rtems/nicdrv.c

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/*
 * Licensed under the GNU General Public License version 2 with exceptions. See
 * LICENSE file in the project root for full license information
 */

#include <sys/time.h>
#include <time.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <net/bpf.h>
#include <sys/socket.h>
#include <net/if.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <pthread.h>
#include <assert.h>

#include "oshw.h"
#include "osal.h"

enum
{
   ECT_RED_NONE,
   ECT_RED_DOUBLE
};


const uint16 priMAC[3] = { 0x0201, 0x0101, 0x0101 };
const uint16 secMAC[3] = { 0x0604, 0x0404, 0x0404 };

#define RX_PRIM priMAC[1]

#define RX_SEC secMAC[1]

static void ecx_clear_rxbufstat(int *rxbufstat)
{
   int i;
   for(i = 0; i < EC_MAXBUF; i++)
   {
      rxbufstat[i] = EC_BUF_EMPTY;
   }
}

int ecx_setupnic(ecx_portt *port, const char *ifname, int secondary)
{
   int i;
   int r, rval;
   struct timeval timeout;
   struct ifreq ifr;
   int *bpf;
   // const uint8_t bpffnamelen = 12;
   char fname[13] = {0};
   const int maxbpffile = 1000;
   uint true_val = 1;

   rval = 0;
   if (secondary)
   {
      /* secondary port struct available? */
      if (port->redport)
      {
         /* when using secondary socket it is automatically a redundant setup */
         bpf = &(port->redport->sockhandle);
         *bpf = -1;
         port->redstate                   = ECT_RED_DOUBLE;
         port->redport->stack.sock        = &(port->redport->sockhandle);
         port->redport->stack.txbuf       = &(port->txbuf);
         port->redport->stack.txbuflength = &(port->txbuflength);
         port->redport->stack.tempbuf     = &(port->redport->tempinbuf);
         port->redport->stack.rxbuf       = &(port->redport->rxbuf);
         port->redport->stack.rxbufstat   = &(port->redport->rxbufstat);
         port->redport->stack.rxsa        = &(port->redport->rxsa);
         ecx_clear_rxbufstat(&(port->redport->rxbufstat[0]));
      }
      else
      {
         /* fail */
         return 0;
      }
   }
   else
   {
      pthread_mutex_init(&(port->getindex_mutex), NULL);
      pthread_mutex_init(&(port->tx_mutex)      , NULL);
      pthread_mutex_init(&(port->rx_mutex)      , NULL);
      port->sockhandle        = -1;
      port->lastidx           = 0;
      port->redstate          = ECT_RED_NONE;
      port->stack.sock        = &(port->sockhandle);
      port->stack.txbuf       = &(port->txbuf);
      port->stack.txbuflength = &(port->txbuflength);
      port->stack.tempbuf     = &(port->tempinbuf);
      port->stack.rxbuf       = &(port->rxbuf);
      port->stack.rxbufstat   = &(port->rxbufstat);
      port->stack.rxsa        = &(port->rxsa);
      ecx_clear_rxbufstat(&(port->rxbufstat[0]));
      bpf = &(port->sockhandle);
   }

   /* Open a bpf file descriptor */
   *bpf = -1;
   for(i = 0; *bpf == -1 && i < maxbpffile; ++i)
   {
     sprintf(fname, "/dev/bpf%i", i);
     *bpf = open(fname, O_RDWR);
   }

   if(*bpf == -1)
   {
     /* Failed to open bpf */
     perror("Could not open bpf\n");
     return 0;
   }

   /* Need to hand the same buffer size as bpf expects,
      force bpf to use our buffer size! */
   uint buffer_len = sizeof(ec_bufT);
   if (ioctl(*bpf, BIOCSBLEN, &buffer_len) == -1) {
     perror("BIOCGBLEN");
   }
   
   if (buffer_len < 1518) {
     printf("buffer_len %d < 1518\n", buffer_len);
     return 0;
   }

   /* connect bpf to NIC by name */
   strcpy(ifr.ifr_name, ifname);
   if(ioctl(*bpf, BIOCSETIF, &ifr) == -1) {
     perror("BIOCSETIF");
     return 0;
   }

   /* Set required bpf options */

   /* Activate immediate mode */
   if (ioctl(*bpf, BIOCIMMEDIATE, &true_val) == -1) {
     perror("BIOCIMMEDIATE");
     return 0;
   }

   /* Set interface in promiscuous mode */
   if (ioctl(*bpf, BIOCPROMISC, &true_val) == -1) {
     perror("BIOCPROMISC");
     return 0;
   }
   
   /* Allow to have custom source address */
   if (ioctl(*bpf, BIOCSHDRCMPLT, &true_val) == -1) {
     perror("BIOCSHDRCMPLT");
     return 0;
   }

   /* Listen only to incomming messages */
   uint direction = BPF_D_IN;
   if (ioctl(*bpf, BIOCSDIRECTION, &direction) == -1) {
     perror("BIOCSDIRECTION");
     return 0;
   }

   /* Set read timeout */
   timeout.tv_sec =  0;
   timeout.tv_usec = 11000;
   if (ioctl(*bpf, BIOCSRTIMEOUT, &timeout) == -1) {
     perror("BIOCSRTIMEOUT");
     return 0;
   }

   /* setup ethernet headers in tx buffers so we don't have to repeat it */
   for (i = 0; i < EC_MAXBUF; i++)
   {
      ec_setupheader(&(port->txbuf[i]));
      port->rxbufstat[i] = EC_BUF_EMPTY;
   }
   ec_setupheader(&(port->txbuf2));

   return 1;
}

int ecx_closenic(ecx_portt *port)
{
   if (port->sockhandle >= 0)
      close(port->sockhandle);
   if ((port->redport) && (port->redport->sockhandle >= 0))
      close(port->redport->sockhandle);

   return 0;
}

void ec_setupheader(void *p)
{
   ec_etherheadert *bp;
   bp = p;
   bp->da0 = htons(0xffff);
   bp->da1 = htons(0xffff);
   bp->da2 = htons(0xffff);
   bp->sa0 = htons(priMAC[0]);
   bp->sa1 = htons(priMAC[1]);
   bp->sa2 = htons(priMAC[2]);
   bp->etype = htons(ETH_P_ECAT);
}

int ecx_getindex(ecx_portt *port)
{
   int idx;
   int cnt;

   pthread_mutex_lock( &(port->getindex_mutex) );

   idx = port->lastidx + 1;
   /* index can't be larger than buffer array */
   if (idx >= EC_MAXBUF)
   {
      idx = 0;
   }
   cnt = 0;
   /* try to find unused index */
   while ((port->rxbufstat[idx] != EC_BUF_EMPTY) && (cnt < EC_MAXBUF))
   {
      idx++;
      cnt++;
      if (idx >= EC_MAXBUF)
      {
         idx = 0;
      }
   }
   port->rxbufstat[idx] = EC_BUF_ALLOC;
   if (port->redstate != ECT_RED_NONE)
      port->redport->rxbufstat[idx] = EC_BUF_ALLOC;
   port->lastidx = idx;

   pthread_mutex_unlock( &(port->getindex_mutex) );

   return idx;
}

void ecx_setbufstat(ecx_portt *port, int idx, int bufstat)
{
   port->rxbufstat[idx] = bufstat;
   if (port->redstate != ECT_RED_NONE)
      port->redport->rxbufstat[idx] = bufstat;
}

int ecx_outframe(ecx_portt *port, int idx, int stacknumber)
{
   int lp, rval;
   ec_stackT *stack;

   if (!stacknumber)
   {
      stack = &(port->stack);
   }
   else
   {
      stack = &(port->redport->stack);
   }
   lp = (*stack->txbuflength)[idx];
   //rval = send(*stack->sock, (*stack->txbuf)[idx], lp, 0);
   (*stack->rxbufstat)[idx] = EC_BUF_TX;
   rval = write (*stack->sock,(*stack->txbuf)[idx], lp);
   if (rval == -1)
   {
      (*stack->rxbufstat)[idx] = EC_BUF_EMPTY;
   }

   return rval;
}

int ecx_outframe_red(ecx_portt *port, int idx)
{
   ec_comt *datagramP;
   ec_etherheadert *ehp;
   int rval;

   ehp = (ec_etherheadert *)&(port->txbuf[idx]);
   /* rewrite MAC source address 1 to primary */
   ehp->sa1 = htons(priMAC[1]);
   /* transmit over primary socket*/
   rval = ecx_outframe(port, idx, 0);
   if (port->redstate != ECT_RED_NONE)
   {
      pthread_mutex_lock( &(port->tx_mutex) );
      ehp = (ec_etherheadert *)&(port->txbuf2);
      /* use dummy frame for secondary socket transmit (BRD) */
      datagramP = (ec_comt*)&(port->txbuf2[ETH_HEADERSIZE]);
      /* write index to frame */
      datagramP->index = idx;
      /* rewrite MAC source address 1 to secondary */
      ehp->sa1 = htons(secMAC[1]);
      /* transmit over secondary socket */
      //send(port->redport->sockhandle, &(port->txbuf2), port->txbuflength2 , 0);
      port->redport->rxbufstat[idx] = EC_BUF_TX;
      if (write(port->redport->sockhandle, &(port->txbuf2), port->txbuflength2) == -1)
      {
         (*stack->rxbufstat)[idx] = EC_BUF_EMPTY;
      }
      pthread_mutex_unlock( &(port->tx_mutex) );
   }

   return rval;
}

static int ecx_recvpkt(ecx_portt *port, int stacknumber)
{
   int lp, bytesrx;
   ec_stackT *stack;

   if (!stacknumber)
   {
      stack = &(port->stack);
   }
   else
   {
      stack = &(port->redport->stack);
   }
   lp = sizeof(port->tempinbuf);
   //bytesrx = recv(*stack->sock, (*stack->tempbuf), lp, 0);
   bytesrx = read(*stack->sock, (*stack->tempbuf), lp);
   port->tempinbufs = bytesrx;

   return (bytesrx > 0);
}

int ecx_inframe(ecx_portt *port, int idx, int stacknumber)
{
   uint16  l;
   int     rval;
   int     idxf;
   ec_etherheadert *ehp;
   ec_comt *ecp;
   ec_stackT *stack;
   ec_bufT *rxbuf;

   if (!stacknumber)
   {
      stack = &(port->stack);
   }
   else
   {
      stack = &(port->redport->stack);
   }
   rval = EC_NOFRAME;
   rxbuf = &(*stack->rxbuf)[idx];
   /* check if requested index is already in buffer ? */
   if ((idx < EC_MAXBUF) && ((*stack->rxbufstat)[idx] == EC_BUF_RCVD))
   {
      l = (*rxbuf)[0] + ((uint16)((*rxbuf)[1] & 0x0f) << 8);
      /* return WKC */
      rval = ((*rxbuf)[l] + ((uint16)(*rxbuf)[l + 1] << 8));
      /* mark as completed */
      (*stack->rxbufstat)[idx] = EC_BUF_COMPLETE;
   }
   else
   {
      pthread_mutex_lock(&(port->rx_mutex));
      /* non blocking call to retrieve frame from socket */
      if (ecx_recvpkt(port, stacknumber))
      {
         /* The data read from /dev/bpf includes an extra header, skip it. */
         struct bpf_hdr *bpfh = (struct bpf_hdr *)(stack->tempbuf);
         rval = EC_OTHERFRAME;
         ehp =(ec_etherheadert*)(*stack->tempbuf + bpfh->bh_hdrlen);
         /* check if it is an EtherCAT frame */
         if (ehp->etype == htons(ETH_P_ECAT))
         {
            /* The EtherCAT header follows the ethernet frame header. */
            ecp =(ec_comt*)(&ehp[1]);
            l = etohs(ecp->elength) & 0x0fff;
            idxf = ecp->index;
            /* found index equals requested index ? */
            if (idxf == idx)
            {
               /* yes, put it in the buffer array (strip headers) */
               memcpy(rxbuf, &(ehp[1]), port->tempinbufs - ((uint32_t)ecp - (uint32_t)*stack->tempbuf));
               /* return WKC */
               rval = ((*rxbuf)[l] + ((uint16)((*rxbuf)[l + 1]) << 8));
               /* mark as completed */
               (*stack->rxbufstat)[idx] = EC_BUF_COMPLETE;
               /* store MAC source word 1 for redundant routing info */
               (*stack->rxsa)[idx] = ntohs(ehp->sa1);
            }
            else
            {
               /* check if index exist and someone is waiting for it */
               if (idxf < EC_MAXBUF && (*stack->rxbufstat)[idxf] == EC_BUF_TX)
               {
                  rxbuf = &(*stack->rxbuf)[idxf];
                  /* put it in the buffer array (strip ethernet header) */
                  memcpy(rxbuf, &(*stack->tempbuf)[ETH_HEADERSIZE], (*stack->txbuflength)[idxf] - ETH_HEADERSIZE);
                  /* mark as received */
                  (*stack->rxbufstat)[idxf] = EC_BUF_RCVD;
                  (*stack->rxsa)[idxf] = ntohs(ehp->sa1);
               }
               else
               {
                  /* strange things happened */
               }
            }
         }
      }
      pthread_mutex_unlock( &(port->rx_mutex) );

   }

   /* WKC if matching frame found */
   return rval;
}

static int ecx_waitinframe_red(ecx_portt *port, int idx, osal_timert *timer)
{
   osal_timert timer2;
   int wkc  = EC_NOFRAME;
   int wkc2 = EC_NOFRAME;
   int primrx, secrx;

   /* if not in redundant mode then always assume secondary is OK */
   if (port->redstate == ECT_RED_NONE)
      wkc2 = 0;
   do
   {
      /* only read frame if not already in */
      if (wkc <= EC_NOFRAME)
         wkc  = ecx_inframe(port, idx, 0);
      /* only try secondary if in redundant mode */
      if (port->redstate != ECT_RED_NONE)
      {
         /* only read frame if not already in */
         if (wkc2 <= EC_NOFRAME)
            wkc2 = ecx_inframe(port, idx, 1);
      }
   /* wait for both frames to arrive or timeout */
   } while (((wkc <= EC_NOFRAME) || (wkc2 <= EC_NOFRAME)) && !osal_timer_is_expired(timer));
   /* only do redundant functions when in redundant mode */
   if (port->redstate != ECT_RED_NONE)
   {
      /* primrx if the received MAC source on primary socket */
      primrx = 0;
      if (wkc > EC_NOFRAME) primrx = port->rxsa[idx];
      /* secrx if the received MAC source on psecondary socket */
      secrx = 0;
      if (wkc2 > EC_NOFRAME) secrx = port->redport->rxsa[idx];

      /* primary socket got secondary frame and secondary socket got primary frame */
      /* normal situation in redundant mode */
      if ( ((primrx == RX_SEC) && (secrx == RX_PRIM)) )
      {
         /* copy secondary buffer to primary */
         memcpy(&(port->rxbuf[idx]), &(port->redport->rxbuf[idx]), port->txbuflength[idx] - ETH_HEADERSIZE);
         wkc = wkc2;
      }
      /* primary socket got nothing or primary frame, and secondary socket got secondary frame */
      /* we need to resend TX packet */
      if ( ((primrx == 0) && (secrx == RX_SEC)) ||
           ((primrx == RX_PRIM) && (secrx == RX_SEC)) )
      {
         /* If both primary and secondary have partial connection retransmit the primary received
          * frame over the secondary socket. The result from the secondary received frame is a combined
          * frame that traversed all slaves in standard order. */
         if ( (primrx == RX_PRIM) && (secrx == RX_SEC) )
         {
            /* copy primary rx to tx buffer */
            memcpy(&(port->txbuf[idx][ETH_HEADERSIZE]), &(port->rxbuf[idx]), port->txbuflength[idx] - ETH_HEADERSIZE);
         }
         osal_timer_start (&timer2, EC_TIMEOUTRET);
         /* resend secondary tx */
         ecx_outframe(port, idx, 1);
         do
         {
            /* retrieve frame */
            wkc2 = ecx_inframe(port, idx, 1);
         } while ((wkc2 <= EC_NOFRAME) && !osal_timer_is_expired(&timer2));
         if (wkc2 > EC_NOFRAME)
         {
            /* copy secondary result to primary rx buffer */
            memcpy(&(port->rxbuf[idx]), &(port->redport->rxbuf[idx]), port->txbuflength[idx] - ETH_HEADERSIZE);
            wkc = wkc2;
         }
      }
   }

   /* return WKC or EC_NOFRAME */
   return wkc;
}

int ecx_waitinframe(ecx_portt *port, int idx, int timeout)
{
   int wkc;
   osal_timert timer;

   osal_timer_start (&timer, timeout);
   wkc = ecx_waitinframe_red(port, idx, &timer);

   return wkc;
}

int ecx_srconfirm(ecx_portt *port, int idx, int timeout)
{
   int wkc = EC_NOFRAME;
   osal_timert timer1, timer2;

   osal_timer_start (&timer1, timeout);
   do
   {
      /* tx frame on primary and if in redundant mode a dummy on secondary */
      ecx_outframe_red(port, idx);
      if (timeout < EC_TIMEOUTRET)
      {
         osal_timer_start (&timer2, timeout);
      }
      else
      {
         /* normally use partial timeout for rx */
         osal_timer_start (&timer2, EC_TIMEOUTRET);
      }
      /* get frame from primary or if in redundant mode possibly from secondary */
      wkc = ecx_waitinframe_red(port, idx, &timer2);
   /* wait for answer with WKC>=0 or otherwise retry until timeout */
   } while ((wkc <= EC_NOFRAME) && !osal_timer_is_expired (&timer1));

   return wkc;
}

#ifdef EC_VER1
int ec_setupnic(const char *ifname, int secondary)
{
   return ecx_setupnic(&ecx_port, ifname, secondary);
}

int ec_closenic(void)
{
   return ecx_closenic(&ecx_port);
}

int ec_getindex(void)
{
   return ecx_getindex(&ecx_port);
}

void ec_setbufstat(int idx, int bufstat)
{
   ecx_setbufstat(&ecx_port, idx, bufstat);
}

int ec_outframe(int idx, int stacknumber)
{
   return ecx_outframe(&ecx_port, idx, stacknumber);
}

int ec_outframe_red(int idx)
{
   return ecx_outframe_red(&ecx_port, idx);
}

int ec_inframe(int idx, int stacknumber)
{
   return ecx_inframe(&ecx_port, idx, stacknumber);
}

int ec_waitinframe(int idx, int timeout)
{
   return ecx_waitinframe(&ecx_port, idx, timeout);
}

int ec_srconfirm(int idx, int timeout)
{
   return ecx_srconfirm(&ecx_port, idx, timeout);
}
#endif