[1.1.x] M303 thermal runaway protection (#8209)

* Added M303 thermal runaway protection

Currently, thermal runaway protection is not available during M303.
Therefore, if someone plugs the thermistors in incorrectly and goes to
autotune their printer, the printer temperature could runaway and damage
could occur.

* Replace removed line, clarifying its logic

Marlin/temperature.cpp

@@ -215,7 +215,7 @@ uint8_t Temperature::soft_pwm_amount[HOTENDS],
 
 #if HAS_PID_HEATING
 
-  void Temperature::PID_autotune(float temp, int hotend, int ncycles, bool set_result/*=false*/) {
+  void Temperature::PID_autotune(const float temp, const int8_t hotend, const int8_t ncycles, const bool set_result/*=false*/) {
     float input = 0.0;
     int cycles = 0;
     bool heating = true;
@@ -224,27 +224,59 @@ uint8_t Temperature::soft_pwm_amount[HOTENDS],
     long t_high = 0, t_low = 0;
 
     long bias, d;
-    float Ku, Tu;
-    float workKp = 0, workKi = 0, workKd = 0;
-    float max = 0, min = 10000;
+    float Ku, Tu,
+          workKp = 0, workKi = 0, workKd = 0,
+          max = 0, min = 10000;
+
+    #if WATCH_THE_BED || WATCH_HOTENDS
+      const float watch_temp_target =
+        #if ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED) && ENABLED(THERMAL_PROTECTION_HOTENDS) && ENABLED(PIDTEMP)
+          hotend < 0 ? temp - (WATCH_BED_TEMP_INCREASE + TEMP_BED_HYSTERESIS + 1) : temp - (WATCH_TEMP_INCREASE + TEMP_HYSTERESIS + 1)
+        #elif ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED)
+          temp - (WATCH_BED_TEMP_INCREASE + TEMP_BED_HYSTERESIS + 1)
+        #else
+          temp - (WATCH_TEMP_INCREASE + TEMP_HYSTERESIS + 1)
+        #endif
+      ;
+      const int8_t watch_temp_period =
+        #if ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED) && ENABLED(THERMAL_PROTECTION_HOTENDS) && ENABLED(PIDTEMP)
+          hotend < 0 ? temp - THERMAL_PROTECTION_BED_PERIOD : THERMAL_PROTECTION_PERIOD
+        #elif ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED)
+          THERMAL_PROTECTION_BED_PERIOD
+        #else
+          THERMAL_PROTECTION_PERIOD
+        #endif
+      ;
+      const int8_t hysteresis =
+        #if ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED) && ENABLED(THERMAL_PROTECTION_HOTENDS) && ENABLED(PIDTEMP)
+          hotend < 0 ? TEMP_BED_HYSTERESIS : TEMP_HYSTERESIS
+        #elif ENABLED(THERMAL_PROTECTION_BED) && ENABLED(PIDTEMPBED)
+          TEMP_BED_HYSTERESIS
+        #else
+          TEMP_HYSTERESIS
+        #endif
+      ;
+      millis_t temp_change_ms = temp_ms + watch_temp_period * 1000UL;
+      float next_watch_temp = 0.0;
+      bool heated = false;
+    #endif
 
     #if HAS_AUTO_FAN
       next_auto_fan_check_ms = temp_ms + 2500UL;
     #endif
 
-    if (hotend >=
-        #if ENABLED(PIDTEMP)
-          HOTENDS
-        #else
-          0
-        #endif
-      || hotend <
-        #if ENABLED(PIDTEMPBED)
-          -1
-        #else
-          0
-        #endif
-    ) {
+    #if ENABLED(PIDTEMP)
+      #define _TOP_HOTEND HOTENDS - 1
+    #else
+      #define _TOP_HOTEND -1
+    #endif
+    #if ENABLED(PIDTEMPBED)
+      #define _BOT_HOTEND -1
+    #else
+      #define _BOT_HOTEND 0
+    #endif
+
+    if (!WITHIN(hotend, _BOT_HOTEND, _TOP_HOTEND)) {
       SERIAL_ECHOLN(MSG_PID_BAD_EXTRUDER_NUM);
       return;
     }
@@ -330,7 +362,7 @@ uint8_t Temperature::soft_pwm_amount[HOTENDS],
               ;
               bias += (d * (t_high - t_low)) / (t_low + t_high);
               bias = constrain(bias, 20, max_pow - 20);
-              d = (bias > max_pow / 2) ? max_pow - 1 - bias : bias;
+              d = (bias > max_pow >> 1) ? max_pow - 1 - bias : bias;
 
               SERIAL_PROTOCOLPAIR(MSG_BIAS, bias);
               SERIAL_PROTOCOLPAIR(MSG_D, d);
@@ -394,6 +426,16 @@ uint8_t Temperature::soft_pwm_amount[HOTENDS],
         #endif
 
         temp_ms = ms + 2000UL;
+
+        #if WATCH_THE_BED || WATCH_HOTENDS
+          if (!heated && input > next_watch_temp) {
+            if (input > watch_temp_target) heated = true;
+            next_watch_temp = input + hysteresis;
+            temp_change_ms = ms + watch_temp_period * 1000UL;
+          }
+          else if ((!heated && ELAPSED(ms, temp_change_ms)) || (heated && input < temp - MAX_OVERSHOOT_PID_AUTOTUNE))
+            _temp_error(hotend, PSTR(MSG_T_THERMAL_RUNAWAY), PSTR(MSG_THERMAL_RUNAWAY));
+        #endif
       } // every 2 seconds
       // Timeout after 20 minutes since the last undershoot/overshoot cycle
       if (((ms - t1) + (ms - t2)) > (20L * 60L * 1000L)) {

Marlin/temperature.h

@@ -437,7 +437,7 @@ class Temperature {
      * Perform auto-tuning for hotend or bed in response to M303
      */
     #if HAS_PID_HEATING
-      static void PID_autotune(float temp, int hotend, int ncycles, bool set_result=false);
+      static void PID_autotune(const float temp, const int8_t hotend, const int8_t ncycles, const bool set_result=false);
     #endif
 
     /**