mlxbf_gige: increase MDIO polling rate to 5us

This patch increases the polling rate used by the
mlxbf_gige driver on the MDIO bus.  The previous
polling rate was every 100us, and the new rate is
every 5us.  With this change the amount of time
spent waiting for the MDIO BUSY signal to de-assert
drops from ~100us to ~27us for each operation.

Signed-off-by: David Thompson <davthompson@nvidia.com>
Signed-off-by: Asmaa Mnebhi <asmaa@nvidia.com>
Link: https://lore.kernel.org/r/20220505162309.20050-1-davthompson@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

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 7905179a95753dee45c7c338b9fb5e295dd715ec..2e6c1b7af0964c230d60f3a12509bedff98d40a4 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c
+++ b/drivers/net/ethernet/mellanox/mlxbf_gige/mlxbf_gige_mdio.c
@@ -105,7 +105,8 @@ static int mlxbf_gige_mdio_read(struct mii_bus *bus, int phy_add, int phy_reg)
        writel(cmd, priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET);
 
        ret = readl_poll_timeout_atomic(priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET,
-                                       val, !(val & MLXBF_GIGE_MDIO_GW_BUSY_MASK), 100, 1000000);
+                                       val, !(val & MLXBF_GIGE_MDIO_GW_BUSY_MASK),
+                                       5, 1000000);
 
        if (ret) {
                writel(0, priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET);
@@ -137,7 +138,8 @@ static int mlxbf_gige_mdio_write(struct mii_bus *bus, int phy_add,
 
        /* If the poll timed out, drop the request */
        ret = readl_poll_timeout_atomic(priv->mdio_io + MLXBF_GIGE_MDIO_GW_OFFSET,
-                                       temp, !(temp & MLXBF_GIGE_MDIO_GW_BUSY_MASK), 100, 1000000);
+                                       temp, !(temp & MLXBF_GIGE_MDIO_GW_BUSY_MASK),
+                                       5, 1000000);
 
        return ret;
 }