[PATCH AUTOSEL 4.19 21/29] bnxt_en: Eliminate unintended link toggle during FW reset

From: Sasha Levin
Date: Fri Apr 01 2022 - 11:41:05 EST


From: Michael Chan <michael.chan@xxxxxxxxxxxx>

[ Upstream commit 7c492a2530c1f05441da541307c2534230dfd59b ]

If the flow control settings have been changed, a subsequent FW reset
may cause the ethernet link to toggle unnecessarily. This link toggle
will increase the down time by a few seconds.

The problem is caused by bnxt_update_phy_setting() detecting a false
mismatch in the flow control settings between the stored software
settings and the current FW settings after the FW reset. This mismatch
is caused by the AUTONEG bit added to link_info->req_flow_ctrl in an
inconsistent way in bnxt_set_pauseparam() in autoneg mode. The AUTONEG
bit should not be added to link_info->req_flow_ctrl.

Reviewed-by: Colin Winegarden <colin.winegarden@xxxxxxxxxxxx>
Reviewed-by: Pavan Chebbi <pavan.chebbi@xxxxxxxxxxxx>
Signed-off-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
index e75a47a9f511..deba77670b1c 100644
--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -1377,9 +1377,7 @@ static int bnxt_set_pauseparam(struct net_device *dev,
}

link_info->autoneg |= BNXT_AUTONEG_FLOW_CTRL;
- if (bp->hwrm_spec_code >= 0x10201)
- link_info->req_flow_ctrl =
- PORT_PHY_CFG_REQ_AUTO_PAUSE_AUTONEG_PAUSE;
+ link_info->req_flow_ctrl = 0;
} else {
/* when transition from auto pause to force pause,
* force a link change
--
2.34.1