1 /* 2 * SPDX-FileCopyrightText: 2017-2021 Espressif Systems (Shanghai) CO LTD 3 * 4 * SPDX-License-Identifier: Apache-2.0 5 */ 6 7 #pragma once 8 9 /** 10 * @file private_include/esp_timer_impl.h 11 * 12 * @brief Interface between common and platform-specific parts of esp_timer. 13 * 14 * The functions in this header file are implemented for each supported SoC. 15 * High level functions defined in esp_timer.c call the functions here to 16 * interact with the hardware. 17 */ 18 19 #include <stdint.h> 20 #include "esp_err.h" 21 22 #ifndef __ZEPHYR__ 23 #include "esp_intr_alloc.h" 24 #else 25 typedef void (*intr_handler_t)(void *arg); 26 #endif 27 28 /** 29 * @brief Minimal initialization of platform specific layer of esp_timer 30 * This function can be called very early in startup process, after this call 31 * only esp_timer_get_time function can be used. 32 * esp_timer_impl_init has to be called after this function to initialize the 33 * rest of esp_timer implementation. 34 * @return ESP_OK 35 */ 36 esp_err_t esp_timer_impl_early_init(void); 37 38 /** 39 * @brief Initialize platform specific layer of esp_timer 40 * @param alarm_handler function to call on timer interrupt 41 * Before calling this function, esp_timer_impl_early_init must be called. 42 * @return ESP_OK, ESP_ERR_NO_MEM, or one of the errors from interrupt allocator 43 */ 44 esp_err_t esp_timer_impl_init(intr_handler_t alarm_handler); 45 46 /** 47 * @brief Deinitialize platform specific layer of esp_timer 48 */ 49 void esp_timer_impl_deinit(void); 50 51 /** 52 * @brief Set up the timer interrupt to fire at a particular time 53 * 54 * If the alarm time is too close in the future, implementation should set the 55 * alarm to the earliest time possible. 56 * 57 * @param timestamp time in microseconds when interrupt should fire (relative to 58 * boot time, i.e. as returned by esp_timer_impl_get_time) 59 */ 60 void esp_timer_impl_set_alarm(uint64_t timestamp); 61 62 /** 63 * @brief Set up the timer interrupt to fire at a particular time for a particular alarm module. 64 * 65 * If the alarm time is too close in the future, implementation should set the 66 * alarm to the earliest time possible. 67 * 68 * @param timestamp time in microseconds when interrupt should fire (relative to 69 * boot time, i.e. as returned by esp_timer_impl_get_time) 70 * 71 * @param alarm_id Id alarm: 72 * 0 - alarm_0 for the ESP_TIMER_TASK dispatch method, 73 * 1 - alarm_1 for the ESP_TIMER_ISR dispatch method. 74 */ 75 void esp_timer_impl_set_alarm_id(uint64_t timestamp, unsigned alarm_id); 76 77 /** 78 * @brief Notify esp_timer implementation that APB frequency has changed 79 * 80 * Called by the frequency switching code. 81 * 82 * @param apb_ticks_per_us new number of APB clock ticks per microsecond 83 */ 84 void esp_timer_impl_update_apb_freq(uint32_t apb_ticks_per_us); 85 86 /** 87 * @brief Adjust current esp_timer time by a certain value 88 * 89 * Called from light sleep code to synchronize esp_timer time with RTC time. 90 * 91 * @param time_us adjustment to apply to esp_timer time, in microseconds 92 */ 93 void esp_timer_impl_advance(int64_t time_us); 94 95 /** 96 * @brief Get time, in microseconds, since esp_timer_impl_init was called 97 * @return timestamp in microseconds 98 */ 99 int64_t esp_timer_impl_get_time(void); 100 101 /** 102 * @brief Get minimal timer period, in microseconds 103 * Periods shorter than the one returned may not be possible to achieve due to 104 * interrupt latency and context switch time. Short period of periodic timer may 105 * cause the system to spend all the time servicing the interrupt and timer 106 * callback, preventing other tasks from running. 107 * @return minimal period of periodic timer, in microseconds 108 */ 109 uint64_t esp_timer_impl_get_min_period_us(void); 110 111 /** 112 * @brief obtain internal critical section used esp_timer implementation 113 * This can be used when a sequence of calls to esp_timer has to be made, 114 * and it is necessary that the state of the timer is consistent between 115 * the calls. Should be treated in the same way as a spinlock. 116 * Call esp_timer_impl_unlock to release the lock 117 */ 118 void esp_timer_impl_lock(void); 119 120 121 /** 122 * @brief counterpart of esp_timer_impl_lock 123 */ 124 void esp_timer_impl_unlock(void); 125 126 /** 127 * @brief Get counting register 128 * 129 * Bit depth dependents on implementation and can be 32-bit or 64-bit. 130 * 131 * @return the value of the counting register 132 */ 133 uint64_t esp_timer_impl_get_counter_reg(void); 134 135 /** 136 * @brief Get alarm register 137 * 138 * Bit depth dependents on implementation and can be 32-bit or 64-bit. 139 * 140 * @return the value of the alarm register 141 */ 142 uint64_t esp_timer_impl_get_alarm_reg(void); 143 144 #if CONFIG_ESP_TIME_FUNCS_USE_ESP_TIMER 145 /** 146 * @brief Initialize esp_timer as system time provider. 147 */ 148 void esp_timer_impl_init_system_time(void); 149 #endif 150
