From 3f0a1b58ae1fb72dee348564d03f42cca2338ab8 Mon Sep 17 00:00:00 2001 From: david decotigny Date: Fri, 24 Aug 2012 17:22:53 +0000 Subject: [PATCH] forcedeth: prevent TX timeouts after reboot This complements patch "net-forcedeth: fix TX timeout caused by TX pause on down link" which ensures that a lock-up sequence is not sent to the NIC. Present patch ensures that if a NIC is already locked-up, the driver will recover from it when initializing the device. It does the equivalent of the following recovery sequence: - write NVREG_TX_PAUSEFRAME_ENABLE_V1 to eth1's register NvRegTxPauseFrame - write NVREG_XMITCTL_START to eth1's register NvRegTransmitterControl - write 0 to eth1's register NvRegTransmitterControl (this is at the heart of the "unbricking" sequence mentioned in patch "net-forcedeth: fix TX timeout caused by TX pause on down link") Tested: - hardware is MCP55 device id 10de:0373 (rev a3), dual-port - reboot a kernel without any of patches mentioned - freeze the NIC (details on description for commit "net-forcedeth: fix TX timeout caused by TX pause on down link") - wait 5mn until ping hangs & TX timeout in dmesg - reboot on kernel with present patch - host is immediatly operational, no TX timeout Signed-off-by: David Decotigny Signed-off-by: David S. Miller --- drivers/net/ethernet/nvidia/forcedeth.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/nvidia/forcedeth.c b/drivers/net/ethernet/nvidia/forcedeth.c index 8b82457..876bece 100644 --- a/drivers/net/ethernet/nvidia/forcedeth.c +++ b/drivers/net/ethernet/nvidia/forcedeth.c @@ -5905,11 +5905,19 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i goto out_error; } + netif_carrier_off(dev); + + /* Some NICs freeze when TX pause is enabled while NIC is + * down, and this stays across warm reboots. The sequence + * below should be enough to recover from that state. + */ + nv_update_pause(dev, 0); + nv_start_tx(dev); + nv_stop_tx(dev); + if (id->driver_data & DEV_HAS_VLAN) nv_vlan_mode(dev, dev->features); - netif_carrier_off(dev); - dev_info(&pci_dev->dev, "ifname %s, PHY OUI 0x%x @ %d, addr %pM\n", dev->name, np->phy_oui, np->phyaddr, dev->dev_addr); -- 2.7.4