[src/trunk]: src/sys/arch/arm26/ioc Re-organize eca_gotframe to make the logi...

[bjh21 <bjh21%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/aa78327ddb4c
branches:  trunk
changeset: 515339:aa78327ddb4c
user:      bjh21 <bjh21%NetBSD.org@localhost>
date:      Sat Sep 22 14:42:51 2001 +0000

description:
Re-organize eca_gotframe to make the logic a little clearer (to me).

diffstat:

 sys/arch/arm26/ioc/if_eca.c |  53 ++++++++++++++++++++++++++------------------
 1 files changed, 31 insertions(+), 22 deletions(-)

diffs (108 lines):

diff -r 41e729235e4a -r aa78327ddb4c sys/arch/arm26/ioc/if_eca.c
--- a/sys/arch/arm26/ioc/if_eca.c       Sat Sep 22 13:05:36 2001 +0000
+++ b/sys/arch/arm26/ioc/if_eca.c       Sat Sep 22 14:42:51 2001 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_eca.c,v 1.5 2001/09/20 21:54:11 bjh21 Exp $ */
+/*     $NetBSD: if_eca.c,v 1.6 2001/09/22 14:42:51 bjh21 Exp $ */
 
 /*-
  * Copyright (c) 2001 Ben Harris
@@ -29,7 +29,7 @@
 
 #include <sys/param.h>
 
-__KERNEL_RCSID(0, "$NetBSD: if_eca.c,v 1.5 2001/09/20 21:54:11 bjh21 Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_eca.c,v 1.6 2001/09/22 14:42:51 bjh21 Exp $");
 
 #include <sys/device.h>
 #include <sys/malloc.h>
@@ -405,7 +405,9 @@
 }
 
 /*
- * This is a soft interrupt handler, and hence can get away with anything.
+ * eca_gotframe() is called if there's something interesting on
+ * reception.  The receiver is turned off now -- it's up to us to
+ * start it again.
  */
 static void
 eca_gotframe(void *arg)
@@ -420,17 +422,10 @@
 
        reply = NULL;
        sr2 = sc->sc_sr2;
-       /* OVRN and FV can be set together. */
-       if (__predict_false(sr2 & MC6854_SR2_OVRN)) {
-               log(LOG_ERR, "%s: Rx overrun\n", sc->sc_dev.dv_xname);
-               ifp->if_ierrors++;
 
-               /* Discard the rest of the frame. */
-               if (!sc->sc_transmitting)
-                       bus_space_write_1(iot, ioh, MC6854_CR1,
-                           sc->sc_cr1 | MC6854_CR1_DISCONTINUE);
-       } else if (__predict_true(sr2 & MC6854_SR2_FV)) {
-               /* Frame Valid. */
+       /* 1: Is there a valid frame waiting? */
+       if ((sr2 & MC6854_SR2_FV) && !(sr2 & MC6854_SR2_OVRN) &&
+           sc->sc_fiqstate.efs_rx_curmbuf != NULL) {
                fiq_getregs(&fr);
                m = sc->sc_rcvmbuf;
                mtail = sc->sc_fiqstate.efs_rx_curmbuf;
@@ -452,6 +447,17 @@
                        reply = eco_inputframe(ifp, m);
                } else
                        ifp->if_iqdrops++;
+       }
+
+       /* 2: Are there any errors waiting? */
+       if (sr2 & MC6854_SR2_OVRN) {
+               log(LOG_ERR, "%s: Rx overrun\n", sc->sc_dev.dv_xname);
+               ifp->if_ierrors++;
+
+               /* Discard the rest of the frame. */
+               if (!sc->sc_transmitting)
+                       bus_space_write_1(iot, ioh, MC6854_CR1,
+                           sc->sc_cr1 | MC6854_CR1_DISCONTINUE);
        } else if (sr2 & MC6854_SR2_RXABT) {
                log(LOG_NOTICE, "%s: Rx abort\n", sc->sc_dev.dv_xname);
                ifp->if_ierrors++;
@@ -464,10 +470,6 @@
                log(LOG_ERR, "%s: No clock\n", sc->sc_dev.dv_xname);
                ifp->if_ierrors++;
        }
-
-       if (sr2 & MC6854_SR2_RX_IDLE)
-               eco_inputidle(ifp);
-
        if (sc->sc_fiqstate.efs_rx_curmbuf == NULL) {
                log(LOG_NOTICE, "%s: Oversized frame\n", sc->sc_dev.dv_xname);
                ifp->if_ierrors++;
@@ -477,16 +479,23 @@
                            sc->sc_cr1 | MC6854_CR1_DISCONTINUE);
        }
 
+
        bus_space_write_1(iot, ioh, MC6854_CR2,
            sc->sc_cr2 | MC6854_CR2_CLR_RX_ST);
 
-       if (reply)
+       if (reply) {
+               KASSERT(sc->sc_fiqstate.efs_rx_flags & ERXF_FLAGFILL);
                eca_txframe(ifp, reply);
-       else if (!sc->sc_transmitting) {
-               /* Make sure we're not flag-filling. */
-               bus_space_write_1(iot, ioh, MC6854_CR2,
-                   sc->sc_cr2);
+       } else {
+               KASSERT(!sc->sc_transmitting);
+               if (sc->sc_fiqstate.efs_rx_flags & ERXF_FLAGFILL)
+                       /* Stop flag-filling: we have nothing to send. */
+                       bus_space_write_1(iot, ioh, MC6854_CR2,
+                           sc->sc_cr2);
                /* Set the ADLC up to receive the next frame. */
                eca_init_rx(sc);
+               /* 3: Is the network idle now? */
+               if (sr2 & MC6854_SR2_RX_IDLE)
+                       eco_inputidle(ifp);
        }
 }