tg3: Prevent send BD corruption

On rare occasions, send BD corruptions can occur.  This patch
fixes the problem by increasing the L1 entry threshold to 4
milliseconds.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/tg3.c

@@ -6717,6 +6717,13 @@ static int tg3_reset_hw(struct tg3 *tp, int reset_phy)
 		tw32(TG3_CPMU_HST_ACC, val);
 	}
 
+	if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_57780) {
+		val = tr32(PCIE_PWR_MGMT_THRESH) & ~PCIE_PWR_MGMT_L1_THRESH_MSK;
+		val |= PCIE_PWR_MGMT_EXT_ASPM_TMR_EN |
+		       PCIE_PWR_MGMT_L1_THRESH_4MS;
+		tw32(PCIE_PWR_MGMT_THRESH, val);
+	}
+
 	/* This works around an issue with Athlon chipsets on
 	 * B3 tigon3 silicon.  This bit has no effect on any
 	 * other revision.  But do not set this on PCI Express

drivers/net/tg3.h

@@ -1697,6 +1697,8 @@
 
 #define PCIE_PWR_MGMT_THRESH		0x00007d28
 #define PCIE_PWR_MGMT_L1_THRESH_MSK	 0x0000ff00
+#define PCIE_PWR_MGMT_L1_THRESH_4MS	 0x0000ff00
+#define PCIE_PWR_MGMT_EXT_ASPM_TMR_EN	 0x01000000
 
 
 /* OTP bit definitions */