svn commit: r325985 - head/sys/arm/allwinner

[Emmanuel Vadot]

Author: manu
Date: Sat Nov 18 21:12:06 2017
New Revision: 325985
URL: https://svnweb.freebsd.org/changeset/base/325985

Log:
  if_awg: drain tx buffers and clear rx buffers when stopping
  
  Stale packets should not be transmitted when the interface comes up after being down.
  Count the successfully transmitted ones for statistics and drop the rest.
  
  Submitted by:	Guy Yur <guyyur at gmail.com>
  Differential Revision:	https://reviews.freebsd.org/D12539

Modified:
  head/sys/arm/allwinner/if_awg.c

Modified: head/sys/arm/allwinner/if_awg.c
==============================================================================
--- head/sys/arm/allwinner/if_awg.c	Sat Nov 18 21:08:18 2017	(r325984)
+++ head/sys/arm/allwinner/if_awg.c	Sat Nov 18 21:12:06 2017	(r325985)
@@ -215,6 +215,8 @@ static struct resource_spec awg_spec[] = {
 	{ -1, 0 }
 };
 
+static void awg_txeof(struct awg_softc *sc);
+
 static int
 awg_miibus_readreg(device_t dev, int phy, int reg)
 {
@@ -809,6 +811,7 @@ awg_stop(struct awg_softc *sc)
 {
 	if_t ifp;
 	uint32_t val;
+	int i;
 
 	AWG_ASSERT_LOCKED(sc);
 
@@ -842,6 +845,39 @@ awg_stop(struct awg_softc *sc)
 	WR4(sc, EMAC_RX_CTL_1, val & ~RX_DMA_EN);
 
 	sc->link = 0;
+
+	/* Finish handling transmitted buffers */
+	awg_txeof(sc);
+
+	/* Release any untransmitted buffers. */
+	for (i = sc->tx.next; sc->tx.queued > 0; i = TX_NEXT(i)) {
+		val = le32toh(sc->tx.desc_ring[i].status);
+		if ((val & TX_DESC_CTL) != 0)
+			break;
+		awg_clean_txbuf(sc, i);
+	}
+	sc->tx.next = i;
+	for (; sc->tx.queued > 0; i = TX_NEXT(i)) {
+		sc->tx.desc_ring[i].status = 0;
+		awg_clean_txbuf(sc, i);
+	}
+	sc->tx.cur = sc->tx.next;
+	bus_dmamap_sync(sc->tx.desc_tag, sc->tx.desc_map,
+	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
+
+	/* Setup RX buffers for reuse */
+	bus_dmamap_sync(sc->rx.desc_tag, sc->rx.desc_map,
+	    BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE);
+
+	for (i = sc->rx.cur; ; i = RX_NEXT(i)) {
+		val = le32toh(sc->rx.desc_ring[i].status);
+		if ((val & RX_DESC_CTL) != 0)
+			break;
+		awg_reuse_rxdesc(sc, i);
+	}
+	sc->rx.cur = i;
+	bus_dmamap_sync(sc->rx.desc_tag, sc->rx.desc_map,
+	    BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE);
 
 	if_setdrvflagbits(ifp, 0, IFF_DRV_RUNNING | IFF_DRV_OACTIVE);
 }