[PATCH 5.9 010/757] net: fec: Fix PHY init after phy_reset_after_clk_enable()

From: Greg Kroah-Hartman
Date: Tue Oct 27 2020 - 12:00:06 EST


From: Marek Vasut <marex@xxxxxxx>

[ Upstream commit 0da1ccbbefb662915228bc17e1c7d4ad28b3ddab ]

The phy_reset_after_clk_enable() does a PHY reset, which means the PHY
loses its register settings. The fec_enet_mii_probe() starts the PHY
and does the necessary calls to configure the PHY via PHY framework,
and loads the correct register settings into the PHY. Therefore,
fec_enet_mii_probe() should be called only after the PHY has been
reset, not before as it is now.

Fixes: 1b0a83ac04e3 ("net: fec: add phy_reset_after_clk_enable() support")
Reviewed-by: Andrew Lunn <andrew@xxxxxxx>
Tested-by: Richard Leitner <richard.leitner@xxxxxxxxxxx>
Signed-off-by: Marek Vasut <marex@xxxxxxx>
Cc: Christoph Niedermaier <cniedermaier@xxxxxxxxxxxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: NXP Linux Team <linux-imx@xxxxxxx>
Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/freescale/fec_main.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -3005,17 +3005,17 @@ fec_enet_open(struct net_device *ndev)
/* Init MAC prior to mii bus probe */
fec_restart(ndev);

- /* Probe and connect to PHY when open the interface */
- ret = fec_enet_mii_probe(ndev);
- if (ret)
- goto err_enet_mii_probe;
-
/* Call phy_reset_after_clk_enable() again if it failed during
* phy_reset_after_clk_enable() before because the PHY wasn't probed.
*/
if (reset_again)
fec_enet_phy_reset_after_clk_enable(ndev);

+ /* Probe and connect to PHY when open the interface */
+ ret = fec_enet_mii_probe(ndev);
+ if (ret)
+ goto err_enet_mii_probe;
+
if (fep->quirks & FEC_QUIRK_ERR006687)
imx6q_cpuidle_fec_irqs_used();