Allow TMC baud rate override (#15773)

Marlin/src/module/stepper/trinamic.cpp

   TMC_SPI_DEFINE_E(5);
 #endif
 
+#ifndef TMC_BAUD_RATE
+  #define TMC_BAUD_RATE 115200
+#endif
+
 #if HAS_DRIVER(TMC2130)
   template<char AXIS_LETTER, char DRIVER_ID, AxisEnum AXIS_ID>
   void tmc_init(TMCMarlin<TMC2130Stepper, AXIS_LETTER, DRIVER_ID, AXIS_ID> &st, const uint16_t mA, const uint16_t microsteps, const uint32_t thrs, const bool stealth) {
   void tmc_serial_begin() {
     #if AXIS_HAS_UART(X)
       #ifdef X_HARDWARE_SERIAL
-        X_HARDWARE_SERIAL.begin(115200);
+        X_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperX.beginSerial(115200);
+        stepperX.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(X2)
       #ifdef X2_HARDWARE_SERIAL
-        X2_HARDWARE_SERIAL.begin(115200);
+        X2_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperX2.beginSerial(115200);
+        stepperX2.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(Y)
       #ifdef Y_HARDWARE_SERIAL
-        Y_HARDWARE_SERIAL.begin(115200);
+        Y_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperY.beginSerial(115200);
+        stepperY.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(Y2)
       #ifdef Y2_HARDWARE_SERIAL
-        Y2_HARDWARE_SERIAL.begin(115200);
+        Y2_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperY2.beginSerial(115200);
+        stepperY2.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(Z)
       #ifdef Z_HARDWARE_SERIAL
-        Z_HARDWARE_SERIAL.begin(115200);
+        Z_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperZ.beginSerial(115200);
+        stepperZ.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(Z2)
       #ifdef Z2_HARDWARE_SERIAL
-        Z2_HARDWARE_SERIAL.begin(115200);
+        Z2_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperZ2.beginSerial(115200);
+        stepperZ2.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(Z3)
       #ifdef Z3_HARDWARE_SERIAL
-        Z3_HARDWARE_SERIAL.begin(115200);
+        Z3_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperZ3.beginSerial(115200);
+        stepperZ3.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E0)
       #ifdef E0_HARDWARE_SERIAL
-        E0_HARDWARE_SERIAL.begin(115200);
+        E0_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE0.beginSerial(115200);
+        stepperE0.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E1)
       #ifdef E1_HARDWARE_SERIAL
-        E1_HARDWARE_SERIAL.begin(115200);
+        E1_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE1.beginSerial(115200);
+        stepperE1.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E2)
       #ifdef E2_HARDWARE_SERIAL
-        E2_HARDWARE_SERIAL.begin(115200);
+        E2_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE2.beginSerial(115200);
+        stepperE2.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E3)
       #ifdef E3_HARDWARE_SERIAL
-        E3_HARDWARE_SERIAL.begin(115200);
+        E3_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE3.beginSerial(115200);
+        stepperE3.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E4)
       #ifdef E4_HARDWARE_SERIAL
-        E4_HARDWARE_SERIAL.begin(115200);
+        E4_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE4.beginSerial(115200);
+        stepperE4.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
     #if AXIS_HAS_UART(E5)
       #ifdef E5_HARDWARE_SERIAL
-        E5_HARDWARE_SERIAL.begin(115200);
+        E5_HARDWARE_SERIAL.begin(TMC_BAUD_RATE);
       #else
-        stepperE5.beginSerial(115200);
+        stepperE5.beginSerial(TMC_BAUD_RATE);
       #endif
     #endif
   }

Marlin/src/pins/lpc1768/pins_BIGTREE_SKR_V1.3.h

   #define Z2_SERIAL_TX_PIN P1_04
   #define Z2_SERIAL_RX_PIN P1_01
 
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif
 
 //

Marlin/src/pins/lpc1768/pins_GMARSH_X6_REV1.h

   #define E1_SERIAL_RX_PIN P2_02
   #define E2_SERIAL_TX_PIN P2_06
   #define E2_SERIAL_RX_PIN P2_06
+
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #else
   #error "TMC2208 UART configuration is required for GMarsh X6."
 #endif

Marlin/src/pins/lpc1768/pins_MKS_SBASE.h

   #define Z_SERIAL_RX_PIN  P0_25   // TH3
   #define E0_SERIAL_TX_PIN P4_28   // J8-6
   #define E0_SERIAL_RX_PIN P0_26   // TH4
+
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif
 
 // UNUSED

Marlin/src/pins/lpc1768/pins_MKS_SGEN_L.h

   #define Z2_SERIAL_TX_PIN P4_29
   #define Z2_SERIAL_RX_PIN P1_17
 
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif // TMC2208 || TMC2209
 
 //

Marlin/src/pins/lpc1768/pins_RAMPS_RE_ARM.h

     #define E0_SERIAL_RX_PIN P2_08
   #endif
 
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif
 
 //

Marlin/src/pins/lpc1769/pins_MKS_SGEN.h

   #define Z_SERIAL_RX_PIN  P2_11   // J8-4
   #define E0_SERIAL_TX_PIN P2_13   // J8-5
   #define E0_SERIAL_RX_PIN P2_13   // J8-5
+  
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif

Marlin/src/pins/lpc1769/pins_TH3D_EZBOARD.h

   #define Z_SERIAL_RX_PIN  P0_20
   #define E0_SERIAL_TX_PIN P0_22
   #define E0_SERIAL_RX_PIN P0_21
+    
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif
 
 //

Marlin/src/pins/stm32/pins_BIGTREE_BTT002_V1.0.h

 
   //#define E2_SERIAL_TX_PIN PD6
   //#define E2_SERIAL_RX_PIN PD6
+
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200  
 #endif
 
 //

Marlin/src/pins/stm32/pins_BIGTREE_SKR_E3_DIP.h

   #define E0_SERIAL_TX_PIN PD2
   #define E0_SERIAL_RX_PIN PD2
 
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200  
 #endif
 
 //

Marlin/src/pins/stm32/pins_BIGTREE_SKR_PRO_V1.1.h

 
   #define E2_SERIAL_TX_PIN PD6
   #define E2_SERIAL_RX_PIN PD6
+
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200
 #endif
 
 //

Marlin/src/pins/stm32/pins_BTT_SKR_MINI_E3_V1_2.h

 
   #define E0_SERIAL_TX_PIN PC11
   #define E0_SERIAL_RX_PIN PC11
+
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200  
 #endif
 
 //

Marlin/src/pins/stm32/pins_FYSETC_CHEETAH_V12.h

   #define E0_SERIAL_TX_PIN PA2
   #define E0_SERIAL_RX_PIN PA3
 
+  // Reduce baud rate to improve software serial reliability
+  #define TMC_BAUD_RATE 19200  
 #endif