tests-mbed_hal-common_tickers: Fix increment test case implementation

In case when base tick count is different than next tick count check first if the difference is equal to 1 tick (this is what we are looking for) if not then decrease the tick count.

Repeat counting process few times before incrementing the number of cycles in case when base tick count is equal to next tick count.

Author: mprse

TESTS/mbed_hal/common_tickers/main.cpp

@@ -344,20 +344,34 @@ void ticker_increment_test(void)
     } else {  // high frequency tickers
 
         uint32_t num_of_cycles = NUM_OF_CYCLES;
+        const uint32_t repeat_count = 20;
+        const uint32_t max_inc_val = 100;
 
         uint32_t base_tick_count = count_ticks(num_of_cycles, 1);
         uint32_t next_tick_count = base_tick_count;
         uint32_t inc_val = 0;
+        uint32_t repeat_cnt = 0;
 
-        while (inc_val < 100) {
-
+        while (inc_val < max_inc_val) {
             next_tick_count = count_ticks(num_of_cycles + inc_val, 1);
 
             if (next_tick_count == base_tick_count) {
 
-                /* Same tick count, so increase num of cycles. */
-                inc_val++;
+                /* Same tick count, so repeat 20 times and than
+                 * increase num of cycles by 1.
+                 */
+                if (repeat_cnt == repeat_count) {
+                    inc_val++;
+                    repeat_cnt = 0;
+                }
+
+                repeat_cnt++;
             } else {
+                /* Check if we got 1 tick diff. */
+                if (next_tick_count - base_tick_count == 1 ||
+                    base_tick_count - next_tick_count == 1) {
+                    break;
+                }
 
                 /* It is possible that the difference between base and next
                  * tick count on some platforms is greater that 1, in this case we need
@@ -366,12 +380,8 @@ void ticker_increment_test(void)
                  */
                 num_of_cycles /= 2;
                 inc_val = 0;
+                repeat_cnt = 0;
                 base_tick_count = count_ticks(num_of_cycles, 1);
-
-                if (next_tick_count - base_tick_count == 1 ||
-                    base_tick_count - next_tick_count == 1) {
-                    break;
-                }
             }
         }