Fix AXIS_HAS_SW_SERIAL

Marlin/src/core/drivers.h

 #define AXIS_HAS_UART(A) (    AXIS_DRIVER_TYPE(A,TMC2208) \
                            || AXIS_DRIVER_TYPE(A,TMC2209) )
 
-#define AXIS_HAS_SW_SERIAL(A) ((AXIS_HAS_UART(A) && !defined(A##_HARDWARE_SERIAL)))
+#define AXIS_HAS_SW_SERIAL(A) ((AXIS_HAS_UART(A) && !HAS_##A##_HARDWARE_SERIAL))
 
 #define AXIS_HAS_STALLGUARD(A)   (    AXIS_DRIVER_TYPE(A,TMC2130) \
                                    || AXIS_DRIVER_TYPE(A,TMC2160) \

Marlin/src/inc/Conditionals_post.h

 #define HAS_Z4_MAX (PIN_EXISTS(Z4_MAX))
 #define HAS_Z_MIN_PROBE_PIN (HAS_CUSTOM_PROBE_PIN && PIN_EXISTS(Z_MIN_PROBE))
 
+// Cannot use a macro with a defined() statement inside REPEAT macros.
+// [AXIS]_HARDWARE_SERIAL definitions are typically strings which cannot be
+// tested directly, as they will evaluate to 0.
+#ifdef X_HARDWARE_SERIAL
+  #define HAS_X_HARDWARE_SERIAL 1
+#endif
+#ifdef X2_HARDWARE_SERIAL
+  #define HAS_X2_HARDWARE_SERIAL 1
+#endif
+#ifdef Y_HARDWARE_SERIAL
+  #define HAS_Y_HARDWARE_SERIAL 1
+#endif
+#ifdef Y2_HARDWARE_SERIAL
+  #define HAS_Y2_HARDWARE_SERIAL 1
+#endif
+#ifdef Z_HARDWARE_SERIAL
+  #define HAS_Z_HARDWARE_SERIAL 1
+#endif
+#ifdef Z2_HARDWARE_SERIAL
+  #define HAS_Z2_HARDWARE_SERIAL 1
+#endif
+#ifdef Z3_HARDWARE_SERIAL
+  #define HAS_Z3_HARDWARE_SERIAL 1
+#endif
+#ifdef Z4_HARDWARE_SERIAL
+  #define HAS_Z4_HARDWARE_SERIAL 1
+#endif
+#ifdef E0_HARDWARE_SERIAL
+  #define HAS_E0_HARDWARE_SERIAL 1
+#endif
+#ifdef E1_HARDWARE_SERIAL
+  #define HAS_E1_HARDWARE_SERIAL 1
+#endif
+#ifdef E2_HARDWARE_SERIAL
+  #define HAS_E2_HARDWARE_SERIAL 1
+#endif
+#ifdef E3_HARDWARE_SERIAL
+  #define HAS_E3_HARDWARE_SERIAL 1
+#endif
+#ifdef E4_HARDWARE_SERIAL
+  #define HAS_E4_HARDWARE_SERIAL 1
+#endif
+#ifdef E5_HARDWARE_SERIAL
+  #define HAS_E5_HARDWARE_SERIAL 1
+#endif
+#ifdef E6_HARDWARE_SERIAL
+  #define HAS_E6_HARDWARE_SERIAL 1
+#endif
+#ifdef E7_HARDWARE_SERIAL
+  #define HAS_E7_HARDWARE_SERIAL 1
+#endif
+
+
 //
 // ADC Temp Sensors (Thermistor or Thermocouple with amplifier ADC interface)
 //

buildroot/share/tests/esp32-tests

 opt_add WEBSUPPORT
 exec_test $1 $2 "ESP32 with WIFISUPPORT and WEBSUPPORT"
 
+#
+# Build with TMC drivers using hardware serial
+#
+restore_configs
+opt_set MOTHERBOARD BOARD_ESPRESSIF_ESP32
+opt_set X_DRIVER_TYPE TMC2209
+opt_set Y_DRIVER_TYPE TMC2208
+opt_set Z_DRIVER_TYPE TMC2209
+opt_set E0_DRIVER_TYPE TMC2209
+opt_set X_HARDWARE_SERIAL Serial1
+opt_set Y_HARDWARE_SERIAL Serial1
+opt_set Z_HARDWARE_SERIAL Serial1
+opt_set E0_HARDWARE_SERIAL Serial1
+exec_test $1 $2 "ESP32 with TMC Hardware Serial"
+
 # cleanup
 restore_configs