c5471_serial.c

這是一個實時嵌入式作業系統 實作了MCS51 ARM等MCU

/****************************************************************************
 * c5471/c5471_serial.c
 *
 *   Copyright (C) 2007, 2008 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <[e-mail]>
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 3. Neither the name NuttX nor the names of its contributors may be
 *    used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <sys/types.h>
#include <unistd.h>
#include <semaphore.h>
#include <string.h>
#include <errno.h>
#include <debug.h>

#include <nuttx/irq.h>
#include <nuttx/arch.h>
#include <nuttx/serial.h>
#include <arch/serial.h>

#include "up_arch.h"
#include "os_internal.h"
#include "up_internal.h"

/****************************************************************************
 * Definitions
 ****************************************************************************/

#define BASE_BAUD     115200

#if defined(CONFIG_UART_IRDA_HWFLOWCONTROL) || defined(CONFIG_UART_MODEM_HWFLOWCONTROL)
# define CONFIG_UART_HWFLOWCONTROL
#endif

/****************************************************************************
 * Private Types
 ****************************************************************************/

struct uart_regs_s
{
  uint32  ier;
  uint32  lcr;
  uint32  fcr;
#ifdef CONFIG_UART_HWFLOWCONTROL
  uint32  efr;
  uint32  tcr;
#endif
};

struct up_dev_s
{
  unsigned int         uartbase;	/* Base address of UART registers */
  unsigned int         baud_base;	/* Base baud for conversions */
  unsigned int         baud;		/* Configured baud */
  ubyte                xmit_fifo_size;	/* Size of transmit FIFO */
  ubyte                irq;		/* IRQ associated with this UART */
  ubyte                parity;		/* 0=none, 1=odd, 2=even */
  ubyte                bits;		/* Number of bits (7 or 8) */
#ifdef CONFIG_UART_HWFLOWCONTROL
  boolean              flowcontrol;	/* TRUE: Hardware flow control
					 * is enabled. */
#endif
  boolean              stopbits2;	/* TRUE: Configure with 2
					 * stop bits instead of 1 */
  struct uart_regs_s   regs;		/* Shadow copy of readonly regs */
};

/****************************************************************************
 * Private Function Prototypes
 ****************************************************************************/

static int     up_setup(struct uart_dev_s *dev);
static void    up_shutdown(struct uart_dev_s *dev);
static int     up_attach(struct uart_dev_s *dev);
static void    up_detach(struct uart_dev_s *dev);
static int     up_interrupt(int irq, void *context);
static int     up_ioctl(struct file *filep, int cmd, unsigned long arg);
static int     up_receive(struct uart_dev_s *dev, unsigned int *status);
static void    up_rxint(struct uart_dev_s *dev, boolean enable);
static boolean up_rxavailable(struct uart_dev_s *dev);
static void    up_send(struct uart_dev_s *dev, int ch);
static void    up_txint(struct uart_dev_s *dev, boolean enable);
static boolean up_txready(struct uart_dev_s *dev);
static boolean up_txempty(struct uart_dev_s *dev);

/****************************************************************************
 * Private Variables
 ****************************************************************************/

struct uart_ops_s g_uart_ops =
{
  .setup          = up_setup,
  .shutdown       = up_shutdown,
  .attach         = up_attach,
  .detach         = up_detach,
  .ioctl          = up_ioctl,
  .receive        = up_receive,
  .rxint          = up_rxint,
  .rxavailable    = up_rxavailable,
  .send           = up_send,
  .txint          = up_txint,
  .txready        = up_txready,
  .txempty        = up_txempty,
};

/* I/O buffers */

static char g_irdarxbuffer[CONFIG_UART_IRDA_RXBUFSIZE];
static char g_irdatxbuffer[CONFIG_UART_IRDA_TXBUFSIZE];
static char g_modemrxbuffer[CONFIG_UART_MODEM_RXBUFSIZE];
static char g_modemtxbuffer[CONFIG_UART_MODEM_TXBUFSIZE];

/* This describes the state of the C5471 serial IRDA port. */

static struct up_dev_s g_irdapriv =
{
  .xmit_fifo_size = UART_IRDA_XMIT_FIFO_SIZE,
  .baud_base      = BASE_BAUD,
  .uartbase       = UART_IRDA_BASE,
  .baud           = CONFIG_UART_IRDA_BAUD,
  .irq            = C5471_IRQ_UART_IRDA,
  .parity         = CONFIG_UART_IRDA_PARITY,
  .bits           = CONFIG_UART_IRDA_BITS,
#ifdef CONFIG_UART_IRDA_HWFLOWCONTROL
  .flowcontrol    = TRUE,
#endif
  .stopbits2      = CONFIG_UART_IRDA_2STOP,
};

static uart_dev_t g_irdaport =
{
  .recv     =
  {
    .size   = CONFIG_UART_IRDA_RXBUFSIZE,
    .buffer = g_irdarxbuffer,
  },
  .xmit     =
  {
    .size   = CONFIG_UART_IRDA_TXBUFSIZE,
    .buffer = g_irdatxbuffer,
   },
  .ops      = &g_uart_ops,
  .priv     = &g_irdapriv,
};

/* This describes the state of the C5471 serial Modem port. */

static struct up_dev_s g_modempriv =
{
  .xmit_fifo_size = UART_XMIT_FIFO_SIZE,
  .baud_base      = BASE_BAUD,
  .uartbase       = UART_MODEM_BASE,
  .baud           = CONFIG_UART_MODEM_BAUD,
  .irq            = C5471_IRQ_UART,
  .parity         = CONFIG_UART_MODEM_PARITY,
  .bits           = CONFIG_UART_MODEM_BITS,
#ifdef CONFIG_UART_MODEM_HWFLOWCONTROL
  .flowcontrol    = TRUE,
#endif
  .stopbits2      = CONFIG_UART_MODEM_2STOP,
};

static uart_dev_t g_modemport =
{
  .recv     =
  {
    .size   = CONFIG_UART_MODEM_RXBUFSIZE,
    .buffer = g_modemrxbuffer,
  },
  .xmit     =
  {
    .size   = CONFIG_UART_MODEM_TXBUFSIZE,
    .buffer = g_modemtxbuffer,
  },
  .ops      = &g_uart_ops,
  .priv     = &g_modempriv,
};

/* Now, which one with be tty0/console and which tty1? */

#ifdef CONFIG_SERIAL_IRDA_CONSOLE
# define CONSOLE_DEV     g_irdaport
# define TTYS0_DEV       g_irdaport
# define TTYS1_DEV       g_modemport
#else
# define CONSOLE_DEV     g_modemport
# define TTYS0_DEV       g_modemport
# define TTYS1_DEV       g_irdaport
#endif

/****************************************************************************
 * Private Functions
 ****************************************************************************/

/****************************************************************************
 * Name: up_inserial
 ****************************************************************************/

static inline uint32 up_inserial(struct up_dev_s *priv, uint32 offset)
{
  return getreg32(priv->uartbase + offset);
}

/****************************************************************************
 * Name: up_serialout
 ****************************************************************************/

static inline void up_serialout(struct up_dev_s *priv, uint32 offset, uint32 value)
{
  putreg32(value, priv->uartbase + offset);
}

/****************************************************************************
 * Name: up_disableuartint
 ****************************************************************************/

static inline void up_disableuartint(struct up_dev_s *priv, uint16 *ier)
{
  if (ier)
    {
      *ier = priv->regs.ier & UART_IER_INTMASK;
    }
  priv->regs.ier &= ~UART_IER_INTMASK;
  up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}

/****************************************************************************
 * Name: up_restoreuartint
 ****************************************************************************/

static inline void up_restoreuartint(struct up_dev_s *priv, uint16 ier)
{
  priv->regs.ier |= ier & (UART_IER_RECVINT|UART_IER_XMITINT);
  up_serialout(priv, UART_IER_OFFS, priv->regs.ier);
}

/****************************************************************************
 * Name: up_waittxready
 ****************************************************************************/

static inline void up_waittxready(struct up_dev_s *priv)
{
  int tmp;

  for (tmp = 1000 ; tmp > 0 ; tmp--)
    {
      if ((up_inserial(priv, UART_SSR_OFFS) & UART_SSR_TXFULL) == 0)
        {
          break;
        }
    }
}
/****************************************************************************
 * Name: up_disablebreaks
 ****************************************************************************/

static inline void up_disablebreaks(struct up_dev_s *priv)
{
  priv->regs.lcr &= ~UART_LCR_BOC;
  up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);
}

/****************************************************************************
 * Name: up_enablebreaks
 ****************************************************************************/

static inline void up_enablebreaks(struct up_dev_s *priv)
{
  priv->regs.lcr |= UART_LCR_BOC;
  up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);
}

/****************************************************************************
 * Name: up_setrate
 ****************************************************************************/

static inline void up_setrate(struct up_dev_s *priv, unsigned int rate)
{
  uint32 div_bit_rate;

  switch (rate)
    {
    case 115200:
      div_bit_rate = BAUD_115200;
      break;
    case 57600:
      div_bit_rate = BAUD_57600;
      break;
    case 38400:
      div_bit_rate = BAUD_38400;
      break;
    case 19200:
      div_bit_rate = BAUD_19200;
      break;
    case 4800:
      div_bit_rate = BAUD_4800;
      break;
    case 2400:
      div_bit_rate = BAUD_2400;
      break;
    case 1200:
      div_bit_rate = BAUD_1200;
      break;
    case 9600:
    default:
      div_bit_rate = BAUD_9600;
      break;
    }

  up_serialout(priv, UART_DIV_BIT_RATE_OFFS, div_bit_rate);
}

/****************************************************************************
 * Name: up_setup
 *
 * Description:
 *   Configure the UART baud, bits, parity, fifos, etc. This
 *   method is called the first time that the serial port is
 *   opened.
 *
 ****************************************************************************/

static int up_setup(struct uart_dev_s *dev)
{
#ifndef CONFIG_SUPPRESS_UART_CONFIG
  struct up_dev_s *priv = dev->priv;
  unsigned int cval;

  if (priv->bits == 7)
    {
      cval = UART_LCR_7BITS;
    }
  else
    {
      cval = UART_LCR_8BITS;
    }

  if (priv->stopbits2)
    {
      cval |= UART_LCR_2STOP;
    }

  if (priv->parity == 1)   /* Odd parity */
    {
      cval |= (UART_LCR_PAREN|UART_LCR_PARODD);
    }
  else if (priv->parity == 2)  /* Even parity */
    {
      cval |= (UART_LCR_PAREN|UART_LCR_PAREVEN);
    }

  /* Both the IrDA and MODEM UARTs support RESET and UART mode. */

  up_serialout(priv, UART_MDR_OFFS, MDR_RESET_MODE);
  up_mdelay(5);
  up_serialout(priv, UART_MDR_OFFS, MDR_UART_MODE);
  up_mdelay(5);

  priv->regs.ier = up_inserial(priv, UART_IER_OFFS);
  priv->regs.lcr = up_inserial(priv, UART_LCR_OFFS);
#ifdef CONFIG_UART_HWFLOWCONTROL
  if (priv->flowcontrol)
    {
      priv->regs.efr = up_inserial(priv, UART_EFR_OFFS);
      priv->regs.tcr = up_inserial(priv, UART_TCR_OFFS);
    }
#endif

  up_disableuartint(priv, NULL);

  up_serialout(priv, UART_EFR_OFFS,  0x0010);           /* Enable fifo control */
  up_serialout(priv, UART_TFCR_OFFS, 0);                /* Reset to 0 */
  up_serialout(priv, UART_RFCR_OFFS, UART_FCR_RX_CLR);  /* Clear RX fifo */
  up_serialout(priv, UART_TFCR_OFFS, UART_FCR_TX_CLR);  /* Clear TX fifo */
  up_serialout(priv, UART_TFCR_OFFS, UART_FCR_FIFO_EN); /* Enable RX/TX fifos */

  up_disablebreaks(priv);

  /* Set the RX and TX trigger levels to the minimum */

  priv->regs.fcr = (priv->regs.fcr & 0xffffffcf) | UART_FCR_FTL;
  up_serialout(priv, UART_RFCR_OFFS, priv->regs.fcr);

  priv->regs.fcr = (priv->regs.fcr & 0xffffff3f) | UART_FCR_FTL;
  up_serialout(priv, UART_RFCR_OFFS, priv->regs.fcr);

  up_setrate(priv, priv->baud);

  priv->regs.lcr &= 0xffffffe0;      /* clear original field, and... */
  priv->regs.lcr |= (uint32)cval;    /* Set new bits in that field. */
  up_serialout(priv, UART_LCR_OFFS, priv->regs.lcr);

#ifdef CONFIG_UART_HWFLOWCONTROL
  if (priv->flowcontrol)
    {
      /* Set the FIFO level triggers for flow control
       * Halt = 48 bytes, resume = 12 bytes
       */

      priv->regs.tcr = (priv->regs.tcr & 0xffffff00) | 0x0000003c;
      up_serialout(priv, UART_TCR_OFFS, priv->regs.tcr);