tg3: Prevent tx BD corruption

This patch prevents a tx BD corruption bug by preventing the device from
powering down the PLL from L1 if the link speed is 10Mbps or 100Mbps.

The same bits are also used to prevent a system hang during chip reset
resulting from a complicated set of events that ultimately leads to
PCIe block register corruption.

Signed-off-by: Matt Carlson <mcarlson@broadcom.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Reviewed-by: Benjamin Li <benli@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index c613cbb..bb8591e 100644
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -866,6 +866,7 @@
 #define  RCVLPC_STATSCTRL_ENABLE	 0x00000001
 #define  RCVLPC_STATSCTRL_FASTUPD	 0x00000002
 #define RCVLPC_STATS_ENABLE		0x00002018
+#define  RCVLPC_STATSENAB_ASF_FIX	 0x00000002
 #define  RCVLPC_STATSENAB_DACK_FIX	 0x00040000
 #define  RCVLPC_STATSENAB_LNGBRST_RFIX	 0x00400000
 #define RCVLPC_STATS_INCMASK		0x0000201c
@@ -1704,7 +1705,12 @@
 #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
-/* 0x7d2c --> 0x7e70 unused */
+/* 0x7d2c --> 0x7d54 unused */
+
+#define TG3_PCIE_LNKCTL			0x00007d54
+#define  TG3_PCIE_LNKCTL_L1_PLL_PD_EN	 0x00000008
+#define  TG3_PCIE_LNKCTL_L1_PLL_PD_DIS	 0x00000080
+/* 0x7d58 --> 0x7e70 unused */
 
 #define TG3_PCIE_EIDLE_DELAY		0x00007e70
 #define  TG3_PCIE_EIDLE_DELAY_MASK	 0x0000001f
@@ -2650,6 +2656,7 @@
 #define TG3_FLG3_PHY_ENABLE_APD		0x00001000
 #define TG3_FLG3_5755_PLUS		0x00002000
 #define TG3_FLG3_NO_NVRAM		0x00004000
+#define TG3_FLG3_TOGGLE_10_100_L1PLLPD	0x00008000
 
 	struct timer_list		timer;
 	u16				timer_counter;