Merge pull request #5829 from thinkyhead/rc_fix_isr_reentry

Combine fixes for LIN_ADVANCE and temperature ISR

Marlin/planner.cpp

   #endif
 
   #if ENABLED(LIN_ADVANCE)
-    const float target_float[XYZE] = { a, b, c, e },
-                de_float = target_float[E_AXIS] - position_float[E_AXIS],
-                mm_D_float = sqrt(sq(target_float[X_AXIS] - position_float[X_AXIS]) + sq(target_float[Y_AXIS] - position_float[Y_AXIS]));
-
-    memcpy(position_float, target_float, sizeof(position_float));
+    const float mm_D_float = sqrt(sq(a - position_float[X_AXIS]) + sq(b - position_float[Y_AXIS]));
   #endif
 
   const long da = target[X_AXIS] - position[X_AXIS],
   //*/
 
   // DRYRUN ignores all temperature constraints and assures that the extruder is instantly satisfied
-  if (DEBUGGING(DRYRUN)) position[E_AXIS] = target[E_AXIS];
+  if (DEBUGGING(DRYRUN)) {
+    position[E_AXIS] = target[E_AXIS];
+    #if ENABLED(LIN_ADVANCE)
+      position_float[E_AXIS] = e;
+    #endif
+  }
 
   long de = target[E_AXIS] - position[E_AXIS];
 
+  #if ENABLED(LIN_ADVANCE)
+    float de_float = e - position_float[E_AXIS];
+  #endif
+
   #if ENABLED(PREVENT_COLD_EXTRUSION)
     if (de) {
       if (thermalManager.tooColdToExtrude(extruder)) {
         position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
         de = 0; // no difference
+        #if ENABLED(LIN_ADVANCE)
+          position_float[E_AXIS] = e;
+          de_float = 0;
+        #endif
         SERIAL_ECHO_START;
         SERIAL_ECHOLNPGM(MSG_ERR_COLD_EXTRUDE_STOP);
       }
         if (labs(de) > (int32_t)axis_steps_per_mm[E_AXIS_N] * (EXTRUDE_MAXLENGTH)) { // It's not important to get max. extrusion length in a precision < 1mm, so save some cycles and cast to int
           position[E_AXIS] = target[E_AXIS]; // Behave as if the move really took place, but ignore E part
           de = 0; // no difference
+          #if ENABLED(LIN_ADVANCE)
+            position_float[E_AXIS] = e;
+            de_float = 0;
+          #endif
           SERIAL_ECHO_START;
           SERIAL_ECHOLNPGM(MSG_ERR_LONG_EXTRUDE_STOP);
         }
 
   // Update the position (only when a move was queued)
   memcpy(position, target, sizeof(position));
+  #if ENABLED(LIN_ADVANCE)
+    position_float[X_AXIS] = a;
+    position_float[Y_AXIS] = b;
+    position_float[Z_AXIS] = c;
+    position_float[E_AXIS] = e;
+  #endif
 
   recalculate();
 
        nb = position[Y_AXIS] = lround(b * axis_steps_per_mm[Y_AXIS]),
        nc = position[Z_AXIS] = lround(c * axis_steps_per_mm[Z_AXIS]),
        ne = position[E_AXIS] = lround(e * axis_steps_per_mm[_EINDEX]);
+  #if ENABLED(LIN_ADVANCE)
+    position_float[X_AXIS] = a;
+    position_float[Y_AXIS] = b;
+    position_float[Z_AXIS] = c;
+    position_float[E_AXIS] = e;
+  #endif
   stepper.set_position(na, nb, nc, ne);
   previous_nominal_speed = 0.0; // Resets planner junction speeds. Assumes start from rest.
   ZERO(previous_speed);
  */
 void Planner::sync_from_steppers() {
   LOOP_XYZE(i) position[i] = stepper.position((AxisEnum)i);
+  #if ENABLED(LIN_ADVANCE)
+    LOOP_XYZE(i) position_float[i] = stepper.position((AxisEnum)i) * steps_to_mm[i];
+  #endif
 }
 
 /**
     const uint8_t axis_index = axis;
   #endif
   position[axis] = lround(v * axis_steps_per_mm[axis_index]);
+  #if ENABLED(LIN_ADVANCE)
+    position_float[axis] = v;
+  #endif
   stepper.set_position(axis, v);
   previous_speed[axis] = 0.0;
 }

Marlin/stepper.cpp

   #endif
 }
 
-void Stepper::isr() {
-  #define _ENABLE_ISRs() cli(); SBI(TIMSK0, OCIE0B); ENABLE_STEPPER_DRIVER_INTERRUPT()
+#define _ENABLE_ISRs() do { cli(); if (thermalManager.in_temp_isr) CBI(TIMSK0, OCIE0B); else SBI(TIMSK0, OCIE0B); ENABLE_STEPPER_DRIVER_INTERRUPT(); } while(0)
 
-  uint16_t timer, remainder, ocr_val;
+void Stepper::isr() {
 
   static uint32_t step_remaining = 0;
 
+  uint16_t ocr_val;
+
   #define ENDSTOP_NOMINAL_OCR_VAL 3000    // check endstops every 1.5ms to guarantee two stepper ISRs within 5ms for BLTouch
   #define OCR_VAL_TOLERANCE 1000          // First max delay is 2.0ms, last min delay is 0.5ms, all others 1.5ms
 
     #define SPLIT(L) do { \
       _SPLIT(L); \
       if (ENDSTOPS_ENABLED && L > ENDSTOP_NOMINAL_OCR_VAL) { \
-        remainder = (uint16_t)L % (ENDSTOP_NOMINAL_OCR_VAL); \
+        uint16_t remainder = (uint16_t)L % (ENDSTOP_NOMINAL_OCR_VAL); \
         ocr_val = (remainder < OCR_VAL_TOLERANCE) ? ENDSTOP_NOMINAL_OCR_VAL + remainder : ENDSTOP_NOMINAL_OCR_VAL; \
         step_remaining = (uint16_t)L - ocr_val; \
       } \
 
     if (step_remaining && ENDSTOPS_ENABLED) {   // Just check endstops - not yet time for a step
       endstops.update();
-      ocr_val = step_remaining;
       if (step_remaining > ENDSTOP_NOMINAL_OCR_VAL) {
-        step_remaining = step_remaining - ENDSTOP_NOMINAL_OCR_VAL;
+        step_remaining -= ENDSTOP_NOMINAL_OCR_VAL;
         ocr_val = ENDSTOP_NOMINAL_OCR_VAL;
       }
-      else step_remaining = 0;  //  last one before the ISR that does the step
-      _NEXT_ISR(ocr_val);  //
+      else {
+        ocr_val = step_remaining;
+        step_remaining = 0;  //  last one before the ISR that does the step
+      }
+
+      _NEXT_ISR(ocr_val);
 
       NOLESS(OCR1A, TCNT1 + 16);
 
     NOLESS(OCR1A, TCNT1 + 16);
 
     // Restore original ISR settings
-    cli();
-    SBI(TIMSK0, OCIE0B);
-    ENABLE_STEPPER_DRIVER_INTERRUPT();
+    _ENABLE_ISRs();
   }
 
 #endif // ADVANCE or LIN_ADVANCE

Marlin/temperature.cpp

  */
 ISR(TIMER0_COMPB_vect) { Temperature::isr(); }
 
+volatile bool Temperature::in_temp_isr = false;
+
 void Temperature::isr() {
-  //Allow UART and stepper ISRs
+  // The stepper ISR can interrupt this ISR. When it does it re-enables this ISR
+  // at the end of its run, potentially causing re-entry. This flag prevents it.
+  if (in_temp_isr) return;
+  in_temp_isr = true;
+  
+  // Allow UART and stepper ISRs
   CBI(TIMSK0, OCIE0B); //Disable Temperature ISR
   sei();
 
     }
   #endif
 
+  cli();
+  in_temp_isr = false;
   SBI(TIMSK0, OCIE0B); //re-enable Temperature ISR
 }

Marlin/temperature.h

                  current_temperature_bed_raw,
                  target_temperature_bed;
 
+    static volatile bool in_temp_isr;
+
     #if ENABLED(TEMP_SENSOR_1_AS_REDUNDANT)
       static float redundant_temperature;
     #endif