From 911b237d7d327db5371a762f4d8d8cd9ea763662 Mon Sep 17 00:00:00 2001 From: Benjamin Herrenschmidt Date: Wed, 5 Dec 2007 11:14:27 +1100 Subject: [PATCH] ibm_newemac: Workaround reset timeout when no link With some PHYs, when the link goes away, the EMAC reset fails due to the loss of the RX clock I believe. The old EMAC driver worked around that using some internal chip-specific clock force bits that are different on various 44x implementations. This is an attempt at doing it differently, by avoiding the reset when there is no link, but forcing loopback mode instead. It seems to work on my Taishan 440GX based board so far. Signed-off-by: Benjamin Herrenschmidt Acked-by: Stefan Roese Signed-off-by: Jeff Garzik --- drivers/net/ibm_newemac/core.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) diff --git a/drivers/net/ibm_newemac/core.c b/drivers/net/ibm_newemac/core.c index eb0718b..e0eae09 100644 --- a/drivers/net/ibm_newemac/core.c +++ b/drivers/net/ibm_newemac/core.c @@ -464,26 +464,34 @@ static int emac_configure(struct emac_instance *dev) { struct emac_regs __iomem *p = dev->emacp; struct net_device *ndev = dev->ndev; - int tx_size, rx_size; + int tx_size, rx_size, link = netif_carrier_ok(dev->ndev); u32 r, mr1 = 0; DBG(dev, "configure" NL); - if (emac_reset(dev) < 0) + if (!link) { + out_be32(&p->mr1, in_be32(&p->mr1) + | EMAC_MR1_FDE | EMAC_MR1_ILE); + udelay(100); + } else if (emac_reset(dev) < 0) return -ETIMEDOUT; if (emac_has_feature(dev, EMAC_FTR_HAS_TAH)) tah_reset(dev->tah_dev); - DBG(dev, " duplex = %d, pause = %d, asym_pause = %d\n", - dev->phy.duplex, dev->phy.pause, dev->phy.asym_pause); + DBG(dev, " link = %d duplex = %d, pause = %d, asym_pause = %d\n", + link, dev->phy.duplex, dev->phy.pause, dev->phy.asym_pause); /* Default fifo sizes */ tx_size = dev->tx_fifo_size; rx_size = dev->rx_fifo_size; + /* No link, force loopback */ + if (!link) + mr1 = EMAC_MR1_FDE | EMAC_MR1_ILE; + /* Check for full duplex */ - if (dev->phy.duplex == DUPLEX_FULL) + else if (dev->phy.duplex == DUPLEX_FULL) mr1 |= EMAC_MR1_FDE | EMAC_MR1_MWSW_001; /* Adjust fifo sizes, mr1 and timeouts based on link speed */ @@ -1165,9 +1173,9 @@ static void emac_link_timer(struct work_struct *work) link_poll_interval = PHY_POLL_LINK_ON; } else { if (netif_carrier_ok(dev->ndev)) { - emac_reinitialize(dev); netif_carrier_off(dev->ndev); netif_tx_disable(dev->ndev); + emac_reinitialize(dev); emac_print_link_status(dev); } link_poll_interval = PHY_POLL_LINK_OFF; -- 2.7.4