bnx2x: Fix intermittent long KR2 link up time

When a KR2 device is connected to a KR link-partner, sometimes it requires
disabling KR2 for the link to come up. To get a KR2 link up later, in case no
base pages are seen, the KR2 is restored. The problem was that some link
partners cleared their advertised BP/NP after around two seconds, causing the
driver to disable/enable KR2 link all the time.
The fix was to wait at least 5 seconds before checking KR2 recovery.

Signed-off-by: Yaniv Rosner <yanivr@broadcom.com>
Signed-off-by: Eilon Greenstein <eilong@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 13 insertions, 1 deletions

diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
index 31c5787970db..00ac4932f4c4 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.c
@@ -12527,6 +12527,7 @@ int bnx2x_phy_init(struct link_params *params, struct link_vars *vars)
         vars->flow_ctrl = BNX2X_FLOW_CTRL_NONE;
         vars->mac_type = MAC_TYPE_NONE;
         vars->phy_flags = 0;
+        vars->check_kr2_recovery_cnt = 0;
         /* Driver opens NIG-BRB filters */
         bnx2x_set_rx_filter(params, 1);
         /* Check if link flap can be avoided */
@@ -13411,6 +13412,7 @@ static void bnx2x_disable_kr2(struct link_params *params,
         vars->link_attr_sync &= ~LINK_ATTR_SYNC_KR2_ENABLE;
         bnx2x_update_link_attr(params, vars->link_attr_sync);
 
+        vars->check_kr2_recovery_cnt = CHECK_KR2_RECOVERY_CNT;
         /* Restart AN on leading lane */
         bnx2x_warpcore_restart_AN_KR(phy, params);
 }
@@ -13439,6 +13441,15 @@ static void bnx2x_check_kr2_wa(struct link_params *params,
                 return;
         }
 
+        /* Once KR2 was disabled, wait 5 seconds before checking KR2 recovery
+         * since some switches tend to reinit the AN process and clear the
+         * advertised BP/NP after ~2 seconds causing the KR2 to be disabled
+         * and recovered many times
+         */
+        if (vars->check_kr2_recovery_cnt > 0) {
+                vars->check_kr2_recovery_cnt--;
+                return;
+        }
         lane = bnx2x_get_warpcore_lane(phy, params);
         CL22_WR_OVER_CL45(bp, phy, MDIO_REG_BANK_AER_BLOCK,
                           MDIO_AER_BLOCK_AER_REG, lane);
diff --git a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.h b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.h
index be5c195d03dd..f92fcf71be04 100644
--- a/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.h
+++ b/drivers/net/ethernet/broadcom/bnx2x/bnx2x_link.h
@@ -342,7 +342,8 @@ struct link_vars {
         u32 link_status;
         u32 eee_status;
         u8 fault_detected;
-        u8 rsrv1;
+        u8 check_kr2_recovery_cnt;
+#define CHECK_KR2_RECOVERY_CNT  5
         u16 periodic_flags;
 #define PERIODIC_FLAGS_LINK_EVENT       0x0001