From: David Thompson Date: Fri, 2 Sep 2022 16:42:47 +0000 (-0400) Subject: mlxbf_gige: clear MDIO gateway lock after read X-Git-Tag: v5.19.12~95 X-Git-Url: http://git.itanic.dy.fi/?p=linux-stable;a=commitdiff_plain;h=36da184d2196f9ebc68bf35f61eea5e2f6a475c4 mlxbf_gige: clear MDIO gateway lock after read [ Upstream commit 182447b12144b7be9b63a273d27c5a11bd54960a ] The MDIO gateway (GW) lock in BlueField-2 GIGE logic is set after read. This patch adds logic to make sure the lock is always cleared at the end of each MDIO transaction. Fixes: f92e1869d74e ("Add Mellanox BlueField Gigabit Ethernet driver") Reviewed-by: Asmaa Mnebhi Signed-off-by: David Thompson Link: https://lore.kernel.org/r/20220902164247.19862-1-davthompson@nvidia.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- diff --git a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c index 85155cd9405c..4aeb927c3715 100644 --- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c +++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c @@ -179,6 +179,9 @@ static int mlxbf_gige_mdio_read(struct mii_bus *bus, int phy_add, int phy_reg) /* Only return ad bits of the gw register */ ret &= MLXBF_GIGE_MDIO_GW_AD_MASK; + /* The MDIO lock is set on read. To release it, clear gw register */ + writel(0, priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET); + return ret; } @@ -203,6 +206,9 @@ static int mlxbf_gige_mdio_write(struct mii_bus *bus, int phy_add, temp, !(temp & MLXBF_GIGE_MDIO_GW_BUSY_MASK), 5, 1000000); + /* The MDIO lock is set on read. To release it, clear gw register */ + writel(0, priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET); + return ret; }