[PATCH 5.10 090/103] net: mvpp2: disable force link UP during port init procedure

[Greg Kroah-Hartman]

From: Stefan Chulski <stefanc@xxxxxxxxxxx>

commit 87508224485323ce2d4e7fb929ec80f51adcc238 upstream.

Force link UP can be enabled by bootloader during tftpboot
and breaks NFS support.
Force link UP disabled during port init procedure.

Fixes: f84bf386f395 ("net: mvpp2: initialize the GoP")
Signed-off-by: Stefan Chulski <stefanc@xxxxxxxxxxx>
Acked-by: Marcin Wojtas <mw@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/1608216735-14501-1-git-send-email-stefanc@xxxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c |   14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -5480,7 +5480,7 @@ static int mvpp2_port_init(struct mvpp2_
 	struct mvpp2 *priv = port->priv;
 	struct mvpp2_txq_pcpu *txq_pcpu;
 	unsigned int thread;
-	int queue, err;
+	int queue, err, val;
 
 	/* Checks for hardware constraints */
 	if (port->first_rxq + port->nrxqs >
@@ -5494,6 +5494,18 @@ static int mvpp2_port_init(struct mvpp2_
 	mvpp2_egress_disable(port);
 	mvpp2_port_disable(port);
 
+	if (mvpp2_is_xlg(port->phy_interface)) {
+		val = readl(port->base + MVPP22_XLG_CTRL0_REG);
+		val &= ~MVPP22_XLG_CTRL0_FORCE_LINK_PASS;
+		val |= MVPP22_XLG_CTRL0_FORCE_LINK_DOWN;
+		writel(val, port->base + MVPP22_XLG_CTRL0_REG);
+	} else {
+		val = readl(port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+		val &= ~MVPP2_GMAC_FORCE_LINK_PASS;
+		val |= MVPP2_GMAC_FORCE_LINK_DOWN;
+		writel(val, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
+	}
+
 	port->tx_time_coal = MVPP2_TXDONE_COAL_USEC;
 
 	port->txqs = devm_kcalloc(dev, port->ntxqs, sizeof(*port->txqs),