net: dsa: mv88e6xxx: Clear the PDOWN bit on setup

Some of the vendor-specific bootloaders set up this part
of the initialization for us, so this was never added.
However, since upstream bootloaders don't initialize the
chip specifically, they leave the fiber MII's PDOWN flag
set, which means that the CPU port doesn't connect.

This patch checks whether this flag has been clear prior
by something else, and if not make us clear it.

Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Patrick Uiterwijk <patrick@puiterwijk.org>
Tested-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/dsa/mv88e6xxx.c b/drivers/net/dsa/mv88e6xxx.c
index 86a2029..50454be 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx.c
+++ b/drivers/net/dsa/mv88e6xxx.c
@@ -2296,6 +2296,25 @@ restore_page_0:
        return ret;
 }
 
+static int mv88e6xxx_power_on_serdes(struct dsa_switch *ds)
+{
+       int ret;
+
+       ret = _mv88e6xxx_phy_page_read(ds, REG_FIBER_SERDES, PAGE_FIBER_SERDES,
+                                      MII_BMCR);
+       if (ret < 0)
+               return ret;
+
+       if (ret & BMCR_PDOWN) {
+               ret &= ~BMCR_PDOWN;
+               ret = _mv88e6xxx_phy_page_write(ds, REG_FIBER_SERDES,
+                                               PAGE_FIBER_SERDES, MII_BMCR,
+                                               ret);
+       }
+
+       return ret;
+}
+
 static int mv88e6xxx_setup_port(struct dsa_switch *ds, int port)
 {
        struct mv88e6xxx_priv_state *ps = ds_to_priv(ds);
@@ -2399,6 +2418,23 @@ static int mv88e6xxx_setup_port(struct dsa_switch *ds, int port)
                        goto abort;
        }
 
+       /* If this port is connected to a SerDes, make sure the SerDes is not
+        * powered down.
+        */
+       if (mv88e6xxx_6352_family(ds)) {
+               ret = _mv88e6xxx_reg_read(ds, REG_PORT(port), PORT_STATUS);
+               if (ret < 0)
+                       goto abort;
+               ret &= PORT_STATUS_CMODE_MASK;
+               if ((ret == PORT_STATUS_CMODE_100BASE_X) ||
+                   (ret == PORT_STATUS_CMODE_1000BASE_X) ||
+                   (ret == PORT_STATUS_CMODE_SGMII)) {
+                       ret = mv88e6xxx_power_on_serdes(ds);
+                       if (ret < 0)
+                               goto abort;
+               }
+       }
+
        /* Port Control 2: don't force a good FCS, set the maximum frame size to
         * 10240 bytes, disable 802.1q tags checking, don't discard tagged or
         * untagged frames on this port, do a destination address lookup on all

diff --git a/drivers/net/dsa/mv88e6xxx.h b/drivers/net/dsa/mv88e6xxx.h
index 9a038ab..26a424a 100644 (file)
--- a/drivers/net/dsa/mv88e6xxx.h
+++ b/drivers/net/dsa/mv88e6xxx.h
@@ -28,6 +28,10 @@
 #define SMI_CMD_OP_45_READ_DATA_INC    ((3 << 10) | SMI_CMD_BUSY)
 #define SMI_DATA               0x01
 
+/* Fiber/SERDES Registers are located at SMI address F, page 1 */
+#define REG_FIBER_SERDES       0x0f
+#define PAGE_FIBER_SERDES      0x01
+
 #define REG_PORT(p)            (0x10 + (p))
 #define PORT_STATUS            0x00
 #define PORT_STATUS_PAUSE_EN   BIT(15)
@@ -45,6 +49,10 @@
 #define PORT_STATUS_MGMII      BIT(6) /* 6185 */
 #define PORT_STATUS_TX_PAUSED  BIT(5)
 #define PORT_STATUS_FLOW_CTRL  BIT(4)
+#define PORT_STATUS_CMODE_MASK 0x0f
+#define PORT_STATUS_CMODE_100BASE_X    0x8
+#define PORT_STATUS_CMODE_1000BASE_X   0x9
+#define PORT_STATUS_CMODE_SGMII                0xa
 #define PORT_PCS_CTRL          0x01
 #define PORT_PCS_CTRL_RGMII_DELAY_RXCLK        BIT(15)
 #define PORT_PCS_CTRL_RGMII_DELAY_TXCLK        BIT(14)