From c677ba8b3c47650358572091ed8a6af50bfca877 Mon Sep 17 00:00:00 2001 From: Florian Fainelli Date: Mon, 11 Aug 2014 14:50:44 -0700 Subject: [PATCH] net: bcmgenet: update UMAC_CMD only when link is detected When we bring the interface down, phy_stop() will schedule the PHY state machine to call our link adjustment callback. By the time we do so, we may have clock gated off the GENET hardware block, and this will cause bus errors to happen in bcmgenet_mii_setup(): Make sure that we only touch the UMAC_CMD register when there is an actual link. This is safe to do for two reasons: - updating the Ethernet MAC registers only make sense when a physical link is present - the PHY library state machine first set phydev->link = 0 before invoking phydev->adjust_link in the PHY_HALTED case Fixes: 240524089d7a ("net: bcmgenet: only update UMAC_CMD if something changed") Signed-off-by: Florian Fainelli Signed-off-by: David S. Miller --- drivers/net/ethernet/broadcom/genet/bcmmii.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c index b56f1bb..c88f7ae 100644 --- a/drivers/net/ethernet/broadcom/genet/bcmmii.c +++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c @@ -129,7 +129,10 @@ static void bcmgenet_mii_setup(struct net_device *dev) cmd_bits |= CMD_RX_PAUSE_IGNORE | CMD_TX_PAUSE_IGNORE; } - if (status_changed) { + if (!status_changed) + return; + + if (phydev->link) { reg = bcmgenet_umac_readl(priv, UMAC_CMD); reg &= ~((CMD_SPEED_MASK << CMD_SPEED_SHIFT) | CMD_HD_EN | @@ -137,8 +140,9 @@ static void bcmgenet_mii_setup(struct net_device *dev) reg |= cmd_bits; bcmgenet_umac_writel(priv, reg, UMAC_CMD); - phy_print_status(phydev); } + + phy_print_status(phydev); } void bcmgenet_mii_reset(struct net_device *dev) -- 2.7.4