modification, must only be used with a |
sahilmgandhi | 18:6a4db94011d3 | 21 | * Nordic Semiconductor ASA integrated circuit. |
sahilmgandhi | 18:6a4db94011d3 | 22 | * |
sahilmgandhi | 18:6a4db94011d3 | 23 | * 5. Any software provided in binary or object form under this license must not be reverse |
sahilmgandhi | 18:6a4db94011d3 | 24 | * engineered, decompiled, modified and/or disassembled. |
sahilmgandhi | 18:6a4db94011d3 | 25 | * |
sahilmgandhi | 18:6a4db94011d3 | 26 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND |
sahilmgandhi | 18:6a4db94011d3 | 27 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED |
sahilmgandhi | 18:6a4db94011d3 | 28 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
sahilmgandhi | 18:6a4db94011d3 | 29 | * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR |
sahilmgandhi | 18:6a4db94011d3 | 30 | * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES |
sahilmgandhi | 18:6a4db94011d3 | 31 | * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
sahilmgandhi | 18:6a4db94011d3 | 32 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON |
sahilmgandhi | 18:6a4db94011d3 | 33 | * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
sahilmgandhi | 18:6a4db94011d3 | 34 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
sahilmgandhi | 18:6a4db94011d3 | 35 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
sahilmgandhi | 18:6a4db94011d3 | 36 | * |
sahilmgandhi | 18:6a4db94011d3 | 37 | */ |
sahilmgandhi | 18:6a4db94011d3 | 38 | |
sahilmgandhi | 18:6a4db94011d3 | 39 | #include "us_ticker_api.h" |
sahilmgandhi | 18:6a4db94011d3 | 40 | #include "common_rtc.h" |
sahilmgandhi | 18:6a4db94011d3 | 41 | #include "app_util.h" |
sahilmgandhi | 18:6a4db94011d3 | 42 | #include "nrf_drv_common.h" |
sahilmgandhi | 18:6a4db94011d3 | 43 | #include "lp_ticker_api.h" |
sahilmgandhi | 18:6a4db94011d3 | 44 | #include "mbed_critical.h" |
sahilmgandhi | 18:6a4db94011d3 | 45 | |
sahilmgandhi | 18:6a4db94011d3 | 46 | #if defined(NRF52_ERRATA_20) |
sahilmgandhi | 18:6a4db94011d3 | 47 | #include "softdevice_handler.h" |
sahilmgandhi | 18:6a4db94011d3 | 48 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 49 | |
sahilmgandhi | 18:6a4db94011d3 | 50 | //------------------------------------------------------------------------------ |
sahilmgandhi | 18:6a4db94011d3 | 51 | // Common stuff used also by lp_ticker and rtc_api (see "common_rtc.h"). |
sahilmgandhi | 18:6a4db94011d3 | 52 | // |
sahilmgandhi | 18:6a4db94011d3 | 53 | #include "app_util_platform.h" |
sahilmgandhi | 18:6a4db94011d3 | 54 | |
sahilmgandhi | 18:6a4db94011d3 | 55 | bool m_common_rtc_enabled = false; |
sahilmgandhi | 18:6a4db94011d3 | 56 | uint32_t volatile m_common_rtc_overflows = 0; |
sahilmgandhi | 18:6a4db94011d3 | 57 | |
sahilmgandhi | 18:6a4db94011d3 | 58 | __STATIC_INLINE void rtc_ovf_event_check(void) |
sahilmgandhi | 18:6a4db94011d3 | 59 | { |
sahilmgandhi | 18:6a4db94011d3 | 60 | if (nrf_rtc_event_pending(COMMON_RTC_INSTANCE, NRF_RTC_EVENT_OVERFLOW)) { |
sahilmgandhi | 18:6a4db94011d3 | 61 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, NRF_RTC_EVENT_OVERFLOW); |
sahilmgandhi | 18:6a4db94011d3 | 62 | // Don't disable this event. It shall occur periodically. |
sahilmgandhi | 18:6a4db94011d3 | 63 | |
sahilmgandhi | 18:6a4db94011d3 | 64 | ++m_common_rtc_overflows; |
sahilmgandhi | 18:6a4db94011d3 | 65 | } |
sahilmgandhi | 18:6a4db94011d3 | 66 | } |
sahilmgandhi | 18:6a4db94011d3 | 67 | |
sahilmgandhi | 18:6a4db94011d3 | 68 | #if defined(TARGET_MCU_NRF51822) |
sahilmgandhi | 18:6a4db94011d3 | 69 | void common_rtc_irq_handler(void) |
sahilmgandhi | 18:6a4db94011d3 | 70 | #else |
sahilmgandhi | 18:6a4db94011d3 | 71 | void COMMON_RTC_IRQ_HANDLER(void) |
sahilmgandhi | 18:6a4db94011d3 | 72 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 73 | { |
sahilmgandhi | 18:6a4db94011d3 | 74 | |
sahilmgandhi | 18:6a4db94011d3 | 75 | rtc_ovf_event_check(); |
sahilmgandhi | 18:6a4db94011d3 | 76 | |
sahilmgandhi | 18:6a4db94011d3 | 77 | if (nrf_rtc_event_pending(COMMON_RTC_INSTANCE, US_TICKER_EVENT)) { |
sahilmgandhi | 18:6a4db94011d3 | 78 | us_ticker_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 79 | } |
sahilmgandhi | 18:6a4db94011d3 | 80 | |
sahilmgandhi | 18:6a4db94011d3 | 81 | #if DEVICE_LOWPOWERTIMER |
sahilmgandhi | 18:6a4db94011d3 | 82 | if (nrf_rtc_event_pending(COMMON_RTC_INSTANCE, LP_TICKER_EVENT)) { |
sahilmgandhi | 18:6a4db94011d3 | 83 | |
sahilmgandhi | 18:6a4db94011d3 | 84 | lp_ticker_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 85 | } |
sahilmgandhi | 18:6a4db94011d3 | 86 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 87 | |
sahilmgandhi | 18:6a4db94011d3 | 88 | } |
sahilmgandhi | 18:6a4db94011d3 | 89 | |
sahilmgandhi | 18:6a4db94011d3 | 90 | // Function for fix errata 20: RTC Register values are invalid |
sahilmgandhi | 18:6a4db94011d3 | 91 | __STATIC_INLINE void errata_20(void) |
sahilmgandhi | 18:6a4db94011d3 | 92 | { |
sahilmgandhi | 18:6a4db94011d3 | 93 | #if defined(NRF52_ERRATA_20) |
sahilmgandhi | 18:6a4db94011d3 | 94 | if (!softdevice_handler_is_enabled()) |
sahilmgandhi | 18:6a4db94011d3 | 95 | { |
sahilmgandhi | 18:6a4db94011d3 | 96 | NRF_CLOCK->EVENTS_LFCLKSTARTED = 0; |
sahilmgandhi | 18:6a4db94011d3 | 97 | NRF_CLOCK->TASKS_LFCLKSTART = 1; |
sahilmgandhi | 18:6a4db94011d3 | 98 | |
sahilmgandhi | 18:6a4db94011d3 | 99 | while (NRF_CLOCK->EVENTS_LFCLKSTARTED == 0) |
sahilmgandhi | 18:6a4db94011d3 | 100 | { |
sahilmgandhi | 18:6a4db94011d3 | 101 | } |
sahilmgandhi | 18:6a4db94011d3 | 102 | } |
sahilmgandhi | 18:6a4db94011d3 | 103 | NRF_RTC1->TASKS_STOP = 0; |
sahilmgandhi | 18:6a4db94011d3 | 104 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 105 | } |
sahilmgandhi | 18:6a4db94011d3 | 106 | |
sahilmgandhi | 18:6a4db94011d3 | 107 | #if (defined (__ICCARM__)) && defined(TARGET_MCU_NRF51822)//IAR |
sahilmgandhi | 18:6a4db94011d3 | 108 | __stackless __task |
sahilmgandhi | 18:6a4db94011d3 | 109 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 110 | void RTC1_IRQHandler(void); |
sahilmgandhi | 18:6a4db94011d3 | 111 | |
sahilmgandhi | 18:6a4db94011d3 | 112 | void common_rtc_init(void) |
sahilmgandhi | 18:6a4db94011d3 | 113 | { |
sahilmgandhi | 18:6a4db94011d3 | 114 | if (m_common_rtc_enabled) { |
sahilmgandhi | 18:6a4db94011d3 | 115 | return; |
sahilmgandhi | 18:6a4db94011d3 | 116 | } |
sahilmgandhi | 18:6a4db94011d3 | 117 | |
sahilmgandhi | 18:6a4db94011d3 | 118 | errata_20(); |
sahilmgandhi | 18:6a4db94011d3 | 119 | |
sahilmgandhi | 18:6a4db94011d3 | 120 | NVIC_SetVector(RTC1_IRQn, (uint32_t)RTC1_IRQHandler); |
sahilmgandhi | 18:6a4db94011d3 | 121 | |
sahilmgandhi | 18:6a4db94011d3 | 122 | // RTC is driven by the low frequency (32.768 kHz) clock, a proper request |
sahilmgandhi | 18:6a4db94011d3 | 123 | // must be made to have it running. |
sahilmgandhi | 18:6a4db94011d3 | 124 | // Currently this clock is started in 'SystemInit' (see "system_nrf51.c" |
sahilmgandhi | 18:6a4db94011d3 | 125 | // or "system_nrf52.c", respectively). |
sahilmgandhi | 18:6a4db94011d3 | 126 | |
sahilmgandhi | 18:6a4db94011d3 | 127 | nrf_rtc_prescaler_set(COMMON_RTC_INSTANCE, 0); |
sahilmgandhi | 18:6a4db94011d3 | 128 | |
sahilmgandhi | 18:6a4db94011d3 | 129 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, US_TICKER_EVENT); |
sahilmgandhi | 18:6a4db94011d3 | 130 | #if defined(TARGET_MCU_NRF51822) |
sahilmgandhi | 18:6a4db94011d3 | 131 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, OS_TICK_EVENT); |
sahilmgandhi | 18:6a4db94011d3 | 132 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 133 | #if DEVICE_LOWPOWERTIMER |
sahilmgandhi | 18:6a4db94011d3 | 134 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, LP_TICKER_EVENT); |
sahilmgandhi | 18:6a4db94011d3 | 135 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 136 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, NRF_RTC_EVENT_OVERFLOW); |
sahilmgandhi | 18:6a4db94011d3 | 137 | |
sahilmgandhi | 18:6a4db94011d3 | 138 | // Interrupts on all related events are enabled permanently. Particular |
sahilmgandhi | 18:6a4db94011d3 | 139 | // events will be enabled or disabled as needed (such approach is more |
sahilmgandhi | 18:6a4db94011d3 | 140 | // energy efficient). |
sahilmgandhi | 18:6a4db94011d3 | 141 | nrf_rtc_int_enable(COMMON_RTC_INSTANCE, |
sahilmgandhi | 18:6a4db94011d3 | 142 | #if DEVICE_LOWPOWERTIMER |
sahilmgandhi | 18:6a4db94011d3 | 143 | LP_TICKER_INT_MASK | |
sahilmgandhi | 18:6a4db94011d3 | 144 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 145 | US_TICKER_INT_MASK | |
sahilmgandhi | 18:6a4db94011d3 | 146 | NRF_RTC_INT_OVERFLOW_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 147 | |
sahilmgandhi | 18:6a4db94011d3 | 148 | // This event is enabled permanently, since overflow indications are needed |
sahilmgandhi | 18:6a4db94011d3 | 149 | // continuously. |
sahilmgandhi | 18:6a4db94011d3 | 150 | nrf_rtc_event_enable(COMMON_RTC_INSTANCE, NRF_RTC_INT_OVERFLOW_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 151 | // All other relevant events are initially disabled. |
sahilmgandhi | 18:6a4db94011d3 | 152 | nrf_rtc_event_disable(COMMON_RTC_INSTANCE, |
sahilmgandhi | 18:6a4db94011d3 | 153 | #if defined(TARGET_MCU_NRF51822) |
sahilmgandhi | 18:6a4db94011d3 | 154 | OS_TICK_INT_MASK | |
sahilmgandhi | 18:6a4db94011d3 | 155 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 156 | #if DEVICE_LOWPOWERTIMER |
sahilmgandhi | 18:6a4db94011d3 | 157 | LP_TICKER_INT_MASK | |
sahilmgandhi | 18:6a4db94011d3 | 158 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 159 | US_TICKER_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 160 | |
sahilmgandhi | 18:6a4db94011d3 | 161 | nrf_drv_common_irq_enable(nrf_drv_get_IRQn(COMMON_RTC_INSTANCE), |
sahilmgandhi | 18:6a4db94011d3 | 162 | #ifdef NRF51 |
sahilmgandhi | 18:6a4db94011d3 | 163 | APP_IRQ_PRIORITY_LOW |
sahilmgandhi | 18:6a4db94011d3 | 164 | #elif defined(NRF52) || defined(NRF52840_XXAA) |
sahilmgandhi | 18:6a4db94011d3 | 165 | APP_IRQ_PRIORITY_LOWEST |
sahilmgandhi | 18:6a4db94011d3 | 166 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 167 | ); |
sahilmgandhi | 18:6a4db94011d3 | 168 | |
sahilmgandhi | 18:6a4db94011d3 | 169 | nrf_rtc_task_trigger(COMMON_RTC_INSTANCE, NRF_RTC_TASK_START); |
sahilmgandhi | 18:6a4db94011d3 | 170 | |
sahilmgandhi | 18:6a4db94011d3 | 171 | m_common_rtc_enabled = true; |
sahilmgandhi | 18:6a4db94011d3 | 172 | } |
sahilmgandhi | 18:6a4db94011d3 | 173 | |
sahilmgandhi | 18:6a4db94011d3 | 174 | __STATIC_INLINE void rtc_ovf_event_safe_check(void) |
sahilmgandhi | 18:6a4db94011d3 | 175 | { |
sahilmgandhi | 18:6a4db94011d3 | 176 | core_util_critical_section_enter(); |
sahilmgandhi | 18:6a4db94011d3 | 177 | |
sahilmgandhi | 18:6a4db94011d3 | 178 | rtc_ovf_event_check(); |
sahilmgandhi | 18:6a4db94011d3 | 179 | |
sahilmgandhi | 18:6a4db94011d3 | 180 | core_util_critical_section_exit(); |
sahilmgandhi | 18:6a4db94011d3 | 181 | } |
sahilmgandhi | 18:6a4db94011d3 | 182 | |
sahilmgandhi | 18:6a4db94011d3 | 183 | |
sahilmgandhi | 18:6a4db94011d3 | 184 | uint32_t common_rtc_32bit_ticks_get(void) |
sahilmgandhi | 18:6a4db94011d3 | 185 | { |
sahilmgandhi | 18:6a4db94011d3 | 186 | uint32_t ticks; |
sahilmgandhi | 18:6a4db94011d3 | 187 | uint32_t prev_overflows; |
sahilmgandhi | 18:6a4db94011d3 | 188 | |
sahilmgandhi | 18:6a4db94011d3 | 189 | do { |
sahilmgandhi | 18:6a4db94011d3 | 190 | prev_overflows = m_common_rtc_overflows; |
sahilmgandhi | 18:6a4db94011d3 | 191 | |
sahilmgandhi | 18:6a4db94011d3 | 192 | ticks = nrf_rtc_counter_get(COMMON_RTC_INSTANCE); |
sahilmgandhi | 18:6a4db94011d3 | 193 | // The counter used for time measurements is less than 32 bit wide, |
sahilmgandhi | 18:6a4db94011d3 | 194 | // so its value is complemented with the number of registered overflows |
sahilmgandhi | 18:6a4db94011d3 | 195 | // of the counter. |
sahilmgandhi | 18:6a4db94011d3 | 196 | ticks += (m_common_rtc_overflows << RTC_COUNTER_BITS); |
sahilmgandhi | 18:6a4db94011d3 | 197 | |
sahilmgandhi | 18:6a4db94011d3 | 198 | // Check in case that OVF occurred during execution of a RTC handler (apply if call was from RTC handler) |
sahilmgandhi | 18:6a4db94011d3 | 199 | // m_common_rtc_overflows might been updated in this call. |
sahilmgandhi | 18:6a4db94011d3 | 200 | rtc_ovf_event_safe_check(); |
sahilmgandhi | 18:6a4db94011d3 | 201 | |
sahilmgandhi | 18:6a4db94011d3 | 202 | // If call was made from a low priority level m_common_rtc_overflows might have been updated in RTC handler. |
sahilmgandhi | 18:6a4db94011d3 | 203 | } while (m_common_rtc_overflows != prev_overflows); |
sahilmgandhi | 18:6a4db94011d3 | 204 | |
sahilmgandhi | 18:6a4db94011d3 | 205 | return ticks; |
sahilmgandhi | 18:6a4db94011d3 | 206 | } |
sahilmgandhi | 18:6a4db94011d3 | 207 | |
sahilmgandhi | 18:6a4db94011d3 | 208 | uint64_t common_rtc_64bit_us_get(void) |
sahilmgandhi | 18:6a4db94011d3 | 209 | { |
sahilmgandhi | 18:6a4db94011d3 | 210 | uint32_t ticks = common_rtc_32bit_ticks_get(); |
sahilmgandhi | 18:6a4db94011d3 | 211 | // [ticks -> microseconds] |
sahilmgandhi | 18:6a4db94011d3 | 212 | return ROUNDED_DIV(((uint64_t)ticks) * 1000000, RTC_INPUT_FREQ); |
sahilmgandhi | 18:6a4db94011d3 | 213 | } |
sahilmgandhi | 18:6a4db94011d3 | 214 | |
sahilmgandhi | 18:6a4db94011d3 | 215 | void common_rtc_set_interrupt(uint32_t us_timestamp, uint32_t cc_channel, |
sahilmgandhi | 18:6a4db94011d3 | 216 | uint32_t int_mask) |
sahilmgandhi | 18:6a4db94011d3 | 217 | { |
sahilmgandhi | 18:6a4db94011d3 | 218 | // The internal counter is clocked with a frequency that cannot be easily |
sahilmgandhi | 18:6a4db94011d3 | 219 | // multiplied to 1 MHz, therefore besides the translation of values |
sahilmgandhi | 18:6a4db94011d3 | 220 | // (microsecond <-> ticks) a special care of overflows handling must be |
sahilmgandhi | 18:6a4db94011d3 | 221 | // taken. Here the 32-bit timestamp value is complemented with information |
sahilmgandhi | 18:6a4db94011d3 | 222 | // about current the system up time of (ticks + number of overflows of tick |
sahilmgandhi | 18:6a4db94011d3 | 223 | // counter on upper bits, converted to microseconds), and such 64-bit value |
sahilmgandhi | 18:6a4db94011d3 | 224 | // is then translated to counter ticks. Finally, the lower 24 bits of thus |
sahilmgandhi | 18:6a4db94011d3 | 225 | // calculated value is written to the counter compare register to prepare |
sahilmgandhi | 18:6a4db94011d3 | 226 | // the interrupt generation. |
sahilmgandhi | 18:6a4db94011d3 | 227 | uint64_t current_time64 = common_rtc_64bit_us_get(); |
sahilmgandhi | 18:6a4db94011d3 | 228 | // [add upper 32 bits from the current time to the timestamp value] |
sahilmgandhi | 18:6a4db94011d3 | 229 | uint64_t timestamp64 = us_timestamp + |
sahilmgandhi | 18:6a4db94011d3 | 230 | (current_time64 & ~(uint64_t)0xFFFFFFFF); |
sahilmgandhi | 18:6a4db94011d3 | 231 | // [if the original timestamp value happens to be after the 32 bit counter |
sahilmgandhi | 18:6a4db94011d3 | 232 | // of microsends overflows, correct the upper 32 bits accordingly] |
sahilmgandhi | 18:6a4db94011d3 | 233 | if (us_timestamp < (uint32_t)(current_time64 & 0xFFFFFFFF)) { |
sahilmgandhi | 18:6a4db94011d3 | 234 | timestamp64 += ((uint64_t)1 << 32); |
sahilmgandhi | 18:6a4db94011d3 | 235 | } |
sahilmgandhi | 18:6a4db94011d3 | 236 | // [microseconds -> ticks, always round the result up to avoid too early |
sahilmgandhi | 18:6a4db94011d3 | 237 | // interrupt generation] |
sahilmgandhi | 18:6a4db94011d3 | 238 | uint32_t compare_value = |
sahilmgandhi | 18:6a4db94011d3 | 239 | (uint32_t)CEIL_DIV((timestamp64) * RTC_INPUT_FREQ, 1000000); |
sahilmgandhi | 18:6a4db94011d3 | 240 | |
sahilmgandhi | 18:6a4db94011d3 | 241 | core_util_critical_section_enter(); |
sahilmgandhi | 18:6a4db94011d3 | 242 | // The COMPARE event occurs when the value in compare register is N and |
sahilmgandhi | 18:6a4db94011d3 | 243 | // the counter value changes from N-1 to N. Therefore, the minimal safe |
sahilmgandhi | 18:6a4db94011d3 | 244 | // difference between the compare value to be set and the current counter |
sahilmgandhi | 18:6a4db94011d3 | 245 | // value is 2 ticks. This guarantees that the compare trigger is properly |
sahilmgandhi | 18:6a4db94011d3 | 246 | // setup before the compare condition occurs. |
sahilmgandhi | 18:6a4db94011d3 | 247 | uint32_t closest_safe_compare = common_rtc_32bit_ticks_get() + 2; |
sahilmgandhi | 18:6a4db94011d3 | 248 | if ((int)(compare_value - closest_safe_compare) <= 0) { |
sahilmgandhi | 18:6a4db94011d3 | 249 | compare_value = closest_safe_compare; |
sahilmgandhi | 18:6a4db94011d3 | 250 | } |
sahilmgandhi | 18:6a4db94011d3 | 251 | |
sahilmgandhi | 18:6a4db94011d3 | 252 | nrf_rtc_cc_set(COMMON_RTC_INSTANCE, cc_channel, RTC_WRAP(compare_value)); |
sahilmgandhi | 18:6a4db94011d3 | 253 | nrf_rtc_event_enable(COMMON_RTC_INSTANCE, int_mask); |
sahilmgandhi | 18:6a4db94011d3 | 254 | core_util_critical_section_exit(); |
sahilmgandhi | 18:6a4db94011d3 | 255 | } |
sahilmgandhi | 18:6a4db94011d3 | 256 | //------------------------------------------------------------------------------ |
sahilmgandhi | 18:6a4db94011d3 | 257 | |
sahilmgandhi | 18:6a4db94011d3 | 258 | |
sahilmgandhi | 18:6a4db94011d3 | 259 | void us_ticker_init(void) |
sahilmgandhi | 18:6a4db94011d3 | 260 | { |
sahilmgandhi | 18:6a4db94011d3 | 261 | common_rtc_init(); |
sahilmgandhi | 18:6a4db94011d3 | 262 | } |
sahilmgandhi | 18:6a4db94011d3 | 263 | |
sahilmgandhi | 18:6a4db94011d3 | 264 | uint32_t us_ticker_read() |
sahilmgandhi | 18:6a4db94011d3 | 265 | { |
sahilmgandhi | 18:6a4db94011d3 | 266 | us_ticker_init(); |
sahilmgandhi | 18:6a4db94011d3 | 267 | return (uint32_t)common_rtc_64bit_us_get(); |
sahilmgandhi | 18:6a4db94011d3 | 268 | } |
sahilmgandhi | 18:6a4db94011d3 | 269 | |
sahilmgandhi | 18:6a4db94011d3 | 270 | void us_ticker_set_interrupt(timestamp_t timestamp) |
sahilmgandhi | 18:6a4db94011d3 | 271 | { |
sahilmgandhi | 18:6a4db94011d3 | 272 | common_rtc_set_interrupt(timestamp, |
sahilmgandhi | 18:6a4db94011d3 | 273 | US_TICKER_CC_CHANNEL, US_TICKER_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 274 | } |
sahilmgandhi | 18:6a4db94011d3 | 275 | |
sahilmgandhi | 18:6a4db94011d3 | 276 | void us_ticker_disable_interrupt(void) |
sahilmgandhi | 18:6a4db94011d3 | 277 | { |
sahilmgandhi | 18:6a4db94011d3 | 278 | nrf_rtc_event_disable(COMMON_RTC_INSTANCE, US_TICKER_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 279 | } |
sahilmgandhi | 18:6a4db94011d3 | 280 | |
sahilmgandhi | 18:6a4db94011d3 | 281 | void us_ticker_clear_interrupt(void) |
sahilmgandhi | 18:6a4db94011d3 | 282 | { |
sahilmgandhi | 18:6a4db94011d3 | 283 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, US_TICKER_EVENT); |
sahilmgandhi | 18:6a4db94011d3 | 284 | } |
sahilmgandhi | 18:6a4db94011d3 | 285 | |
sahilmgandhi | 18:6a4db94011d3 | 286 | |
sahilmgandhi | 18:6a4db94011d3 | 287 | // Since there is no SysTick on NRF51, the RTC1 channel 1 is used as an |
sahilmgandhi | 18:6a4db94011d3 | 288 | // alternative source of RTOS ticks. |
sahilmgandhi | 18:6a4db94011d3 | 289 | #if defined(TARGET_MCU_NRF51822) |
sahilmgandhi | 18:6a4db94011d3 | 290 | |
sahilmgandhi | 18:6a4db94011d3 | 291 | #include "mbed_toolchain.h" |
sahilmgandhi | 18:6a4db94011d3 | 292 | |
sahilmgandhi | 18:6a4db94011d3 | 293 | |
sahilmgandhi | 18:6a4db94011d3 | 294 | #define MAX_RTC_COUNTER_VAL ((1uL << RTC_COUNTER_BITS) - 1) |
sahilmgandhi | 18:6a4db94011d3 | 295 | |
sahilmgandhi | 18:6a4db94011d3 | 296 | /** |
sahilmgandhi | 18:6a4db94011d3 | 297 | * The value previously set in the capture compare register of channel 1 |
sahilmgandhi | 18:6a4db94011d3 | 298 | */ |
sahilmgandhi | 18:6a4db94011d3 | 299 | static uint32_t previous_tick_cc_value = 0; |
sahilmgandhi | 18:6a4db94011d3 | 300 | |
sahilmgandhi | 18:6a4db94011d3 | 301 | /* |
sahilmgandhi | 18:6a4db94011d3 | 302 | RTX provide the following definitions which are used by the tick code: |
sahilmgandhi | 18:6a4db94011d3 | 303 | * os_trv: The number (minus 1) of clock cycle between two tick. |
sahilmgandhi | 18:6a4db94011d3 | 304 | * os_clockrate: Time duration between two ticks (in us). |
sahilmgandhi | 18:6a4db94011d3 | 305 | * OS_Tick_Handler: The function which handle a tick event. |
sahilmgandhi | 18:6a4db94011d3 | 306 | This function is special because it never returns. |
sahilmgandhi | 18:6a4db94011d3 | 307 | Those definitions are used by the code which handle the os tick. |
sahilmgandhi | 18:6a4db94011d3 | 308 | To allow compilation of us_ticker programs without RTOS, those symbols are |
sahilmgandhi | 18:6a4db94011d3 | 309 | exported from this module as weak ones. |
sahilmgandhi | 18:6a4db94011d3 | 310 | */ |
sahilmgandhi | 18:6a4db94011d3 | 311 | MBED_WEAK uint32_t const os_trv; |
sahilmgandhi | 18:6a4db94011d3 | 312 | MBED_WEAK uint32_t const os_clockrate; |
sahilmgandhi | 18:6a4db94011d3 | 313 | MBED_WEAK void OS_Tick_Handler(void) |
sahilmgandhi | 18:6a4db94011d3 | 314 | { |
sahilmgandhi | 18:6a4db94011d3 | 315 | } |
sahilmgandhi | 18:6a4db94011d3 | 316 | |
sahilmgandhi | 18:6a4db94011d3 | 317 | |
sahilmgandhi | 18:6a4db94011d3 | 318 | #if defined (__CC_ARM) /* ARMCC Compiler */ |
sahilmgandhi | 18:6a4db94011d3 | 319 | |
sahilmgandhi | 18:6a4db94011d3 | 320 | __asm void COMMON_RTC_IRQ_HANDLER(void) |
sahilmgandhi | 18:6a4db94011d3 | 321 | { |
sahilmgandhi | 18:6a4db94011d3 | 322 | IMPORT OS_Tick_Handler |
sahilmgandhi | 18:6a4db94011d3 | 323 | IMPORT common_rtc_irq_handler |
sahilmgandhi | 18:6a4db94011d3 | 324 | |
sahilmgandhi | 18:6a4db94011d3 | 325 | /** |
sahilmgandhi | 18:6a4db94011d3 | 326 | * Chanel 1 of RTC1 is used by RTX as a systick. |
sahilmgandhi | 18:6a4db94011d3 | 327 | * If the compare event on channel 1 is set, then branch to OS_Tick_Handler. |
sahilmgandhi | 18:6a4db94011d3 | 328 | * Otherwise, just execute common_rtc_irq_handler. |
sahilmgandhi | 18:6a4db94011d3 | 329 | * This function has to be written in assembly and tagged as naked because OS_Tick_Handler |
sahilmgandhi | 18:6a4db94011d3 | 330 | * will never return. |
sahilmgandhi | 18:6a4db94011d3 | 331 | * A c function would put lr on the stack before calling OS_Tick_Handler and this value |
sahilmgandhi | 18:6a4db94011d3 | 332 | * would never been dequeued. |
sahilmgandhi | 18:6a4db94011d3 | 333 | * |
sahilmgandhi | 18:6a4db94011d3 | 334 | * \code |
sahilmgandhi | 18:6a4db94011d3 | 335 | * void COMMON_RTC_IRQ_HANDLER(void) { |
sahilmgandhi | 18:6a4db94011d3 | 336 | if(NRF_RTC1->EVENTS_COMPARE[1]) { |
sahilmgandhi | 18:6a4db94011d3 | 337 | // never return... |
sahilmgandhi | 18:6a4db94011d3 | 338 | OS_Tick_Handler(); |
sahilmgandhi | 18:6a4db94011d3 | 339 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 340 | common_rtc_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 341 | } |
sahilmgandhi | 18:6a4db94011d3 | 342 | } |
sahilmgandhi | 18:6a4db94011d3 | 343 | * \endcode |
sahilmgandhi | 18:6a4db94011d3 | 344 | */ |
sahilmgandhi | 18:6a4db94011d3 | 345 | ldr r0,=0x40011144 |
sahilmgandhi | 18:6a4db94011d3 | 346 | ldr r1, [r0, #0] |
sahilmgandhi | 18:6a4db94011d3 | 347 | cmp r1, #0 |
sahilmgandhi | 18:6a4db94011d3 | 348 | beq US_TICKER_HANDLER |
sahilmgandhi | 18:6a4db94011d3 | 349 | bl OS_Tick_Handler |
sahilmgandhi | 18:6a4db94011d3 | 350 | US_TICKER_HANDLER |
sahilmgandhi | 18:6a4db94011d3 | 351 | push {r3, lr} |
sahilmgandhi | 18:6a4db94011d3 | 352 | bl common_rtc_irq_handler |
sahilmgandhi | 18:6a4db94011d3 | 353 | pop {r3, pc} |
sahilmgandhi | 18:6a4db94011d3 | 354 | ; ALIGN ; |
sahilmgandhi | 18:6a4db94011d3 | 355 | } |
sahilmgandhi | 18:6a4db94011d3 | 356 | |
sahilmgandhi | 18:6a4db94011d3 | 357 | #elif defined (__GNUC__) /* GNU Compiler */ |
sahilmgandhi | 18:6a4db94011d3 | 358 | |
sahilmgandhi | 18:6a4db94011d3 | 359 | __attribute__((naked)) void COMMON_RTC_IRQ_HANDLER(void) |
sahilmgandhi | 18:6a4db94011d3 | 360 | { |
sahilmgandhi | 18:6a4db94011d3 | 361 | /** |
sahilmgandhi | 18:6a4db94011d3 | 362 | * Chanel 1 of RTC1 is used by RTX as a systick. |
sahilmgandhi | 18:6a4db94011d3 | 363 | * If the compare event on channel 1 is set, then branch to OS_Tick_Handler. |
sahilmgandhi | 18:6a4db94011d3 | 364 | * Otherwise, just execute common_rtc_irq_handler. |
sahilmgandhi | 18:6a4db94011d3 | 365 | * This function has to be written in assembly and tagged as naked because OS_Tick_Handler |
sahilmgandhi | 18:6a4db94011d3 | 366 | * will never return. |
sahilmgandhi | 18:6a4db94011d3 | 367 | * A c function would put lr on the stack before calling OS_Tick_Handler and this value |
sahilmgandhi | 18:6a4db94011d3 | 368 | * would never been dequeued. |
sahilmgandhi | 18:6a4db94011d3 | 369 | * |
sahilmgandhi | 18:6a4db94011d3 | 370 | * \code |
sahilmgandhi | 18:6a4db94011d3 | 371 | * void COMMON_RTC_IRQ_HANDLER(void) { |
sahilmgandhi | 18:6a4db94011d3 | 372 | if(NRF_RTC1->EVENTS_COMPARE[1]) { |
sahilmgandhi | 18:6a4db94011d3 | 373 | // never return... |
sahilmgandhi | 18:6a4db94011d3 | 374 | OS_Tick_Handler(); |
sahilmgandhi | 18:6a4db94011d3 | 375 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 376 | common_rtc_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 377 | } |
sahilmgandhi | 18:6a4db94011d3 | 378 | } |
sahilmgandhi | 18:6a4db94011d3 | 379 | * \endcode |
sahilmgandhi | 18:6a4db94011d3 | 380 | */ |
sahilmgandhi | 18:6a4db94011d3 | 381 | __asm__ ( |
sahilmgandhi | 18:6a4db94011d3 | 382 | "ldr r0,=0x40011144\n" |
sahilmgandhi | 18:6a4db94011d3 | 383 | "ldr r1, [r0, #0]\n" |
sahilmgandhi | 18:6a4db94011d3 | 384 | "cmp r1, #0\n" |
sahilmgandhi | 18:6a4db94011d3 | 385 | "beq US_TICKER_HANDLER\n" |
sahilmgandhi | 18:6a4db94011d3 | 386 | "bl OS_Tick_Handler\n" |
sahilmgandhi | 18:6a4db94011d3 | 387 | "US_TICKER_HANDLER:\n" |
sahilmgandhi | 18:6a4db94011d3 | 388 | "push {r3, lr}\n" |
sahilmgandhi | 18:6a4db94011d3 | 389 | "bl common_rtc_irq_handler\n" |
sahilmgandhi | 18:6a4db94011d3 | 390 | "pop {r3, pc}\n" |
sahilmgandhi | 18:6a4db94011d3 | 391 | "nop" |
sahilmgandhi | 18:6a4db94011d3 | 392 | ); |
sahilmgandhi | 18:6a4db94011d3 | 393 | } |
sahilmgandhi | 18:6a4db94011d3 | 394 | |
sahilmgandhi | 18:6a4db94011d3 | 395 | #elif defined (__ICCARM__)//IAR |
sahilmgandhi | 18:6a4db94011d3 | 396 | void common_rtc_irq_handler(void); |
sahilmgandhi | 18:6a4db94011d3 | 397 | |
sahilmgandhi | 18:6a4db94011d3 | 398 | __stackless __task void COMMON_RTC_IRQ_HANDLER(void) |
sahilmgandhi | 18:6a4db94011d3 | 399 | { |
sahilmgandhi | 18:6a4db94011d3 | 400 | uint32_t temp; |
sahilmgandhi | 18:6a4db94011d3 | 401 | |
sahilmgandhi | 18:6a4db94011d3 | 402 | __asm volatile( |
sahilmgandhi | 18:6a4db94011d3 | 403 | " ldr %[temp], [%[reg2check]] \n" |
sahilmgandhi | 18:6a4db94011d3 | 404 | " cmp %[temp], #0 \n" |
sahilmgandhi | 18:6a4db94011d3 | 405 | " beq 1f \n" |
sahilmgandhi | 18:6a4db94011d3 | 406 | " bl.w OS_Tick_Handler \n" |
sahilmgandhi | 18:6a4db94011d3 | 407 | "1: \n" |
sahilmgandhi | 18:6a4db94011d3 | 408 | " push {r3, lr}\n" |
sahilmgandhi | 18:6a4db94011d3 | 409 | " blx %[rtc_irq] \n" |
sahilmgandhi | 18:6a4db94011d3 | 410 | " pop {r3, pc}\n" |
sahilmgandhi | 18:6a4db94011d3 | 411 | |
sahilmgandhi | 18:6a4db94011d3 | 412 | : /* Outputs */ |
sahilmgandhi | 18:6a4db94011d3 | 413 | [temp] "=&r"(temp) |
sahilmgandhi | 18:6a4db94011d3 | 414 | : /* Inputs */ |
sahilmgandhi | 18:6a4db94011d3 | 415 | [reg2check] "r"(0x40011144), |
sahilmgandhi | 18:6a4db94011d3 | 416 | [rtc_irq] "r"(common_rtc_irq_handler) |
sahilmgandhi | 18:6a4db94011d3 | 417 | : /* Clobbers */ |
sahilmgandhi | 18:6a4db94011d3 | 418 | "cc" |
sahilmgandhi | 18:6a4db94011d3 | 419 | ); |
sahilmgandhi | 18:6a4db94011d3 | 420 | (void)temp; |
sahilmgandhi | 18:6a4db94011d3 | 421 | } |
sahilmgandhi | 18:6a4db94011d3 | 422 | |
sahilmgandhi | 18:6a4db94011d3 | 423 | |
sahilmgandhi | 18:6a4db94011d3 | 424 | #else |
sahilmgandhi | 18:6a4db94011d3 | 425 | |
sahilmgandhi | 18:6a4db94011d3 | 426 | #error Compiler not supported. |
sahilmgandhi | 18:6a4db94011d3 | 427 | #error Provide a definition of COMMON_RTC_IRQ_HANDLER. |
sahilmgandhi | 18:6a4db94011d3 | 428 | |
sahilmgandhi | 18:6a4db94011d3 | 429 | /* |
sahilmgandhi | 18:6a4db94011d3 | 430 | * Chanel 1 of RTC1 is used by RTX as a systick. |
sahilmgandhi | 18:6a4db94011d3 | 431 | * If the compare event on channel 1 is set, then branch to OS_Tick_Handler. |
sahilmgandhi | 18:6a4db94011d3 | 432 | * Otherwise, just execute common_rtc_irq_handler. |
sahilmgandhi | 18:6a4db94011d3 | 433 | * This function has to be written in assembly and tagged as naked because OS_Tick_Handler |
sahilmgandhi | 18:6a4db94011d3 | 434 | * will never return. |
sahilmgandhi | 18:6a4db94011d3 | 435 | * A c function would put lr on the stack before calling OS_Tick_Handler and this value |
sahilmgandhi | 18:6a4db94011d3 | 436 | * will never been dequeued. After a certain time a stack overflow will happen. |
sahilmgandhi | 18:6a4db94011d3 | 437 | * |
sahilmgandhi | 18:6a4db94011d3 | 438 | * \code |
sahilmgandhi | 18:6a4db94011d3 | 439 | * void COMMON_RTC_IRQ_HANDLER(void) { |
sahilmgandhi | 18:6a4db94011d3 | 440 | if(NRF_RTC1->EVENTS_COMPARE[1]) { |
sahilmgandhi | 18:6a4db94011d3 | 441 | // never return... |
sahilmgandhi | 18:6a4db94011d3 | 442 | OS_Tick_Handler(); |
sahilmgandhi | 18:6a4db94011d3 | 443 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 444 | common_rtc_irq_handler(); |
sahilmgandhi | 18:6a4db94011d3 | 445 | } |
sahilmgandhi | 18:6a4db94011d3 | 446 | } |
sahilmgandhi | 18:6a4db94011d3 | 447 | * \endcode |
sahilmgandhi | 18:6a4db94011d3 | 448 | */ |
sahilmgandhi | 18:6a4db94011d3 | 449 | |
sahilmgandhi | 18:6a4db94011d3 | 450 | #endif |
sahilmgandhi | 18:6a4db94011d3 | 451 | |
sahilmgandhi | 18:6a4db94011d3 | 452 | /** |
sahilmgandhi | 18:6a4db94011d3 | 453 | * Return the next number of clock cycle needed for the next tick. |
sahilmgandhi | 18:6a4db94011d3 | 454 | * @note This function has been carrefuly optimized for a systick occuring every 1000us. |
sahilmgandhi | 18:6a4db94011d3 | 455 | */ |
sahilmgandhi | 18:6a4db94011d3 | 456 | static uint32_t get_next_tick_cc_delta() |
sahilmgandhi | 18:6a4db94011d3 | 457 | { |
sahilmgandhi | 18:6a4db94011d3 | 458 | uint32_t delta = 0; |
sahilmgandhi | 18:6a4db94011d3 | 459 | |
sahilmgandhi | 18:6a4db94011d3 | 460 | if (os_clockrate != 1000) { |
sahilmgandhi | 18:6a4db94011d3 | 461 | // In RTX, by default SYSTICK is is used. |
sahilmgandhi | 18:6a4db94011d3 | 462 | // A tick event is generated every os_trv + 1 clock cycles of the system timer. |
sahilmgandhi | 18:6a4db94011d3 | 463 | delta = os_trv + 1; |
sahilmgandhi | 18:6a4db94011d3 | 464 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 465 | // If the clockrate is set to 1000us then 1000 tick should happen every second. |
sahilmgandhi | 18:6a4db94011d3 | 466 | // Unfortunatelly, when clockrate is set to 1000, os_trv is equal to 31. |
sahilmgandhi | 18:6a4db94011d3 | 467 | // If (os_trv + 1) is used as the delta value between two ticks, 1000 ticks will be |
sahilmgandhi | 18:6a4db94011d3 | 468 | // generated in 32000 clock cycle instead of 32768 clock cycles. |
sahilmgandhi | 18:6a4db94011d3 | 469 | // As a result, if a user schedule an OS timer to start in 100s, the timer will start |
sahilmgandhi | 18:6a4db94011d3 | 470 | // instead after 97.656s |
sahilmgandhi | 18:6a4db94011d3 | 471 | // The code below fix this issue, a clock rate of 1000s will generate 1000 ticks in 32768 |
sahilmgandhi | 18:6a4db94011d3 | 472 | // clock cycles. |
sahilmgandhi | 18:6a4db94011d3 | 473 | // The strategy is simple, for 1000 ticks: |
sahilmgandhi | 18:6a4db94011d3 | 474 | // * 768 ticks will occur 33 clock cycles after the previous tick |
sahilmgandhi | 18:6a4db94011d3 | 475 | // * 232 ticks will occur 32 clock cycles after the previous tick |
sahilmgandhi | 18:6a4db94011d3 | 476 | // By default every delta is equal to 33. |
sahilmgandhi | 18:6a4db94011d3 | 477 | // Every five ticks (20%, 200 delta in one second), the delta is equal to 32 |
sahilmgandhi | 18:6a4db94011d3 | 478 | // The remaining (32) deltas equal to 32 are distributed using primes numbers. |
sahilmgandhi | 18:6a4db94011d3 | 479 | static uint32_t counter = 0; |
sahilmgandhi | 18:6a4db94011d3 | 480 | if ((counter % 5) == 0 || (counter % 31) == 0 || (counter % 139) == 0 || (counter == 503)) { |
sahilmgandhi | 18:6a4db94011d3 | 481 | delta = 32; |
sahilmgandhi | 18:6a4db94011d3 | 482 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 483 | delta = 33; |
sahilmgandhi | 18:6a4db94011d3 | 484 | } |
sahilmgandhi | 18:6a4db94011d3 | 485 | ++counter; |
sahilmgandhi | 18:6a4db94011d3 | 486 | if (counter == 1000) { |
sahilmgandhi | 18:6a4db94011d3 | 487 | counter = 0; |
sahilmgandhi | 18:6a4db94011d3 | 488 | } |
sahilmgandhi | 18:6a4db94011d3 | 489 | } |
sahilmgandhi | 18:6a4db94011d3 | 490 | return delta; |
sahilmgandhi | 18:6a4db94011d3 | 491 | } |
sahilmgandhi | 18:6a4db94011d3 | 492 | |
sahilmgandhi | 18:6a4db94011d3 | 493 | static inline void clear_tick_interrupt() |
sahilmgandhi | 18:6a4db94011d3 | 494 | { |
sahilmgandhi | 18:6a4db94011d3 | 495 | nrf_rtc_event_clear(COMMON_RTC_INSTANCE, OS_TICK_EVENT); |
sahilmgandhi | 18:6a4db94011d3 | 496 | nrf_rtc_event_disable(COMMON_RTC_INSTANCE, OS_TICK_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 497 | } |
sahilmgandhi | 18:6a4db94011d3 | 498 | |
sahilmgandhi | 18:6a4db94011d3 | 499 | /** |
sahilmgandhi | 18:6a4db94011d3 | 500 | * Indicate if a value is included in a range which can be wrapped. |
sahilmgandhi | 18:6a4db94011d3 | 501 | * @param begin start of the range |
sahilmgandhi | 18:6a4db94011d3 | 502 | * @param end end of the range |
sahilmgandhi | 18:6a4db94011d3 | 503 | * @param val value to check |
sahilmgandhi | 18:6a4db94011d3 | 504 | * @return true if the value is included in the range and false otherwise. |
sahilmgandhi | 18:6a4db94011d3 | 505 | */ |
sahilmgandhi | 18:6a4db94011d3 | 506 | static inline bool is_in_wrapped_range(uint32_t begin, uint32_t end, uint32_t val) |
sahilmgandhi | 18:6a4db94011d3 | 507 | { |
sahilmgandhi | 18:6a4db94011d3 | 508 | // regular case, begin < end |
sahilmgandhi | 18:6a4db94011d3 | 509 | // return true if begin <= val < end |
sahilmgandhi | 18:6a4db94011d3 | 510 | if (begin < end) { |
sahilmgandhi | 18:6a4db94011d3 | 511 | if (begin <= val && val < end) { |
sahilmgandhi | 18:6a4db94011d3 | 512 | return true; |
sahilmgandhi | 18:6a4db94011d3 | 513 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 514 | return false; |
sahilmgandhi | 18:6a4db94011d3 | 515 | } |
sahilmgandhi | 18:6a4db94011d3 | 516 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 517 | // In this case end < begin because it has wrap around the limits |
sahilmgandhi | 18:6a4db94011d3 | 518 | // return false if end < val < begin |
sahilmgandhi | 18:6a4db94011d3 | 519 | if (end < val && val < begin) { |
sahilmgandhi | 18:6a4db94011d3 | 520 | return false; |
sahilmgandhi | 18:6a4db94011d3 | 521 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 522 | return true; |
sahilmgandhi | 18:6a4db94011d3 | 523 | } |
sahilmgandhi | 18:6a4db94011d3 | 524 | } |
sahilmgandhi | 18:6a4db94011d3 | 525 | |
sahilmgandhi | 18:6a4db94011d3 | 526 | } |
sahilmgandhi | 18:6a4db94011d3 | 527 | |
sahilmgandhi | 18:6a4db94011d3 | 528 | /** |
sahilmgandhi | 18:6a4db94011d3 | 529 | * Register the next tick. |
sahilmgandhi | 18:6a4db94011d3 | 530 | */ |
sahilmgandhi | 18:6a4db94011d3 | 531 | static void register_next_tick() |
sahilmgandhi | 18:6a4db94011d3 | 532 | { |
sahilmgandhi | 18:6a4db94011d3 | 533 | previous_tick_cc_value = nrf_rtc_cc_get(COMMON_RTC_INSTANCE, OS_TICK_CC_CHANNEL); |
sahilmgandhi | 18:6a4db94011d3 | 534 | uint32_t delta = get_next_tick_cc_delta(); |
sahilmgandhi | 18:6a4db94011d3 | 535 | uint32_t new_compare_value = (previous_tick_cc_value + delta) & MAX_RTC_COUNTER_VAL; |
sahilmgandhi | 18:6a4db94011d3 | 536 | |
sahilmgandhi | 18:6a4db94011d3 | 537 | // Disable irq directly for few cycles, |
sahilmgandhi | 18:6a4db94011d3 | 538 | // Validation of the new CC value against the COUNTER, |
sahilmgandhi | 18:6a4db94011d3 | 539 | // Setting the new CC value and enabling CC IRQ should be an atomic operation |
sahilmgandhi | 18:6a4db94011d3 | 540 | // Otherwise, there is a possibility to set an invalid CC value because |
sahilmgandhi | 18:6a4db94011d3 | 541 | // the RTC1 keeps running. |
sahilmgandhi | 18:6a4db94011d3 | 542 | // This code is very short 20-38 cycles in the worst case, it shouldn't |
sahilmgandhi | 18:6a4db94011d3 | 543 | // disturb softdevice. |
sahilmgandhi | 18:6a4db94011d3 | 544 | core_util_critical_section_enter(); |
sahilmgandhi | 18:6a4db94011d3 | 545 | uint32_t current_counter = nrf_rtc_counter_get(COMMON_RTC_INSTANCE); |
sahilmgandhi | 18:6a4db94011d3 | 546 | |
sahilmgandhi | 18:6a4db94011d3 | 547 | // If an overflow occur, set the next tick in COUNTER + delta clock cycles |
sahilmgandhi | 18:6a4db94011d3 | 548 | if (is_in_wrapped_range(previous_tick_cc_value, new_compare_value, current_counter + 1) == false) { |
sahilmgandhi | 18:6a4db94011d3 | 549 | new_compare_value = current_counter + delta; |
sahilmgandhi | 18:6a4db94011d3 | 550 | } |
sahilmgandhi | 18:6a4db94011d3 | 551 | nrf_rtc_cc_set(COMMON_RTC_INSTANCE, OS_TICK_CC_CHANNEL, new_compare_value); |
sahilmgandhi | 18:6a4db94011d3 | 552 | // Enable generation of the compare event for the value set above (this |
sahilmgandhi | 18:6a4db94011d3 | 553 | // event will trigger the interrupt). |
sahilmgandhi | 18:6a4db94011d3 | 554 | nrf_rtc_event_enable(COMMON_RTC_INSTANCE, OS_TICK_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 555 | core_util_critical_section_exit(); |
sahilmgandhi | 18:6a4db94011d3 | 556 | } |
sahilmgandhi | 18:6a4db94011d3 | 557 | |
sahilmgandhi | 18:6a4db94011d3 | 558 | /** |
sahilmgandhi | 18:6a4db94011d3 | 559 | * Initialize alternative hardware timer as RTX kernel timer |
sahilmgandhi | 18:6a4db94011d3 | 560 | * This function is directly called by RTX. |
sahilmgandhi | 18:6a4db94011d3 | 561 | * @note this function shouldn't be called directly. |
sahilmgandhi | 18:6a4db94011d3 | 562 | * @return IRQ number of the alternative hardware timer |
sahilmgandhi | 18:6a4db94011d3 | 563 | */ |
sahilmgandhi | 18:6a4db94011d3 | 564 | int os_tick_init (void) |
sahilmgandhi | 18:6a4db94011d3 | 565 | { |
sahilmgandhi | 18:6a4db94011d3 | 566 | common_rtc_init(); |
sahilmgandhi | 18:6a4db94011d3 | 567 | nrf_rtc_int_enable(COMMON_RTC_INSTANCE, OS_TICK_INT_MASK); |
sahilmgandhi | 18:6a4db94011d3 | 568 | |
sahilmgandhi | 18:6a4db94011d3 | 569 | nrf_rtc_cc_set(COMMON_RTC_INSTANCE, OS_TICK_CC_CHANNEL, 0); |
sahilmgandhi | 18:6a4db94011d3 | 570 | register_next_tick(); |
sahilmgandhi | 18:6a4db94011d3 | 571 | |
sahilmgandhi | 18:6a4db94011d3 | 572 | return nrf_drv_get_IRQn(COMMON_RTC_INSTANCE); |
sahilmgandhi | 18:6a4db94011d3 | 573 | } |
sahilmgandhi | 18:6a4db94011d3 | 574 | |
sahilmgandhi | 18:6a4db94011d3 | 575 | /** |
sahilmgandhi | 18:6a4db94011d3 | 576 | * Acknowledge the tick interrupt. |
sahilmgandhi | 18:6a4db94011d3 | 577 | * This function is called by the function OS_Tick_Handler of RTX. |
sahilmgandhi | 18:6a4db94011d3 | 578 | * @note this function shouldn't be called directly. |
sahilmgandhi | 18:6a4db94011d3 | 579 | */ |
sahilmgandhi | 18:6a4db94011d3 | 580 | void os_tick_irqack(void) |
sahilmgandhi | 18:6a4db94011d3 | 581 | { |
sahilmgandhi | 18:6a4db94011d3 | 582 | clear_tick_interrupt(); |
sahilmgandhi | 18:6a4db94011d3 | 583 | register_next_tick(); |
sahilmgandhi | 18:6a4db94011d3 | 584 | } |
sahilmgandhi | 18:6a4db94011d3 | 585 | |
sahilmgandhi | 18:6a4db94011d3 | 586 | /** |
sahilmgandhi | 18:6a4db94011d3 | 587 | * Returns the overflow flag of the alternative hardware timer. |
sahilmgandhi | 18:6a4db94011d3 | 588 | * @note This function is exposed by RTX kernel. |
sahilmgandhi | 18:6a4db94011d3 | 589 | * @return 1 if the timer has overflowed and 0 otherwise. |
sahilmgandhi | 18:6a4db94011d3 | 590 | */ |
sahilmgandhi | 18:6a4db94011d3 | 591 | uint32_t os_tick_ovf(void) |
sahilmgandhi | 18:6a4db94011d3 | 592 | { |
sahilmgandhi | 18:6a4db94011d3 | 593 | uint32_t current_counter = nrf_rtc_counter_get(COMMON_RTC_INSTANCE); |
sahilmgandhi | 18:6a4db94011d3 | 594 | uint32_t next_tick_cc_value = nrf_rtc_cc_get(COMMON_RTC_INSTANCE, OS_TICK_CC_CHANNEL); |
sahilmgandhi | 18:6a4db94011d3 | 595 | |
sahilmgandhi | 18:6a4db94011d3 | 596 | return is_in_wrapped_range(previous_tick_cc_value, next_tick_cc_value, current_counter) ? 0 : 1; |
sahilmgandhi | 18:6a4db94011d3 | 597 | } |
sahilmgandhi | 18:6a4db94011d3 | 598 | |
sahilmgandhi | 18:6a4db94011d3 | 599 | /** |
sahilmgandhi | 18:6a4db94011d3 | 600 | * Return the value of the alternative hardware timer. |
sahilmgandhi | 18:6a4db94011d3 | 601 | * @note The documentation is not very clear about what is expected as a result, |
sahilmgandhi | 18:6a4db94011d3 | 602 | * is it an ascending counter, a descending one ? |
sahilmgandhi | 18:6a4db94011d3 | 603 | * None of this is specified. |
sahilmgandhi | 18:6a4db94011d3 | 604 | * The default systick is a descending counter and this function return values in |
sahilmgandhi | 18:6a4db94011d3 | 605 | * descending order, even if the internal counter used is an ascending one. |
sahilmgandhi | 18:6a4db94011d3 | 606 | * @return the value of the alternative hardware timer. |
sahilmgandhi | 18:6a4db94011d3 | 607 | */ |
sahilmgandhi | 18:6a4db94011d3 | 608 | uint32_t os_tick_val(void) |
sahilmgandhi | 18:6a4db94011d3 | 609 | { |
sahilmgandhi | 18:6a4db94011d3 | 610 | uint32_t current_counter = nrf_rtc_counter_get(COMMON_RTC_INSTANCE); |
sahilmgandhi | 18:6a4db94011d3 | 611 | uint32_t next_tick_cc_value = nrf_rtc_cc_get(COMMON_RTC_INSTANCE, OS_TICK_CC_CHANNEL); |
sahilmgandhi | 18:6a4db94011d3 | 612 | |
sahilmgandhi | 18:6a4db94011d3 | 613 | // do not use os_tick_ovf because its counter value can be different |
sahilmgandhi | 18:6a4db94011d3 | 614 | if(is_in_wrapped_range(previous_tick_cc_value, next_tick_cc_value, current_counter)) { |
sahilmgandhi | 18:6a4db94011d3 | 615 | if (next_tick_cc_value > previous_tick_cc_value) { |
sahilmgandhi | 18:6a4db94011d3 | 616 | return next_tick_cc_value - current_counter; |
sahilmgandhi | 18:6a4db94011d3 | 617 | } else if(current_counter <= next_tick_cc_value) { |
sahilmgandhi | 18:6a4db94011d3 | 618 | return next_tick_cc_value - current_counter; |
sahilmgandhi | 18:6a4db94011d3 | 619 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 620 | return next_tick_cc_value + (MAX_RTC_COUNTER_VAL - current_counter); |
sahilmgandhi | 18:6a4db94011d3 | 621 | } |
sahilmgandhi | 18:6a4db94011d3 | 622 | } else { |
sahilmgandhi | 18:6a4db94011d3 | 623 | // use (os_trv + 1) has the base step, can be totally inacurate ... |
sahilmgandhi | 18:6a4db94011d3 | 624 | uint32_t clock_cycles_by_tick = os_trv + 1; |
sahilmgandhi | 18:6a4db94011d3 | 625 | |
sahilmgandhi | 18:6a4db94011d3 | 626 | // if current counter has wrap arround, add the limit to it. |
sahilmgandhi | 18:6a4db94011d3 | 627 | if (current_counter < next_tick_cc_value) { |
sahilmgandhi | 18:6a4db94011d3 | 628 | current_counter = current_counter + MAX_RTC_COUNTER_VAL; |
sahilmgandhi | 18:6a4db94011d3 | 629 | } |
sahilmgandhi | 18:6a4db94011d3 | 630 | |
sahilmgandhi | 18:6a4db94011d3 | 631 | return clock_cycles_by_tick - ((current_counter - next_tick_cc_value) % clock_cycles_by_tick); |
sahilmgandhi | 18:6a4db94011d3 | 632 | } |
sahilmgandhi | 18:6a4db94011d3 | 633 | |
sahilmgandhi | 18:6a4db94011d3 | 634 | } |
sahilmgandhi | 18:6a4db94011d3 | 635 | |
sahilmgandhi | 18:6a4db94011d3 | 636 | #endif // defined(TARGET_MCU_NRF51822) |