fixed collisions, kludge local send and broadcast

SCCS-vsn: sys/vax/if/if_ec.c 4.5

diff --git a/usr/src/sys/vax/if/if_ec.c b/usr/src/sys/vax/if/if_ec.c
index 33f918e..7c3794e 100644 (file)
--- a/usr/src/sys/vax/if/if_ec.c
+++ b/usr/src/sys/vax/if/if_ec.c
@@ -1,7 +1,8 @@
-/*     if_ec.c 4.4     82/04/12        */
+/*     if_ec.c 4.5     82/04/14        */

 
 #include "ec.h"
 #include "imp.h"
 
 #include "ec.h"
 #include "imp.h"

+#include "loop.h"

 
 /*
  * 3Com Ethernet Controller interface
 
 /*
  * 3Com Ethernet Controller interface


@@ -43,6 +44,8 @@ struct        uba_driver ecdriver =
 int    ecinit(),ecoutput(),ecreset();
 struct mbuf *ecget();
 
 int    ecinit(),ecoutput(),ecreset();
 struct mbuf *ecget();
 

+extern struct ifnet loif;
+

 /*
  * Ethernet software status per interface.
  *
 /*
  * Ethernet software status per interface.
  *


@@ -58,9 +61,9 @@ struct mbuf *ecget();
 struct ec_softc {
        struct  ifnet es_if;            /* network-visible interface */
        struct  ifuba es_ifuba;         /* UNIBUS resources */
 struct ec_softc {
        struct  ifnet es_if;            /* network-visible interface */
        struct  ifuba es_ifuba;         /* UNIBUS resources */

-       short   es_delay;               /* current output delay */

        short   es_mask;                /* mask for current output delay */
 #ifdef notdef
        short   es_mask;                /* mask for current output delay */
 #ifdef notdef

+       short   es_delay;               /* current output delay */

        long    es_lastx;               /* host last transmitted to */
 #endif
        short   es_oactive;             /* is output active? */
        long    es_lastx;               /* host last transmitted to */
 #endif
        short   es_oactive;             /* is output active? */


@@ -249,7 +252,7 @@ int enlastmask = (~0) << 5;
 /*
  * Start or restart output on interface.
  * If interface is already active, then this is a retransmit
 /*
  * Start or restart output on interface.
  * If interface is already active, then this is a retransmit

- * after a collision, and just restuff registers and delay.
+ * after a collision, and just restuff registers.

  * If interface is not already active, get another datagram
  * to send off of the interface queue, and map it to the interface
  * before starting the output.
  * If interface is not already active, get another datagram
  * to send off of the interface queue, and map it to the interface
  * before starting the output.


@@ -327,7 +330,6 @@ COUNT(ECXINT);
                printf("ec%d: strange xmit interrupt!\n", unit);
        es->es_if.if_opackets++;
        es->es_oactive = 0;
                printf("ec%d: strange xmit interrupt!\n", unit);
        es->es_if.if_opackets++;
        es->es_oactive = 0;

-       es->es_delay = 0;

        es->es_mask = ~0;
        addr->ec_xcr = EC_XCLR;
        /*
        es->es_mask = ~0;
        addr->ec_xcr = EC_XCLR;
        /*


@@ -357,7 +359,7 @@ eccollide(unit)
        struct ec_softc *es = &ec_softc[unit];
 COUNT(ECCOLLIDE);
 
        struct ec_softc *es = &ec_softc[unit];
 COUNT(ECCOLLIDE);
 

-       printf("ec%d: eccollide\n", unit);
+       printf("ec%d: collision\n", unit);

        es->es_if.if_collisions++;
        if (es->es_oactive == 0)
                return;
        es->es_if.if_collisions++;
        if (es->es_oactive == 0)
                return;


@@ -368,6 +370,10 @@ ecdocoll(unit)
        int unit;
 {
        register struct ec_softc *es = &ec_softc[unit];
        int unit;
 {
        register struct ec_softc *es = &ec_softc[unit];

+       register struct ecdevice *addr =
+           (struct ecdevice *)ecinfo[unit]->ui_addr;
+       register i;
+       int delay;

 
        /*
         * Es_mask is a 16 bit number with n low zero bits, with
 
        /*
         * Es_mask is a 16 bit number with n low zero bits, with


@@ -375,24 +381,39 @@ ecdocoll(unit)
         * backed off 16 times, and give up.
         */
        if (es->es_mask == 0) {
         * backed off 16 times, and give up.
         */
        if (es->es_mask == 0) {

+               es->es_if.if_oerrors++;

                printf("ec%d: send error\n", unit);
                /*
                printf("ec%d: send error\n", unit);
                /*

-                * this makes enxint wrong.  fix later.
+                * Reset interface, then requeue rcv buffers.
+                * Some incoming packets may be lost, but that
+                * can't be helped.
+                */
+               addr->ec_xcr = EC_UECLR;
+               for (i=ECRHBF; i>=ECRLBF; i--)
+                       addr->ec_rcr = EC_READ|i;
+               /*
+                * Reset and transmit next packet (if any).

                 */
                 */

-               ecxint(unit);
+               es->es_oactive = 0;
+               es->es_mask = ~0;
+               if (es->es_if.if_snd.ifq_head)
+                       ecstart(unit);

                return;
        }
        /*
                return;
        }
        /*

-        * Another backoff.  Restart with delay based on n low bits
-        * of the interval timer.
+        * Do exponential backoff.  Compute delay based on low bits
+        * of the interval timer.  Then delay for that number of
+        * slot times.  A slot time is 51.2 microseconds (rounded to 51).
+        * This does not take into account the time already used to
+        * process the interrupt.

         */
        es->es_mask <<= 1;
         */
        es->es_mask <<= 1;

-       es->es_delay = mfpr(ICR) &~ es->es_mask;
+       delay = mfpr(ICR) &~ es->es_mask;
+       DELAY(delay * 51);

        /*
        /*

-        * This should do some sort of delay before calling ecstart.
-        * I'll figure this out later.
+        * Clear the controller's collision flag, thus enabling retransmit.

         */
         */

-       ecstart(unit);
+       addr->ec_xcr = EC_JCLR;

 }
 
 #ifdef notdef
 }
 
 #ifdef notdef


@@ -442,7 +463,7 @@ COUNT(ECREAD);
                panic("ecrint");
        ecbuf = es->es_buf[buf];
        ecoff = *(short *)ecbuf;
                panic("ecrint");
        ecbuf = es->es_buf[buf];
        ecoff = *(short *)ecbuf;

-       if (ecoff <= ECRDOFF || ecoff > ECMTU+ECRDOFF) {
+       if (ecoff <= ECRDOFF || ecoff > 2046) {

                es->es_if.if_ierrors++;
 #ifdef notdef
                if (es->es_if.if_ierrors % 100 == 0)
                es->es_if.if_ierrors++;
 #ifdef notdef
                if (es->es_if.if_ierrors % 100 == 0)


@@ -535,6 +556,9 @@ setup:
  * Encapsulate a packet of type family for the local net.
  * Use trailer local net encapsulation if enough data in first
  * packet leaves a multiple of 512 bytes of data in remainder.
  * Encapsulate a packet of type family for the local net.
  * Use trailer local net encapsulation if enough data in first
  * packet leaves a multiple of 512 bytes of data in remainder.

+ * If destination is this address or broadcast, send packet to
+ * loop device to kludge around the fact that 3com interfaces can't
+ * talk to themselves.

  */
 ecoutput(ifp, m0, dst)
        struct ifnet *ifp;
  */
 ecoutput(ifp, m0, dst)
        struct ifnet *ifp;


@@ -547,6 +571,7 @@ ecoutput(ifp, m0, dst)
        register struct ec_header *ec;
        register int off;
        register int i;
        register struct ec_header *ec;
        register int off;
        register int i;

+       struct mbuf *mcopy = (struct mbuf *) 0;         /* Null */

 
 COUNT(ECOUTPUT);
        switch (dst->sa_family) {
 
 COUNT(ECOUTPUT);
        switch (dst->sa_family) {


@@ -554,6 +579,13 @@ COUNT(ECOUTPUT);
 #ifdef INET
        case AF_INET:
                dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr;
 #ifdef INET
        case AF_INET:
                dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr;

+               if ((dest &~ 0xff) == 0)
+                       mcopy = m_copy(m, 0, M_COPYALL);
+               else if (dest == ((struct sockaddr_in *)&es->es_if.if_addr)->
+                   sin_addr.s_addr) {
+                       mcopy = m;
+                       goto gotlocal;
+               }

                off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
                if (off > 0 && (off & 0x1ff) == 0 &&
                    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {
                off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len;
                if (off > 0 && (off & 0x1ff) == 0 &&
                    m->m_off >= MMINOFF + 2 * sizeof (u_short)) {


@@ -646,7 +678,11 @@ gottype:
        if (es->es_oactive == 0)
                ecstart(ifp->if_unit);
        splx(s);
        if (es->es_oactive == 0)
                ecstart(ifp->if_unit);
        splx(s);

-       return (0);
+gotlocal:
+       if (mcopy)                              /* Kludge, but it works! */
+               return(looutput(&loif, mcopy, dst));
+       else
+               return (0);

 qfull:
        m0 = m;
        splx(s);
 qfull:
        m0 = m;
        splx(s);