text: #include <stdio.h>
  #include <stdlib.h>
  #include <time.h>
  #include <sys/time.h>
  #include <sys/param.h>
  #include "esp_timer.h"
  #include "esp_timer_impl.h"
  #include "unity.h"
  #include "soc/frc_timer_reg.h"
  #include "soc/timer_group_reg.h"
  #include "esp_heap_caps.h"
  #include "freertos/FreeRTOS.h"
  #include "freertos/task.h"
  #include "freertos/semphr.h"
  #include "test_utils.h"
  #include "esp_freertos_hooks.h"
  
  #ifdef CONFIG_ESP_TIMER_PROFILING
  #define WITH_PROFILING 1
  #endif
  
  #ifdef CONFIG_ESP_TIMER_IMPL_FRC2
  extern uint32_t esp_timer_impl_get_overflow_val(void);
  extern void esp_timer_impl_set_overflow_val(uint32_t overflow_val);
  
  static uint32_t s_old_overflow_val;
  
  static void setup_overflow(void)
  {
      s_old_overflow_val = esp_timer_impl_get_overflow_val();
      /* Overflow every 0.1 sec.
       * Chosen so that it is 0 modulo s_timer_ticks_per_us (which is 80),
       * to prevent roundoff error on each overflow.
       */
      esp_timer_impl_set_overflow_val(8000000);
  }
  
  static void teardown_overflow(void)
  {
      esp_timer_impl_set_overflow_val(s_old_overflow_val);
  }
  #else
  
  static void setup_overflow(void)
  {
  }
  
  static void teardown_overflow(void)
  {
  }
  
  #endif // CONFIG_ESP_TIMER_IMPL_FRC2
  
  TEST_CASE("esp_timer orders timers correctly", "[esp_timer]")
  {
      void dummy_cb(void* arg)
      {
      }
  
      uint64_t timeouts[] = { 10000, 1000, 10000, 5000, 20000, 1000 };
      size_t indices[] = { 3, 0, 4, 2, 5, 1 };
      const size_t num_timers = sizeof(timeouts)/sizeof(timeouts[0]);
      esp_timer_handle_t handles[num_timers];
      char* names[num_timers];
      setup_overflow();
      for (size_t i = 0; i < num_timers; ++i) {
          asprintf(&names[i], "timer%d", i);
          esp_timer_create_args_t args = {
                  .callback = &dummy_cb,
                  .name = names[i]
          };
          TEST_ESP_OK(esp_timer_create(&args, &handles[i]));
          TEST_ESP_OK(esp_timer_start_once(handles[i], timeouts[i] * 100));
      }
      teardown_overflow();
      char* stream_str[1024];
      FILE* stream = fmemopen(stream_str, sizeof(stream_str), "r+");
      TEST_ESP_OK(esp_timer_dump(stream));
      for (size_t i = 0; i < num_timers; ++i) {
          TEST_ESP_OK(esp_timer_stop(handles[i]));
          TEST_ESP_OK(esp_timer_delete(handles[i]));
          free(names[i]);
      }
      fflush(stream);
      fseek(stream, 0, SEEK_SET);
      for (size_t i = 0; i < num_timers; ++i) {
          char line[128];
          TEST_ASSERT_NOT_NULL(fgets(line, sizeof(line), stream));
  #if WITH_PROFILING
          int timer_id;
          sscanf(line, "timer%d", &timer_id);
          TEST_ASSERT_EQUAL(indices[timer_id], i);
  #else
          intptr_t timer_ptr;
          sscanf(line, "timer@0x%x", &timer_ptr);
          for (size_t j = 0; j < num_timers; ++j) {
              if (indices[j] == i) {
                  TEST_ASSERT_EQUAL_PTR(handles[j], timer_ptr);
                  break;
              }
          }
  #endif
  
      }
      fclose(stream);
  }
  
  TEST_CASE("esp_timer_impl_set_alarm stress test", "[esp_timer]")
  {
      const int test_time_sec = 10;
  
      void set_alarm_task(void* arg)
      {
          SemaphoreHandle_t done = (SemaphoreHandle_t) arg;
  
          uint64_t start = esp_timer_impl_get_time();
          uint64_t now = start;
          int count = 0;
          const int delays[] = {50, 5000, 10000000};
          const int delays_count = sizeof(delays)/sizeof(delays[0]);
          while (now - start < test_time_sec * 1000000) {
              now = esp_timer_impl_get_time();
              esp_timer_impl_set_alarm(now + delays[count % delays_count]);
              ++count;
          }
          xSemaphoreGive(done);
          vTaskDelete(NULL);
      }
  
      SemaphoreHandle_t done = xSemaphoreCreateCounting(portNUM_PROCESSORS, 0);
      setup_overflow();
      xTaskCreatePinnedToCore(&set_alarm_task, "set_alarm_0", 4096, done, UNITY_FREERTOS_PRIORITY, NULL, 0);
  #if portNUM_PROCESSORS == 2
      xTaskCreatePinnedToCore(&set_alarm_task, "set_alarm_1", 4096, done, UNITY_FREERTOS_PRIORITY, NULL, 1);
  #endif
  
      TEST_ASSERT(xSemaphoreTake(done, test_time_sec * 2 * 1000 / portTICK_PERIOD_MS));
  #if portNUM_PROCESSORS == 2
      TEST_ASSERT(xSemaphoreTake(done, test_time_sec * 2 * 1000 / portTICK_PERIOD_MS));
  #endif
      teardown_overflow();
      vSemaphoreDelete(done);
  }
  
  TEST_CASE("esp_timer produces correct delay", "[esp_timer]")
  {
      void timer_func(void* arg)
      {
          int64_t* p_end = (int64_t*) arg;
          *p_end = ref_clock_get();
      }
  
      int64_t t_end;
      esp_timer_handle_t timer1;
      esp_timer_create_args_t args = {
              .callback = &timer_func,
              .arg = &t_end,
              .name = "timer1"
      };
      TEST_ESP_OK(esp_timer_create(&args, &timer1));
  
      const int delays_ms[] = {20, 100, 200, 250};
      const size_t delays_count = sizeof(delays_ms)/sizeof(delays_ms[0]);
  
      ref_clock_init();
      setup_overflow();
      for (size_t i = 0; i < delays_count; ++i) {
          t_end = 0;
          int64_t t_start = ref_clock_get();
  
          TEST_ESP_OK(esp_timer_start_once(timer1, delays_ms[i] * 1000));
  
          vTaskDelay(delays_ms[i] * 2 / portTICK_PERIOD_MS);
          TEST_ASSERT(t_end != 0);
          int32_t ms_diff = (t_end - t_start) / 1000;
          printf("%d %d\n", delays_ms[i], ms_diff);
  
          TEST_ASSERT_INT32_WITHIN(portTICK_PERIOD_MS, delays_ms[i], ms_diff);
      }
      teardown_overflow();
      ref_clock_deinit();
  
      TEST_ESP_OK( esp_timer_dump(stdout) );
  
      esp_timer_delete(timer1);
  }
  
  TEST_CASE("periodic esp_timer produces correct delays", "[esp_timer]")
  {
      // no, we can't make this a const size_t (§6.7.5.2)
  #define NUM_INTERVALS 16
  
      typedef struct {
          esp_timer_handle_t timer;
          size_t cur_interval;
          int intervals[NUM_INTERVALS];
          int64_t t_start;
          SemaphoreHandle_t done;
      } test_args_t;
  
      void timer_func(void* arg)
      {
          test_args_t* p_args = (test_args_t*) arg;
          int64_t t_end = ref_clock_get();
          int32_t ms_diff = (t_end - p_args->t_start) / 1000;
          printf("timer #%d %dms\n", p_args->cur_interval, ms_diff);
          p_args->intervals[p_args->cur_interval++] = ms_diff;
          // Deliberately make timer handler run longer.
          // We check that this doesn't affect the result.
          ets_delay_us(10*1000);
          if (p_args->cur_interval == NUM_INTERVALS) {
              printf("done\n");
              TEST_ESP_OK(esp_timer_stop(p_args->timer));
              xSemaphoreGive(p_args->done);
          }
      }
  
      const int delay_ms = 100;
      test_args_t args = {0};
      esp_timer_handle_t timer1;
      esp_timer_create_args_t create_args = {
              .callback = &timer_func,
              .arg = &args,
              .name = "timer1",
      };
      TEST_ESP_OK(esp_timer_create(&create_args, &timer1));
      ref_clock_init();
      setup_overflow();
      args.timer = timer1;
      args.t_start = ref_clock_get();
      args.done = xSemaphoreCreateBinary();
      TEST_ESP_OK(esp_timer_start_periodic(timer1, delay_ms * 1000));
  
      TEST_ASSERT(xSemaphoreTake(args.done, delay_ms * NUM_INTERVALS * 2));
  
      TEST_ASSERT_EQUAL_UINT32(NUM_INTERVALS, args.cur_interval);
      for (size_t i = 0; i < NUM_INTERVALS; ++i) {
          TEST_ASSERT_INT32_WITHIN(portTICK_PERIOD_MS, (i + 1) * delay_ms, args.intervals[i]);
      }
      teardown_overflow();
      ref_clock_deinit();
      TEST_ESP_OK( esp_timer_dump(stdout) );
  
      TEST_ESP_OK( esp_timer_delete(timer1) );
      vSemaphoreDelete(args.done);
  #undef NUM_INTERVALS
  }
  
  TEST_CASE("multiple timers are ordered correctly", "[esp_timer]")
  {
  #define N 5
  
      typedef struct {
          const int order[N * 3];
          size_t count;
      } test_common_t;
  
      typedef struct {
          int timer_index;
          const int intervals[N];
          size_t intervals_count;
          esp_timer_handle_t timer;
          test_common_t* common;
          bool pass;
          SemaphoreHandle_t done;
          int64_t t_start;
      } test_args_t;
  
      void timer_func(void* arg)
      {
          test_args_t* p_args = (test_args_t*) arg;
          // check order
          size_t count = p_args->common->count;
          int expected_index = p_args->common->order[count];
          int ms_since_start = (ref_clock_get() - p_args->t_start) / 1000;
          printf("Time %dms, at count %d, expected timer %d, got timer %d\n",
                  ms_since_start, count, expected_index, p_args->timer_index);
          if (expected_index != p_args->timer_index) {
              p_args->pass = false;
              esp_timer_stop(p_args->timer);
              xSemaphoreGive(p_args->done);
              return;
          }
          p_args->common->count++;
          if (++p_args->intervals_count == N) {
              esp_timer_stop(p_args->timer);
              xSemaphoreGive(p_args->done);
              return;
          }
          int next_interval = p_args->intervals[p_args->intervals_count];
          printf("starting timer %d interval #%d, %d ms\n",
                  p_args->timer_index, p_args->intervals_count, next_interval);
          esp_timer_start_once(p_args->timer, next_interval * 1000);
      }
  
  
      test_common_t common = {
          .order = {1, 2, 3, 2, 1, 3, 1, 2, 1, 3, 2, 1, 3, 3, 2},
          .count = 0
      };
  
      SemaphoreHandle_t done = xSemaphoreCreateCounting(3, 0);
  
      ref_clock_init();
      int64_t now = ref_clock_get();
  
      test_args_t args1 = {
              .timer_index = 1,
              .intervals = {10, 40, 20, 40, 30},
              .common = &common,
              .pass = true,
              .done = done,
              .t_start = now
      };
  
      test_args_t args2 = {
              .timer_index = 2,
              .intervals = {20, 20, 60, 30, 40},
              .common = &common,
              .pass = true,
              .done = done,
              .t_start = now
      };
  
      test_args_t args3 = {
              .timer_index = 3,
              .intervals = {30, 30, 60, 30, 10},
              .common = &common,
              .pass = true,
              .done = done,
              .t_start = now
      };
  
  
      esp_timer_create_args_t create_args = {
              .callback = &timer_func,
              .arg = &args1,
              .name = "1"
      };
      TEST_ESP_OK(esp_timer_create(&create_args, &args1.timer));
  
      create_args.name = "2";
      create_args.arg = &args2;
      TEST_ESP_OK(esp_timer_create(&create_args, &args2.timer));
  
      create_args.name = "3";
      create_args.arg = &args3;
      TEST_ESP_OK(esp_timer_create(&create_args, &args3.timer));
  
      esp_timer_start_once(args1.timer, args1.intervals[0] * 1000);
      esp_timer_start_once(args2.timer, args2.intervals[0] * 1000);
      esp_timer_start_once(args3.timer, args3.intervals[0] * 1000);
  
      for (int i = 0; i < 3; ++i) {
          int result = xSemaphoreTake(done, 1000 / portTICK_PERIOD_MS);
          TEST_ASSERT_TRUE(result == pdPASS);
      }
  
      TEST_ASSERT_TRUE(args1.pass);
      TEST_ASSERT_TRUE(args2.pass);
      TEST_ASSERT_TRUE(args3.pass);
  
      ref_clock_deinit();
  
      TEST_ESP_OK( esp_timer_dump(stdout) );
  
      TEST_ESP_OK( esp_timer_delete(args1.timer) );
      TEST_ESP_OK( esp_timer_delete(args2.timer) );
      TEST_ESP_OK( esp_timer_delete(args3.timer) );
  
  #undef N
  }
  
  /* Create two timers, start them around the same time, and search through
   * timeout delta values to reproduce the case when timeouts occur close to
   * each other, testing the "multiple timers triggered" code path in timer_process_alarm.
   */
  TEST_CASE("esp_timer for very short intervals", "[esp_timer]")
  {
      SemaphoreHandle_t semaphore = xSemaphoreCreateCounting(2, 0);
  
      void timer_func(void* arg) {
          SemaphoreHandle_t done = (SemaphoreHandle_t) arg;
          xSemaphoreGive(done);
          printf(".");
      }
  
      esp_timer_create_args_t timer_args = {
              .callback = &timer_func,
              .arg = (void*) semaphore,
              .name = "foo"
      };
  
      esp_timer_handle_t timer1, timer2;
      ESP_ERROR_CHECK( esp_timer_create(&timer_args, &timer1) );
      ESP_ERROR_CHECK( esp_timer_create(&timer_args, &timer2) );
      setup_overflow();
      const int timeout_ms = 10;
      for (int timeout_delta_us = -150; timeout_delta_us < 150; timeout_delta_us++) {
          printf("delta=%d", timeout_delta_us);
          ESP_ERROR_CHECK( esp_timer_start_once(timer1, timeout_ms * 1000) );
          ESP_ERROR_CHECK( esp_timer_start_once(timer2, timeout_ms * 1000 + timeout_delta_us) );
          TEST_ASSERT_EQUAL(pdPASS, xSemaphoreTake(semaphore, timeout_ms * 2));
          TEST_ASSERT_EQUAL(pdPASS, xSemaphoreTake(semaphore, timeout_ms * 2));
          printf("\n");
          TEST_ESP_ERR(ESP_ERR_INVALID_STATE, esp_timer_stop(timer1));
          TEST_ESP_ERR(ESP_ERR_INVALID_STATE, esp_timer_stop(timer2));
      }
  
      teardown_overflow();
      vSemaphoreDelete(semaphore);
  }
  
  
  TEST_CASE("esp_timer_get_time call takes less than 1us", "[esp_timer]")
  {
      int64_t begin = esp_timer_get_time();
      volatile int64_t end;
      const int iter_count = 10000;
      for (int i = 0; i < iter_count; ++i) {
          end = esp_timer_get_time();
      }
      int ns_per_call = (int) ((end - begin) * 1000 / iter_count);
      TEST_PERFORMANCE_LESS_THAN(ESP_TIMER_GET_TIME_PER_CALL, "%dns", ns_per_call);
  }
  
  static int64_t IRAM_ATTR __attribute__((noinline)) get_clock_diff(void)
  {
      uint64_t hs_time = esp_timer_get_time();
      uint64_t ref_time = ref_clock_get();
      return hs_time - ref_time;
  }
  
  TEST_CASE("esp_timer_get_time returns monotonic values", "[esp_timer]")
  {
      typedef struct {
          SemaphoreHandle_t done;
          bool pass;
          int test_cnt;
          int error_cnt;
          int64_t max_error;
          int64_t avg_diff;
          int64_t dummy;
      } test_state_t;
  
      void timer_test_task(void* arg) {
          test_state_t* state = (test_state_t*) arg;
          state->pass = true;
  
          /* make sure both functions are in cache */
          state->dummy = get_clock_diff();
  
          /* calculate the difference between the two clocks */
          portDISABLE_INTERRUPTS();
          int64_t delta = get_clock_diff();
          portENABLE_INTERRUPTS();
          int64_t start_time = ref_clock_get();
          int error_repeat_cnt = 0;
          while (ref_clock_get() - start_time < 10000000) {  /* 10 seconds */
              /* Get values of both clocks again, and check that they are close to 'delta'.
               * We don't disable interrupts here, because esp_timer_get_time doesn't lock
               * interrupts internally, so we check if it can get "broken" by a well placed
               * interrupt.
               */
              int64_t diff = get_clock_diff() - delta;
              /* Allow some difference due to rtos tick interrupting task between
               * getting 'hs_now' and 'now'.
               */
              if (abs(diff) > 100) {
                  error_repeat_cnt++;
                  state->error_cnt++;
              } else {
                  error_repeat_cnt = 0;
              }
              if (error_repeat_cnt > 2) {
                  printf("diff=%lld\n", diff);
                  state->pass = false;
              }
              state->avg_diff += diff;
              state->max_error = MAX(state->max_error, abs(diff));
              state->test_cnt++;
          }
          state->avg_diff /= state->test_cnt;
          xSemaphoreGive(state->done);
          vTaskDelete(NULL);
      }
  
      ref_clock_init();
      setup_overflow();
  
      test_state_t states[portNUM_PROCESSORS] = {0};
      SemaphoreHandle_t done = xSemaphoreCreateCounting(portNUM_PROCESSORS, 0);
      for (int i = 0; i < portNUM_PROCESSORS; ++i) {
          states[i].done = done;
          xTaskCreatePinnedToCore(&timer_test_task, "test", 4096, &states[i], 6, NULL, i);
      }
  
      for (int i = 0; i < portNUM_PROCESSORS; ++i) {
          TEST_ASSERT_TRUE( xSemaphoreTake(done, portMAX_DELAY) );
          printf("CPU%d: %s test_cnt=%d error_cnt=%d avg_diff=%d |max_error|=%d\n",
                  i, states[i].pass ? "PASS" : "FAIL",
                  states[i].test_cnt, states[i].error_cnt,
                  (int) states[i].avg_diff, (int) states[i].max_error);
      }
  
      vSemaphoreDelete(done);
      teardown_overflow();
      ref_clock_deinit();
  
      for (int i = 0; i < portNUM_PROCESSORS; ++i) {
          TEST_ASSERT(states[i].pass);
      }
  }
  
  TEST_CASE("Can dump esp_timer stats", "[esp_timer]")
  {
      esp_timer_dump(stdout);
  }
  
  TEST_CASE("Can delete timer from callback", "[esp_timer]")
  {
      typedef struct {
          SemaphoreHandle_t notify_from_timer_cb;
          esp_timer_handle_t timer;
      } test_arg_t;
  
      void timer_func(void* varg)
      {
          test_arg_t arg = *(test_arg_t*) varg;
          esp_timer_delete(arg.timer);
          printf("Timer %p is deleted\n", arg.timer);
          xSemaphoreGive(arg.notify_from_timer_cb);
      }
  
      test_arg_t args = {
              .notify_from_timer_cb = xSemaphoreCreateBinary(),
      };
  
      esp_timer_create_args_t timer_args = {
              .callback = &timer_func,
              .arg = &args,
              .name = "self_deleter"
      };
      esp_timer_create(&timer_args, &args.timer);
      esp_timer_start_once(args.timer, 10000);
  
      TEST_ASSERT_TRUE(xSemaphoreTake(args.notify_from_timer_cb, 1000 / portTICK_PERIOD_MS));
      printf("Checking heap at %p\n", args.timer);
      TEST_ASSERT_TRUE(heap_caps_check_integrity_addr((intptr_t) args.timer, true));
  
      vSemaphoreDelete(args.notify_from_timer_cb);
  }
  
  
  typedef struct {
      SemaphoreHandle_t delete_start;
      SemaphoreHandle_t delete_done;
      SemaphoreHandle_t test_done;
      esp_timer_handle_t timer;
  } timer_delete_test_args_t;
  
  static void timer_delete_task(void* arg)
  {
      timer_delete_test_args_t* args = (timer_delete_test_args_t*) arg;
      xSemaphoreTake(args->delete_start, portMAX_DELAY);
      printf("Deleting the timer\n");
      esp_timer_delete(args->timer);
      printf("Timer deleted\n");
      xSemaphoreGive(args->delete_done);
      vTaskDelete(NULL);
  }
  
  static void timer_delete_test_callback(void* arg)
  {
      timer_delete_test_args_t* args = (timer_delete_test_args_t*) arg;
      printf("Timer callback called\n");
      xSemaphoreGive(args->delete_start);
      xSemaphoreTake(args->delete_done, portMAX_DELAY);
      printf("Callback complete\n");
      xSemaphoreGive(args->test_done);
  }
  
  TEST_CASE("Can delete timer from a separate task, triggered from callback", "[esp_timer]")
  {
      timer_delete_test_args_t args = {
          .delete_start = xSemaphoreCreateBinary(),
          .delete_done = xSemaphoreCreateBinary(),
          .test_done = xSemaphoreCreateBinary(),
      };
  
      esp_timer_create_args_t timer_args = {
              .callback = &timer_delete_test_callback,
              .arg = &args
      };
      esp_timer_handle_t timer;
      TEST_ESP_OK(esp_timer_create(&timer_args, &timer));
      args.timer = timer;
  
      xTaskCreate(timer_delete_task, "deleter", 4096, &args, 5, NULL);
  
      esp_timer_start_once(timer, 100);
      TEST_ASSERT(xSemaphoreTake(args.test_done, pdMS_TO_TICKS(1000)));
  
      vSemaphoreDelete(args.delete_done);
      vSemaphoreDelete(args.delete_start);
      vSemaphoreDelete(args.test_done);
  }
  
  TEST_CASE("esp_timer_impl_advance moves time base correctly", "[esp_timer]")
  {
      int64_t t0 = esp_timer_get_time();
      const int64_t diff_us = 1000000;
      esp_timer_impl_advance(diff_us);
      int64_t t1 = esp_timer_get_time();
      int64_t t_delta = t1 - t0;
      printf("diff_us=%lld t0=%lld t1=%lld t1-t0=%lld\n", diff_us, t0, t1, t_delta);
      TEST_ASSERT_INT_WITHIN(1000, diff_us, (int) t_delta);
  }
  
  
  TEST_CASE("after esp_timer_impl_advance, timers run when expected", "[esp_timer]")
  {
      typedef struct {
          int64_t cb_time;
      } test_state_t;
  
      void timer_func(void* varg) {
          test_state_t* arg = (test_state_t*) varg;
          arg->cb_time = ref_clock_get();
      }
  
      ref_clock_init();
  
      test_state_t state = { 0 };
  
      esp_timer_create_args_t timer_args = {
              .callback = &timer_func,
              .arg = &state
      };
      esp_timer_handle_t timer;
      TEST_ESP_OK(esp_timer_create(&timer_args, &timer));
  
      const int64_t interval = 10000;
      const int64_t advance = 2000;
  
      printf("test 1\n");
      int64_t t_start = ref_clock_get();
      esp_timer_start_once(timer, interval);
      esp_timer_impl_advance(advance);
      vTaskDelay(2 * interval / 1000 / portTICK_PERIOD_MS);
  
      TEST_ASSERT_INT_WITHIN(portTICK_PERIOD_MS * 1000, interval - advance, state.cb_time - t_start);
  
      printf("test 2\n");
      state.cb_time = 0;
      t_start = ref_clock_get();
      esp_timer_start_once(timer, interval);
      esp_timer_impl_advance(interval);
      vTaskDelay(1);
  
      TEST_ASSERT(state.cb_time > t_start);
  
      ref_clock_deinit();
  }
  
  static esp_timer_handle_t timer1;
  static SemaphoreHandle_t sem;
  static void IRAM_ATTR test_tick_hook(void)
  {
      static int i;
      const int iterations = 16;
  
      if (++i <= iterations) {
          if (i & 0x1) {
              TEST_ESP_OK(esp_timer_start_once(timer1, 5000));
          } else {
              TEST_ESP_OK(esp_timer_stop(timer1));
          }
      } else {
          xSemaphoreGiveFromISR(sem, 0);
      }
  }
  
  TEST_CASE("Can start/stop timer from ISR context", "[esp_timer]")
  {
      void timer_func(void* arg)
      {
          printf("timer cb\n");
      }
  
      esp_timer_create_args_t create_args = {
          .callback = &timer_func,
      };
      TEST_ESP_OK(esp_timer_create(&create_args, &timer1));
      sem = xSemaphoreCreateBinary();
      esp_register_freertos_tick_hook(test_tick_hook);
      TEST_ASSERT(xSemaphoreTake(sem, portMAX_DELAY));
      esp_deregister_freertos_tick_hook(test_tick_hook);
      TEST_ESP_OK( esp_timer_delete(timer1) );
      vSemaphoreDelete(sem);
  }
  
  #if !defined(CONFIG_FREERTOS_UNICORE) && defined(CONFIG_ESP32_DPORT_WORKAROUND)
  
  #include "soc/dport_reg.h"
  #include "soc/frc_timer_reg.h"
  #include "esp_ipc.h"
  static bool task_stop;
  static bool time_jumped;
  
  static void task_check_time(void *p)
  {
      int64_t  t1 = 0, t2 = 0;
      while (task_stop == false) {
  
          t1 = t2;
          t2 = esp_timer_get_time();
          if (t1 > t2) {
              int64_t shift_us = t2 - t1;
              time_jumped = true;
              printf("System clock jumps back: %lli us\n", shift_us);
          }
  
          vTaskDelay(1);
      }
      vTaskDelete(NULL);
  }
  
  static void timer_callback(void* arg)
  {
  
  }
  
  static void dport_task(void *pvParameters)
  {
      while (task_stop == false) {
          DPORT_STALL_OTHER_CPU_START();
          ets_delay_us(3);
          DPORT_STALL_OTHER_CPU_END();
      }
      vTaskDelete(NULL);
  }
  
  TEST_CASE("esp_timer_impl_set_alarm does not set an alarm below the current time", "[esp_timer][timeout=62]")
  {
      const int max_timers = 2;
      time_jumped = false;
      task_stop   = false;
  
      xTaskCreatePinnedToCore(task_check_time, "task_check_time", 4096, NULL, 5, NULL, 0);
      // dport_task is used here to interrupt the esp_timer_impl_set_alarm function.
      // To interrupt it we can use an interrupt with 4 or 5 levels which will run on CPU0.
      // Instead, an interrupt we use the dport workaround which has 4 interrupt level for stall CPU0.
      xTaskCreatePinnedToCore(dport_task, "dport_task", 4096, NULL, 5, NULL, 1);
  
      const esp_timer_create_args_t periodic_timer_args = {
          .callback = &timer_callback,
      };
  
      esp_timer_handle_t periodic_timer[max_timers];
      printf("timers created\n");
  
      esp_timer_create(&periodic_timer_args, &periodic_timer[0]);
      esp_timer_start_periodic(periodic_timer[0], 9000);
  
      esp_timer_create(&periodic_timer_args, &periodic_timer[1]);
      esp_timer_start_periodic(periodic_timer[1], 9000);
  
      vTaskDelay(60 * 1000 / portTICK_PERIOD_MS);
      task_stop = true;
  
      esp_timer_stop(periodic_timer[0]);
      esp_timer_delete(periodic_timer[0]);
      esp_timer_stop(periodic_timer[1]);
      esp_timer_delete(periodic_timer[1]);
      printf("timers deleted\n");
  
      vTaskDelay(1000 / portTICK_PERIOD_MS);
  
      TEST_ASSERT(time_jumped == false);
  }
  
  
  static esp_timer_handle_t oneshot_timer;
  
  static void oneshot_timer_callback(void* arg)
  {
      esp_timer_start_once(oneshot_timer, 5000);
  }
  
  static const esp_timer_create_args_t oneshot_timer_args = {
      .callback = &oneshot_timer_callback,
  };
  
  TEST_CASE("esp_timer_impl_set_alarm and using start_once do not lead that the System time jumps back", "[esp_timer][timeout=62]")
  {
      time_jumped = false;
      task_stop   = false;
  
      xTaskCreatePinnedToCore(task_check_time, "task_check_time", 4096, NULL, 5, NULL, 0);
      // dport_task is used here to interrupt the esp_timer_impl_set_alarm function.
      // To interrupt it we can use an interrupt with 4 or 5 levels which will run on CPU0.
      // Instead, an interrupt we use the dport workaround which has 4 interrupt level for stall CPU0.
      xTaskCreatePinnedToCore(dport_task, "dport_task", 4096, NULL, 5, NULL, 1);
  
      const esp_timer_create_args_t periodic_timer_args = {
          .callback = &timer_callback,
      };
  
      esp_timer_handle_t periodic_timer;
  
      esp_timer_create(&periodic_timer_args, &periodic_timer);
      esp_timer_start_periodic(periodic_timer, 5000);
  
      esp_timer_create(&oneshot_timer_args, &oneshot_timer);
      esp_timer_start_once(oneshot_timer, 9990);
      printf("timers created\n");
  
      vTaskDelay(60 * 1000 / portTICK_PERIOD_MS);
      task_stop = true;
  
      esp_timer_stop(oneshot_timer);
      esp_timer_delete(oneshot_timer);
      printf("timers deleted\n");
  
      vTaskDelay(1000 / portTICK_PERIOD_MS);
  
      TEST_ASSERT(time_jumped == false);
  }
  
  #endif // !defined(CONFIG_FREERTOS_UNICORE) && defined(CONFIG_ESP32_DPORT_WORKAROUND)
  
  TEST_CASE("Test case when esp_timer_impl_set_alarm needs set timer < now_time", "[esp_timer]")
  {
  #ifdef CONFIG_ESP_TIMER_IMPL_FRC2
      REG_WRITE(FRC_TIMER_LOAD_REG(1), 0);
  #endif
      esp_timer_impl_advance(50331648); // 0xefffffff/80 = 50331647
  
      ets_delay_us(2);
  
      portDISABLE_INTERRUPTS();
      esp_timer_impl_set_alarm(50331647);
      uint64_t alarm_reg = esp_timer_impl_get_alarm_reg();
      uint64_t count_reg = esp_timer_impl_get_counter_reg();
      portENABLE_INTERRUPTS();
  
  #ifdef CONFIG_ESP_TIMER_IMPL_FRC2
      const uint32_t offset = 80 * 2; // s_timer_ticks_per_us
  #else
      const uint32_t offset = 2;
  #endif
  
      printf("alarm_reg = 0x%llx, count_reg 0x%llx\n", alarm_reg, count_reg);
      TEST_ASSERT(alarm_reg <= (count_reg + offset));
  }
  
  TEST_CASE("Test esp_timer_impl_set_alarm when the counter is near an overflow value", "[esp_timer]")
  {
      for (int i = 0; i < 1024; ++i) {
          uint32_t count_reg = 0xeffffe00 + i;
          REG_WRITE(FRC_TIMER_LOAD_REG(1), count_reg);
          printf("%d) count_reg = 0x%x\n", i, count_reg);
          esp_timer_impl_set_alarm(1); // timestamp is expired
      }
  }
  