net: bcmgenet: power up and down integrated GPHY when unused

Power up the GPHY while we are bringing-up the network interface, and
conversely, upon bring down, power the GPHY down. In order to avoid
creating hardware hazards, make sure that the GPHY gets powered on
during bcmgenet_open() prior to the UniMAC being reset as the UniMAC may
start creating activity towards the GPHY if we reverse the steps.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

3 files changed, 10 insertions, 4 deletions

diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.c b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
index f86837f1656a..c6b15c3cf023 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.c
@@ -869,6 +869,8 @@ static int bcmgenet_power_down(struct bcmgenet_priv *priv,
                         reg |= (EXT_PWR_DOWN_PHY |
                                 EXT_PWR_DOWN_DLL | EXT_PWR_DOWN_BIAS);
                         bcmgenet_ext_writel(priv, reg, EXT_EXT_PWR_MGMT);
+
+                        bcmgenet_phy_power_set(priv->dev, false);
                 }
                 break;
         default:
@@ -2465,9 +2467,6 @@ static void bcmgenet_netif_start(struct net_device *dev)
 
         umac_enable_set(priv, CMD_TX_EN | CMD_RX_EN, true);
 
-        if (phy_is_internal(priv->phydev))
-                bcmgenet_power_up(priv, GENET_POWER_PASSIVE);
-
         netif_tx_start_all_queues(dev);
 
         phy_start(priv->phydev);
@@ -2486,6 +2485,12 @@ static int bcmgenet_open(struct net_device *dev)
         if (!IS_ERR(priv->clk))
                 clk_prepare_enable(priv->clk);
 
+        /* If this is an internal GPHY, power it back on now, before UniMAC is
+         * brought out of reset as absolutely no UniMAC activity is allowed
+         */
+        if (phy_is_internal(priv->phydev))
+                bcmgenet_power_up(priv, GENET_POWER_PASSIVE);
+
         /* take MAC out of reset */
         bcmgenet_umac_reset(priv);
 
diff --git a/drivers/net/ethernet/broadcom/genet/bcmgenet.h b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
index a27ef777cc81..7a59879d441f 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmgenet.h
+++ b/drivers/net/ethernet/broadcom/genet/bcmgenet.h
@@ -664,6 +664,7 @@ int bcmgenet_mii_init(struct net_device *dev);
 int bcmgenet_mii_config(struct net_device *dev, bool init);
 void bcmgenet_mii_exit(struct net_device *dev);
 void bcmgenet_mii_reset(struct net_device *dev);
+void bcmgenet_phy_power_set(struct net_device *dev, bool enable);
 void bcmgenet_mii_setup(struct net_device *dev);
 
 /* Wake-on-LAN routines */
diff --git a/drivers/net/ethernet/broadcom/genet/bcmmii.c b/drivers/net/ethernet/broadcom/genet/bcmmii.c
index 3320219003fb..6d3b66a103cc 100644
--- a/drivers/net/ethernet/broadcom/genet/bcmmii.c
+++ b/drivers/net/ethernet/broadcom/genet/bcmmii.c
@@ -168,7 +168,7 @@ void bcmgenet_mii_reset(struct net_device *dev)
         }
 }
 
-static void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
+void bcmgenet_phy_power_set(struct net_device *dev, bool enable)
 {
         struct bcmgenet_priv *priv = netdev_priv(dev);
         u32 reg = 0;