forcedeth bug fix: realtek phy 8211c errata

This patch adds support for the realtek 8211c phy. The driver must
perform a hardware reset of the phy due to an errata where the phy could
not detect the link.
Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/net/forcedeth.c

@@ -333,6 +333,7 @@ enum {
 	NvRegPowerState2 = 0x600,
 #define NVREG_POWERSTATE2_POWERUP_MASK		0x0F11
 #define NVREG_POWERSTATE2_POWERUP_REV_A3	0x0001
+#define NVREG_POWERSTATE2_PHY_RESET		0x0004
 };
 
 /* Big endian: should work, but is untested */
@@ -529,6 +530,7 @@ union ring_type {
 #define PHY_REALTEK_INIT_REG4	0x14
 #define PHY_REALTEK_INIT_REG5	0x18
 #define PHY_REALTEK_INIT_REG6	0x11
+#define PHY_REALTEK_INIT_REG7	0x01
 #define PHY_REALTEK_INIT1	0x0000
 #define PHY_REALTEK_INIT2	0x8e00
 #define PHY_REALTEK_INIT3	0x0001
@@ -537,6 +539,9 @@ union ring_type {
 #define PHY_REALTEK_INIT6	0xf5c7
 #define PHY_REALTEK_INIT7	0x1000
 #define PHY_REALTEK_INIT8	0x0003
+#define PHY_REALTEK_INIT9	0x0008
+#define PHY_REALTEK_INIT10	0x0005
+#define PHY_REALTEK_INIT11	0x0200
 #define PHY_REALTEK_INIT_MSK1	0x0003
 
 #define PHY_GIGABIT	0x0100
@@ -1149,6 +1154,42 @@ static int phy_init(struct net_device *dev)
 				return PHY_ERROR;
 			}
 		}
+		if (np->phy_model == PHY_MODEL_REALTEK_8211 &&
+		    np->phy_rev == PHY_REV_REALTEK_8211C) {
+			u32 powerstate = readl(base + NvRegPowerState2);
+
+			/* need to perform hw phy reset */
+			powerstate |= NVREG_POWERSTATE2_PHY_RESET;
+			writel(powerstate, base + NvRegPowerState2);
+			msleep(25);
+
+			powerstate &= ~NVREG_POWERSTATE2_PHY_RESET;
+			writel(powerstate, base + NvRegPowerState2);
+			msleep(25);
+
+			reg = mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG6, MII_READ);
+			reg |= PHY_REALTEK_INIT9;
+			if (mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG6, reg)) {
+				printk(KERN_INFO "%s: phy init failed.\n", pci_name(np->pci_dev));
+				return PHY_ERROR;
+			}
+			if (mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG1, PHY_REALTEK_INIT10)) {
+				printk(KERN_INFO "%s: phy init failed.\n", pci_name(np->pci_dev));
+				return PHY_ERROR;
+			}
+			reg = mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG7, MII_READ);
+			if (!(reg & PHY_REALTEK_INIT11)) {
+				reg |= PHY_REALTEK_INIT11;
+				if (mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG7, reg)) {
+					printk(KERN_INFO "%s: phy init failed.\n", pci_name(np->pci_dev));
+					return PHY_ERROR;
+				}
+			}
+			if (mii_rw(dev, np->phyaddr, PHY_REALTEK_INIT_REG1, PHY_REALTEK_INIT1)) {
+				printk(KERN_INFO "%s: phy init failed.\n", pci_name(np->pci_dev));
+				return PHY_ERROR;
+			}
+		}
 		if (np->phy_model == PHY_MODEL_REALTEK_8201) {
 			if (np->device_id == PCI_DEVICE_ID_NVIDIA_NVENET_32 ||
 			    np->device_id == PCI_DEVICE_ID_NVIDIA_NVENET_33 ||
@@ -1201,6 +1242,16 @@ static int phy_init(struct net_device *dev)
 	mii_control = mii_rw(dev, np->phyaddr, MII_BMCR, MII_READ);
 	mii_control |= BMCR_ANENABLE;
 
+	if (np->phy_oui == PHY_OUI_REALTEK &&
+	    np->phy_model == PHY_MODEL_REALTEK_8211 &&
+	    np->phy_rev == PHY_REV_REALTEK_8211C) {
+		/* start autoneg since we already performed hw reset above */
+		mii_control |= BMCR_ANRESTART;
+		if (mii_rw(dev, np->phyaddr, MII_BMCR, mii_control)) {
+			printk(KERN_INFO "%s: phy init failed\n", pci_name(np->pci_dev));
+			return PHY_ERROR;
+		}
+	} else {
 		/* reset the phy
 		 * (certain phys need bmcr to be setup with reset)
 		 */
@@ -1208,6 +1259,7 @@ static int phy_init(struct net_device *dev)
 			printk(KERN_INFO "%s: phy reset failed\n", pci_name(np->pci_dev));
 			return PHY_ERROR;
 		}
+	}
 
 	/* phy vendor specific configuration */
 	if ((np->phy_oui == PHY_OUI_CICADA) && (phyinterface & PHY_RGMII) ) {