Commit 633e7533 authored by Rob Herring's avatar Rob Herring Committed by David S. Miller
Browse files

fec: fix uninitialized rx buffer usage 



The fec driver was enabling receive buffer descriptor without allocating
the buffers. Make sure the buffer descriptors are initialized to not
start receiving packets.

Open also calls fec_restart after the rx buffers are allocated. With the code
in fec_restart, it zeroes out the buffer descriptors that have just been
setup.

Signed-off-by: default avatarRob Herring <r.herring@freescale.com>
Signed-off-by: default avatarAmit Kucheria <amit.kucheria@canonical.com>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Acked-by: default avatarGreg Ungerer <gerg@uclinux.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 67de7924

drivers/net/fec.c

+29 −28
Original line number Diff line number Diff line
@@ -1658,6 +1658,7 @@ static int fec_enet_init(struct net_device *dev, int index) 
{

	struct fec_enet_private *fep = netdev_priv(dev);

	struct bufdesc *cbd_base;

	struct bufdesc *bdp;

	int i;



	/* Allocate memory for buffer descriptors. */
@@ -1710,6 +1711,34 @@ static int fec_enet_init(struct net_device *dev, int index) 
	/* Set MII speed to 2.5 MHz */

	fep->phy_speed = ((((clk_get_rate(fep->clk) / 2 + 4999999)

					/ 2500000) / 2) & 0x3F) << 1;



	/* Initialize the receive buffer descriptors. */

	bdp = fep->rx_bd_base;

	for (i = 0; i < RX_RING_SIZE; i++) {



		/* Initialize the BD for every fragment in the page. */

		bdp->cbd_sc = 0;

		bdp++;

	}



	/* Set the last buffer to wrap */

	bdp--;

	bdp->cbd_sc |= BD_SC_WRAP;



	/* ...and the same for transmit */

	bdp = fep->tx_bd_base;

	for (i = 0; i < TX_RING_SIZE; i++) {



		/* Initialize the BD for every fragment in the page. */

		bdp->cbd_sc = 0;

		bdp->cbd_bufaddr = 0;

		bdp++;

	}



	/* Set the last buffer to wrap */

	bdp--;

	bdp->cbd_sc |= BD_SC_WRAP;



	fec_restart(dev, 0);



	/* Queue up command to detect the PHY and initialize the
@@ -1730,7 +1759,6 @@ static void 
fec_restart(struct net_device *dev, int duplex)

{

	struct fec_enet_private *fep = netdev_priv(dev);

	struct bufdesc *bdp;

	int i;



	/* Whack a reset.  We should wait for this. */
@@ -1768,33 +1796,6 @@ fec_restart(struct net_device *dev, int duplex) 
		}

	}



	/* Initialize the receive buffer descriptors. */

	bdp = fep->rx_bd_base;

	for (i = 0; i < RX_RING_SIZE; i++) {



		/* Initialize the BD for every fragment in the page. */

		bdp->cbd_sc = BD_ENET_RX_EMPTY;

		bdp++;

	}



	/* Set the last buffer to wrap */

	bdp--;

	bdp->cbd_sc |= BD_SC_WRAP;



	/* ...and the same for transmit */

	bdp = fep->tx_bd_base;

	for (i = 0; i < TX_RING_SIZE; i++) {



		/* Initialize the BD for every fragment in the page. */

		bdp->cbd_sc = 0;

		bdp->cbd_bufaddr = 0;

		bdp++;

	}



	/* Set the last buffer to wrap */

	bdp--;

	bdp->cbd_sc |= BD_SC_WRAP;



	/* Enable MII mode */

	if (duplex) {

		/* MII enable / FD enable */