sfc: Make queue flushes more reliable

Increase the potential retry count for RX flushes from 5 to 100.

Stop polling the RX_DESC_PTR_TBL to infer that a flush might have
happened. Instead absolutely rely on the flush events, unless bug 7803
applies (Falcon rev A only).

To keep things quick, request flushes for every TX and RX queue up
front, and match up the events to requests.

Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
diff --git a/drivers/net/sfc/falcon.h b/drivers/net/sfc/falcon.h
index 30d61e4..be025ba 100644
--- a/drivers/net/sfc/falcon.h
+++ b/drivers/net/sfc/falcon.h
@@ -86,6 +86,7 @@
 extern int falcon_probe_nic(struct efx_nic *efx);
 extern int falcon_probe_resources(struct efx_nic *efx);
 extern int falcon_init_nic(struct efx_nic *efx);
+extern int falcon_flush_queues(struct efx_nic *efx);
 extern int falcon_reset_hw(struct efx_nic *efx, enum reset_type method);
 extern void falcon_remove_resources(struct efx_nic *efx);
 extern void falcon_remove_nic(struct efx_nic *efx);