From a626e8478b18de4fdee0e6d13975cea2b23efea5 Mon Sep 17 00:00:00 2001
From: Don Skidmore <donald.c.skidmore@intel.com>
Date: Thu, 11 Feb 2010 04:13:49 +0000
Subject: [PATCH] ixgbe: Fix - Do not allow Rx FC on 82598 at 1G due to errata
The 82598 has an erratum that receipt of pause frames at 1G
could lead to a Tx Hang. To avoid this this patch disables
Rx FC while at 1G speed for all 82598 parts.
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/ixgbe/ixgbe_82598.c | 22 ++++++++++++++++++++++
1 file changed, 22 insertions(+)
diff --git a/drivers/net/ixgbe/ixgbe_82598.c b/drivers/net/ixgbe/ixgbe_82598.c
index 3103f4165311e..35a06b47587bd 100644
--- a/drivers/net/ixgbe/ixgbe_82598.c
+++ b/drivers/net/ixgbe/ixgbe_82598.c
@@ -357,12 +357,34 @@ static s32 ixgbe_fc_enable_82598(struct ixgbe_hw *hw, s32 packetbuf_num)
u32 fctrl_reg;
u32 rmcs_reg;
u32 reg;
+ u32 link_speed = 0;
+ bool link_up;
#ifdef CONFIG_DCB
if (hw->fc.requested_mode == ixgbe_fc_pfc)
goto out;
#endif /* CONFIG_DCB */
+ /*
+ * On 82598 having Rx FC on causes resets while doing 1G
+ * so if it's on turn it off once we know link_speed. For
+ * more details see 82598 Specification update.
+ */
+ hw->mac.ops.check_link(hw, &link_speed, &link_up, false);
+ if (link_up && link_speed == IXGBE_LINK_SPEED_1GB_FULL) {
+ switch (hw->fc.requested_mode) {
+ case ixgbe_fc_full:
+ hw->fc.requested_mode = ixgbe_fc_tx_pause;
+ break;
+ case ixgbe_fc_rx_pause:
+ hw->fc.requested_mode = ixgbe_fc_none;
+ break;
+ default:
+ /* no change */
+ break;
+ }
+ }
+
/* Negotiate the fc mode to use */
ret_val = ixgbe_fc_autoneg(hw);
if (ret_val)
--
2.30.2