net: mvpp2: ensure the port is forced down while changing modes

Ensure that the port is forced down while reconfiguring, controlling
this via mac_prepare() and mac_finish() so that it is down while we
are configuring our (future) PCS.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
index 7c0b020..1f5f841 100644 (file)
--- a/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
+++ b/drivers/net/ethernet/marvell/mvpp2/mvpp2_main.c
@@ -5622,9 +5622,7 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
        } else if (state->interface == PHY_INTERFACE_MODE_SGMII) {
                /* SGMII in-band mode receives the speed and duplex from
                 * the PHY. Flow control information is not received. */
-               an &= ~(MVPP2_GMAC_FORCE_LINK_DOWN |
-                       MVPP2_GMAC_FORCE_LINK_PASS |
-                       MVPP2_GMAC_CONFIG_MII_SPEED |
+               an &= ~(MVPP2_GMAC_CONFIG_MII_SPEED |
                        MVPP2_GMAC_CONFIG_GMII_SPEED |
                        MVPP2_GMAC_CONFIG_FULL_DUPLEX);
                an |= MVPP2_GMAC_IN_BAND_AUTONEG |
@@ -5637,9 +5635,7 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
                 * speed and full duplex here.
                 */
                ctrl0 |= MVPP2_GMAC_PORT_TYPE_MASK;
-               an &= ~(MVPP2_GMAC_FORCE_LINK_DOWN |
-                       MVPP2_GMAC_FORCE_LINK_PASS |
-                       MVPP2_GMAC_CONFIG_MII_SPEED |
+               an &= ~(MVPP2_GMAC_CONFIG_MII_SPEED |
                        MVPP2_GMAC_CONFIG_GMII_SPEED |
                        MVPP2_GMAC_CONFIG_FULL_DUPLEX);
                an |= MVPP2_GMAC_IN_BAND_AUTONEG |
@@ -5663,11 +5659,6 @@ static void mvpp2_gmac_config(struct mvpp2_port *port, unsigned int mode,
        if ((old_ctrl0 ^ ctrl0) & MVPP2_GMAC_PORT_TYPE_MASK ||
            (old_ctrl2 ^ ctrl2) & MVPP2_GMAC_INBAND_AN_MASK ||
            (old_an ^ an) & MVPP2_GMAC_AN_PORT_DOWN_MASK) {
-               /* Force link down */
-               old_an &= ~MVPP2_GMAC_FORCE_LINK_PASS;
-               old_an |= MVPP2_GMAC_FORCE_LINK_DOWN;
-               writel(old_an, port->base + MVPP2_GMAC_AUTONEG_CONFIG);
-
                /* Set the GMAC in a reset state - do this in a way that
                 * ensures we clear it below.
                 */
@@ -5702,6 +5693,26 @@ static int mvpp2_mac_prepare(struct phylink_config *config, unsigned int mode,
                return -EINVAL;
        }
 
+       if (port->phy_interface != interface ||
+           phylink_autoneg_inband(mode)) {
+               /* Force the link down when changing the interface or if in
+                * in-band mode to ensure we do not change the configuration
+                * while the hardware is indicating link is up. We force both
+                * XLG and GMAC down to ensure that they're both in a known
+                * state.
+                */
+               mvpp2_modify(port->base + MVPP2_GMAC_AUTONEG_CONFIG,
+                            MVPP2_GMAC_FORCE_LINK_PASS |
+                            MVPP2_GMAC_FORCE_LINK_DOWN,
+                            MVPP2_GMAC_FORCE_LINK_DOWN);
+
+               if (mvpp2_port_supports_xlg(port))
+                       mvpp2_modify(port->base + MVPP22_XLG_CTRL0_REG,
+                                    MVPP22_XLG_CTRL0_FORCE_LINK_PASS |
+                                    MVPP22_XLG_CTRL0_FORCE_LINK_DOWN,
+                                    MVPP22_XLG_CTRL0_FORCE_LINK_DOWN);
+       }
+
        /* Make sure the port is disabled when reconfiguring the mode */
        mvpp2_port_disable(port);
 
@@ -5750,6 +5761,20 @@ static int mvpp2_mac_finish(struct phylink_config *config, unsigned int mode,
 
        mvpp2_port_enable(port);
 
+       /* Allow the link to come up if in in-band mode, otherwise the
+        * link is forced via mac_link_down()/mac_link_up()
+        */
+       if (phylink_autoneg_inband(mode)) {
+               if (mvpp2_is_xlg(interface))
+                       mvpp2_modify(port->base + MVPP22_XLG_CTRL0_REG,
+                                    MVPP22_XLG_CTRL0_FORCE_LINK_PASS |
+                                    MVPP22_XLG_CTRL0_FORCE_LINK_DOWN, 0);
+               else
+                       mvpp2_modify(port->base + MVPP2_GMAC_AUTONEG_CONFIG,
+                                    MVPP2_GMAC_FORCE_LINK_PASS |
+                                    MVPP2_GMAC_FORCE_LINK_DOWN, 0);
+       }
+
        return 0;
 }