Followup to HAL_timer_restrain

Followup to #9985

Marlin/src/HAL/HAL_AVR/HAL_AVR.h

 
 #define _CAT(a, ...) a ## __VA_ARGS__
 #define HAL_timer_set_compare(timer, compare) (_CAT(TIMER_OCR_, timer) = compare)
-#define HAL_timer_restrain(timer, interval_us) NOLESS(_CAT(TIMER_OCR_, timer), _CAT(TIMER_COUNTER_, timer) + interval_us * HAL_TICKS_PER_US)
+#define HAL_timer_restrain(timer, interval_ticks) NOLESS(_CAT(TIMER_OCR_, timer), _CAT(TIMER_COUNTER_, timer) + interval_ticks)
 
 #define HAL_timer_get_compare(timer) _CAT(TIMER_OCR_, timer)
 #define HAL_timer_get_count(timer) _CAT(TIMER_COUNTER_, timer)

Marlin/src/HAL/HAL_DUE/HAL_timers_Due.h

   return pConfig->pTimerRegs->TC_CHANNEL[pConfig->channel].TC_CV;
 }
 
-FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us) {
-  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_us * HAL_TICKS_PER_US;
+FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks) {
+  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_ticks;
   if (HAL_timer_get_compare(timer_num) < mincmp) HAL_timer_set_compare(timer_num, mincmp);
 }
 

Marlin/src/HAL/HAL_LPC1768/HAL_timers.h

   return 0;
 }
 
-FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us) {
-  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_us * HAL_TICKS_PER_US;
+FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks) {
+  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_ticks;
   if (HAL_timer_get_compare(timer_num) < mincmp) HAL_timer_set_compare(timer_num, mincmp);
 }
 

Marlin/src/HAL/HAL_STM32F1/HAL_timers_Stm32f1.h

   }
 }
 
-FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us) {
-  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_us * HAL_TICKS_PER_US;
+FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks) {
+  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_ticks;
   if (HAL_timer_get_compare(timer_num) < mincmp) HAL_timer_set_compare(timer_num, mincmp);
 }
 

Marlin/src/HAL/HAL_STM32F7/HAL_timers_STM32F7.cpp

   return __HAL_TIM_GetCounter(&timerConfig[timer_num].timerdef);
 }
 
-void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us) {
-  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_us * HAL_TICKS_PER_US;
+void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks) {
+  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_ticks;
   if (HAL_timer_get_compare(timer_num) < mincmp) HAL_timer_set_compare(timer_num, mincmp);
 }
 

Marlin/src/HAL/HAL_STM32F7/HAL_timers_STM32F7.h

 void HAL_timer_set_compare(const uint8_t timer_num, const uint32_t compare);
 hal_timer_t HAL_timer_get_compare(const uint8_t timer_num);
 uint32_t HAL_timer_get_count(const uint8_t timer_num);
-void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us);
+void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks);
 
 void HAL_timer_isr_prologue(const uint8_t timer_num);
 

Marlin/src/HAL/HAL_TEENSY35_36/HAL_timers_Teensy.h

   return 0;
 }
 
-FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_us) {
-  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_us * HAL_TICKS_PER_US;
+FORCE_INLINE static void HAL_timer_restrain(const uint8_t timer_num, const uint16_t interval_ticks) {
+  const hal_timer_t mincmp = HAL_timer_get_count(timer_num) + interval_ticks;
   if (HAL_timer_get_compare(timer_num) < mincmp) HAL_timer_set_compare(timer_num, mincmp);
 }
 

Marlin/src/module/stepper.cpp

     _NEXT_ISR(ocr_val);
 
     #if DISABLED(LIN_ADVANCE)
-      HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL);
-      HAL_ENABLE_ISRs(); // re-enable ISRs
+      HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL * HAL_TICKS_PER_US);
+      HAL_ENABLE_ISRs();
     #endif
 
     return;
         if (current_block->steps[Z_AXIS] > 0) {
           enable_Z();
           _NEXT_ISR(HAL_STEPPER_TIMER_RATE / 1000); // Run at slow speed - 1 KHz
-          HAL_ENABLE_ISRs(); // re-enable ISRs
+          HAL_ENABLE_ISRs();
           return;
         }
       #endif
     }
     else {
       _NEXT_ISR(HAL_STEPPER_TIMER_RATE / 1000); // Run at slow speed - 1 KHz
-      HAL_ENABLE_ISRs(); // re-enable ISRs
+      HAL_ENABLE_ISRs();
       return;
     }
   }
   }
 
   #if DISABLED(LIN_ADVANCE)
-    HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL);
+    // Make sure stepper ISR doesn't monopolize the CPU
+    HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL * HAL_TICKS_PER_US);
   #endif
 
   // If current block is finished, reset pointer
     planner.discard_current_block();
   }
   #if DISABLED(LIN_ADVANCE)
-    HAL_ENABLE_ISRs(); // re-enable ISRs
+    HAL_ENABLE_ISRs();
   #endif
 }
 
       nextMainISR = 0;
     }
 
-    // Don't run the ISR faster than possible
-    // Make sure stepper interrupt does not monopolise CPU by adjusting compare to give about 8µs room
-    HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL);
+    // Make sure stepper ISR doesn't monopolize the CPU
+    HAL_timer_restrain(STEP_TIMER_NUM, STEP_TIMER_MIN_INTERVAL * HAL_TICKS_PER_US);
 
     // Restore original ISR settings
     HAL_ENABLE_ISRs();