6 files changed, 87 insertions, 15 deletions

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index 5f93e6add563..e911e4990b20 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -239,14 +239,10 @@ static int at803x_resume(struct phy_device *phydev)
 {
         int value;
 
-        mutex_lock(&phydev->lock);
-
         value = phy_read(phydev, MII_BMCR);
         value &= ~(BMCR_PDOWN | BMCR_ISOLATE);
         phy_write(phydev, MII_BMCR, value);
 
-        mutex_unlock(&phydev->lock);
-
         return 0;
 }
 
diff --git a/drivers/net/phy/marvell.c b/drivers/net/phy/marvell.c
index 4d02b27df044..b5a8f750e433 100644
--- a/drivers/net/phy/marvell.c
+++ b/drivers/net/phy/marvell.c
@@ -637,6 +637,10 @@ static int m88e1510_config_aneg(struct phy_device *phydev)
         if (err < 0)
                 goto error;
 
+        /* Do not touch the fiber page if we're in copper->sgmii mode */
+        if (phydev->interface == PHY_INTERFACE_MODE_SGMII)
+                return 0;
+
         /* Then the fiber link */
         err = marvell_set_page(phydev, MII_MARVELL_FIBER_PAGE);
         if (err < 0)
diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c
index 2df7b62c1a36..54d00a1d2bef 100644
--- a/drivers/net/phy/mdio_bus.c
+++ b/drivers/net/phy/mdio_bus.c
@@ -270,6 +270,7 @@ static void of_mdiobus_link_mdiodev(struct mii_bus *bus,
 
                 if (addr == mdiodev->addr) {
                         dev->of_node = child;
+                        dev->fwnode = of_fwnode_handle(child);
                         return;
                 }
         }
diff --git a/drivers/net/phy/meson-gxl.c b/drivers/net/phy/meson-gxl.c
index 1ea69b7585d9..842eb871a6e3 100644
--- a/drivers/net/phy/meson-gxl.c
+++ b/drivers/net/phy/meson-gxl.c
@@ -22,6 +22,7 @@
 #include <linux/ethtool.h>
 #include <linux/phy.h>
 #include <linux/netdevice.h>
+#include <linux/bitfield.h>
 
 static int meson_gxl_config_init(struct phy_device *phydev)
 {
@@ -50,6 +51,77 @@ static int meson_gxl_config_init(struct phy_device *phydev)
         return 0;
 }
 
+/* This function is provided to cope with the possible failures of this phy
+ * during aneg process. When aneg fails, the PHY reports that aneg is done
+ * but the value found in MII_LPA is wrong:
+ *  - Early failures: MII_LPA is just 0x0001. if MII_EXPANSION reports that
+ *    the link partner (LP) supports aneg but the LP never acked our base
+ *    code word, it is likely that we never sent it to begin with.
+ *  - Late failures: MII_LPA is filled with a value which seems to make sense
+ *    but it actually is not what the LP is advertising. It seems that we
+ *    can detect this using a magic bit in the WOL bank (reg 12 - bit 12).
+ *    If this particular bit is not set when aneg is reported being done,
+ *    it means MII_LPA is likely to be wrong.
+ *
+ * In both case, forcing a restart of the aneg process solve the problem.
+ * When this failure happens, the first retry is usually successful but,
+ * in some cases, it may take up to 6 retries to get a decent result
+ */
+static int meson_gxl_read_status(struct phy_device *phydev)
+{
+        int ret, wol, lpa, exp;
+
+        if (phydev->autoneg == AUTONEG_ENABLE) {
+                ret = genphy_aneg_done(phydev);
+                if (ret < 0)
+                        return ret;
+                else if (!ret)
+                        goto read_status_continue;
+
+                /* Need to access WOL bank, make sure the access is open */
+                ret = phy_write(phydev, 0x14, 0x0000);
+                if (ret)
+                        return ret;
+                ret = phy_write(phydev, 0x14, 0x0400);
+                if (ret)
+                        return ret;
+                ret = phy_write(phydev, 0x14, 0x0000);
+                if (ret)
+                        return ret;
+                ret = phy_write(phydev, 0x14, 0x0400);
+                if (ret)
+                        return ret;
+
+                /* Request LPI_STATUS WOL register */
+                ret = phy_write(phydev, 0x14, 0x8D80);
+                if (ret)
+                        return ret;
+
+                /* Read LPI_STATUS value */
+                wol = phy_read(phydev, 0x15);
+                if (wol < 0)
+                        return wol;
+
+                lpa = phy_read(phydev, MII_LPA);
+                if (lpa < 0)
+                        return lpa;
+
+                exp = phy_read(phydev, MII_EXPANSION);
+                if (exp < 0)
+                        return exp;
+
+                if (!(wol & BIT(12)) ||
+                    ((exp & EXPANSION_NWAY) && !(lpa & LPA_LPACK))) {
+                        /* Looks like aneg failed after all */
+                        phydev_dbg(phydev, "LPA corruption - aneg restart\n");
+                        return genphy_restart_aneg(phydev);
+                }
+        }
+
+read_status_continue:
+        return genphy_read_status(phydev);
+}
+
 static struct phy_driver meson_gxl_phy[] = {
         {
                 .phy_id         = 0x01814400,
@@ -60,7 +132,7 @@ static struct phy_driver meson_gxl_phy[] = {
                 .config_init    = meson_gxl_config_init,
                 .config_aneg    = genphy_config_aneg,
                 .aneg_done      = genphy_aneg_done,
-                .read_status    = genphy_read_status,
+                .read_status    = meson_gxl_read_status,
                 .suspend        = genphy_suspend,
                 .resume         = genphy_resume,
         },
diff --git a/drivers/net/phy/phy.c b/drivers/net/phy/phy.c
index 2b1e67bc1e73..ed10d1fc8f59 100644
--- a/drivers/net/phy/phy.c
+++ b/drivers/net/phy/phy.c
@@ -828,7 +828,6 @@ EXPORT_SYMBOL(phy_stop);
  */
 void phy_start(struct phy_device *phydev)
 {
-        bool do_resume = false;
         int err = 0;
 
         mutex_lock(&phydev->lock);
@@ -841,6 +840,9 @@ void phy_start(struct phy_device *phydev)
                 phydev->state = PHY_UP;
                 break;
         case PHY_HALTED:
+                /* if phy was suspended, bring the physical link up again */
+                phy_resume(phydev);
+
                 /* make sure interrupts are re-enabled for the PHY */
                 if (phydev->irq != PHY_POLL) {
                         err = phy_enable_interrupts(phydev);
@@ -849,17 +851,12 @@ void phy_start(struct phy_device *phydev)
                 }
 
                 phydev->state = PHY_RESUMING;
-                do_resume = true;
                 break;
         default:
                 break;
         }
         mutex_unlock(&phydev->lock);
 
-        /* if phy was suspended, bring the physical link up again */
-        if (do_resume)
-                phy_resume(phydev);
-
         phy_trigger_machine(phydev, true);
 }
 EXPORT_SYMBOL(phy_start);
diff --git a/drivers/net/phy/phy_device.c b/drivers/net/phy/phy_device.c
index 67f25ac29025..b15b31ca2618 100644
--- a/drivers/net/phy/phy_device.c
+++ b/drivers/net/phy/phy_device.c
@@ -135,7 +135,9 @@ static int mdio_bus_phy_resume(struct device *dev)
         if (!mdio_bus_phy_may_suspend(phydev))
                 goto no_resume;
 
+        mutex_lock(&phydev->lock);
         ret = phy_resume(phydev);
+        mutex_unlock(&phydev->lock);
         if (ret < 0)
                 return ret;
 
@@ -1026,7 +1028,9 @@ int phy_attach_direct(struct net_device *dev, struct phy_device *phydev,
         if (err)
                 goto error;
 
+        mutex_lock(&phydev->lock);
         phy_resume(phydev);
+        mutex_unlock(&phydev->lock);
         phy_led_triggers_register(phydev);
 
         return err;
@@ -1157,6 +1161,8 @@ int phy_resume(struct phy_device *phydev)
         struct phy_driver *phydrv = to_phy_driver(phydev->mdio.dev.driver);
         int ret = 0;
 
+        WARN_ON(!mutex_is_locked(&phydev->lock));
+
         if (phydev->drv && phydrv->resume)
                 ret = phydrv->resume(phydev);
 
@@ -1639,13 +1645,9 @@ int genphy_resume(struct phy_device *phydev)
 {
         int value;
 
-        mutex_lock(&phydev->lock);
-
         value = phy_read(phydev, MII_BMCR);
         phy_write(phydev, MII_BMCR, value & ~BMCR_PDOWN);
 
-        mutex_unlock(&phydev->lock);
-
         return 0;
 }
 EXPORT_SYMBOL(genphy_resume);