🚀 HAL for GD32 MFL (Creality v4.2.2) (#27744)

.github/workflows/ci-build-tests.yml

@@ -151,6 +151,9 @@ jobs:
         # HC32
         - HC32F460C_aquila_101
 
+        # GD32F3
+        - GD32F303RE_creality_mfl
+
         # LPC176x - Lengthy tests
         - LPC1768
         - LPC1769

Marlin/src/HAL/GD32_MFL/HAL.cpp

@@ -0,0 +1,120 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+#include "../shared/Delay.h"
+
+uint16_t MarlinHAL::adc_result;
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+  extern void install_min_serial();
+#endif
+
+#if ENABLED(MARLIN_DEV_MODE)
+  // Dump the clock frequencies of the system, AHB, APB1, APB2, and F_CPU.
+  static inline void HAL_clock_frequencies_dump() {
+    auto& rcuInstance = rcu::RCU::get_instance();
+    uint32_t freq = rcuInstance.get_clock_frequency(rcu::Clock_Frequency::CK_SYS);
+    SERIAL_ECHOPGM("\nSYSTEM_CLOCK=", freq);
+    freq = rcuInstance.get_clock_frequency(rcu::Clock_Frequency::CK_AHB);
+    SERIAL_ECHOPGM("\nABH_CLOCK=", freq);
+    freq = rcuInstance.get_clock_frequency(rcu::Clock_Frequency::CK_APB1);
+    SERIAL_ECHOPGM("\nAPB1_CLOCK=", freq);
+    freq = rcuInstance.get_clock_frequency(rcu::Clock_Frequency::CK_APB2);
+    SERIAL_ECHOPGM("\nAPB2_CLOCK=", freq,
+    "\nF_CPU=", F_CPU);
+    // Done
+    SERIAL_ECHOPGM("\n--\n");
+  }
+#endif  // MARLIN_DEV_MODE
+
+// Initializes the Marlin HAL
+void MarlinHAL::init() {
+  constexpr unsigned int cpuFreq = F_CPU;
+  UNUSED(cpuFreq);
+
+#if PIN_EXISTS(LED)
+  OUT_WRITE(LED_PIN, LOW);
+#endif
+
+  SetTimerInterruptPriorities();
+
+  // Print clock frequencies to host serial
+  TERN_(MARLIN_DEV_MODE, HAL_clock_frequencies_dump());
+
+  // Register min serial
+  TERN_(POSTMORTEM_DEBUGGING, install_min_serial());
+}
+
+// Returns the reset source based on the flags set in the RCU module
+uint8_t MarlinHAL::get_reset_source() {
+  return
+    (RCU_I.get_flag(rcu::Status_Flags::FLAG_FWDGTRST)) ? RST_WATCHDOG :
+    (RCU_I.get_flag(rcu::Status_Flags::FLAG_SWRST)) ? RST_SOFTWARE :
+    (RCU_I.get_flag(rcu::Status_Flags::FLAG_EPRST)) ? RST_EXTERNAL :
+    (RCU_I.get_flag(rcu::Status_Flags::FLAG_PORRST)) ? RST_POWER_ON :
+    (RCU_I.get_flag(rcu::Status_Flags::FLAG_LPRST)) ? RST_BROWN_OUT :
+    0;
+}
+
+// Returns the amount of free memory available in bytes
+int MarlinHAL::freeMemory() {
+  volatile char top;
+  return &top - reinterpret_cast<char*>(_sbrk(0));
+}
+
+// Watchdog Timer
+#if ENABLED(USE_WATCHDOG)
+  #define WDT_TIMEOUT_US  TERN(WATCHDOG_DURATION_8S, 8000000, 4000000)  // 4 or 8 second timeout
+
+  #include <FWatchdogTimer.h>
+
+  FWatchdogTimer& watchdogTimer = FWatchdogTimer::get_instance();
+
+  // Initializes the watchdog timer
+  void MarlinHAL::watchdog_init() {
+    IF_DISABLED(DISABLE_WATCHDOG_INIT, watchdogTimer.begin(WDT_TIMEOUT_US));
+  }
+
+  // Refreshes the watchdog timer to prevent system reset
+  void MarlinHAL::watchdog_refresh() {
+    watchdogTimer.reload();
+    #if DISABLED(PINS_DEBUGGING) && PIN_EXISTS(LED)
+      TOGGLE(LED_PIN);  // Heartbeat indicator
+    #endif
+  }
+#endif
+
+extern "C" {
+  extern unsigned int _ebss;  // End of bss section
+}
+
+// Resets the system to initiate a firmware flash.
+WEAK void flashFirmware(const int16_t) {
+  hal.reboot();
+}
+
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/HAL.h

@@ -0,0 +1,158 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#define CPU_32_BIT
+
+#include "../../core/macros.h"
+#include "../shared/Marduino.h"
+#include "../shared/math_32bit.h"
+#include "../shared/HAL_SPI.h"
+
+#include "temp_soc.h"
+#include "fastio.h"
+#include "Servo.h"
+
+#include "../../inc/MarlinConfigPre.h"
+
+#include <stdint.h>
+#include <GPIO.hpp>
+#include <AFIO.hpp>
+
+// Default graphical display delays
+#define CPU_ST7920_DELAY_1 300
+#define CPU_ST7920_DELAY_2  40
+#define CPU_ST7920_DELAY_3 340
+
+// Serial Ports
+#include "MarlinSerial.h"
+
+// Interrupts
+#define CRITICAL_SECTION_START()  const bool irqon = !__get_PRIMASK(); __disable_irq()
+#define CRITICAL_SECTION_END()    if (irqon) __enable_irq()
+
+#define cli() __disable_irq()
+#define sei() __enable_irq()
+
+// Alias of __bss_end__
+#define __bss_end __bss_end__
+
+// Types
+typedef double isr_float_t; // FPU ops are used for single-precision, so use double for ISRs.
+typedef uint8_t pin_t;      // Parity with mfl platform
+
+// Servo
+class libServo;
+typedef libServo hal_servo_t;
+#define PAUSE_SERVO_OUTPUT()  libServo::pause_all_servos()
+#define RESUME_SERVO_OUTPUT() libServo::resume_all_servos()
+
+// Debugging
+#define JTAG_DISABLE()    AFIO_I.set_remap(gpio::Pin_Remap_Select::SWJ_DP_ONLY_REMAP)
+#define JTAGSWD_DISABLE() AFIO_I.set_remap(gpio::Pin_Remap_Select::SWJ_ALL_DISABLED_REMAP)
+#define JTAGSWD_RESET()   AFIO_I.set_remap(gpio::Pin_Remap_Select::FULL_SWJ_REMAP)
+
+// ADC
+#ifdef ADC_RESOLUTION
+  #define HAL_ADC_RESOLUTION  ADC_RESOLUTION
+#else
+  #define HAL_ADC_RESOLUTION  12
+#endif
+
+#define HAL_ADC_VREF_MV   3300
+
+// Disable Marlin's software oversampling.
+// The MFL framework uses 16x hardware oversampling by default
+#define HAL_ADC_FILTERED
+
+#define GET_PIN_MAP_PIN(index)        index
+#define GET_PIN_MAP_INDEX(pin)        pin
+#define PARSED_PIN_INDEX(code, dval)  parser.intval(code, dval)
+
+#ifndef PLATFORM_M997_SUPPORT
+  #define PLATFORM_M997_SUPPORT
+#endif
+
+void flashFirmware(const int16_t);
+
+#define HAL_CAN_SET_PWM_FREQ    // This HAL supports PWM Frequency adjustment
+
+extern "C" char* _sbrk(int incr);
+extern "C" char* dtostrf(double val, signed char width, unsigned char prec, char* sout);
+
+// MarlinHAL Class
+class MarlinHAL {
+public:
+  // Before setup()
+  MarlinHAL() {}
+
+  // Watchdog
+  static void watchdog_init()    IF_DISABLED(USE_WATCHDOG, {});
+  static void watchdog_refresh() IF_DISABLED(USE_WATCHDOG, {});
+
+  static void init();                             // called early in setup()
+  static void init_board() {}                     // called less early in setup()
+  static void reboot() { NVIC_SystemReset(); }    // restart the firmware from 0x0
+
+  // Interrupts
+  static bool isr_state() { return !__get_PRIMASK(); }
+  static void isr_on() { sei(); }
+  static void isr_off() { cli(); }
+  static void delay_ms(const int ms) { delay(ms); }
+
+  // Tasks called from idle()
+  static void idletask() {}
+
+  // Reset
+  static uint8_t get_reset_source();
+  static void clear_reset_source() { RCU_I.clear_all_reset_flags(); }
+
+  // Free SRAM
+  static int freeMemory();
+
+  // ADC methods
+  static uint16_t adc_result;
+
+  // Called by Temperature::init once at startup
+  static void adc_init() { analogReadResolution(HAL_ADC_RESOLUTION); }
+
+  // Called by Temperature::init for each sensor at startup
+  static void adc_enable(const pin_t pin) { pinMode(pin, INPUT); }
+
+  // Called from Temperature::isr to start ADC sampling on the given pin
+  static void adc_start(const pin_t pin) { adc_result = static_cast<uint16_t>(analogRead(pin)); }
+
+  // Check if ADC is ready for reading
+  static bool adc_ready() { return true; }
+
+  // Current value of the ADC register
+  static uint16_t adc_value() { return adc_result; }
+
+  // Set the PWM duty cycle for the pin to the given value.
+  // Optionally invert the duty cycle [default = false]
+  // Optionally change the maximum size of the provided value to enable finer PWM duty control [default = 255]
+  static void set_pwm_duty(const pin_t pin, const uint16_t value, const uint16_t scale = 255U, const bool invert = false);
+
+  // Set the frequency of the timer for the given pin.
+  // All Timer PWM pins run at the same frequency.
+  static void set_pwm_frequency(const pin_t pin, const uint16_t f_desired);
+};

Marlin/src/HAL/GD32_MFL/MarlinSPI.h

@@ -0,0 +1,26 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include <SPI.h>
+
+using MarlinSPI = SPIClass;

Marlin/src/HAL/GD32_MFL/MarlinSerial.cpp

@@ -0,0 +1,101 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+#include "MarlinSerial.h"
+
+#if ENABLED(EMERGENCY_PARSER)
+  #include "../../feature/e_parser.h"
+#endif
+
+using namespace arduino;
+
+MarlinSerial& MarlinSerial::get_instance(usart::USART_Base Base, pin_size_t rxPin, pin_size_t txPin) {
+  UsartSerial& serial = UsartSerial::get_instance(Base, rxPin, txPin);
+  return *reinterpret_cast<MarlinSerial*>(&serial);
+}
+
+#if USING_HW_SERIAL0
+  MSerialT MSerial0(true, MarlinSerial::get_instance(usart::USART_Base::USART0_BASE, NO_PIN, NO_PIN));
+#endif
+#if USING_HW_SERIAL1
+  MSerialT MSerial1(true, MarlinSerial::get_instance(usart::USART_Base::USART1_BASE, NO_PIN, NO_PIN));
+#endif
+#if USING_HW_SERIAL2
+  MSerialT MSerial2(true, MarlinSerial::get_instance(usart::USART_Base::USART2_BASE, NO_PIN, NO_PIN));
+#endif
+#if USING_HW_SERIAL3
+  MSerialT MSerial3(true, MarlinSerial::get_instance(usart::USART_Base::UART3_BASE, NO_PIN, NO_PIN));
+#endif
+#if USING_HW_SERIAL4
+  MSerialT MSerial4(true, MarlinSerial::get_instance(usart::USART_Base::UART4_BASE, NO_PIN, NO_PIN));
+#endif
+
+#if ENABLED(EMERGENCY_PARSER)
+  // This callback needs to access the specific MarlinSerial instance
+  // We'll use a static pointer to track the current instance
+  static MarlinSerial* current_serial_instance = nullptr;
+
+  static void emergency_callback() {
+    if (current_serial_instance) {
+      uint8_t last_data = current_serial_instance->get_last_data();
+      emergency_parser.update(current_serial_instance->emergency_state, last_data);
+    }
+  }
+
+  void MarlinSerial::register_emergency_callback(void (*callback)()) {
+    usart_.register_interrupt_callback(usart::Interrupt_Type::INTR_RBNEIE, callback);
+  }
+#endif
+
+void MarlinSerial::begin(unsigned long baudrate, uint16_t config) {
+  UsartSerial::begin(baudrate, config);
+  #if DISABLED(SERIAL_DMA)
+    #if ENABLED(EMERGENCY_PARSER)
+      current_serial_instance = this;
+      register_emergency_callback(emergency_callback);
+    #endif
+  #endif
+}
+
+void MarlinSerial::updateRxDmaBuffer() {
+  #if ENABLED(EMERGENCY_PARSER)
+    // Get the number of bytes available in the receive buffer
+    size_t available_bytes = usart_.available_for_read(true);
+    uint8_t data;
+
+    // Process only the available data
+    for (size_t i = 0; i < available_bytes; ++i) {
+      if (usart_.read_rx_buffer(data)) {
+        emergency_parser.update(emergency_state, data);
+      }
+    }
+  #endif
+  // Call the base class implementation to handle any additional updates
+  UsartSerial::updateRxDmaBuffer();
+}
+
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/MarlinSerial.h

@@ -0,0 +1,75 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../inc/MarlinConfigPre.h"
+
+#if ENABLED(EMERGENCY_PARSER)
+  #include "../../feature/e_parser.h"
+#endif
+
+#include <UsartSerial.hpp>
+
+#include "../../core/serial_hook.h"
+
+#define SERIAL_INDEX_MIN 0
+#define SERIAL_INDEX_MAX 4
+
+#include "../shared/serial_ports.h"
+
+#if defined(LCD_SERIAL_PORT) && ANY(HAS_DGUS_LCD, EXTENSIBLE_UI)
+  #define LCD_SERIAL_TX_BUFFER_FREE() LCD_SERIAL.availableForWrite()
+#endif
+
+using namespace arduino;
+
+struct MarlinSerial : public UsartSerial {
+  static MarlinSerial& get_instance(usart::USART_Base Base, pin_size_t rxPin = NO_PIN, pin_size_t txPin = NO_PIN);
+
+  void begin(unsigned long baudrate, uint16_t config);
+  inline void begin(unsigned long baudrate) { begin(baudrate, SERIAL_8N1); }
+  void updateRxDmaBuffer();
+
+  #if DISABLED(SERIAL_DMA)
+    FORCE_INLINE static uint8_t buffer_overruns() { return 0; }
+  #endif
+
+  #if ENABLED(EMERGENCY_PARSER)
+    EmergencyParser::State emergency_state;
+
+    // Accessor method to get the last received byte
+    uint8_t get_last_data() { return usart_.get_last_data(); }
+
+    // Register the emergency callback
+    void register_emergency_callback(void (*callback)());
+  #endif
+
+protected:
+  using UsartSerial::UsartSerial;
+};
+
+typedef Serial1Class<MarlinSerial> MSerialT;
+extern MSerialT MSerial0;
+extern MSerialT MSerial1;
+extern MSerialT MSerial2;
+extern MSerialT MSerial3;
+extern MSerialT MSerial4;

Marlin/src/HAL/GD32_MFL/MinSerial.cpp

@@ -0,0 +1,163 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfigPre.h"
+
+#if ENABLED(POSTMORTEM_DEBUGGING)
+#include "../shared/MinSerial.h"
+
+// Base addresses for USART peripherals
+static constexpr uintptr_t USART_base[] = {
+  0x40013800, // USART0
+  0x40004400, // USART1
+  0x40004800, // USART2
+  0x40004C00, // UART3
+  0x40005000  // UART4
+};
+
+// Register offsets
+static constexpr uint32_t STAT0_OFFSET = 0x00U;
+static constexpr uint32_t DATA_OFFSET = 0x04U;
+static constexpr uint32_t BAUD_OFFSET = 0x08U;
+static constexpr uint32_t CTL0_OFFSET = 0x0CU;
+static constexpr uint32_t CTL1_OFFSET = 0x14U;
+
+// Bit positions
+static constexpr uint32_t TBE_BIT = 7;
+static constexpr uint32_t TEN_BIT = 3;
+static constexpr uint32_t UEN_BIT = 13;
+
+// NVIC interrupt numbers for USART
+static constexpr int nvicUART[] = { 37, 38, 39, 52, 53 };
+
+// RCU PCLK values for USART
+static constexpr rcu::RCU_PCLK clockRegs[] = {
+  rcu::RCU_PCLK::PCLK_USART0,
+  rcu::RCU_PCLK::PCLK_USART1,
+  rcu::RCU_PCLK::PCLK_USART2,
+  rcu::RCU_PCLK::PCLK_UART3,
+  rcu::RCU_PCLK::PCLK_UART4
+};
+
+// Memory barrier instructions
+#define isb() __asm__ __volatile__ ("isb" : : : "memory")
+#define dsb() __asm__ __volatile__ ("dsb" : : : "memory")
+#define sw_barrier() __asm__ volatile("" : : : "memory")
+
+// Direct register access macros
+#define USART_REG(offset) (*(volatile uint32_t*)(USART_base[SERIAL_PORT] + (offset)))
+#define USART_STAT0 USART_REG(STAT0_OFFSET)
+#define USART_DATA  USART_REG(DATA_OFFSET)
+#define USART_BAUD  USART_REG(BAUD_OFFSET)
+#define USART_CTL0  USART_REG(CTL0_OFFSET)
+#define USART_CTL1  USART_REG(CTL1_OFFSET)
+
+// Bit manipulation macros
+#define READ_BIT(reg, bit) (((reg) >> (bit)) & 1U)
+#define SET_BIT(reg, bit) ((reg) |= (1U << (bit)))
+#define CLEAR_BIT(reg, bit) ((reg) &= ~(1U << (bit)))
+
+// Initializes the MinSerial interface.
+// This function sets up the USART interface for serial communication.
+// If the selected serial port is not a hardware port, it disables the severe error reporting feature.
+static void MinSerialBegin() {
+  #if !WITHIN(SERIAL_PORT, 0, 4)
+    #warning "Using POSTMORTEM_DEBUGGING requires a physical U(S)ART hardware in case of severe error."
+    #warning "Disabling the severe error reporting feature currently because the used serial port is not a HW port."
+  #else
+    int nvicIndex = nvicUART[SERIAL_PORT];
+
+    // NVIC base address for interrupt disable
+    struct NVICMin {
+      volatile uint32_t ISER[32];
+      volatile uint32_t ICER[32];
+    };
+    NVICMin *nvicBase = (NVICMin*)0xE000E100;
+  
+    SBI32(nvicBase->ICER[nvicIndex >> 5], nvicIndex & 0x1F);
+
+    // We require memory barriers to properly disable interrupts
+    // (https://dzone.com/articles/nvic-disabling-interrupts-on-arm-cortex-m-and-the)
+    dsb();
+    isb();
+
+    // Get the RCU PCLK for this USART
+    rcu::RCU_PCLK pclk = clockRegs[SERIAL_PORT];
+
+    // Disable then enable usart peripheral clocks
+    rcu::RCU_DEVICE.set_pclk_enable(pclk, false);
+    rcu::RCU_DEVICE.set_pclk_enable(pclk, true);
+
+    // Save current baudrate
+    uint32_t baudrate = USART_BAUD;
+
+    // Reset USART control registers
+    USART_CTL0 = 0;
+    USART_CTL1 = 0; // 1 stop bit
+
+    // Restore baudrate
+    USART_BAUD = baudrate;
+
+    // Enable transmitter and USART (8 bits, no parity, 1 stop bit)
+    SET_BIT(USART_CTL0, TEN_BIT);
+    SET_BIT(USART_CTL0, UEN_BIT);
+  #endif
+}
+
+// Writes a single character to the serial port.
+static void MinSerialWrite(char c) {
+  #if WITHIN(SERIAL_PORT, 0, 4)
+    // Wait until transmit buffer is empty
+    while (!READ_BIT(USART_STAT0, TBE_BIT)) {
+      hal.watchdog_refresh();
+      sw_barrier();
+    }
+    // Write character to data register
+    USART_DATA = c;
+  #endif
+}
+
+// Installs the minimum serial interface.
+// Sets the HAL_min_serial_init and HAL_min_serial_out function pointers to MinSerialBegin and MinSerialWrite respectively.
+void install_min_serial() {
+  HAL_min_serial_init = &MinSerialBegin;
+  HAL_min_serial_out = &MinSerialWrite;
+}
+
+extern "C" {
+  // A low-level assembly-based jump handler.
+  // Unconditionally branches to the CommonHandler_ASM function.
+  __attribute__((naked, aligned(4))) void JumpHandler_ASM() {
+    __asm__ __volatile__ ("b CommonHandler_ASM\n");
+  }
+  void __attribute__((naked, alias("JumpHandler_ASM"), nothrow)) HardFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"), nothrow)) BusFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"), nothrow)) UsageFault_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"), nothrow)) MemManage_Handler();
+  void __attribute__((naked, alias("JumpHandler_ASM"), nothrow)) NMI_Handler();
+}
+
+#endif // POSTMORTEM_DEBUGGING
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/README.md

@@ -0,0 +1,8 @@
+# Generic GD32 HAL based on the MFL Arduino Core
+
+This HAL is eventually intended to act as the generic HAL for all GD32 chips using the MFL library.
+
+Currently it supports:
+ * GD32F303RET6
+
+Targeting the official [MFL Arduino Core](https://github.com/bnmguy/ArduinoCore_MFL).

Marlin/src/HAL/GD32_MFL/SDCard.h

@@ -0,0 +1,214 @@
+//
+// MFL gd32f30x SDCARD using DMA through SDIO in C++
+//
+// Copyright (C) 2025 B. Mourit <bnmguy@gmail.com>
+//
+// This software is free software: you can redistribute it and/or modify it under the terms of the
+// GNU Lesser General Public License as published by the Free Software Foundation,
+// either version 3 of the License, or (at your option) any later version.
+//
+// This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+// without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+// See the GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License along with this software.
+// If not, see <https://www.gnu.org/licenses/>.
+//
+#pragma once
+
+#include "../../inc/MarlinConfig.h"
+
+#include "SDIO.hpp"
+
+namespace sdio {
+
+class DMA;
+
+class CardDMA {
+public:
+  static CardDMA& get_instance();
+
+  SDIO_Error_Type init();
+  SDIO_Error_Type card_init();
+  SDIO_Error_Type begin_startup_procedure();
+  void begin_shutdown_procedure();
+  // Configuration
+  SDIO_Error_Type set_hardware_bus_width(Bus_Width width);
+  // Main read/write functions for single and multiblock transfers
+  SDIO_Error_Type read(uint8_t* buf, uint32_t address, uint32_t count);
+  SDIO_Error_Type write(uint8_t* buf, uint32_t address, uint32_t count);
+  // DMA transfers
+  // Other card functions
+  SDIO_Error_Type erase(uint32_t address_start, uint32_t address_end);
+  // Interrupt handler
+  void handle_interrupts();
+  // Card select
+  SDIO_Error_Type select_deselect();
+
+  SDIO_Error_Type get_card_interface_status(uint32_t* status);
+  SDIO_Error_Type get_sdcard_status(uint32_t* status);
+
+  void check_dma_complete();
+  SDIO_Error_Type stop_transfer();
+
+  Transfer_State get_transfer_state();
+  uint32_t get_card_capacity() const;
+
+  SDIO_Error_Type send_bus_width_command(uint32_t width_value);
+
+  SDIO_Error_Type get_card_specific_data(Card_Info* info);
+  constexpr Block_Size get_data_block_size_index(uint16_t size);
+
+  SDIO_Error_Type get_card_state(Card_State* card_state);
+  SDIO_Error_Type check_sdio_status(Command_Index index = Command_Index::INVALID, bool check_index = false, bool ignore_crc = false);
+
+  // DMA configuration
+  void set_dma_parameters(uint8_t* buf, uint32_t count, bool is_write);
+
+  // SDIO configuration
+  void sdio_configure(const SDIO_Config config) { sdio_.init(config); }
+
+  // Varaible stored parameters
+  SDIO_Error_Type get_scr(uint16_t rca, uint32_t* scr);
+  SDIO_Error_Type store_cid();
+  SDIO_Error_Type store_csd();
+
+  // Accessor methods
+  SDIO_Config& get_config() { return config_; }
+  dma::DMA& get_dma_instance() { return dma_; }
+  void set_data_end_interrupt() { sdio_.set_interrupt_enable(Interrupt_Type::DTENDIE, true); }
+  void set_sdio_dma_enable(bool enable) { sdio_.set_dma_enable(enable); }
+  bool get_is_sdio_rx() { return is_rx_; }
+  void clear_sdio_data_flags() { sdio_.clear_multiple_interrupt_flags(clear_data_flags); }
+  void clear_sdio_cmd_flags() { sdio_.clear_multiple_interrupt_flags(clear_command_flags); }
+  void clear_sdio_common_flags() { sdio_.clear_multiple_interrupt_flags(clear_common_flags); }
+  Operational_State get_state() { return current_state_; }
+  void set_state(Operational_State state) { current_state_ = state; }
+  void set_transfer_end(bool value) { transfer_end_ = value; }
+  void set_transfer_error(SDIO_Error_Type error) { transfer_error_ = error; }
+
+  inline SDIO_Error_Type set_desired_clock(uint32_t desired_clock, bool wide_bus, bool low_power) {
+    sdio_.init({
+      desired_clock,
+      Clock_Edge::RISING_EDGE,
+      wide_bus ? Bus_Width::WIDTH_4BIT : Bus_Width::WIDTH_1BIT,
+      false,
+      low_power,
+      false
+    });
+    sync_domains();
+    desired_clock_ = desired_clock;
+
+    return SDIO_Error_Type::OK;
+  }
+
+private:
+  CardDMA();
+
+  // Prevent copying or assigning
+  CardDMA(const CardDMA&) = delete;
+  CardDMA& operator=(const CardDMA&) = delete;
+
+  // Helper function
+  SDIO_Error_Type wait_for_card_ready();
+
+  // Member variables
+  alignas(4) uint32_t sdcard_csd_[4];
+  alignas(4) uint32_t sdcard_cid_[4];
+  alignas(4) uint32_t sdcard_scr_[2];
+  uint32_t desired_clock_;
+  uint32_t stop_condition_;
+  uint32_t total_bytes_;
+  uint32_t count_;
+  SDIO& sdio_;
+  SDIO_Config& config_;
+  const dma::DMA_Base dmaBase_;
+  const dma::DMA_Channel dmaChannel_;
+  dma::DMA& dma_;
+  uint16_t sdcard_rca_;
+  SDIO_Error_Type transfer_error_;
+  Interface_Version interface_version_;
+  Card_Type card_type_;
+  volatile bool transfer_end_;
+  volatile bool is_rx_;
+  volatile bool multiblock_;
+  volatile Operational_State current_state_;
+
+  // Private helper methods
+  SDIO_Error_Type validate_voltage();
+  SDIO_Error_Type get_r1_result(Command_Index index);
+  //SDIO_Error_Type get_r2_r3_result();
+  SDIO_Error_Type get_r6_result(Command_Index index, uint16_t* rca);
+  SDIO_Error_Type get_r7_result();
+  //SDIO_Error_Type get_r1_error_type(uint32_t response);
+  SDIO_Error_Type get_command_sent_result();
+
+  inline void sync_domains() {
+    delayMicroseconds(8);
+  }
+
+  inline bool validate_transfer_params(uint32_t* buf, uint16_t size) {
+    if (buf == nullptr) return false;
+    // Size must be > 0, <= 2048 and power of 2
+    if ((size == 0U) || (size > 2048U) || (size & (size - 1U))) {
+      return false;
+    }
+    return true;
+  }
+
+  void process_sdsc_specific_csd(Card_Info* info, const uint8_t* csd_bytes) {
+    info->csd.device_size = (static_cast<uint32_t>(csd_bytes[6] & 0x03U) << 10U) |
+                 (static_cast<uint32_t>(csd_bytes[7]) << 2U) |
+                 (static_cast<uint32_t>((csd_bytes[8] & 0xC0U) >> 6U));
+    info->csd.device_size_multiplier = static_cast<uint8_t>((csd_bytes[9] & 0x03U) << 1U | 
+                                 (csd_bytes[10] & 0x80U) >> 7U);
+
+    info->block_size = static_cast<uint32_t>(1 << info->csd.read_block_length);
+    info->capacity = static_cast<uint32_t>((info->csd.device_size + 1U) * 
+            (1U << (info->csd.device_size_multiplier + 2U)) * 
+            info->block_size);
+  }
+
+  void process_sdhc_specific_csd(Card_Info* info, const uint8_t* csd_bytes) {
+    info->csd.device_size = static_cast<uint32_t>((csd_bytes[7] & 0x3FU) << 16U) |
+                 static_cast<uint32_t>((csd_bytes[8]) << 8U) |
+                 static_cast<uint32_t>(csd_bytes[9]);
+
+    info->block_size = BLOCK_SIZE;
+    info->capacity = static_cast<uint32_t>((info->csd.device_size + 1U) * 
+            BLOCK_SIZE * KILOBYTE);
+  }
+
+  void process_common_csd_tail(Card_Info* info, const uint8_t* csd_bytes) {
+    info->csd.sector_size = static_cast<uint8_t>(((csd_bytes[9] & 0x3FU) << 1U) | 
+                          (csd_bytes[10] & 0x80U) >> 7U);
+    info->csd.speed_factor = static_cast<uint8_t>((csd_bytes[11] & 0x1CU) >> 2U);
+    info->csd.write_block_length = static_cast<uint8_t>(((csd_bytes[11] & 0x03U) << 2U) | 
+                              ((csd_bytes[12] & 0xC0U) >> 6U));
+    info->csd.checksum = static_cast<uint8_t>((csd_bytes[15] & 0xFEU) >> 1U);
+  }
+
+  inline void disable_all_interrupts() {
+    sdio_.set_interrupt_enable(Interrupt_Type::DTCRCERRIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::DTTMOUTIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::DTENDIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::STBITEIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::TFHIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::RFHIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::TXUREIE, false);
+    sdio_.set_interrupt_enable(Interrupt_Type::RXOREIE, false);
+  }
+
+  template <typename CheckFunc>
+  inline SDIO_Error_Type send_command_and_check(Command_Index command, uint32_t argument,
+           Command_Response response, Wait_Type type, CheckFunc check_result) {
+    sdio_.set_command_state_machine(command, argument, response, type);
+    sync_domains();
+    sdio_.set_command_state_machine_enable(true);
+    return check_result();
+  }
+};
+
+} // namespace sdio
+
+extern sdio::CardDMA& CardDMA_I;

Marlin/src/HAL/GD32_MFL/Servo.cpp

@@ -0,0 +1,122 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#if HAS_SERVOS
+
+#include "Servo.h"
+
+static uint_fast8_t servoCount = 0;
+static libServo* servos[NUM_SERVOS] = {0};
+constexpr millis_t servoDelay[] = SERVO_DELAY;
+static_assert(COUNT(servoDelay) == NUM_SERVOS, "SERVO_DELAY must be an array NUM_SERVOS long.");
+
+// Initialize to the default timer priority. This will be overridden by a call from timers.cpp.
+// This allows all timer interrupt priorities to be managed from a single location in the HAL.
+static uint32_t servo_interrupt_priority = NVIC_EncodePriority(NVIC_GetPriorityGrouping(), 12, 0);
+
+// This must be called after the MFL Servo class has initialized the timer.
+// To be safe this is currently called after every call to attach().
+static void fixServoTimerInterruptPriority() {
+  NVIC_SetPriority(getTimerUpIRQ(TIMER_SERVO), servo_interrupt_priority);
+}
+
+// Default constructor for libServo class.
+// Initializes the servo delay, pause state, and pause value.
+// Registers the servo instance in the servos array.
+libServo::libServo() : delay(servoDelay[servoCount]),
+  was_attached_before_pause(false),
+  value_before_pause(0) {
+  servos[servoCount++] = this;
+}
+
+// Attaches a servo to a specified pin.
+int8_t libServo::attach(const int pin) {
+  if (servoCount >= MAX_SERVOS) return -1;
+  if (pin > 0) servo_pin = pin;
+  auto result = mflServo.attach(servo_pin);
+  fixServoTimerInterruptPriority();
+  return result;
+}
+
+// Attaches a servo to a specified pin with minimum and maximum pulse widths.
+int8_t libServo::attach(const int pin, const int min, const int max) {
+  if (servoCount >= MAX_SERVOS) return -1;
+  if (pin > 0) servo_pin = pin;
+  auto result = mflServo.attach(servo_pin, min, max);
+  fixServoTimerInterruptPriority();
+  return result;
+}
+
+// Moves the servo to a specified position.
+void libServo::move(const int value) {
+  if (attach(0) >= 0) {
+    mflServo.write(value);
+    safe_delay(delay);
+    TERN_(DEACTIVATE_SERVOS_AFTER_MOVE, detach());
+  }
+}
+
+// Pause the servo by detaching it and storing its current state.
+void libServo::pause() {
+  was_attached_before_pause = mflServo.attached();
+  if (was_attached_before_pause) {
+    value_before_pause = mflServo.read();
+    mflServo.detach();
+  }
+}
+
+// Resume a previously paused servo.
+// If the servo was attached before the pause, this function re-attaches
+// the servo and moves it to the position it was in before the pause.
+void libServo::resume() {
+  if (was_attached_before_pause) {
+    attach();
+    move(value_before_pause);
+  }
+}
+
+// Pause all servos by stopping their timers.
+void libServo::pause_all_servos() {
+  for (auto& servo : servos)
+    if (servo) servo->pause();
+}
+
+// Resume all paused servos by starting their timers.
+void libServo::resume_all_servos() {
+  for (auto& servo : servos)
+    if (servo) servo->resume();
+}
+
+// Set the interrupt priority for the servo.
+// @param preemptPriority The preempt priority level.
+// @param subPriority The sub priority level.
+void libServo::setInterruptPriority(uint32_t preemptPriority, uint32_t subPriority) {
+  servo_interrupt_priority = NVIC_EncodePriority(NVIC_GetPriorityGrouping(), preemptPriority, subPriority);
+}
+
+#endif // HAS_SERVOS
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/Servo.h

@@ -0,0 +1,56 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include <Servo.h>
+
+#include "../../core/millis_t.h"
+
+// Inherit and expand on the official library
+class libServo {
+public:
+  libServo();
+
+  int8_t attach(const int pin = 0); // pin == 0 uses value from previous call
+  int8_t attach(const int pin, const int min, const int max);
+  void detach() { mflServo.detach(); }
+
+  int read() { return mflServo.read(); }
+  void move(const int value);
+
+  void pause();
+  void resume();
+
+  static void pause_all_servos();
+  static void resume_all_servos();
+
+  static void setInterruptPriority(uint32_t preemptPriority, uint32_t subPriority);
+
+private:
+  Servo mflServo;
+
+  int servoPin = 0;
+  millis_t delay = 0;
+
+  bool was_attached_before_pause;
+  int value_before_pause;
+};

Marlin/src/HAL/GD32_MFL/dogm/u8g_com_mfl_swspi.cpp

@@ -0,0 +1,129 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm / Ryan Power
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../../inc/MarlinConfig.h"
+
+#if ALL(HAS_MARLINUI_U8GLIB, FORCE_SOFT_SPI)
+
+#include <U8glib-HAL.h>
+#include "../../shared/HAL_SPI.h"
+
+#define nop asm volatile ("\tnop\n")
+
+static inline uint8_t swSpiTransfer_mode_0(uint8_t b) {
+  for (uint8_t i = 0; i < 8; ++i) {
+    const uint8_t state = (b & 0x80) ? HIGH : LOW;
+    WRITE(DOGLCD_SCK, HIGH);
+    WRITE(DOGLCD_MOSI, state);
+    b <<= 1;
+    WRITE(DOGLCD_SCK, LOW);
+  }
+  return b;
+}
+
+static inline uint8_t swSpiTransfer_mode_3(uint8_t b) {
+  for (uint8_t i = 0; i < 8; ++i) {
+    const uint8_t state = (b & 0x80) ? HIGH : LOW;
+    WRITE(DOGLCD_SCK, LOW);
+    WRITE(DOGLCD_MOSI, state);
+    b <<= 1;
+    WRITE(DOGLCD_SCK, HIGH);
+  }
+  return b;
+}
+
+static void u8g_sw_spi_shift_out(uint8_t val) {
+  #if U8G_SPI_USE_MODE_3
+    swSpiTransfer_mode_3(val);
+  #else
+    swSpiTransfer_mode_0(val);
+  #endif
+}
+
+static void swSpiInit() {
+  #if PIN_EXISTS(LCD_RESET)
+    SET_OUTPUT(LCD_RESET_PIN);
+  #endif
+  SET_OUTPUT(DOGLCD_A0);
+  OUT_WRITE(DOGLCD_SCK, LOW);
+  OUT_WRITE(DOGLCD_MOSI, LOW);
+  OUT_WRITE(DOGLCD_CS, HIGH);
+}
+
+uint8_t u8g_com_HAL_MFL_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr) {
+  switch (msg) {
+    case U8G_COM_MSG_INIT:
+      swSpiInit();
+      break;
+    case U8G_COM_MSG_STOP:
+      break;
+    case U8G_COM_MSG_RESET:
+      #if PIN_EXISTS(LCD_RESET)
+        WRITE(LCD_RESET_PIN, arg_val);
+      #endif
+      break;
+    case U8G_COM_MSG_CHIP_SELECT:
+      #if U8G_SPI_USE_MODE_3        // This LCD SPI is running mode 3 while SD card is running mode 0
+        if (arg_val) {              // SCK idle state needs to be set to the proper idle state before
+                                    // the next chip select goes active
+          WRITE(DOGLCD_SCK, HIGH);  // Set SCK to mode 3 idle state before CS goes active
+          WRITE(DOGLCD_CS, LOW);
+          nop;                      // Hold SCK high for a few ns
+          nop;
+         }
+        else {
+          WRITE(DOGLCD_CS, HIGH);
+          WRITE(DOGLCD_SCK, LOW);   // Set SCK to mode 0 idle state after CS goes inactive
+        }
+      #else
+        WRITE(DOGLCD_CS, !arg_val);
+      #endif
+      break;
+    case U8G_COM_MSG_WRITE_BYTE:
+      u8g_sw_spi_shift_out(arg_val);
+      break;
+    case U8G_COM_MSG_WRITE_SEQ: {
+      uint8_t* ptr = (uint8_t*)arg_ptr;
+      while (arg_val > 0) {
+        u8g_sw_spi_shift_out(*ptr++);
+        arg_val--;
+      }
+    } break;
+    case U8G_COM_MSG_WRITE_SEQ_P: {
+      uint8_t* ptr = (uint8_t*)arg_ptr;
+      while (arg_val > 0) {
+        u8g_sw_spi_shift_out(u8g_pgm_read(ptr));
+        ptr++;
+        arg_val--;
+      }
+    } break;
+    case U8G_COM_MSG_ADDRESS:       // Define cmd (arg_val = 0) or data mode (arg_val = 1)
+      WRITE(DOGLCD_A0, arg_val);
+      break;
+  }
+  return 1;
+}
+
+#endif // HAS_MARLINUI_U8GLIB && FORCE_SOFT_SPI
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/eeprom_bl24cxx.cpp

@@ -0,0 +1,93 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * PersistentStore for Arduino-style EEPROM interface
+ * with simple implementations supplied by Marlin.
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(IIC_BL24CXX_EEPROM)
+
+#include "../shared/eeprom_if.h"
+#include "../shared/eeprom_api.h"
+
+#ifndef MARLIN_EEPROM_SIZE
+  #error "MARLIN_EEPROM_SIZE is required for IIC_BL24CXX_EEPROM."
+#endif
+
+size_t PersistentStore::capacity() {
+  return MARLIN_EEPROM_SIZE - eeprom_exclude_size;
+}
+
+bool PersistentStore::access_start() {
+  eeprom_init();
+  return true;
+}
+
+bool PersistentStore::access_finish() {
+  return true;
+}
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
+  while (size--) {
+    uint8_t v = *value;
+    uint8_t * const p = (uint8_t * const)REAL_EEPROM_ADDR(pos);
+    // EPROM has only ~100,000 write cycles,
+    // so only write bytes that have changed!
+    if (v != eeprom_read_byte(p)) {
+      eeprom_write_byte(p, v);
+      if (++written & 0x7F) delay(4); else safe_delay(4);
+      if (eeprom_read_byte(p) != v) {
+        SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
+        return true;
+      }
+    }
+
+    crc16(crc, &v, 1);
+    pos++;
+    value++;
+  }
+
+  return false;
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  do {
+    const uint8_t c = eeprom_read_byte((uint8_t*)REAL_EEPROM_ADDR(pos));
+    if (writing) *value = c;
+    crc16(crc, &c, 1);
+    pos++;
+    value++;
+  } while (--size);
+
+  return false;
+}
+
+#endif // IIC_BL24CXX_EEPROM
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/eeprom_if_iic.cpp

@@ -0,0 +1,54 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+/**
+ * Platform-independent Arduino functions for I2C EEPROM.
+ * Enable USE_SHARED_EEPROM if not supplied by the framework.
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(IIC_BL24CXX_EEPROM)
+
+#include "../../libs/BL24CXX.h"
+#include "../shared/eeprom_if.h"
+
+void eeprom_init() {
+  BL24CXX::init();
+}
+
+void eeprom_write_byte(uint8_t *pos, uint8_t value) {
+  const unsigned eeprom_address = (unsigned)pos;
+  return BL24CXX::writeOneByte(eeprom_address, value);
+}
+
+uint8_t eeprom_read_byte(uint8_t *pos) {
+  const unsigned eeprom_address = (unsigned)pos;
+  return BL24CXX::readOneByte(eeprom_address);
+}
+
+#endif // IIC_BL24CXX_EEPROM
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/eeprom_wired.cpp

@@ -0,0 +1,96 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#if USE_WIRED_EEPROM
+
+/**
+ * PersistentStore for Arduino-style EEPROM interface
+ * with simple implementations supplied by Marlin.
+ */
+
+#include "../shared/eeprom_if.h"
+#include "../shared/eeprom_api.h"
+
+#ifndef MARLIN_EEPROM_SIZE
+  #define MARLIN_EEPROM_SIZE size_t(E2END + 1)
+#endif
+
+size_t PersistentStore::capacity() {
+  return MARLIN_EEPROM_SIZE - eeprom_exclude_size;
+}
+
+bool PersistentStore::access_start() {
+  eeprom_init();
+  return true;
+}
+
+bool PersistentStore::access_finish() {
+  return true;
+}
+
+bool PersistentStore::write_data(int &pos, const uint8_t *value, size_t size, uint16_t *crc) {
+  uint16_t written = 0;
+  while (size--) {
+    uint8_t v = *value;
+    uint8_t * const p = (uint8_t * const)REAL_EEPROM_ADDR(pos);
+    // EEPROM has only ~100,000 write cycles,
+    // so only write bytes that have changed!
+    if (v != eeprom_read_byte(p)) {
+      eeprom_write_byte(p, v);
+      // Avoid triggering watchdog during long EEPROM writes
+      if (++written & 0x7F)
+        delay(2);
+      else
+        safe_delay(2);
+      if (eeprom_read_byte(p) != v) {
+        SERIAL_ECHO_MSG(STR_ERR_EEPROM_WRITE);
+        return true;
+      }
+    }
+    crc16(crc, &v, 1);
+    pos++;
+    value++;
+  }
+
+  return false;
+}
+
+bool PersistentStore::read_data(int &pos, uint8_t *value, size_t size, uint16_t *crc, const bool writing/*=true*/) {
+  do {
+    const uint8_t c = eeprom_read_byte((uint8_t*)REAL_EEPROM_ADDR(pos));
+    if (writing)
+      *value = c;
+    crc16(crc, &c, 1);
+    pos++;
+    value++;
+  } while (--size);
+
+  return false;
+}
+
+#endif // USE_WIRED_EEPROM
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/endstop_interrupts.h

@@ -0,0 +1,61 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../module/endstops.h"
+
+// One ISR for all EXT-Interrupts
+void endstop_ISR() { endstops.update(); }
+
+void setup_endstop_interrupts() {
+  #define _ATTACH(P) attachInterrupt(P, endstop_ISR, CHANGE)
+  TERN_(USE_X_MAX,       _ATTACH(X_MAX_PIN));
+  TERN_(USE_X_MIN,       _ATTACH(X_MIN_PIN));
+  TERN_(USE_Y_MAX,       _ATTACH(Y_MAX_PIN));
+  TERN_(USE_Y_MIN,       _ATTACH(Y_MIN_PIN));
+  TERN_(USE_Z_MAX,       _ATTACH(Z_MAX_PIN));
+  TERN_(USE_Z_MIN,       _ATTACH(Z_MIN_PIN));
+  TERN_(USE_X2_MAX,      _ATTACH(X2_MAX_PIN));
+  TERN_(USE_X2_MIN,      _ATTACH(X2_MIN_PIN));
+  TERN_(USE_Y2_MAX,      _ATTACH(Y2_MAX_PIN));
+  TERN_(USE_Y2_MIN,      _ATTACH(Y2_MIN_PIN));
+  TERN_(USE_Z2_MAX,      _ATTACH(Z2_MAX_PIN));
+  TERN_(USE_Z2_MIN,      _ATTACH(Z2_MIN_PIN));
+  TERN_(USE_Z3_MAX,      _ATTACH(Z3_MAX_PIN));
+  TERN_(USE_Z3_MIN,      _ATTACH(Z3_MIN_PIN));
+  TERN_(USE_Z4_MAX,      _ATTACH(Z4_MAX_PIN));
+  TERN_(USE_Z4_MIN,      _ATTACH(Z4_MIN_PIN));
+  TERN_(USE_Z_MIN_PROBE, _ATTACH(Z_MIN_PROBE_PIN));
+  TERN_(USE_CALIBRATION, _ATTACH(CALIBRATION_PIN));
+  TERN_(USE_I_MAX,       _ATTACH(I_MAX_PIN));
+  TERN_(USE_I_MIN,       _ATTACH(I_MIN_PIN));
+  TERN_(USE_J_MAX,       _ATTACH(J_MAX_PIN));
+  TERN_(USE_J_MIN,       _ATTACH(J_MIN_PIN));
+  TERN_(USE_K_MAX,       _ATTACH(K_MAX_PIN));
+  TERN_(USE_K_MIN,       _ATTACH(K_MIN_PIN));
+  TERN_(USE_U_MAX,       _ATTACH(U_MAX_PIN));
+  TERN_(USE_U_MIN,       _ATTACH(U_MIN_PIN));
+  TERN_(USE_V_MAX,       _ATTACH(V_MAX_PIN));
+  TERN_(USE_V_MIN,       _ATTACH(V_MIN_PIN));
+  TERN_(USE_W_MAX,       _ATTACH(W_MAX_PIN));
+  TERN_(USE_W_MIN,       _ATTACH(W_MIN_PIN));
+}

Marlin/src/HAL/GD32_MFL/fast_pwm.cpp

@@ -0,0 +1,97 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#include <PinOpsMap.hpp>
+#include <PinOps.hpp>
+#include "timers.h"
+
+static uint16_t timer_frequency[TIMER_COUNT];
+
+void MarlinHAL::set_pwm_duty(const pin_t pin, const uint16_t value, const uint16_t scale, const bool invert) {
+  // Calculate duty cycle based on inversion flag
+  const uint16_t duty = invert ? scale - value : value;
+
+  // Check if the pin supports PWM
+  if (PWM_PIN(pin)) {
+    // Get the timer peripheral base associated with the pin
+    const auto timer_base = getPinOpsPeripheralBase<TIMERPinOps, timer::TIMER_Base>(TIMER_PinOps, static_cast<pin_size_t>(pin));
+
+    // Initialize the timer instance
+    auto& TimerInstance = GeneralTimer::get_instance(timer_base);
+
+    // Get channel and previous channel mode
+    const auto channel = getPackedPinChannel(getPackedPinOps(TIMER_PinOps, static_cast<pin_size_t>(pin)));
+    const InputOutputMode previous = TimerInstance.getChannelMode(channel);
+
+    if (timer_frequency[static_cast<size_t>(timer_base)] == 0) {
+      set_pwm_frequency(pin, PWM_FREQUENCY);
+    }
+
+    // Set the PWM duty cycle
+    TimerInstance.setCaptureCompare(channel, duty, CCFormat::B8);
+
+    // Configure pin as PWM output
+    pinOpsPinout(TIMER_PinOps, static_cast<pin_size_t>(pin));
+
+    // Set channel mode if not already set and start timer
+    if (previous != InputOutputMode::PWM0) {
+      TimerInstance.setChannelMode(channel, InputOutputMode::PWM0, static_cast<pin_size_t>(pin));
+      TimerInstance.start();
+    }
+  } else {
+    pinMode(pin, OUTPUT);
+    digitalWrite(pin, duty < scale / 2 ? LOW : HIGH);
+  }
+}
+
+void MarlinHAL::set_pwm_frequency(const pin_t pin, const uint16_t f_desired) {
+  // Check if the pin supports PWM
+  if (!PWM_PIN(pin)) return;
+
+  // Get the timer peripheral base associated with the pin
+  const auto timer_base = getPinOpsPeripheralBase<TIMERPinOps, timer::TIMER_Base>(TIMER_PinOps, static_cast<pin_size_t>(pin));
+
+  // Guard against modifying protected timers
+  #ifdef STEP_TIMER
+    if (timer_base == static_cast<timer::TIMER_Base>(STEP_TIMER)) return;
+  #endif
+  #ifdef TEMP_TIMER
+    if (timer_base == static_cast<timer::TIMER_Base>(TEMP_TIMER)) return;
+  #endif
+  #if defined(PULSE_TIMER) && MF_TIMER_PULSE != MF_TIMER_STEP
+    if (timer_base == static_cast<timer::TIMER_Base>(PULSE_TIMER)) return;
+  #endif
+
+  // Initialize the timer instance
+  auto& TimerInstance = GeneralTimer::get_instance(timer_base);
+
+  TimerInstance.setRolloverValue(f_desired, TimerFormat::HERTZ);
+  timer_frequency[timer_base_to_index(timer_base)] = f_desired;
+}
+
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/fastio.h

@@ -0,0 +1,82 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+// Fast I/O interfaces for GD32F303RE
+
+#include <GPIO.hpp>
+#include <PinOps.hpp>
+#include <PinOpsMap.hpp>
+
+static inline void fast_write_pin_wrapper(pin_size_t IO, bool V) {
+  if (V) gpio::fast_set_pin(getPortFromPin(IO), getPinInPort(IO));
+  else gpio::fast_clear_pin(getPortFromPin(IO), getPinInPort(IO));
+}
+
+static inline bool fast_read_pin_wrapper(pin_size_t IO) {
+  return gpio::fast_read_pin(getPortFromPin(IO), getPinInPort(IO));
+}
+
+static inline void fast_toggle_pin_wrapper(pin_size_t IO) {
+  gpio::fast_toggle_pin(getPortFromPin(IO), getPinInPort(IO));
+}
+
+// ------------------------
+// Defines
+// ------------------------
+
+#ifndef PWM
+  #define PWM OUTPUT
+#endif
+
+#define _WRITE(IO, V)           fast_write_pin_wrapper(IO, V)
+#define _READ(IO)               fast_read_pin_wrapper(IO)
+#define _TOGGLE(IO)             fast_toggle_pin_wrapper(IO)
+
+#define _GET_MODE(IO)
+#define _SET_MODE(IO, M)        pinMode((IO), (M))
+#define _SET_OUTPUT(IO)         pinMode((IO), OUTPUT)
+#define _SET_OUTPUT_OD(IO)      pinMode((IO), OUTPUT_OPEN_DRAIN)
+
+#define WRITE(IO, V)            _WRITE((IO), (V))
+#define READ(IO)                _READ(IO)
+#define TOGGLE(IO)              _TOGGLE(IO)
+
+#define OUT_WRITE(IO, V)        do { _SET_OUTPUT(IO); WRITE((IO), (V)); } while (0)
+#define OUT_WRITE_OD(IO, V)     do { _SET_OUTPUT_OD(IO); WRITE((IO), (V)); } while (0)
+
+#define SET_INPUT(IO)           _SET_MODE((IO), INPUT)
+#define SET_INPUT_PULLUP(IO)    _SET_MODE((IO), INPUT_PULLUP)
+#define SET_INPUT_PULLDOWN(IO)  _SET_MODE((IO), INPUT_PULLDOWN)
+#define SET_OUTPUT(IO)          OUT_WRITE((IO), LOW)
+#define SET_OUTPUT_OD(IO)       OUT_WRITE_OD((IO), LOW)
+#define SET_PWM(IO)             _SET_MODE((IO), PWM)
+
+#define IS_INPUT(IO)
+#define IS_OUTPUT(IO)
+
+#define PWM_PIN(P)              isPinInPinOps(TIMER_PinOps, P)
+#define NO_COMPILE_TIME_PWM
+
+// Wrappers for digitalRead and digitalWrite
+#define extDigitalRead(IO)      digitalRead(IO)
+#define extDigitalWrite(IO, V)  digitalWrite((IO), (V))

Marlin/src/HAL/GD32_MFL/inc/Conditionals_LCD.h

@@ -0,0 +1,26 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#if ALL(HAS_MARLINUI_U8GLIB, FORCE_SOFT_SPI)
+  #define U8G_SW_SPI_MFL 1
+#endif

Marlin/src/HAL/GD32_MFL/inc/Conditionals_adv.h

@@ -0,0 +1,26 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#if ALL(HAS_MEDIA, USBD_USE_CDC_MSC)
+  #define HAS_SD_HOST_DRIVE 1
+#endif

Marlin/src/HAL/GD32_MFL/inc/Conditionals_post.h

@@ -0,0 +1,29 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+// If no real or emulated EEPROM selected, fall back to SD emulation
+#if USE_FALLBACK_EEPROM
+  #define SDCARD_EEPROM_EMULATION
+#elif ANY(I2C_EEPROM, SPI_EEPROM)
+  #define USE_SHARED_EEPROM 1
+#endif

Marlin/src/HAL/GD32_MFL/inc/Conditionals_type.h

@@ -0,0 +1,22 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once

Marlin/src/HAL/GD32_MFL/inc/SanityCheck.h

@@ -0,0 +1,97 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+// Test MFL GD32 specific configuration values for errors at compile-time.
+#if ENABLED(SDCARD_EEPROM_EMULATION) && !HAS_MEDIA
+  #undef SDCARD_EEPROM_EMULATION  // avoid additional error noise
+  #if USE_FALLBACK_EEPROM
+    #warning "EEPROM type not specified. Fallback is SDCARD_EEPROM_EMULATION."
+  #endif
+  #error "SDCARD_EEPROM_EMULATION requires SDSUPPORT. Enable SDSUPPORT or choose another EEPROM emulation."
+#endif
+
+#if ENABLED(FLASH_EEPROM_LEVELING)
+  #error "FLASH_EEPROM_LEVELING is not supported on GD32."
+#endif
+
+#if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
+  #error "SERIAL_STATS_MAX_RX_QUEUED is not supported on GD32."
+#elif ENABLED(SERIAL_STATS_DROPPED_RX)
+  #error "SERIAL_STATS_DROPPED_RX is not supported on GD32."
+#endif
+
+#if TEMP_SENSOR_SOC && defined(ATEMP) && TEMP_SOC_PIN != ATEMP
+  #error "TEMP_SENSOR_SOC requires 'TEMP_SOC_PIN ATEMP' on GD32"
+#endif
+
+// Check for common serial pin conflicts
+#define _CHECK_SERIAL_PIN(N) (( \
+    BTN_EN1 == N || BTN_EN2 == N || DOGLCD_CS == N || HEATER_BED_PIN == N || FAN0_PIN == N || \
+    SDIO_D2_PIN == N || SDIO_D3_PIN == N || SDIO_CK_PIN == N || SDIO_CMD_PIN == N || \
+    Y_STEP_PIN == N || Y_ENABLE_PIN == N || E0_ENABLE_PIN == N || POWER_LOSS_PIN == N \
+  ))
+
+#define CHECK_SERIAL_PIN(T, N) defined(UART##N##_##T##_PIN) && _CHECK_SERIAL_PIN(UART##N##_##T##_PIN)
+
+#if SERIAL_IN_USE(0)
+  #if CHECK_SERIAL_PIN(TX, 0)
+    #error "Serial Port 0 TX IO pins conflict with another pin on the board."
+  #endif
+  #if CHECK_SERIAL_PIN(RX, 0)
+    #error "Serial Port 0 RX IO pins conflict with another pin on the board."
+  #endif
+#endif
+#if SERIAL_IN_USE(1)
+  #if CHECK_SERIAL_PIN(TX, 1)
+    #error "Serial Port 1 TX IO pins conflict with another pin on the board."
+  #endif
+  #if CHECK_SERIAL_PIN(RX, 1)
+    #error "Serial Port 1 RX IO pins conflict with another pin on the board."
+  #endif
+#endif
+#if SERIAL_IN_USE(2)
+  #if CHECK_SERIAL_PIN(TX, 2)
+    #error "Serial Port 2 TX IO pins conflict with another pin on the board."
+  #endif
+  #if CHECK_SERIAL_PIN(RX, 2)
+    #error "Serial Port 2 RX IO pins conflict with another pin on the board."
+  #endif
+#endif
+#if SERIAL_IN_USE(3)
+  #if CHECK_SERIAL_PIN(TX, 3)
+    #error "Serial Port 3 TX IO pins conflict with another pin on the board."
+  #endif
+  #if CHECK_SERIAL_PIN(RX, 3)
+    #error "Serial Port 3 RX IO pins conflict with another pin on the board."
+  #endif
+#endif
+#if SERIAL_IN_USE(4)
+  #if CHECK_SERIAL_PIN(TX, 4)
+    #error "Serial Port 4 TX IO pins conflict with another pin on the board."
+  #endif
+  #if CHECK_SERIAL_PIN(RX, 4)
+    #error "Serial Port 4 RX IO pins conflict with another pin on the board."
+  #endif
+#endif
+#undef CHECK_SERIAL_PIN
+#undef _CHECK_SERIAL_PIN

Marlin/src/HAL/GD32_MFL/pinsDebug.h

@@ -0,0 +1,102 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * Pins Debugging for GD32
+ *
+ *   - NUMBER_PINS_TOTAL
+ *   - MULTI_NAME_PAD
+ *   - getPinByIndex(index)
+ *   - printPinNameByIndex(index)
+ *   - getPinIsDigitalByIndex(index)
+ *   - digitalPinToAnalogIndex(pin)
+ *   - getValidPinMode(pin)
+ *   - isValidPin(pin)
+ *   - isAnalogPin(pin)
+ *   - digitalRead_mod(pin)
+ *   - pwm_status(pin)
+ *   - printPinPWM(pin)
+ *   - printPinPort(pin)
+ *   - printPinNumber(pin)
+ *   - printPinAnalog(pin)
+ */
+
+#include "../../inc/MarlinConfig.h"
+#include <Arduino.h>
+#include <PinOps.hpp>
+#include <Analog.h>
+
+#ifndef TOTAL_PIN_COUNT
+  #error "Expected TOTAL_PIN_COUNT not found."
+#endif
+
+#define NUM_DIGITAL_PINS  TOTAL_PIN_COUNT
+#define NUMBER_PINS_TOTAL TOTAL_PIN_COUNT
+
+#define getPinByIndex(x) pin_t(pin_array[x].pin)
+#define isValidPin(P) WITHIN(P, 0, (NUM_DIGITAL_PINS - 1))
+#define digitalRead_mod(P) extDigitalRead(P)
+#define printPinNumber(P) do { sprintf_P(buffer, PSTR("%3hd "), pin_t(P)); SERIAL_ECHO(buffer); } while (0)
+#define printPinAnalog(P) do { sprintf_P(buffer, PSTR(" (A%2d)  "), pin_t(getAdcChannelFromPin(P))); SERIAL_ECHO(buffer); } while (0)
+#define printPinNameByIndex(x) do { sprintf_P(buffer, PSTR("%-" STRINGIFY(MAX_NAME_LENGTH) "s"), pin_array[x].name); SERIAL_ECHO(buffer); } while (0)
+
+#define MULTI_NAME_PAD 21 // Space needed to be pretty if not first name assigned to a pin
+
+#ifndef M43_NEVER_TOUCH
+  #define M43_NEVER_TOUCH(x) WITHIN(x, 9, 10) // SERIAL pins: PA9(TX) PA10(RX)
+#endif
+
+bool isAnalogPin(const pin_t pin) {
+  if (!isValidPin(pin)) return false;
+
+  if (getAdcChannel(pin) != adc::ADC_Channel::INVALID) {
+    auto& instance = gpio::GPIO::get_instance(getPortFromPin(pin)).value();
+    return instance.get_pin_mode(getPinInPort(pin)) == gpio::Pin_Mode::ANALOG && !M43_NEVER_TOUCH(pin);
+  }
+
+  return false;
+}
+
+bool getValidPinMode(const pin_t pin) {
+  if (!isValidPin(pin)) return false;
+
+  auto& instance = gpio::GPIO::get_instance(getPortFromPin(pin)).value();
+  gpio::Pin_Mode mode = instance.get_pin_mode(getPinInPort(pin));
+
+  return mode != gpio::Pin_Mode::ANALOG && mode != gpio::Pin_Mode::INPUT_FLOATING &&
+         mode != gpio::Pin_Mode::INPUT_PULLUP && mode != gpio::Pin_Mode::INPUT_PULLDOWN;
+}
+
+bool getPinIsDigitalByIndex(const int16_t index) {
+  const pin_t pin = getPinByIndex(index);
+  return (!isAnalogPin(pin));
+}
+
+int8_t digitalPinToAnalogIndex(const pin_t pin) {
+  if (!isValidPin(pin) || !isAnalogPin(pin)) return -1;
+  return pin; // Analog and digital pin indexes are shared
+}
+
+bool pwm_status(const pin_t pin) { return false; }
+void printPinPWM(const pin_t pin) { /* TODO */ }
+void printPinPort(const pin_t pin) { /* TODO */ }

Marlin/src/HAL/GD32_MFL/sdio.cpp

@@ -0,0 +1,233 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+
+#if ENABLED(ONBOARD_SDIO)
+
+#include <PinOpsMap.hpp>
+#include <PinOps.hpp>
+#include "SDCard.h"
+#include "sdio.h"
+
+using namespace sdio;
+
+#define TARGET_CLOCK  6000000U
+#define BLOCK_SIZE    512U
+#define CARD_TIMEOUT  500 // ms
+#define READ_RETRIES  3U
+
+inline constexpr uint32_t TARGET_SDIO_CLOCK = TARGET_CLOCK;
+inline constexpr uint32_t SDIO_BLOCK_SIZE = BLOCK_SIZE;
+inline constexpr uint32_t SD_TIMEOUT = CARD_TIMEOUT;
+inline constexpr uint8_t SDIO_READ_RETRIES = READ_RETRIES;
+
+Card_State cardState = Card_State::READY;
+
+bool SDIO_SetBusWidth(Bus_Width width) {
+  return (CardDMA_I.set_hardware_bus_width(width) == SDIO_Error_Type::OK);
+}
+
+void mfl_sdio_init() {
+  pinOpsPinout(SD_CMD_PinOps, static_cast<pin_size_t>(SDIO_CMD_PIN));
+  pinOpsPinout(SD_CK_PinOps, static_cast<pin_size_t>(SDIO_CK_PIN));
+  pinOpsPinout(SD_DATA0_PinOps, static_cast<pin_size_t>(SDIO_D0_PIN));
+  pinOpsPinout(SD_DATA1_PinOps, static_cast<pin_size_t>(SDIO_D1_PIN));
+  pinOpsPinout(SD_DATA2_PinOps, static_cast<pin_size_t>(SDIO_D2_PIN));
+  pinOpsPinout(SD_DATA3_PinOps, static_cast<pin_size_t>(SDIO_D3_PIN));
+
+  NVIC_EnableIRQ(DMA1_Channel3_4_IRQn);
+  NVIC_EnableIRQ(SDIO_IRQn);
+}
+
+bool SDIO_Init() {
+  SDIO_Error_Type result = SDIO_Error_Type::OK;
+  uint8_t retryCount = SDIO_READ_RETRIES;
+
+  mfl_sdio_init();
+
+  uint8_t retries = retryCount;
+  for (;;) {
+    hal.watchdog_refresh();
+    result = CardDMA_I.init();
+    if (result == SDIO_Error_Type::OK) break;
+    if (!--retries) return false;
+  }
+
+  CardDMA_I.set_desired_clock(TARGET_SDIO_CLOCK, false, false);
+
+  retries = retryCount;
+  for (;;) {
+    hal.watchdog_refresh();
+    if (SDIO_SetBusWidth(Bus_Width::WIDTH_4BIT)) break;
+    if (!--retries) break;
+  }
+
+  CardDMA_I.set_desired_clock(TARGET_SDIO_CLOCK, true, true);
+
+  // Fallback
+  if (!retries) {
+    mfl_sdio_init();
+    retries = retryCount;
+    for (;;) {
+      hal.watchdog_refresh();
+      result = CardDMA_I.init();
+      if (result == SDIO_Error_Type::OK) break;
+      if (!--retries) return false;
+    }
+    CardDMA_I.set_desired_clock(TARGET_SDIO_CLOCK, false, true);
+  }
+
+  return true;
+}
+
+static bool SDIO_ReadWriteBlock_DMA(uint32_t block, const uint8_t* src, uint8_t* dst) {
+  hal.watchdog_refresh();
+  SDIO_Error_Type result = SDIO_Error_Type::OK;
+
+  // Write
+  if (src) {
+    result = CardDMA_I.write(reinterpret_cast<uint8_t*>(const_cast<uint8_t*>(src)), block, 1);
+  }
+  // Read
+  else {
+    result = CardDMA_I.read(dst, block, 1);
+  }
+
+  if (result != SDIO_Error_Type::OK) {
+    return false;
+  }
+
+  millis_t timeout = millis() + SD_TIMEOUT;
+  while (CardDMA_I.get_state() != sdio::Operational_State::READY) {
+    if (ELAPSED(millis(), timeout)) {
+      return false;
+    }
+  }
+
+  CardDMA_I.check_dma_complete();
+
+  timeout = millis() + SD_TIMEOUT;
+  do {
+    result = CardDMA_I.get_card_state(&cardState);
+    if (ELAPSED(millis(), timeout)) {
+      return false;
+    }
+  } while (result == SDIO_Error_Type::OK && cardState != sdio::Card_State::TRANSFER);
+
+  return true;
+}
+
+bool SDIO_ReadBlock(uint32_t block, uint8_t* dst) {
+  // Check if the address is aligned to 4 bytes
+  if (reinterpret_cast<uint32_t>(dst) & 0x03) {
+    return false;
+  }
+
+  uint8_t retries = SDIO_READ_RETRIES;
+  while (retries--) {
+    if (SDIO_ReadWriteBlock_DMA(block, nullptr, dst)) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+bool SDIO_WriteBlock(uint32_t block, const uint8_t* src) {
+  // Check if the address is aligned to 4 bytes
+  if (reinterpret_cast<uint32_t>(src) & 0x03) {
+    return false;
+  }
+
+  uint8_t retries = SDIO_READ_RETRIES;
+  while (retries--) {
+    if (SDIO_ReadWriteBlock_DMA(block, src, nullptr)) {
+      return true;
+      delay(10);
+    }
+  }
+
+  return false;
+}
+
+bool SDIO_IsReady() {
+  return (CardDMA_I.get_state() == sdio::Operational_State::READY);
+}
+
+uint32_t SDIO_GetCardSize() {
+  return CardDMA_I.get_card_capacity();
+}
+
+// DMA interrupt handler
+void DMA1_IRQHandler() {
+  auto& dma_instance = CardDMA_I.get_dma_instance();
+  bool is_receive = CardDMA_I.get_is_sdio_rx();
+
+  // Check for Transfer Complete Interrupt
+  if (dma_instance.get_interrupt_flag(dma::Interrupt_Flags::INTR_FLAG_FTFIF)) {
+    dma_instance.set_interrupt_enable(dma::Interrupt_Type::INTR_FTFIE, false);
+    dma_instance.set_interrupt_enable(dma::Interrupt_Type::INTR_ERRIE, false);
+    dma_instance.clear_interrupt_flag(dma::Interrupt_Flags::INTR_FLAG_FTFIF);
+    if (is_receive) {
+      CardDMA_I.set_sdio_dma_enable(false);
+      CardDMA_I.clear_sdio_data_flags();
+      CardDMA_I.set_state(sdio::Operational_State::READY);
+    } else {
+      CardDMA_I.set_data_end_interrupt();
+    }
+    // Signal that transfer is complete
+    CardDMA_I.set_transfer_end(true);
+  }
+
+  else if (dma_instance.get_interrupt_flag(dma::Interrupt_Flags::INTR_FLAG_ERRIF)) {
+    dma_instance.set_interrupt_enable(dma::Interrupt_Type::INTR_HTFIE, false);
+    dma_instance.set_interrupt_enable(dma::Interrupt_Type::INTR_ERRIE, false);
+    dma_instance.set_interrupt_enable(dma::Interrupt_Type::INTR_FTFIE, false);
+    // Clear all flags
+    dma_instance.clear_interrupt_flag(dma::Interrupt_Flags::INTR_FLAG_GIF);
+    // Signal that an error occurred
+    CardDMA_I.set_transfer_error(SDIO_Error_Type::ERROR);
+    CardDMA_I.set_state(sdio::Operational_State::READY);
+  }
+}
+
+
+extern "C" {
+
+  void SDIO_IRQHandler(void) {
+    CardDMA_I.handle_interrupts();
+  }
+
+  void DMA1_Channel3_4_IRQHandler(void) {
+    DMA1_IRQHandler();
+  }
+
+} // extern "C"
+
+
+#endif // ONBOARD_SDIO
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/sdio.h

@@ -0,0 +1,36 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include <SDIO.hpp>
+#include <DMA.hpp>
+
+#define SDIO_D0_PIN   PC8
+#define SDIO_D1_PIN   PC9
+#define SDIO_D2_PIN   PC10
+#define SDIO_D3_PIN   PC11
+#define SDIO_CK_PIN   PC12
+#define SDIO_CMD_PIN  PD2
+
+void sdio_mfl_init();
+bool SDIO_SetBusWidth(sdio::Bus_Width width);
+void DMA1_IRQHandler(dma::DMA_Channel channel);

Marlin/src/HAL/GD32_MFL/spi_pins.h

@@ -0,0 +1,32 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#pragma once
+
+// Define SPI Pins: SCK, MISO, MOSI
+#ifndef SD_SCK_PIN
+  #define SD_SCK_PIN  PIN_SPI_SCK
+#endif
+#ifndef SD_MISO_PIN
+  #define SD_MISO_PIN PIN_SPI_MISO
+#endif
+#ifndef SD_MOSI_PIN
+  #define SD_MOSI_PIN PIN_SPI_MOSI
+#endif

Marlin/src/HAL/GD32_MFL/temp_soc.h

@@ -0,0 +1,29 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#define TS_TYPICAL_V      1.405
+#define TS_TYPICAL_TEMP   25
+#define TS_TYPICAL_SLOPE  4.5
+
+// TODO: Implement voltage scaling (calibrated Vrefint) and ADC resolution scaling (when applicable)
+#define TEMP_SOC_SENSOR(RAW) ((TS_TYPICAL_V - (RAW) / float(OVERSAMPLENR) / float(HAL_ADC_RANGE) * (float(ADC_VREF_MV) / 1000)) / ((TS_TYPICAL_SLOPE) / 1000) + TS_TYPICAL_TEMP)

Marlin/src/HAL/GD32_MFL/timers.cpp

@@ -0,0 +1,233 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#include "../platforms.h"
+
+#ifdef ARDUINO_ARCH_MFL
+
+#include "../../inc/MarlinConfig.h"
+#include "timers.h"
+
+// ------------------------
+// Local defines
+// ------------------------
+
+#define SWSERIAL_TIMER_IRQ_PRIORITY_DEFAULT 1   // Requires tight bit timing to communicate reliably with TMC drivers
+#define SERVO_TIMER_IRQ_PRIORITY_DEFAULT    1   // Requires tight PWM timing to control a BLTouch reliably
+#define STEP_TIMER_IRQ_PRIORITY_DEFAULT     2
+#define TEMP_TIMER_IRQ_PRIORITY_DEFAULT     14  // Low priority avoids interference with other hardware and timers
+
+#ifndef TIMER_IRQ_PRIORITY
+  #define TIMER_IRQ_PRIORITY 12
+#endif
+
+#ifndef STEP_TIMER_IRQ_PRIORITY
+  #define STEP_TIMER_IRQ_PRIORITY STEP_TIMER_IRQ_PRIORITY_DEFAULT
+#endif
+
+#ifndef TEMP_TIMER_IRQ_PRIORITY
+  #define TEMP_TIMER_IRQ_PRIORITY TEMP_TIMER_IRQ_PRIORITY_DEFAULT
+#endif
+
+#if HAS_TMC_SW_SERIAL
+  #include <SoftwareSerial.h>
+  #ifndef SWSERIAL_TIMER_IRQ_PRIORITY
+    #define SWSERIAL_TIMER_IRQ_PRIORITY SWSERIAL_TIMER_IRQ_PRIORITY_DEFAULT
+  #endif
+#endif
+
+#if HAS_SERVOS
+  #include "Servo.h"
+  #ifndef SERVO_TIMER_IRQ_PRIORITY
+    #define SERVO_TIMER_IRQ_PRIORITY    SERVO_TIMER_IRQ_PRIORITY_DEFAULT
+  #endif
+#endif
+
+#if ENABLED(SPEAKER)
+  // The MFL framework default timer priority is 12. The TEMP timer must have lower priority
+  // than this due to the long running temperature ISR, and STEP timer should higher priority.
+  #if !(TIMER_IRQ_PRIORITY > STEP_TIMER_IRQ_PRIORITY && TIMER_IRQ_PRIORITY < TEMP_TIMER_IRQ_PRIORITY)
+    #error "Default timer interrupt priority is unspecified or set to a value which may degrade performance."
+  #endif
+#endif
+
+#ifndef HAL_TIMER_RATE
+  #define HAL_TIMER_RATE  GetStepperTimerClkFreq()
+#endif
+
+#ifndef STEP_TIMER
+  #define STEP_TIMER    MF_TIMER_STEP
+#endif
+#ifndef TEMP_TIMER
+  #define TEMP_TIMER    MF_TIMER_TEMP
+#endif
+
+GeneralTimer& Step_Timer = GeneralTimer::get_instance(static_cast<timer::TIMER_Base>(STEP_TIMER));
+GeneralTimer& Temp_Timer = GeneralTimer::get_instance(static_cast<timer::TIMER_Base>(TEMP_TIMER));
+
+bool is_step_timer_initialized = false;
+bool is_temp_timer_initialized = false;
+
+// ------------------------
+// Public functions
+// ------------------------
+
+// Retrieves the clock frequency of the stepper timer
+uint32_t GetStepperTimerClkFreq() {
+  return Step_Timer.getTimerClockFrequency();
+}
+
+/**
+ * @brief Starts a hardware timer
+ * 
+ * If the timer is not already initialized, this function will initialize it with the given frequency.
+ * The timer is started immediately after initialization
+ * 
+ * @param timer The timer base index to start
+ * @param frequency The frequency at which the timer should run
+ * @return None
+ */
+void HAL_timer_start(const uint8_t timer_number, const uint32_t frequency) {
+  if (HAL_timer_initialized(timer_number) || (timer_number != MF_TIMER_STEP && timer_number != MF_TIMER_TEMP))
+    return;
+
+  const bool is_step = (timer_number == MF_TIMER_STEP);
+  const uint8_t priority = is_step ?
+                           static_cast<uint8_t>(STEP_TIMER_IRQ_PRIORITY) :
+                           static_cast<uint8_t>(TEMP_TIMER_IRQ_PRIORITY);
+
+  // Get the reference of the timer instance
+  GeneralTimer& timer = is_step ? Step_Timer : Temp_Timer;
+
+  if (is_step) {
+    timer.setPrescaler(STEPPER_TIMER_PRESCALE);
+    timer.setRolloverValue(_MIN(static_cast<hal_timer_t>(HAL_TIMER_TYPE_MAX),
+                               (HAL_TIMER_RATE) / (STEPPER_TIMER_PRESCALE)),
+                               TimerFormat::TICK);
+    is_step_timer_initialized = true;
+  }
+  else {
+    timer.setRolloverValue(frequency, TimerFormat::HERTZ);
+    is_temp_timer_initialized = true;
+  }
+
+  timer.setAutoReloadEnable(false);
+  timer.setInterruptPriority(priority, 0U);
+  HAL_timer_enable_interrupt(timer_number);
+  timer.start();
+}
+
+/**
+ * @brief Enables the interrupt for the specified timer
+ * 
+ * @param handle The timer handle for which to enable the interrupt
+ * @return None
+ */
+void HAL_timer_enable_interrupt(const uint8_t timer_number) {
+  if (!HAL_timer_initialized(timer_number)) return;
+
+  GeneralTimer& timer = (timer_number == MF_TIMER_STEP) ? Step_Timer : Temp_Timer;
+
+  if (timer_number == MF_TIMER_STEP && !timer.hasInterrupt())
+    timer.attachInterrupt(Step_Handler);
+  else if (timer_number == MF_TIMER_TEMP && !timer.hasInterrupt())
+    timer.attachInterrupt(Temp_Handler);
+}
+
+/**
+ * @brief Disables the interrupt for the specified timer
+ * 
+ * @param handle The timer handle for which to disable the interrupt
+ * @return None
+ */
+void HAL_timer_disable_interrupt(const uint8_t timer_number) {
+  if (!HAL_timer_initialized(timer_number)) return;
+
+  GeneralTimer& timer = (timer_number == MF_TIMER_STEP) ? Step_Timer : Temp_Timer;
+  if (timer_number == MF_TIMER_STEP || timer_number == MF_TIMER_TEMP)
+    timer.detachInterrupt();
+}
+
+/**
+ * @brief Checks if the interrupt is enabled for the specified timer
+ * 
+ * @param handle The timer handle to check
+ * @return True if the interrupt is enabled, false otherwise
+ */
+bool HAL_timer_interrupt_enabled(const uint8_t timer_number) {
+  if (!HAL_timer_initialized(timer_number)) return false;
+
+  GeneralTimer& timer = (timer_number == MF_TIMER_STEP) ? Step_Timer : Temp_Timer;
+  return (timer_number == MF_TIMER_STEP || timer_number == MF_TIMER_TEMP)
+         ? timer.hasInterrupt()
+         : false;
+}
+
+// Sets the interrupt priorities for timers used by TMC SW serial and servos.
+void SetTimerInterruptPriorities() {
+  TERN_(HAS_TMC_SW_SERIAL, SoftwareSerial::setInterruptPriority(SWSERIAL_TIMER_IRQ_PRIORITY, 0));
+  TERN_(HAS_SERVOS, libServo::setInterruptPriority(SERVO_TIMER_IRQ_PRIORITY, 0));
+}
+
+// ------------------------
+// Detect timer conflicts
+// ------------------------
+
+TERN_(SPEAKER, static constexpr timer::TIMER_Base timer_tone[] = {static_cast<timer::TIMER_Base>(TIMER_TONE)});
+TERN_(HAS_SERVOS, static constexpr timer::TIMER_Base timer_servo[] = {static_cast<timer::TIMER_Base>(TIMER_SERVO)});
+
+enum TimerPurpose {
+  PURPOSE_TONE,
+  PURPOSE_SERVO,
+  PURPOSE_STEP,
+  PURPOSE_TEMP
+};
+
+// List of timers to check for conflicts
+// Includes the timer purpose to ease debugging when evaluating at build-time
+// This cannot yet account for timers used for PWM output, such as for fans
+static constexpr struct { TimerPurpose p; int t; } timers_in_use[] = {
+  #if ENABLED(SPEAKER)
+    { PURPOSE_TONE, timer_base_to_index(timer_tone[0]) },     // Set in variant.h
+  #endif
+  #if HAS_SERVOS
+    { PURPOSE_SERVO, timer_base_to_index(timer_servo[0]) },   // Set in variant.h
+  #endif
+  { PURPOSE_STEP, MF_TIMER_STEP },
+  { PURPOSE_TEMP, MF_TIMER_TEMP },
+};
+
+// Verifies if there are any timer conflicts in the timers_in_use array
+static constexpr bool verify_no_timer_conflicts() {
+  for (uint8_t i = 0; i < COUNT(timers_in_use); i++)
+    for (uint8_t j = i + 1; j < COUNT(timers_in_use); j++)
+      if (timers_in_use[i].t == timers_in_use[j].t)
+        return false;
+
+  return true;
+}
+
+// If this assertion fails at compile time, review the timers_in_use array.
+// If default_envs is defined properly in platformio.ini, VSCode can evaluate the array
+// when hovering over it, making it easy to identify the conflicting timers
+static_assert(verify_no_timer_conflicts(), "One or more timer conflict detected. Examine \"timers_in_use\" to help identify conflict.");
+
+#endif // ARDUINO_ARCH_MFL

Marlin/src/HAL/GD32_MFL/timers.h

@@ -0,0 +1,145 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+#include "../../inc/MarlinConfig.h"
+
+#include <GeneralTimer.h>
+
+// ------------------------
+// Defines
+// ------------------------
+
+// Timer configuration constants
+#define STEPPER_TIMER_RATE    2000000
+#define TEMP_TIMER_FREQUENCY  1000
+
+// Timer instance definitions
+#define MF_TIMER_STEP     3
+#define MF_TIMER_TEMP     1
+#define MF_TIMER_PULSE    MF_TIMER_STEP
+
+#define hal_timer_t         uint32_t
+#define HAL_TIMER_TYPE_MAX  UINT16_MAX
+
+extern uint32_t GetStepperTimerClkFreq();
+
+// Timer prescaler calculations
+#define STEPPER_TIMER_PRESCALE      (GetStepperTimerClkFreq() / STEPPER_TIMER_RATE)	// Prescaler = 30
+#define PULSE_TIMER_PRESCALE        STEPPER_TIMER_PRESCALE
+#define STEPPER_TIMER_TICKS_PER_US  ((STEPPER_TIMER_RATE) / 1000000)				        // Stepper timer ticks per µs
+#define PULSE_TIMER_RATE            STEPPER_TIMER_RATE
+#define PULSE_TIMER_TICKS_PER_US    STEPPER_TIMER_TICKS_PER_US
+
+// Timer interrupt priorities
+#define STEP_TIMER_IRQ_PRIORITY 2
+#define TEMP_TIMER_IRQ_PRIORITY 14
+
+#define ENABLE_STEPPER_DRIVER_INTERRUPT()   HAL_timer_enable_interrupt(MF_TIMER_STEP)
+#define DISABLE_STEPPER_DRIVER_INTERRUPT()  HAL_timer_disable_interrupt(MF_TIMER_STEP)
+#define STEPPER_ISR_ENABLED()               HAL_timer_interrupt_enabled(MF_TIMER_STEP)
+#define ENABLE_TEMPERATURE_INTERRUPT()		  HAL_timer_enable_interrupt(MF_TIMER_TEMP)
+#define DISABLE_TEMPERATURE_INTERRUPT()     HAL_timer_disable_interrupt(MF_TIMER_TEMP)
+
+extern void Step_Handler();
+extern void Temp_Handler();
+
+#ifndef HAL_STEP_TIMER_ISR
+  #define HAL_STEP_TIMER_ISR() void Step_Handler()
+#endif
+#ifndef HAL_TEMP_TIMER_ISR
+  #define HAL_TEMP_TIMER_ISR() void Temp_Handler()
+#endif
+
+extern GeneralTimer& Step_Timer;
+extern GeneralTimer& Temp_Timer;
+
+extern bool is_step_timer_initialized;
+extern bool is_temp_timer_initialized;
+
+// Build-time mapping between timer base and index. Used in timers.cpp and fast_pwm.cpp
+static inline constexpr struct {timer::TIMER_Base base; uint8_t timer_number;} base_to_index[] = {
+  { timer::TIMER_Base::TIMER0_BASE, 0 },
+  { timer::TIMER_Base::TIMER1_BASE, 1 },
+  { timer::TIMER_Base::TIMER2_BASE, 2 },
+  { timer::TIMER_Base::TIMER3_BASE, 3 },
+  { timer::TIMER_Base::TIMER4_BASE, 4 },
+  { timer::TIMER_Base::TIMER5_BASE, 5 },
+  { timer::TIMER_Base::TIMER6_BASE, 6 },
+  { timer::TIMER_Base::TIMER7_BASE, 7 }
+};
+
+// Converts a timer base to an integer timer index.
+constexpr int timer_base_to_index(timer::TIMER_Base base) {
+  for (const auto& timer : base_to_index) {
+    if (timer.base == base) {
+      return static_cast<int>(timer.timer_number);
+    }
+  }
+  return -1;
+}
+
+// ------------------------
+// Public functions
+// ------------------------
+
+void HAL_timer_start(const uint8_t timer, const uint32_t frequency);
+void HAL_timer_enable_interrupt(const uint8_t timer);
+void HAL_timer_disable_interrupt(const uint8_t timer);
+bool HAL_timer_interrupt_enabled(const uint8_t timer);
+
+// Configure timer priorities for peripherals such as Software Serial or Servos.
+// Exposed here to allow all timer priority information to reside in timers.cpp
+void SetTimerInterruptPriorities();
+
+// FORCE_INLINE because these are used in performance-critical situations
+FORCE_INLINE bool HAL_timer_initialized(const uint8_t timer_number) {
+  return (timer_number == MF_TIMER_STEP) ? is_step_timer_initialized :
+         (timer_number == MF_TIMER_TEMP) ? is_temp_timer_initialized :
+         false;
+}
+
+FORCE_INLINE static hal_timer_t HAL_timer_get_count(const uint8_t timer_number) {
+  if (!HAL_timer_initialized(timer_number)) return 0U;
+
+  GeneralTimer& timer = (timer_number == MF_TIMER_STEP) ? Step_Timer : Temp_Timer;
+
+  return (timer_number == MF_TIMER_STEP || timer_number == MF_TIMER_TEMP) 
+         ? timer.getCounter(TimerFormat::TICK) 
+         : 0U;
+}
+
+FORCE_INLINE static void HAL_timer_set_compare(const uint8_t timer_number, const hal_timer_t value) {
+  if (!HAL_timer_initialized(timer_number)) return;
+
+  const uint32_t new_value = static_cast<uint32_t>(value + 1U);
+  GeneralTimer& timer = (timer_number == MF_TIMER_STEP) ? Step_Timer : Temp_Timer;
+
+  if (timer_number == MF_TIMER_STEP || timer_number == MF_TIMER_TEMP) {
+    timer.setRolloverValue(new_value, TimerFormat::TICK);
+    if (value < static_cast<hal_timer_t>(timer.getCounter(TimerFormat::TICK)))
+      timer.refresh();
+  }
+}
+
+#define HAL_timer_isr_prologue(T) NOOP
+#define HAL_timer_isr_epilogue(T) NOOP

Marlin/src/HAL/GD32_MFL/u8g/LCD_defines.h

@@ -0,0 +1,26 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+// MFL LCD-specific defines
+uint8_t u8g_com_HAL_MFL_sw_spi_fn(u8g_t* u8g, uint8_t msg, uint8_t arg_val, void* arg_ptr); // u8g_com_mfl_swspi.cpp
+#define U8G_COM_HAL_SW_SPI_FN u8g_com_HAL_MFL_sw_spi_fn

Marlin/src/HAL/HC32/eeprom_wired.cpp

@@ -2,6 +2,9 @@
  * Marlin 3D Printer Firmware
  * Copyright (c) 2023 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or

Marlin/src/HAL/HC32/pinsDebug.h

@@ -2,6 +2,9 @@
  * Marlin 3D Printer Firmware
  * Copyright (c) 2023 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or

Marlin/src/HAL/HC32/spi_pins.h

@@ -2,6 +2,9 @@
  * Marlin 3D Printer Firmware
  * Copyright (c) 2023 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
  *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
  * This program is free software: you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation, either version 3 of the License, or

Marlin/src/HAL/platforms.h

@@ -37,6 +37,8 @@
   #define HAL_PATH(PATH, NAME) XSTR(PATH/HAL/LPC1768/NAME)
 #elif defined(ARDUINO_ARCH_HC32)
   #define HAL_PATH(PATH, NAME) XSTR(PATH/HAL/HC32/NAME)
+#elif defined(ARDUINO_ARCH_MFL)
+  #define HAL_PATH(PATH, NAME) XSTR(PATH/HAL/GD32_MFL/NAME)
 #elif defined(__STM32F1__) || defined(TARGET_STM32F1)
   #define HAL_PATH(PATH, NAME) XSTR(PATH/HAL/STM32F1/NAME)
 #elif defined(ARDUINO_ARCH_STM32)

Marlin/src/HAL/shared/servo.h

@@ -76,6 +76,8 @@
   #include "../LPC1768/Servo.h"
 #elif defined(ARDUINO_ARCH_HC32)
   #include "../HC32/Servo.h"
+#elif defined(ARDUINO_ARCH_MFL)
+  #include "../GD32_MFL/Servo.h"
 #elif defined(__STM32F1__) || defined(TARGET_STM32F1)
   #include "../STM32F1/Servo.h"
 #elif defined(ARDUINO_ARCH_STM32)

Marlin/src/core/boards.h

@@ -383,7 +383,7 @@
 #define BOARD_CHITU3D_V6              5036  // Chitu3D TronXY X5SA V6 Board (STM32F103ZE)
 #define BOARD_CHITU3D_V9              5037  // Chitu3D TronXY X5SA V9 Board (STM32F103ZE)
 #define BOARD_CREALITY_V4             5038  // Creality v4.x (STM32F103RC / STM32F103RE)
-#define BOARD_CREALITY_V422           5039  // Creality v4.2.2 (STM32F103RC / STM32F103RE)
+#define BOARD_CREALITY_V422           5039  // Creality v4.2.2 (STM32F103RC / STM32F103RE) ... GD32 Variant Below!
 #define BOARD_CREALITY_V423           5040  // Creality v4.2.3 (STM32F103RC / STM32F103RE)
 #define BOARD_CREALITY_V425           5041  // Creality v4.2.5 (STM32F103RC / STM32F103RE)
 #define BOARD_CREALITY_V427           5042  // Creality v4.2.7 (STM32F103RC / STM32F103RE)
@@ -552,6 +552,12 @@
 #define BOARD_AQUILA_V101             7200  // Voxelab Aquila V1.0.0/V1.0.1/V1.0.2/V1.0.3 as found in the Voxelab Aquila X2 and C2
 #define BOARD_CREALITY_ENDER2P_V24S4  7201  // Creality Ender 2 Pro v2.4.S4_170 (HC32f460kcta)
 
+//
+// GD32 ARM Cortex-M4
+//
+
+#define BOARD_CREALITY_V422_GD32_MFL  7300  // Creality V4.2.2 MFL (GD32F303RE) ... STM32 Variant Above!
+
 //
 // Raspberry Pi
 //

Marlin/src/inc/SanityCheck.h

@@ -241,10 +241,10 @@ static_assert(COUNT(arm) == LOGICAL_AXES, "AXIS_RELATIVE_MODES must contain " _L
   #error "SERIAL_XON_XOFF and SERIAL_STATS_* features not supported on USB-native AVR devices."
 #endif
 
-// Serial DMA is only available for some STM32 MCUs and HC32
+// Serial DMA is only available for some STM32 MCUs, HC32 and GD32
 #if ENABLED(SERIAL_DMA)
-  #ifdef ARDUINO_ARCH_HC32
-    // checks for HC32 are located in HAL/HC32/inc/SanityCheck.h
+  #if ANY(ARDUINO_ARCH_HC32, ARDUINO_ARCH_MFL)
+    // See HAL/.../inc/SanityCheck.h
   #elif DISABLED(HAL_STM32) || NONE(STM32F0xx, STM32F1xx, STM32F2xx, STM32F4xx, STM32F7xx, STM32H7xx)
     #error "SERIAL_DMA is only available for some STM32 MCUs and requires HAL/STM32."
   #elif !defined(HAL_UART_MODULE_ENABLED) || defined(HAL_UART_MODULE_ONLY)

Marlin/src/inc/Warnings.cpp

@@ -696,9 +696,16 @@
   #warning "Don't forget to update your TFT settings in Configuration.h."
 #endif
 
-#if ENABLED(EMIT_CREALITY_422_WARNING) && DISABLED(NO_CREALITY_422_DRIVER_WARNING)
+#if ENABLED(EMIT_CREALITY_422_WARNING)
+  #if DISABLED(NO_CREALITY_422_MCU_WARNING)
+    #warning "Double-check your 4.2.2 board for STM32 / GD32. Use BOARD_CREALITY_V422 or BOARD_CREALITY_V422_GD32_MFL as appropriate for your MCU."
+    #warning "GD32 Serial Ports are numbered starting from 0. STM32 Serial Ports are numbered starting from 1."
+    #warning "(Define NO_CREALITY_422_MCU_WARNING to suppress these warnings.)"
+  #endif
+  #if DISABLED(NO_CREALITY_422_DRIVER_WARNING)
     // Driver labels: A=TMC2208, B=TMC2209, C=HR4988, E=A4988, H=TMC2225, H8=HR4988
     #warning "Creality 4.2.2 boards come with a variety of stepper drivers. Check the board label (typically on SD Card module) and set the correct *_DRIVER_TYPE! (A/H: TMC2208_STANDALONE  B: TMC2209_STANDALONE  C/E/H8: A4988). (Define NO_CREALITY_422_DRIVER_WARNING to suppress this warning.)"
+  #endif
 #endif
 
 #if ENABLED(PRINTCOUNTER_SYNC)

Marlin/src/lcd/dogm/u8g/u8g_dev_st7920_128x64_HAL.cpp

@@ -199,7 +199,7 @@ u8g_dev_t u8g_dev_st7920_128x64_HAL_4x_sw_spi = { u8g_dev_st7920_128x64_HAL_4x_f
 U8G_PB_DEV(u8g_dev_st7920_128x64_HAL_hw_spi, LCD_PIXEL_WIDTH, LCD_PIXEL_HEIGHT, PAGE_HEIGHT, u8g_dev_st7920_128x64_HAL_fn, U8G_COM_ST7920_HAL_HW_SPI);
 u8g_dev_t u8g_dev_st7920_128x64_HAL_4x_hw_spi = { u8g_dev_st7920_128x64_HAL_4x_fn, &u8g_dev_st7920_128x64_HAL_4x_pb, U8G_COM_ST7920_HAL_HW_SPI };
 
-#if NONE(__AVR__, ARDUINO_ARCH_STM32, ARDUINO_ARCH_ESP32) || defined(U8G_HAL_LINKS)
+#if NONE(__AVR__, ARDUINO_ARCH_STM32, ARDUINO_ARCH_ESP32, ARDUINO_ARCH_MFL) || defined(U8G_HAL_LINKS)
   // Also use this device for HAL version of RRD class. This results in the same device being used
   // for the ST7920 for HAL systems no matter what is selected in marlinui_DOGM.h.
   u8g_dev_t u8g_dev_st7920_128x64_rrd_sw_spi = { u8g_dev_st7920_128x64_HAL_4x_fn, &u8g_dev_st7920_128x64_HAL_4x_pb, U8G_COM_ST7920_HAL_SW_SPI };

Marlin/src/lcd/dogm/u8g/ultralcd_st7920_u8glib_rrd_AVR.cpp

@@ -25,7 +25,7 @@
 
 #include "../../../inc/MarlinConfigPre.h"
 
-#if ANY(__AVR__, ARDUINO_ARCH_STM32, ARDUINO_ARCH_ESP32)
+#if ANY(__AVR__, ARDUINO_ARCH_STM32, ARDUINO_ARCH_ESP32, ARDUINO_ARCH_MFL)
 
 #include "../../../inc/MarlinConfig.h"
 
@@ -193,4 +193,4 @@ u8g_dev_t u8g_dev_st7920_128x64_rrd_sw_spi = { u8g_dev_rrd_st7920_128x64_fn, &u8
 #endif
 
 #endif // IS_U8GLIB_ST7920
-#endif // __AVR__ || ARDUINO_ARCH_STM32 || ARDUINO_ARCH_ESP32
+#endif // __AVR__ || ARDUINO_ARCH_STM32 || ARDUINO_ARCH_ESP32 || ARDUINO_ARCH_MFL

Marlin/src/libs/BL24CXX.cpp

@@ -48,7 +48,7 @@
 #ifdef __STM32F1__
   #define SDA_IN()  do{ PIN_MAP[IIC_EEPROM_SDA].gpio_device->regs->CRH &= 0XFFFF0FFF; PIN_MAP[IIC_EEPROM_SDA].gpio_device->regs->CRH |= 8 << 12; }while(0)
   #define SDA_OUT() do{ PIN_MAP[IIC_EEPROM_SDA].gpio_device->regs->CRH &= 0XFFFF0FFF; PIN_MAP[IIC_EEPROM_SDA].gpio_device->regs->CRH |= 3 << 12; }while(0)
-#elif defined(STM32F1) || defined(STM32F4) || defined(ARDUINO_ARCH_HC32)
+#elif ANY(STM32F1, STM32F4, ARDUINO_ARCH_HC32, ARDUINO_ARCH_MFL)
   #define SDA_IN()  SET_INPUT(IIC_EEPROM_SDA)
   #define SDA_OUT() SET_OUTPUT(IIC_EEPROM_SDA)
 #endif

Marlin/src/pins/gd32f3/pins_CREALITY_V422_GD32_MFL.h

@@ -0,0 +1,37 @@
+/**
+ * Marlin 3D Printer Firmware
+ * Copyright (c) 2025 MarlinFirmware [https://github.com/MarlinFirmware/Marlin]
+ *
+ * Based on Sprinter and grbl.
+ * Copyright (c) 2011 Camiel Gubbels / Erik van der Zalm
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ *
+ */
+#pragma once
+
+/**
+ * Creality MFL GD32 V4.2.2 (GD32F303RE) board pin assignments
+ */
+
+#define ALLOW_GD32F3
+
+#ifndef BOARD_INFO_NAME
+  #define BOARD_INFO_NAME      "Creality V4.2.2 MFL"
+#endif
+#ifndef DEFAULT_MACHINE_NAME
+  #define DEFAULT_MACHINE_NAME "Ender-3 MFL"
+#endif
+
+#include "../stm32f1/pins_CREALITY_V4.h"

Marlin/src/pins/pins.h

@@ -964,6 +964,13 @@
 #elif MB(CREALITY_ENDER2P_V24S4)
   #include "hc32f4/pins_CREALITY_ENDER2P_V24S4.h"   // HC32F460                             env:HC32F460C_e2p24s4
 
+//
+// GD32 ARM Cortex-M4
+//
+
+#elif MB(CREALITY_V422_GD32_MFL)
+  #include "gd32f3/pins_CREALITY_V422_GD32_MFL.h"   // GD32F303RE                           env:GD32F303RE_creality_mfl
+
 //
 // Raspberry Pi RP2040
 //

Marlin/src/pins/pinsDebug_list.h

@@ -27,6 +27,8 @@
 
 #if TARGET_LPC1768
   #define ANALOG_OK(PN) (WITHIN(PN, P0_02, P0_03) || WITHIN(PN, P0_23, P0_26) || WITHIN(PN, P1_30, P1_31))
+#elif ARDUINO_ARCH_MFL
+  #define ANALOG_OK(PN) (WITHIN(PN, 0, 7) || WITHIN(PN, 16, 17) || WITHIN(PN, 32, 37))
 #else
   #define ANALOG_OK(PN) WITHIN(PN, 0, NUM_ANALOG_INPUTS - 1)
 #endif

Marlin/src/pins/stm32f1/env_validate.h

@@ -23,13 +23,16 @@
 #define ENV_VALIDATE_H
 
 #if NOT_TARGET(__STM32F1__, STM32F1)
-  #if DISABLED(ALLOW_STM32F4)
+  #if NONE(ALLOW_STM32F4, ALLOW_GD32F3)
     #error "Oops! Select an STM32F1 board in 'Tools > Board.'"
-  #elif NOT_TARGET(STM32F4)
+  #elif ENABLED(ALLOW_STM32F4) && NOT_TARGET(STM32F4)
     #error "Oops! Select an STM32F4 board in 'Tools > Board.'"
+  #elif ENABLED(ALLOW_GD32F3) && NOT_TARGET(ARDUINO_ARCH_MFL)
+    #error "Oops! Make sure you have a GD32F3 MFL environment selected."
   #endif
 #endif
 
 #undef ALLOW_STM32F4
+#undef ALLOW_GD32F3
 
 #endif

README.md

@@ -58,12 +58,13 @@ Every new HAL opens up a world of hardware. At this time we need HALs for RP2040
   [Teensy++ 2.0](//www.microchip.com/en-us/product/AT90USB1286)|AT90USB1286|Printrboard
   [Arduino Due](//www.arduino.cc/en/Guide/ArduinoDue)|SAM3X8E|RAMPS-FD, RADDS, RAMPS4DUE
   [ESP32](//github.com/espressif/arduino-esp32)|ESP32|FYSETC E4, E4d@BOX, MRR
+  [GD32](//www.gigadevice.com/)|GD32 ARM Cortex-M4|Creality MFL GD32 V4.2.2
   [HC32](//www.huazhoucn.com/)|HC32|Ender-2 Pro, Voxelab Aquila
   [LPC1768](//www.nxp.com/products/processors-and-microcontrollers/arm-microcontrollers/general-purpose-mcus/lpc1700-cortex-m3/512-kb-flash-64-kb-sram-ethernet-usb-lqfp100-package:LPC1768FBD100)|ARM® Cortex-M3|MKS SBASE, Re-ARM, Selena Compact
   [LPC1769](//www.nxp.com/products/processors-and-microcontrollers/arm-microcontrollers/general-purpose-mcus/lpc1700-cortex-m3/512-kb-flash-64-kb-sram-ethernet-usb-lqfp100-package:LPC1769FBD100)|ARM® Cortex-M3|Smoothieboard, Azteeg X5 mini, TH3D EZBoard
+  [Pico RP2040](//www.raspberrypi.com/documentation/microcontrollers/pico-series.html)|Dual Cortex M0+|BigTreeTech SKR Pico
   [STM32F103](//www.st.com/en/microcontrollers-microprocessors/stm32f103.html)|ARM® Cortex-M3|Malyan M200, GTM32 Pro, MKS Robin, BTT SKR Mini
   [STM32F401](//www.st.com/en/microcontrollers-microprocessors/stm32f401.html)|ARM® Cortex-M4|ARMED, Rumba32, SKR Pro, Lerdge, FYSETC S6, Artillery Ruby
-  [Pico RP2040](//www.raspberrypi.com/documentation/microcontrollers/pico-series.html)|Dual Cortex M0+|BigTreeTech SKR Pico
   [STM32F7x6](//www.st.com/en/microcontrollers-microprocessors/stm32f7x6.html)|ARM® Cortex-M7|The Borg, RemRam V1
   [STM32G0B1RET6](//www.st.com/en/microcontrollers-microprocessors/stm32g0x1.html)|ARM® Cortex-M0+|BigTreeTech SKR mini E3 V3.0
   [STM32H743xIT6](//www.st.com/en/microcontrollers-microprocessors/stm32h743-753.html)|ARM® Cortex-M7|BigTreeTech SKR V3.0, SKR EZ V3.0, SKR SE BX V2.0/V3.0

buildroot/tests/GD32F303RE_creality_mfl

@@ -0,0 +1,17 @@
+#!/usr/bin/env bash
+#
+# Build tests for GD32F303RE_creality_mfl
+#
+
+# exit on first failure
+set -e
+
+restore_configs
+opt_set MOTHERBOARD BOARD_CREALITY_V422_GD32_MFL SERIAL_PORT 0
+opt_enable EEPROM_SETTINGS SDSUPPORT EMERGENCY_PARSER FAN_SOFT_PWM PINS_DEBUGGING
+opt_add NO_CREALITY_422_DRIVER_WARNING
+opt_add NO_AUTO_ASSIGN_WARNING
+exec_test $1 $2 "Creality V4.2.2 MFL GD32 Default Configuration" "$3"
+
+# cleanup
+restore_configs

ini/gd32.ini

@@ -0,0 +1,47 @@
+#
+# Marlin Firmware
+# PlatformIO Configuration File
+#
+
+####################################
+#
+# HAL/MFL GD32 Environments
+#
+####################################
+
+[gd32_base]
+platform            = https://github.com/bmourit/platform-mfl/archive/refs/tags/V1.0.2.zip
+board_build.core    = gd32
+build_src_filter    = ${common.default_src_filter} +<src/HAL/GD32_MFL> +<src/HAL/shared/backtrace>
+build_unflags       = -std=gnu++11 -std=gnu++14 -std=gnu++17
+build_flags         = -std=gnu++23
+                      -DARDUINO_ARCH_MFL
+                      -DPLATFORM_M997_SUPPORT
+                      -DTIMER_IRQ_PRIORITY=12
+                      -DADC_RESOLUTION=12
+                      -DCORE_DEBUG
+                      -Wno-deprecated-declarations
+                      -Wno-volatile
+extra_scripts       = ${common.extra_scripts}
+
+#
+# Creality (GD32F303RE)
+#
+[env:GD32F303RE_creality_mfl]
+extends                     = gd32_base
+board                       = mfl_creality_422
+board_build.offset          = 0x7000
+board_build.rename          = firmware-{time}.bin
+board_upload.offset_address = 0x08007000
+build_flags                 = ${gd32_base.build_flags}
+                              -DMCU_GD32F303RE
+                              -DGD32F303RE
+                              -DTIMER_TONE=2
+                              -DSS_TIMER=3
+                              -DTIMER_SERVO=4
+                              -DTRANSFER_CLOCK_DIV=8
+                              -fsingle-precision-constant
+extra_scripts = ${gd32_base.extra_scripts}
+                buildroot/share/PlatformIO/scripts/offset_and_rename.py
+
+monitor_speed               = 115200

platformio.ini

@@ -22,6 +22,7 @@ extra_configs =
     ini/esp32.ini
     ini/features.ini
     ini/hc32.ini
+    ini/gd32.ini
     ini/lpc176x.ini
     ini/native.ini
     ini/samd21.ini