SOEM/oshw/linux/nicdrv.c

646 lines
20 KiB
C

/*
* Licensed under the GNU General Public License version 2 with exceptions. See
* LICENSE file in the project root for full license information
*/
/** \file
* \brief
* EtherCAT RAW socket driver.
*
* Low level interface functions to send and receive EtherCAT packets.
* EtherCAT has the property that packets are only send by the master,
* and the send packets always return in the receive buffer.
* There can be multiple packets "on the wire" before they return.
* To combine the received packets with the original send packets a buffer
* system is installed. The identifier is put in the index item of the
* EtherCAT header. The index is stored and compared when a frame is received.
* If there is a match the packet can be combined with the transmit packet
* and returned to the higher level function.
*
* The socket layer can exhibit a reversal in the packet order (rare).
* If the Tx order is A-B-C the return order could be A-C-B. The indexed buffer
* will reorder the packets automatically.
*
* The "redundant" option will configure two sockets and two NIC interfaces.
* Slaves are connected to both interfaces, one on the IN port and one on the
* OUT port. Packets are send via both interfaces. Any one of the connections
* (also an interconnect) can be removed and the slaves are still serviced with
* packets. The software layer will detect the possible failure modes and
* compensate. If needed the packets from interface A are resent through interface B.
* This layer if fully transparent for the higher layers.
*/
#include <sys/types.h>
#include <sys/ioctl.h>
#include <net/if.h>
#include <sys/socket.h>
#include <unistd.h>
#include <sys/time.h>
#include <time.h>
#include <arpa/inet.h>
#include <stdio.h>
#include <fcntl.h>
#include <string.h>
#include <netpacket/packet.h>
#include <pthread.h>
#include "oshw.h"
#include "osal.h"
/** Redundancy modes */
enum
{
/** No redundancy, single NIC mode */
ECT_RED_NONE,
/** Double redundant NIC connection */
ECT_RED_DOUBLE
};
/** Primary source MAC address used for EtherCAT.
* This address is not the MAC address used from the NIC.
* EtherCAT does not care about MAC addressing, but it is used here to
* differentiate the route the packet traverses through the EtherCAT
* segment. This is needed to find out the packet flow in redundant
* configurations. */
const uint16 priMAC[3] = { 0x0101, 0x0101, 0x0101 };
/** Secondary source MAC address used for EtherCAT. */
const uint16 secMAC[3] = { 0x0404, 0x0404, 0x0404 };
/** second MAC word is used for identification */
#define RX_PRIM priMAC[1]
/** second MAC word is used for identification */
#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;
}
}
/** Basic setup to connect NIC to socket.
* @param[in] port = port context struct
* @param[in] ifname = Name of NIC device, f.e. "eth0"
* @param[in] secondary = if >0 then use secondary stack instead of primary
* @return >0 if succeeded
*/
int ecx_setupnic(ecx_portt *port, const char *ifname, int secondary)
{
int i;
int r, rval, ifindex;
struct timeval timeout;
struct ifreq ifr;
struct sockaddr_ll sll;
int *psock;
pthread_mutexattr_t mutexattr;
rval = 0;
if (secondary)
{
/* secondary port struct available? */
if (port->redport)
{
/* when using secondary socket it is automatically a redundant setup */
psock = &(port->redport->sockhandle);
*psock = -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_mutexattr_init(&mutexattr);
pthread_mutexattr_setprotocol(&mutexattr , PTHREAD_PRIO_INHERIT);
pthread_mutex_init(&(port->getindex_mutex), &mutexattr);
pthread_mutex_init(&(port->tx_mutex) , &mutexattr);
pthread_mutex_init(&(port->rx_mutex) , &mutexattr);
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]));
psock = &(port->sockhandle);
}
/* we use RAW packet socket, with packet type ETH_P_ECAT */
*psock = socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ECAT));
timeout.tv_sec = 0;
timeout.tv_usec = 1;
r = setsockopt(*psock, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout));
r = setsockopt(*psock, SOL_SOCKET, SO_SNDTIMEO, &timeout, sizeof(timeout));
i = 1;
r = setsockopt(*psock, SOL_SOCKET, SO_DONTROUTE, &i, sizeof(i));
/* connect socket to NIC by name */
strcpy(ifr.ifr_name, ifname);
r = ioctl(*psock, SIOCGIFINDEX, &ifr);
ifindex = ifr.ifr_ifindex;
strcpy(ifr.ifr_name, ifname);
ifr.ifr_flags = 0;
/* reset flags of NIC interface */
r = ioctl(*psock, SIOCGIFFLAGS, &ifr);
/* set flags of NIC interface, here promiscuous and broadcast */
ifr.ifr_flags = ifr.ifr_flags | IFF_PROMISC | IFF_BROADCAST;
r = ioctl(*psock, SIOCSIFFLAGS, &ifr);
/* bind socket to protocol, in this case RAW EtherCAT */
sll.sll_family = AF_PACKET;
sll.sll_ifindex = ifindex;
sll.sll_protocol = htons(ETH_P_ECAT);
r = bind(*psock, (struct sockaddr *)&sll, sizeof(sll));
/* 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));
if (r == 0) rval = 1;
return rval;
}
/** Close sockets used
* @param[in] port = port context struct
* @return 0
*/
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;
}
/** Fill buffer with ethernet header structure.
* Destination MAC is always broadcast.
* Ethertype is always ETH_P_ECAT.
* @param[out] p = buffer
*/
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);
}
/** Get new frame identifier index and allocate corresponding rx buffer.
* @param[in] port = port context struct
* @return new index.
*/
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;
}
/** Set rx buffer status.
* @param[in] port = port context struct
* @param[in] idx = index in buffer array
* @param[in] bufstat = status to set
*/
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;
}
/** Transmit buffer over socket (non blocking).
* @param[in] port = port context struct
* @param[in] idx = index in tx buffer array
* @param[in] stacknumber = 0=Primary 1=Secondary stack
* @return socket send result
*/
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];
(*stack->rxbufstat)[idx] = EC_BUF_TX;
rval = send(*stack->sock, (*stack->txbuf)[idx], lp, 0);
if (rval == -1)
{
(*stack->rxbufstat)[idx] = EC_BUF_EMPTY;
}
return rval;
}
/** Transmit buffer over socket (non blocking).
* @param[in] port = port context struct
* @param[in] idx = index in tx buffer array
* @return socket send result
*/
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 */
port->redport->rxbufstat[idx] = EC_BUF_TX;
if (send(port->redport->sockhandle, &(port->txbuf2), port->txbuflength2 , 0) == -1)
{
port->redport->rxbufstat[idx] = EC_BUF_EMPTY;
}
pthread_mutex_unlock( &(port->tx_mutex) );
}
return rval;
}
/** Non blocking read of socket. Put frame in temporary buffer.
* @param[in] port = port context struct
* @param[in] stacknumber = 0=primary 1=secondary stack
* @return >0 if frame is available and read
*/
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);
port->tempinbufs = bytesrx;
return (bytesrx > 0);
}
/** Non blocking receive frame function. Uses RX buffer and index to combine
* read frame with transmitted frame. To compensate for received frames that
* are out-of-order all frames are stored in their respective indexed buffer.
* If a frame was placed in the buffer previously, the function retrieves it
* from that buffer index without calling ec_recvpkt. If the requested index
* is not already in the buffer it calls ec_recvpkt to fetch it. There are
* three options now, 1 no frame read, so exit. 2 frame read but other
* than requested index, store in buffer and exit. 3 frame read with matching
* index, store in buffer, set completed flag in buffer status and exit.
*
* @param[in] port = port context struct
* @param[in] idx = requested index of frame
* @param[in] stacknumber = 0=primary 1=secondary stack
* @return Workcounter if a frame is found with corresponding index, otherwise
* EC_NOFRAME or EC_OTHERFRAME.
*/
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))
{
rval = EC_OTHERFRAME;
ehp =(ec_etherheadert*)(stack->tempbuf);
/* check if it is an EtherCAT frame */
if (ehp->etype == htons(ETH_P_ECAT))
{
ecp =(ec_comt*)(&(*stack->tempbuf)[ETH_HEADERSIZE]);
l = etohs(ecp->elength) & 0x0fff;
idxf = ecp->index;
/* found index equals requested index ? */
if (idxf == idx)
{
/* yes, put it in the buffer array (strip ethernet header) */
memcpy(rxbuf, &(*stack->tempbuf)[ETH_HEADERSIZE], (*stack->txbuflength)[idx] - ETH_HEADERSIZE);
/* 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;
}
/** Blocking redundant receive frame function. If redundant mode is not active then
* it skips the secondary stack and redundancy functions. In redundant mode it waits
* for both (primary and secondary) frames to come in. The result goes in an decision
* tree that decides, depending on the route of the packet and its possible missing arrival,
* how to reroute the original packet to get the data in an other try.
*
* @param[in] port = port context struct
* @param[in] idx = requested index of frame
* @param[in] timer = absolute timeout time
* @return Workcounter if a frame is found with corresponding index, otherwise
* EC_NOFRAME.
*/
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;
}
/** Blocking receive frame function. Calls ec_waitinframe_red().
* @param[in] port = port context struct
* @param[in] idx = requested index of frame
* @param[in] timeout = timeout in us
* @return Workcounter if a frame is found with corresponding index, otherwise
* EC_NOFRAME.
*/
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;
}
/** Blocking send and receive frame function. Used for non processdata frames.
* A datagram is build into a frame and transmitted via this function. It waits
* for an answer and returns the workcounter. The function retries if time is
* left and the result is WKC=0 or no frame received.
*
* The function calls ec_outframe_red() and ec_waitinframe_red().
*
* @param[in] port = port context struct
* @param[in] idx = index of frame
* @param[in] timeout = timeout in us
* @return Workcounter or EC_NOFRAME
*/
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