Re: mec and resets

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