net: bcmgenet: reset 40nm EPHY on energy detect

BugLink: https://bugs.launchpad.net/bugs/1853208
[ Upstream commit 25382b991d252aed961cd434176240f9de6bb15f ]

The EPHY integrated into the 40nm Set-Top Box devices can falsely
detect energy when connected to a disabled peer interface. When the
peer interface is enabled the EPHY will detect and report the link
as active, but on occasion may get into a state where it is not
able to exchange data with the connected GENET MAC. This issue has
not been observed when the link parameters are auto-negotiated;
however, it has been observed with a manually configured link.

It has been empirically determined that issuing a soft reset to the
EPHY when energy is detected prevents it from getting into this bad
state.

Fixes: 1c1008c793fa ("net: bcmgenet: add main driver file")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Kamal Mostafa <kamal@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index fa9980dc6034e6a3423777f7093daec9a45034c8..b646b89fa4bf023272332de182921d4dcc14765f 100644 (file)
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -1963,6 +1963,8 @@ static void bcmgenet_link_intr_enable(struct bcmgenet_priv *priv)
         */
        if (priv->internal_phy) {
                int0_enable |= UMAC_IRQ_LINK_EVENT;
+               if (GENET_IS_V1(priv) || GENET_IS_V2(priv) || GENET_IS_V3(priv))
+                       int0_enable |= UMAC_IRQ_PHY_DET_R;
        } else if (priv->ext_phy) {
                int0_enable |= UMAC_IRQ_LINK_EVENT;
        } else if (priv->phy_interface == PHY_INTERFACE_MODE_MOCA) {
@@ -2526,10 +2528,15 @@ static void bcmgenet_irq_task(struct work_struct *work)
        priv->irq0_stat = 0;
        spin_unlock_irq(&priv->lock);
 
+       if (status & UMAC_IRQ_PHY_DET_R &&
+           priv->dev->phydev->autoneg != AUTONEG_ENABLE)
+               phy_init_hw(priv->dev->phydev);
+
        /* Link UP/DOWN event */
        if (status & UMAC_IRQ_LINK_EVENT)
                phy_mac_interrupt(priv->dev->phydev,
                                  !!(status & UMAC_IRQ_LINK_UP));
+
 }
 
 /* bcmgenet_isr1: handle Rx and Tx priority queues */
@@ -2622,7 +2629,7 @@ static irqreturn_t bcmgenet_isr0(int irq, void *dev_id)
        }
 
        /* all other interested interrupts handled in bottom half */
-       status &= UMAC_IRQ_LINK_EVENT;
+       status &= (UMAC_IRQ_LINK_EVENT | UMAC_IRQ_PHY_DET_R);
        if (status) {
                /* Save irq status for bottom-half processing. */
                spin_lock_irqsave(&priv->lock, flags);