Re: mec and resets

[Izumi Tsutsui <tsutsui%ceres.dti.ne.jp@localhost>]

I wrote:
> Please try this one.

This is an updated one (mostly taken from OpenBSD):
---

Index: if_mec.c
===================================================================
RCS file: /cvsroot/src/sys/arch/sgimips/mace/if_mec.c,v
retrieving revision 1.20
diff -u -r1.20 if_mec.c
--- if_mec.c    14 May 2008 13:29:28 -0000      1.20
+++ if_mec.c    2 Aug 2008 06:01:32 -0000
@@ -125,6 +125,7 @@
 #define MEC_NTXDESC            64
 #define MEC_NTXDESC_MASK       (MEC_NTXDESC - 1)
 #define MEC_NEXTTX(x)          (((x) + 1) & MEC_NTXDESC_MASK)
+#define MEC_NTXDESC_RSVD       4
 
 /*
  * software state for TX
@@ -341,8 +342,8 @@
 static void    mec_setfilter(struct mec_softc *);
 static int     mec_intr(void *arg);
 static void    mec_stop(struct ifnet *, int);
-static void    mec_rxintr(struct mec_softc *);
-static void    mec_txintr(struct mec_softc *);
+static void    mec_rxintr(struct mec_softc *, uint32_t);
+static void    mec_txintr(struct mec_softc *, uint32_t);
 static void    mec_shutdown(void *);
 
 CFATTACH_DECL_NEW(mec, sizeof(struct mec_softc),
@@ -1223,7 +1224,7 @@
        bus_space_tag_t st = sc->sc_st;
        bus_space_handle_t sh = sc->sc_sh;
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;
-       uint32_t statreg, statack, dmac;
+       uint32_t statreg, statack, rxptr, txptr;
        int handled, sent;
 
        DPRINTF(MEC_DEBUG_INTR, ("mec_intr: called\n"));
@@ -1246,10 +1247,12 @@
                if (statack &
                    (MEC_INT_RX_THRESHOLD |
                     MEC_INT_RX_FIFO_UNDERFLOW)) {
-                       mec_rxintr(sc);
+                       rxptr = (statreg & MEC_INT_RX_MCL_FIFO_ALIAS)
+                           >> MEC_INT_RX_MCL_FIFO_SHIFT;
+                       txptr &= MEC_NRXDESC_MASK;
+                       mec_rxintr(sc, rxptr);
                }
 
-               dmac = bus_space_read_8(st, sh, MEC_DMA_CONTROL);
                DPRINTF(MEC_DEBUG_INTR,
                    ("mec_intr: DMA_CONT = 0x%08x\n", dmac));
 
@@ -1257,10 +1260,11 @@
                    (MEC_INT_TX_EMPTY |
                     MEC_INT_TX_PACKET_SENT |
                     MEC_INT_TX_ABORT)) {
-                       mec_txintr(sc);
+                       txptr = (statreg & MEC_INT_TX_RING_BUFFER_ALIAS)
+                           >> MEC_INT_TX_RING_BUFFER_SHIFT;
+                       mec_txintr(sc, txptr);
                        sent = 1;
-                       if ((statack & MEC_INT_TX_EMPTY) != 0 &&
-                           (dmac & MEC_DMA_TX_INT_ENABLE) != 0) {
+                       if ((statack & MEC_INT_TX_EMPTY) != 0) {
                                /*
                                 * disable TX interrupt to stop
                                 * TX empty interrupt
@@ -1282,7 +1286,7 @@
                }
        }
 
-       if (sent) {
+       if (sent && IFQ_IS_EMPTY(&ifp->if_snd)) {
                /* try to get more packets going */
                mec_start(ifp);
        }
@@ -1296,7 +1300,7 @@
 }
 
 static void
-mec_rxintr(struct mec_softc *sc)
+mec_rxintr(struct mec_softc *sc, uint32_t rxptr)
 {
        bus_space_tag_t st = sc->sc_st;
        bus_space_handle_t sh = sc->sc_sh;
@@ -1309,7 +1313,7 @@
 
        DPRINTF(MEC_DEBUG_RXINTR, ("mec_rxintr: called\n"));
 
-       for (i = sc->sc_rxptr;; i = MEC_NEXTRX(i)) {
+       for (i = sc->sc_rxptr; i != rxptr; i = MEC_NEXTRX(i)) {
                rxd = &sc->sc_rxdesc[i];
 
                MEC_RXSTATSYNC(sc, i, BUS_DMASYNC_POSTREAD);
@@ -1417,7 +1421,7 @@
 }
 
 static void
-mec_txintr(struct mec_softc *sc)
+mec_txintr(struct mec_softc *sc, uint32_t txptr)
 {
        struct ifnet *ifp = &sc->sc_ethercom.ec_if;
        struct mec_txdesc *txd;
@@ -1427,11 +1431,9 @@
        int i;
        u_int col;
 
-       ifp->if_flags &= ~IFF_OACTIVE;
-
        DPRINTF(MEC_DEBUG_TXINTR, ("mec_txintr: called\n"));
 
-       for (i = sc->sc_txdirty; sc->sc_txpending != 0;
+       for (i = sc->sc_txdirty; i != txptr && sc->sc_txpending != 0;
            i = MEC_NEXTTX(i), sc->sc_txpending--) {
                txd = &sc->sc_txdesc[i];
 
@@ -1478,6 +1480,8 @@
        /* cancel the watchdog timer if there are no pending TX packets */
        if (sc->sc_txpending == 0)
                ifp->if_timer = 0;
+       if (sc->sc_txpending < MEC_NTXDESC - MEC_NTXDESC_RSVD)
+               ifp->if_flags &= ~IFF_OACTIVE;
 }
 
 static void
Index: if_mecreg.h
===================================================================
RCS file: /cvsroot/src/sys/arch/sgimips/mace/if_mecreg.h,v
retrieving revision 1.3
diff -u -r1.3 if_mecreg.h
--- if_mecreg.h 10 Dec 2005 07:05:10 -0000      1.3
+++ if_mecreg.h 2 Aug 2008 06:01:32 -0000
@@ -74,7 +74,9 @@
 #define  MEC_INT_RX_FIFO_UNDERFLOW     0x0000000000000040
 #define  MEC_INT_RX_DMA_UNDERFLOW      0x0000000000000080
 #define  MEC_INT_RX_MCL_FIFO_ALIAS     0x0000000000001f00
+#define  MEC_INT_RX_MCL_FIFO_SHIFT     8
 #define  MEC_INT_TX_RING_BUFFER_ALIAS  0x0000000001ff0000
+#define  MEC_INT_TX_RING_BUFFER_SHIFT  16
 #define  MEC_INT_RX_SEQUENCE_NUMBER    0x000000003e000000
 #define  MEC_INT_MCAST_HASH_OUTPUT     0x0000000040000000
 

---
Izumi Tsutsui