fm10k: force link to remain down for at least a second on resume events

When we resume from an AER recovery with many active VFs, the PF sees
many spurious link up and link down events. Prevent this by delaying
link down for at least one second after the resume event.
Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Tested-by: Krishneil Singh <Krishneil.k.singh@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/fm10k/fm10k_pci.c

@@ -2158,6 +2158,10 @@ static int fm10k_handle_resume(struct fm10k_intfc *interface)
 	interface->host_ready = false;
 	fm10k_watchdog_host_not_ready(interface);
 
+	/* force link to stay down for a second to prevent link flutter */
+	interface->link_down_event = jiffies + (HZ);
+	set_bit(__FM10K_LINK_DOWN, &interface->state);
+
 	/* clear the service task disable bit to allow service task to start */
 	clear_bit(__FM10K_SERVICE_DISABLE, &interface->state);
 	fm10k_service_event_schedule(interface);