Marlin_Firmware/Marlin/src/HAL/HAL_DUE/MarlinSerial_Due.cpp

/**
 * Marlin 3D Printer Firmware
 * Copyright (C) 2016 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 <http://www.gnu.org/licenses/>.
 *
 */

/**
 * MarlinSerial_Due.cpp - Hardware serial library for Arduino DUE
 * Copyright (c) 2017 Eduardo José Tagle. All right reserved
 * Based on MarlinSerial for AVR, copyright (c) 2006 Nicholas Zambetti.  All right reserved.
 */
#ifdef ARDUINO_ARCH_SAM

#include "../../inc/MarlinConfig.h"

#include "MarlinSerial_Due.h"
#include "InterruptVectors_Due.h"
#include "../../Marlin.h"

// Based on selected port, use the proper configuration
#if SERIAL_PORT == -1
  #define HWUART UART
  #define HWUART_IRQ UART_IRQn
  #define HWUART_IRQ_ID ID_UART
#elif SERIAL_PORT == 0
  #define HWUART USART0
  #define HWUART_IRQ USART0_IRQn
  #define HWUART_IRQ_ID ID_USART0
#elif SERIAL_PORT == 1
  #define HWUART USART1
  #define HWUART_IRQ USART1_IRQn
  #define HWUART_IRQ_ID ID_USART1
#elif SERIAL_PORT == 2
  #define HWUART USART2
  #define HWUART_IRQ USART2_IRQn
  #define HWUART_IRQ_ID ID_USART2
#elif SERIAL_PORT == 3
  #define HWUART USART3
  #define HWUART_IRQ USART3_IRQn
  #define HWUART_IRQ_ID ID_USART3
#endif

struct ring_buffer_r {
  unsigned char buffer[RX_BUFFER_SIZE];
  volatile ring_buffer_pos_t head, tail;
};

#if TX_BUFFER_SIZE > 0
  struct ring_buffer_t {
    unsigned char buffer[TX_BUFFER_SIZE];
    volatile uint8_t head, tail;
  };
#endif

ring_buffer_r rx_buffer = { { 0 }, 0, 0 };
#if TX_BUFFER_SIZE > 0
  ring_buffer_t tx_buffer = { { 0 }, 0, 0 };
  static bool _written;
#endif

#if ENABLED(SERIAL_XON_XOFF)
  constexpr uint8_t XON_XOFF_CHAR_SENT = 0x80;  // XON / XOFF Character was sent
  constexpr uint8_t XON_XOFF_CHAR_MASK = 0x1F;  // XON / XOFF character to send
  // XON / XOFF character definitions
  constexpr uint8_t XON_CHAR  = 17;
  constexpr uint8_t XOFF_CHAR = 19;
  uint8_t xon_xoff_state = XON_XOFF_CHAR_SENT | XON_CHAR;

  // Validate that RX buffer size is at least 4096 bytes- According to several experiments, on
  // the original Arduino Due that uses a ATmega16U2 as USB to serial bridge, due to the introduced
  // latencies, at least 2959 bytes of RX buffering (when transmitting at 250kbits/s) are required
  // to avoid overflows.

  #if RX_BUFFER_SIZE < 4096
    #error Arduino DUE requires at least 4096 bytes of RX buffer to avoid buffer overflows when using XON/XOFF handshake
  #endif
#endif

#if ENABLED(SERIAL_STATS_DROPPED_RX)
  uint8_t rx_dropped_bytes = 0;
#endif

#if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
  ring_buffer_pos_t rx_max_enqueued = 0;
#endif

// A SW memory barrier, to ensure GCC does not overoptimize loops
#define sw_barrier() asm volatile("": : :"memory");

#if ENABLED(EMERGENCY_PARSER)

  // Currently looking for: M108, M112, M410
  // If you alter the parser please don't forget to update the capabilities in Conditionals_post.h

  FORCE_INLINE void emergency_parser(const uint8_t c) {

    static e_parser_state state = state_RESET;

    switch (state) {
      case state_RESET:
        switch (c) {
          case ' ': break;
          case 'N': state = state_N;      break;
          case 'M': state = state_M;      break;
          default: state = state_IGNORE;
        }
        break;

      case state_N:
        switch (c) {
          case '0': case '1': case '2':
          case '3': case '4': case '5':
          case '6': case '7': case '8':
          case '9': case '-': case ' ':   break;
          case 'M': state = state_M;      break;
          default:  state = state_IGNORE;
        }
        break;

      case state_M:
        switch (c) {
          case ' ': break;
          case '1': state = state_M1;     break;
          case '4': state = state_M4;     break;
          default: state = state_IGNORE;
        }
        break;

      case state_M1:
        switch (c) {
          case '0': state = state_M10;    break;
          case '1': state = state_M11;    break;
          default: state = state_IGNORE;
        }
        break;

      case state_M10:
        state = (c == '8') ? state_M108 : state_IGNORE;
        break;

      case state_M11:
        state = (c == '2') ? state_M112 : state_IGNORE;
        break;

      case state_M4:
        state = (c == '1') ? state_M41 : state_IGNORE;
        break;

      case state_M41:
        state = (c == '0') ? state_M410 : state_IGNORE;
        break;

      case state_IGNORE:
        if (c == '\n') state = state_RESET;
        break;

      default:
        if (c == '\n') {
          switch (state) {
            case state_M108:
              wait_for_user = wait_for_heatup = false;
              break;
            case state_M112:
              kill(PSTR(MSG_KILLED));
              break;
            case state_M410:
              quickstop_stepper();
              break;
            default:
              break;
          }
          state = state_RESET;
        }
    }
  }

#endif // EMERGENCY_PARSER

FORCE_INLINE void store_rxd_char() {

  const ring_buffer_pos_t h = rx_buffer.head,
                          i = (ring_buffer_pos_t)(h + 1) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);

    // Read the character
  const uint8_t c = HWUART->UART_RHR;

  // If the character is to be stored at the index just before the tail
  // (such that the head would advance to the current tail), the buffer is
  // critical, so don't write the character or advance the head.
  if (i != rx_buffer.tail) {
    rx_buffer.buffer[h] = c;
    rx_buffer.head = i;
  }
  #if ENABLED(SERIAL_STATS_DROPPED_RX)
    else if (!++rx_dropped_bytes) ++rx_dropped_bytes;
  #endif

  #if ENABLED(SERIAL_STATS_MAX_RX_QUEUED)
    // calculate count of bytes stored into the RX buffer
    ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(rx_buffer.head - rx_buffer.tail) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
    // Keep track of the maximum count of enqueued bytes
    NOLESS(rx_max_enqueued, rx_count);
  #endif

  #if ENABLED(SERIAL_XON_XOFF)

    // for high speed transfers, we can use XON/XOFF protocol to do
    // software handshake and avoid overruns.
    if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XON_CHAR) {

      // calculate count of bytes stored into the RX buffer
      ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(rx_buffer.head - rx_buffer.tail) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);

      // if we are above 12.5% of RX buffer capacity, send XOFF before
      // we run out of RX buffer space .. We need 325 bytes @ 250kbits/s to
      // let the host react and stop sending bytes. This translates to 13mS
      // propagation time.
      if (rx_count >= (RX_BUFFER_SIZE) / 8) {
        // If TX interrupts are disabled and data register is empty,
        // just write the byte to the data register and be done. This
        // shortcut helps significantly improve the effective datarate
        // at high (>500kbit/s) bitrates, where interrupt overhead
        // becomes a slowdown.
        if (!(HWUART->UART_IMR & UART_IMR_TXRDY) && (HWUART->UART_SR & UART_SR_TXRDY)) {
          // Send an XOFF character
          HWUART->UART_THR = XOFF_CHAR;

          // And remember it was sent
          xon_xoff_state = XOFF_CHAR | XON_XOFF_CHAR_SENT;
        }
        else {
          // TX interrupts disabled, but buffer still not empty ... or
          // TX interrupts enabled. Reenable TX ints and schedule XOFF
          // character to be sent
          #if TX_BUFFER_SIZE > 0
            HWUART->UART_IER = UART_IER_TXRDY;
            xon_xoff_state = XOFF_CHAR;
          #else
            // We are not using TX interrupts, we will have to send this manually
            while (!(HWUART->UART_SR & UART_SR_TXRDY)) { sw_barrier(); };
            HWUART->UART_THR = XOFF_CHAR;
            // And remember we already sent it
            xon_xoff_state = XOFF_CHAR | XON_XOFF_CHAR_SENT;
          #endif
        }
      }
    }
  #endif // SERIAL_XON_XOFF

  #if ENABLED(EMERGENCY_PARSER)
    emergency_parser(c);
  #endif
}

#if TX_BUFFER_SIZE > 0

  FORCE_INLINE void _tx_thr_empty_irq(void) {
    // If interrupts are enabled, there must be more data in the output
    // buffer.

    #if ENABLED(SERIAL_XON_XOFF)
      // Do a priority insertion of an XON/XOFF char, if needed.
      const uint8_t state = xon_xoff_state;
      if (!(state & XON_XOFF_CHAR_SENT)) {
        HWUART->UART_THR = state & XON_XOFF_CHAR_MASK;
        xon_xoff_state = state | XON_XOFF_CHAR_SENT;
      }
      else
    #endif
      { // Send the next byte
        const uint8_t t = tx_buffer.tail, c = tx_buffer.buffer[t];
        tx_buffer.tail = (t + 1) & (TX_BUFFER_SIZE - 1);
        HWUART->UART_THR = c;
      }

    // Disable interrupts if the buffer is empty
    if (tx_buffer.head == tx_buffer.tail)
      HWUART->UART_IDR = UART_IDR_TXRDY;
  }

#endif // TX_BUFFER_SIZE > 0

static void UART_ISR(void) {
  uint32_t status = HWUART->UART_SR;

  // Did we receive data?
  if (status & UART_SR_RXRDY)
    store_rxd_char();

  #if TX_BUFFER_SIZE > 0
    // Do we have something to send, and TX interrupts are enabled (meaning something to send) ?
    if ((status & UART_SR_TXRDY) && (HWUART->UART_IMR & UART_IMR_TXRDY))
      _tx_thr_empty_irq();
  #endif

  // Acknowledge errors
  if ((status & UART_SR_OVRE) || (status & UART_SR_FRAME)) {
    // TODO: error reporting outside ISR
    HWUART->UART_CR = UART_CR_RSTSTA;
  }
}

// Public Methods

void MarlinSerial::begin(const long baud_setting) {

  // Disable UART interrupt in NVIC
  NVIC_DisableIRQ( HWUART_IRQ );

  // Disable clock
  pmc_disable_periph_clk( HWUART_IRQ_ID );

  // Configure PMC
  pmc_enable_periph_clk( HWUART_IRQ_ID );

  // Disable PDC channel
  HWUART->UART_PTCR = UART_PTCR_RXTDIS | UART_PTCR_TXTDIS;

  // Reset and disable receiver and transmitter
  HWUART->UART_CR = UART_CR_RSTRX | UART_CR_RSTTX | UART_CR_RXDIS | UART_CR_TXDIS;

  // Configure mode: 8bit, No parity, 1 bit stop
  HWUART->UART_MR = UART_MR_CHMODE_NORMAL | US_MR_CHRL_8_BIT | US_MR_NBSTOP_1_BIT | UART_MR_PAR_NO;

  // Configure baudrate (asynchronous, no oversampling)
  HWUART->UART_BRGR = (SystemCoreClock / (baud_setting << 4));

  // Configure interrupts
  HWUART->UART_IDR = 0xFFFFFFFF;
  HWUART->UART_IER = UART_IER_RXRDY | UART_IER_OVRE | UART_IER_FRAME;

  // Install interrupt handler
  install_isr(HWUART_IRQ, UART_ISR);

  // Enable UART interrupt in NVIC
  NVIC_EnableIRQ(HWUART_IRQ);

  // Enable receiver and transmitter
  HWUART->UART_CR = UART_CR_RXEN | UART_CR_TXEN;

  #if TX_BUFFER_SIZE > 0
    _written = false;
  #endif
}

void MarlinSerial::end() {
  // Disable UART interrupt in NVIC
  NVIC_DisableIRQ( HWUART_IRQ );

  pmc_disable_periph_clk( HWUART_IRQ_ID );
}

void MarlinSerial::checkRx(void) {
  if (HWUART->UART_SR & UART_SR_RXRDY) {
    CRITICAL_SECTION_START;
    store_rxd_char();
    CRITICAL_SECTION_END;
  }
}

int MarlinSerial::peek(void) {
  CRITICAL_SECTION_START;
  const int v = rx_buffer.head == rx_buffer.tail ? -1 : rx_buffer.buffer[rx_buffer.tail];
  CRITICAL_SECTION_END;
  return v;
}

int MarlinSerial::read(void) {
  int v;
  CRITICAL_SECTION_START;
  const ring_buffer_pos_t t = rx_buffer.tail;
  if (rx_buffer.head == t)
    v = -1;
  else {
    v = rx_buffer.buffer[t];
    rx_buffer.tail = (ring_buffer_pos_t)(t + 1) & (RX_BUFFER_SIZE - 1);

    #if ENABLED(SERIAL_XON_XOFF)
      if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XOFF_CHAR) {
        // Get count of bytes in the RX buffer
        ring_buffer_pos_t rx_count = (ring_buffer_pos_t)(rx_buffer.head - rx_buffer.tail) & (ring_buffer_pos_t)(RX_BUFFER_SIZE - 1);
        // When below 10% of RX buffer capacity, send XON before
        // running out of RX buffer bytes
        if (rx_count < (RX_BUFFER_SIZE) / 10) {
          xon_xoff_state = XON_CHAR | XON_XOFF_CHAR_SENT;
          CRITICAL_SECTION_END;       // End critical section before returning!
          writeNoHandshake(XON_CHAR);
          return v;
        }
      }
    #endif
  }
  CRITICAL_SECTION_END;
  return v;
}

ring_buffer_pos_t MarlinSerial::available(void) {
  CRITICAL_SECTION_START;
  const ring_buffer_pos_t h = rx_buffer.head, t = rx_buffer.tail;
  CRITICAL_SECTION_END;
  return (ring_buffer_pos_t)(RX_BUFFER_SIZE + h - t) & (RX_BUFFER_SIZE - 1);
}

void MarlinSerial::flush(void) {
  // Don't change this order of operations. If the RX interrupt occurs between
  // reading rx_buffer_head and updating rx_buffer_tail, the previous rx_buffer_head
  // may be written to rx_buffer_tail, making the buffer appear full rather than empty.
  CRITICAL_SECTION_START;
  rx_buffer.head = rx_buffer.tail;
  CRITICAL_SECTION_END;

  #if ENABLED(SERIAL_XON_XOFF)
    if ((xon_xoff_state & XON_XOFF_CHAR_MASK) == XOFF_CHAR) {
      xon_xoff_state = XON_CHAR | XON_XOFF_CHAR_SENT;
      writeNoHandshake(XON_CHAR);
    }
  #endif
}

#if TX_BUFFER_SIZE > 0

  uint8_t MarlinSerial::availableForWrite(void) {
    CRITICAL_SECTION_START;
    const uint8_t h = tx_buffer.head, t = tx_buffer.tail;
    CRITICAL_SECTION_END;
    return (uint8_t)(TX_BUFFER_SIZE + h - t) & (TX_BUFFER_SIZE - 1);
  }

  void MarlinSerial::write(const uint8_t c) {
    #if ENABLED(SERIAL_XON_XOFF)
      const uint8_t state = xon_xoff_state;
      if (!(state & XON_XOFF_CHAR_SENT)) {
        // Send 2 chars: XON/XOFF, then a user-specified char
        writeNoHandshake(state & XON_XOFF_CHAR_MASK);
        xon_xoff_state = state | XON_XOFF_CHAR_SENT;
      }
    #endif
    writeNoHandshake(c);
  }

  void MarlinSerial::writeNoHandshake(const uint8_t c) {
    _written = true;
    CRITICAL_SECTION_START;
    bool emty = (tx_buffer.head == tx_buffer.tail);
    CRITICAL_SECTION_END;
    // If the buffer and the data register is empty, just write the byte
    // to the data register and be done. This shortcut helps
    // significantly improve the effective datarate at high (>
    // 500kbit/s) bitrates, where interrupt overhead becomes a slowdown.
    if (emty && (HWUART->UART_SR & UART_SR_TXRDY)) {
      CRITICAL_SECTION_START;
        HWUART->UART_THR = c;
        HWUART->UART_IER = UART_IER_TXRDY;
      CRITICAL_SECTION_END;
      return;
    }
    const uint8_t i = (tx_buffer.head + 1) & (TX_BUFFER_SIZE - 1);

    // If the output buffer is full, there's nothing for it other than to
    // wait for the interrupt handler to empty it a bit
    while (i == tx_buffer.tail) {
      if (__get_PRIMASK()) {
        // Interrupts are disabled, so we'll have to poll the data
        // register empty flag ourselves. If it is set, pretend an
        // interrupt has happened and call the handler to free up
        // space for us.
        if (HWUART->UART_SR & UART_SR_TXRDY)
          _tx_thr_empty_irq();
      }
      else {
        // nop, the interrupt handler will free up space for us
      }
      sw_barrier();
    }

    tx_buffer.buffer[tx_buffer.head] = c;
    { CRITICAL_SECTION_START;
        tx_buffer.head = i;
        HWUART->UART_IER = UART_IER_TXRDY;
      CRITICAL_SECTION_END;
    }
    return;
  }

  void MarlinSerial::flushTX(void) {
    // TX
    // If we have never written a byte, no need to flush.
    if (!_written)
      return;

    while ((HWUART->UART_IMR & UART_IMR_TXRDY) || !(HWUART->UART_SR & UART_SR_TXEMPTY)) {
      if (__get_PRIMASK())
        if ((HWUART->UART_SR & UART_SR_TXRDY))
          _tx_thr_empty_irq();
      sw_barrier();
    }
    // If we get here, nothing is queued anymore (TX interrupts are disabled) and
    // the hardware finished tranmission (TXEMPTY is set).
  }

#else // TX_BUFFER_SIZE == 0

  void MarlinSerial::write(const uint8_t c) {
    #if ENABLED(SERIAL_XON_XOFF)
      // Do a priority insertion of an XON/XOFF char, if needed.
      const uint8_t state = xon_xoff_state;
      if (!(state & XON_XOFF_CHAR_SENT)) {
        writeNoHandshake(state & XON_XOFF_CHAR_MASK);
        xon_xoff_state = state | XON_XOFF_CHAR_SENT;
      }
    #endif
    writeNoHandshake(c);
  }

  void MarlinSerial::writeNoHandshake(const uint8_t c) {
    while (!(HWUART->UART_SR & UART_SR_TXRDY)) { sw_barrier(); };
    HWUART->UART_THR = c;
  }

#endif // TX_BUFFER_SIZE == 0

/**
* Imports from print.h
*/

void MarlinSerial::print(char c, int base) {
  print((long)c, base);
}

void MarlinSerial::print(unsigned char b, int base) {
  print((unsigned long)b, base);
}

void MarlinSerial::print(int n, int base) {
  print((long)n, base);
}

void MarlinSerial::print(unsigned int n, int base) {
  print((unsigned long)n, base);
}

void MarlinSerial::print(long n, int base) {
  if (base == 0)
    write(n);
  else if (base == 10) {
    if (n < 0) {
      print('-');
      n = -n;
    }
    printNumber(n, 10);
  }
  else
    printNumber(n, base);
}

void MarlinSerial::print(unsigned long n, int base) {
  if (base == 0) write(n);
  else printNumber(n, base);
}

void MarlinSerial::print(double n, int digits) {
  printFloat(n, digits);
}

void MarlinSerial::println(void) {
  print('\r');
  print('\n');
}

void MarlinSerial::println(const String& s) {
  print(s);
  println();
}

void MarlinSerial::println(const char c[]) {
  print(c);
  println();
}

void MarlinSerial::println(char c, int base) {
  print(c, base);
  println();
}

void MarlinSerial::println(unsigned char b, int base) {
  print(b, base);
  println();
}

void MarlinSerial::println(int n, int base) {
  print(n, base);
  println();
}

void MarlinSerial::println(unsigned int n, int base) {
  print(n, base);
  println();
}

void MarlinSerial::println(long n, int base) {
  print(n, base);
  println();
}

void MarlinSerial::println(unsigned long n, int base) {
  print(n, base);
  println();
}

void MarlinSerial::println(double n, int digits) {
  print(n, digits);
  println();
}

// Private Methods

void MarlinSerial::printNumber(unsigned long n, uint8_t base) {
  if (n) {
    unsigned char buf[8 * sizeof(long)]; // Enough space for base 2
    int8_t i = 0;
    while (n) {
      buf[i++] = n % base;
      n /= base;
    }
    while (i--)
      print((char)(buf[i] + (buf[i] < 10 ? '0' : 'A' - 10)));
  }
  else
    print('0');
}

void MarlinSerial::printFloat(double number, uint8_t digits) {
  // Handle negative numbers
  if (number < 0.0) {
    print('-');
    number = -number;
  }

  // Round correctly so that print(1.999, 2) prints as "2.00"
  double rounding = 0.5;
  for (uint8_t i = 0; i < digits; ++i)
    rounding *= 0.1;

  number += rounding;

  // Extract the integer part of the number and print it
  unsigned long int_part = (unsigned long)number;
  double remainder = number - (double)int_part;
  print(int_part);

  // Print the decimal point, but only if there are digits beyond
  if (digits) {
    print('.');
    // Extract digits from the remainder one at a time
    while (digits--) {
      remainder *= 10.0;
      int toPrint = int(remainder);
      print(toPrint);
      remainder -= toPrint;
    }
  }
}

// Preinstantiate
MarlinSerial customizedSerial;

#endif // ARDUINO_ARCH_SAM