svn commit: r200873 - head/sys/dev/ste

[Pyun YongHyeon]

Author: yongari
Date: Tue Dec 22 20:57:30 2009
New Revision: 200873
URL: http://svn.freebsd.org/changeset/base/200873

Log:
  Instead of relying on hard resetting of controller to stop
  receiving incoming traffics, try harder to gracefully stop active
  DMA cycles and then stop MACs. This is the way what datasheet
  recommends and seems to work reliably. Resetting controller while
  active DMAs are in progress is bad thing as we can't predict how
  DMAs touche allocated TX/RX buffers. This change ensures controller
  stop state before attempting to release allocated TX/RX buffers.
  Also update MAC statistics which could have been updated during the
  wait time of MAC stop.
  
  While I'm here remove unnecessary controller resets in various
  location. ste(4) no longer relies on hard controller reset to stop
  controller and resetting controller also clears all configured
  settings which makes it hard to implement WOL in near future.
  Now resetting a controller is performed in ste_init_locked().

Modified:
  head/sys/dev/ste/if_ste.c

Modified: head/sys/dev/ste/if_ste.c
==============================================================================
--- head/sys/dev/ste/if_ste.c	Tue Dec 22 20:56:33 2009	(r200872)
+++ head/sys/dev/ste/if_ste.c	Tue Dec 22 20:57:30 2009	(r200873)
@@ -651,10 +651,8 @@ ste_poll_locked(struct ifnet *ifp, enum 
 		if (status & STE_ISR_STATS_OFLOW)
 			ste_stats_update(sc);
 
-		if (status & STE_ISR_HOSTERR) {
-			ste_reset(sc);
+		if (status & STE_ISR_HOSTERR)
 			ste_init_locked(sc);
-		}
 	}
 	return (rx_npkts);
 }
@@ -702,10 +700,8 @@ ste_intr(void *xsc)
 		if (status & STE_ISR_STATS_OFLOW)
 			ste_stats_update(sc);
 
-		if (status & STE_ISR_HOSTERR) {
-			ste_reset(sc);
+		if (status & STE_ISR_HOSTERR)
 			ste_init_locked(sc);
-		}
 	}
 
 	/* Re-enable interrupts */
@@ -816,7 +812,6 @@ ste_txeoc(struct ste_softc *sc)
 			device_printf(sc->ste_dev,
 			    "transmission error: %x\n", txstat);
 
-			ste_reset(sc);
 			ste_init_locked(sc);
 
 			if (txstat & STE_TXSTATUS_UNDERRUN &&
@@ -1528,6 +1523,8 @@ ste_init_locked(struct ste_softc *sc)
 	ifp = sc->ste_ifp;
 
 	ste_stop(sc);
+	/* Reset the chip to a known state. */
+	ste_reset(sc);
 
 	/* Init our MAC address */
 	for (i = 0; i < ETHER_ADDR_LEN; i += 2) {
@@ -1633,6 +1630,7 @@ ste_stop(struct ste_softc *sc)
 	struct ifnet *ifp;
 	struct ste_chain_onefrag *cur_rx;
 	struct ste_chain *cur_tx;
+	uint32_t val;
 	int i;
 
 	STE_LOCK_ASSERT(sc);
@@ -1643,19 +1641,33 @@ ste_stop(struct ste_softc *sc)
 	ifp->if_drv_flags &= ~(IFF_DRV_RUNNING|IFF_DRV_OACTIVE);
 
 	CSR_WRITE_2(sc, STE_IMR, 0);
-	STE_SETBIT2(sc, STE_MACCTL1, STE_MACCTL1_TX_DISABLE);
-	STE_SETBIT2(sc, STE_MACCTL1, STE_MACCTL1_RX_DISABLE);
-	STE_SETBIT2(sc, STE_MACCTL1, STE_MACCTL1_STATS_DISABLE);
-	STE_SETBIT2(sc, STE_DMACTL, STE_DMACTL_TXDMA_STALL);
-	STE_SETBIT2(sc, STE_DMACTL, STE_DMACTL_RXDMA_STALL);
+	/* Stop pending DMA. */
+	val = CSR_READ_4(sc, STE_DMACTL);
+	val |= STE_DMACTL_TXDMA_STALL | STE_DMACTL_RXDMA_STALL;
+	CSR_WRITE_4(sc, STE_DMACTL, val);
 	ste_wait(sc);
-	/*
-	 * Try really hard to stop the RX engine or under heavy RX
-	 * data chip will write into de-allocated memory.
-	 */
-	ste_reset(sc);
-
-	sc->ste_flags &= ~STE_FLAG_LINK;
+	/* Disable auto-polling. */
+	CSR_WRITE_1(sc, STE_RX_DMAPOLL_PERIOD, 0);
+	CSR_WRITE_1(sc, STE_TX_DMAPOLL_PERIOD, 0);
+	/* Nullify DMA address to stop any further DMA. */
+	CSR_WRITE_4(sc, STE_RX_DMALIST_PTR, 0);
+	CSR_WRITE_4(sc, STE_TX_DMALIST_PTR, 0);
+	/* Stop TX/RX MAC. */
+	val = CSR_READ_2(sc, STE_MACCTL1);
+	val |= STE_MACCTL1_TX_DISABLE | STE_MACCTL1_RX_DISABLE |
+	    STE_MACCTL1_STATS_DISABLE;
+	CSR_WRITE_2(sc, STE_MACCTL1, val);
+	for (i = 0; i < STE_TIMEOUT; i++) {
+		DELAY(10);
+		if ((CSR_READ_2(sc, STE_MACCTL1) & (STE_MACCTL1_TX_DISABLE |
+		    STE_MACCTL1_RX_DISABLE | STE_MACCTL1_STATS_DISABLE)) == 0)
+			break;
+	}
+	if (i == STE_TIMEOUT)
+		device_printf(sc->ste_dev, "Stopping MAC timed out\n");
+	/* Acknowledge any pending interrupts. */
+	CSR_READ_2(sc, STE_ISR_ACK);
+	ste_stats_update(sc);
 
 	for (i = 0; i < STE_RX_LIST_CNT; i++) {
 		cur_rx = &sc->ste_cdata.ste_rx_chain[i];
@@ -1947,7 +1959,6 @@ ste_watchdog(struct ste_softc *sc)
 	ste_txeoc(sc);
 	ste_txeof(sc);
 	ste_rxeof(sc, -1);
-	ste_reset(sc);
 	ste_init_locked(sc);
 
 	if (!IFQ_DRV_IS_EMPTY(&ifp->if_snd))