forcedeth: tx collision fix

This patch supports a new fix in hardware regarding tx collisions. In
the cases where we are in autoneg mode and the link partner is in forced
mode, we need to setup the tx deferral register differently in order to
reduce collisions on the wire.

Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/forcedeth.c

@@ -181,6 +181,7 @@
 #define DEV_HAS_TEST_EXTENDED   0x1000  /* device supports extended diagnostic test */
 #define DEV_HAS_MGMT_UNIT       0x2000  /* device supports management unit */
 #define DEV_HAS_CORRECT_MACADDR 0x4000  /* device supports correct mac address order */
+#define DEV_HAS_COLLISION_FIX   0x8000  /* device supports tx collision fix */
 
 enum {
 	NvRegIrqStatus = 0x000,
@@ -266,9 +267,12 @@ enum {
 #define NVREG_RNDSEED_FORCE3	0x7400
 
 	NvRegTxDeferral = 0xA0,
-#define NVREG_TX_DEFERRAL_DEFAULT	0x15050f
-#define NVREG_TX_DEFERRAL_RGMII_10_100	0x16070f
-#define NVREG_TX_DEFERRAL_RGMII_1000	0x14050f
+#define NVREG_TX_DEFERRAL_DEFAULT		0x15050f
+#define NVREG_TX_DEFERRAL_RGMII_10_100		0x16070f
+#define NVREG_TX_DEFERRAL_RGMII_1000		0x14050f
+#define NVREG_TX_DEFERRAL_RGMII_STRETCH_10	0x16190f
+#define NVREG_TX_DEFERRAL_RGMII_STRETCH_100	0x16300f
+#define NVREG_TX_DEFERRAL_MII_STRETCH		0x152000
 	NvRegRxDeferral = 0xA4,
 #define NVREG_RX_DEFERRAL_DEFAULT	0x16
 	NvRegMacAddrA = 0xA8,
@@ -2785,6 +2789,7 @@ static int nv_update_linkspeed(struct net_device *dev)
 	int retval = 0;
 	u32 control_1000, status_1000, phyreg, pause_flags, txreg;
 	u32 txrxFlags = 0;
+	u32 phy_exp;
 
 	/* BMSR_LSTATUS is latched, read it twice:
 	 * we want the current value.
@@ -2912,13 +2917,25 @@ set_speed:
 		phyreg |= PHY_1000;
 	writel(phyreg, base + NvRegPhyInterface);
 
+	phy_exp = mii_rw(dev, np->phyaddr, MII_EXPANSION, MII_READ) & EXPANSION_NWAY; /* autoneg capable */
 	if (phyreg & PHY_RGMII) {
-		if ((np->linkspeed & NVREG_LINKSPEED_MASK) == NVREG_LINKSPEED_1000)
+		if ((np->linkspeed & NVREG_LINKSPEED_MASK) == NVREG_LINKSPEED_1000) {
 			txreg = NVREG_TX_DEFERRAL_RGMII_1000;
-		else
-			txreg = NVREG_TX_DEFERRAL_RGMII_10_100;
+		} else {
+			if (!phy_exp && !np->duplex && (np->driver_data & DEV_HAS_COLLISION_FIX)) {
+				if ((np->linkspeed & NVREG_LINKSPEED_MASK) == NVREG_LINKSPEED_10)
+					txreg = NVREG_TX_DEFERRAL_RGMII_STRETCH_10;
+				else
+					txreg = NVREG_TX_DEFERRAL_RGMII_STRETCH_100;
+			} else {
+				txreg = NVREG_TX_DEFERRAL_RGMII_10_100;
+			}
+		}
 	} else {
-		txreg = NVREG_TX_DEFERRAL_DEFAULT;
+		if (!phy_exp && !np->duplex && (np->driver_data & DEV_HAS_COLLISION_FIX))
+			txreg = NVREG_TX_DEFERRAL_MII_STRETCH;
+		else
+			txreg = NVREG_TX_DEFERRAL_DEFAULT;
 	}
 	writel(txreg, base + NvRegTxDeferral);
 
@@ -5615,51 +5632,51 @@ static struct pci_device_id pci_tbl[] = {
 	},
 	{	/* MCP73 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_28),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP73 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_29),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP73 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_30),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP73 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_31),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_HIGH_DMA|DEV_HAS_POWER_CNTRL|DEV_HAS_MSI|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP77 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_32),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP77 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_33),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP77 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_34),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP77 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_35),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP79 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_36),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP79 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_37),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP79 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_38),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{	/* MCP79 Ethernet Controller */
 		PCI_DEVICE(PCI_VENDOR_ID_NVIDIA, PCI_DEVICE_ID_NVIDIA_NVENET_39),
-		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR,
+		.driver_data = DEV_NEED_TIMERIRQ|DEV_NEED_LINKTIMER|DEV_HAS_CHECKSUM|DEV_HAS_HIGH_DMA|DEV_HAS_MSI|DEV_HAS_POWER_CNTRL|DEV_HAS_PAUSEFRAME_TX|DEV_HAS_STATISTICS_V2|DEV_HAS_TEST_EXTENDED|DEV_HAS_MGMT_UNIT|DEV_HAS_CORRECT_MACADDR|DEV_HAS_COLLISION_FIX,
 	},
 	{0,},
 };