skeleton.c

這是一個實時嵌入式作業系統 實作了MCS51 ARM等MCU

 ****************************************************************************/

static void skel_txdone(struct skel_driver_s *skel)
{
  /* Check for errors and update statistics */

  /* If no further xmits are pending, then cancel the TX timeout */

  wd_cancel(skel->sk_txtimeout);

  /* Then poll uIP for new XMIT data */

  (void)uip_poll(&skel->sk_dev, skel_uiptxpoll);
}

/****************************************************************************
 * Function: skel_interrupt
 *
 * Description:
 *   Hardware interrupt handler
 *
 * Parameters:
 *   irq     - Number of the IRQ that generated the interrupt
 *   context - Interrupt register state save info (architecture-specific)
 *
 * Returned Value:
 *   OK on success
 *
 * Assumptions:
 *
 ****************************************************************************/

static int skel_interrupt(int irq, FAR void *context)
{
  register struct skel_driver_s *skel = &g_skel[0];

  /* Disable Ethernet interrupts */

  /* Get and clear interrupt status bits */

  /* Handle interrupts according to status bit settings */

  /* Check if we received an incoming packet, if so, call skel_receive() */

  skel_receive(skel);

  /* Check is a packet transmission just completed.  If so, call skel_txdone */

  skel_txdone(skel);

  /* Enable Ethernet interrupts (perhaps excluding the TX done interrupt if 
   * there are no pending transmissions.
   */

  return OK;
}

/****************************************************************************
 * Function: skel_txtimeout
 *
 * Description:
 *   Our TX watchdog timed out.  Called from the timer interrupt handler.
 *   The last TX never completed.  Reset the hardware and start again.
 *
 * Parameters:
 *   argc - The number of available arguments
 *   arg  - The first argument
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static void skel_txtimeout(int argc, uint32 arg, ...)
{
  struct skel_driver_s *skel = (struct skel_driver_s *)arg;

  /* Increment statistics and dump debug info */

  /* Then reset the hardware */

  /* Then poll uIP for new XMIT data */

  (void)uip_poll(&skel->sk_dev, skel_uiptxpoll);
}

/****************************************************************************
 * Function: skel_polltimer
 *
 * Description:
 *   Periodic timer handler.  Called from the timer interrupt handler.
 *
 * Parameters:
 *   argc - The number of available arguments
 *   arg  - The first argument
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static void skel_polltimer(int argc, uint32 arg, ...)
{
  struct skel_driver_s *skel = (struct skel_driver_s *)arg;

  /* Check if there is room in the send another TXr packet.  */

  /* If so, update TCP timing states and poll uIP for new XMIT data */

  (void)uip_timer(&skel->sk_dev, skel_uiptxpoll, skeleton_POLLHSEC);

  /* Setup the watchdog poll timer again */

  (void)wd_start(skel->sk_txpoll, skeleton_WDDELAY, skel_polltimer, 1, arg);
}

/****************************************************************************
 * Function: skel_ifup
 *
 * Description:
 *   NuttX Callback: Bring up the Ethernet interface when an IP address is
 *   provided 
 *
 * Parameters:
 *   dev  - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static int skel_ifup(struct uip_driver_s *dev)
{
  struct skel_driver_s *skel = (struct skel_driver_s *)dev->d_private;

  ndbg("Bringing up: %d.%d.%d.%d\n",
       dev->d_ipaddr & 0xff, (dev->d_ipaddr >> 8) & 0xff,
       (dev->d_ipaddr >> 16) & 0xff, dev->d_ipaddr >> 24 );

  /* Initilize Ethernet interface */

  /* Set and activate a timer process */

  (void)wd_start(skel->sk_txpoll, skeleton_WDDELAY, skel_polltimer, 1, (uint32)skel);

  /* Enable the Ethernet interrupt */

  skel->sk_bifup = TRUE;
  up_enable_irq(CONFIG_skeleton_IRQ);
  return OK;
}

/****************************************************************************
 * Function: skel_ifdown
 *
 * Description:
 *   NuttX Callback: Stop the interface.
 *
 * Parameters:
 *   dev  - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *
 ****************************************************************************/

static int skel_ifdown(struct uip_driver_s *dev)
{
  struct skel_driver_s *skel = (struct skel_driver_s *)dev->d_private;
  irqstate_t flags;

  /* Disable the Ethernet interrupt */

  flags = irqsave();
  up_disable_irq(CONFIG_skeleton_IRQ);

  /* Cancel the TX poll timer and TX timeout timers */

  wd_cancel(skel->sk_txpoll);
  wd_cancel(skel->sk_txtimeout);

  /* Reset the device */

  skel->sk_bifup = FALSE;
  irqrestore(flags);
  return OK;
}

/****************************************************************************
 * Function: skel_txavail
 *
 * Description:
 *   Driver callback invoked when new TX data is available.  This is a 
 *   stimulus perform an out-of-cycle poll and, thereby, reduce the TX
 *   latency.
 *
 * Parameters:
 *   dev  - Reference to the NuttX driver state structure
 *
 * Returned Value:
 *   None
 *
 * Assumptions:
 *   Called in normal user mode
 *
 ****************************************************************************/

static int skel_txavail(struct uip_driver_s *dev)
{
  struct skel_driver_s *skel = (struct skel_driver_s *)dev->d_private;
  irqstate_t flags;

  flags = irqsave();

  /* Ignore the notification if the interface is not yet up */

  if (skel->sk_bifup)
    {

      /* Check if there is room in the hardware to hold another outgoing packet. */

      /* If so, then poll uIP for new XMIT data */

      (void)uip_poll(&skel->sk_dev, skel_uiptxpoll);
    }

  irqrestore(flags);
  return OK;
}

/****************************************************************************
 * Public Functions
 ****************************************************************************/

/****************************************************************************
 * Function: skel_initialize
 *
 * Description:
 *   Initialize the Ethernet driver
 *
 * Parameters:
 *   None
 *
 * Returned Value:
 *   OK on success; Negated errno on failure.
 *
 * Assumptions:
 *
 ****************************************************************************/

/* Initialize the DM90x0 chip and driver */

int skel_initialize(void)
{
  /* Check if a Ethernet chip is recognized at its I/O base */

  /* Attach the IRQ to the driver */

  if (irq_attach(CONFIG_skeleton_IRQ, skel_interrupt))
    {
      /* We could not attach the ISR to the ISR */

      return -EAGAIN;
    }

  /* Initialize the driver structure */

  memset(g_skel, 0, CONFIG_skeleton_NINTERFACES*sizeof(struct skel_driver_s));
  g_skel[0].sk_dev.d_ifup    = skel_ifup;     /* I/F down callback */
  g_skel[0].sk_dev.d_ifdown  = skel_ifdown;   /* I/F up (new IP address) callback */
  g_skel[0].sk_dev.d_txavail = skel_txavail;  /* New TX data callback */
  g_skel[0].sk_dev.d_private = (void*)g_skel; /* Used to recover private state from dev */

  /* Create a watchdog for timing polling for and timing of transmisstions */

  g_skel[0].sk_txpoll       = wd_create();   /* Create periodic poll timer */
  g_skel[0].sk_txtimeout    = wd_create();   /* Create TX timeout timer */

  /* Read the MAC address from the hardware into g_skel[0].sk_dev.d_mac.ether_addr_octet */

  /* Register the device with the OS so that socket IOCTLs can be performed */

  (void)netdev_register(&g_skel[0].sk_dev);
  return OK;
}

#endif /* CONFIG_NET && CONFIG_skeleton_NET */