From: Jakub Kicinski <jakub.kicinski@netronome.com>
Date: Tue, 27 Jun 2017 00:50:15 -0700
Subject: nfp: explicitly check if application FW is loaded
Patch-mainline: v4.13-rc1
Git-commit: d557ee6bdc6dc4df2ab8e00c2127120b4acbdfca
References: bsc#1055968

We support application FW being either loaded automatically at
boot from flash or (more commonly) by the driver from disk.
If FW is not found on disk and nothing is preloaded users are
faced with this unintuitive error:

nfp 0000:04:00.0: nfp: Failed to find PF symbol _pf0_net_bar0

We can do better.  Since we rely on symbol table being present -
check early if it could be correctly read out of from the device
and if not print a more informative message.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/netronome/nfp/nfp_net_main.c |   11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

--- a/drivers/net/ethernet/netronome/nfp/nfp_net_main.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_main.c
@@ -589,10 +589,7 @@ static int nfp_net_pci_map_mem(struct nf
 				   ctrl_bar_sz, &pf->data_vnic_bar);
 	if (IS_ERR(mem)) {
 		nfp_err(pf->cpp, "Failed to find data vNIC memory symbol\n");
-		err = PTR_ERR(mem);
-		if (!pf->fw_loaded && err == -ENOENT)
-			err = -EPROBE_DEFER;
-		return err;
+		return PTR_ERR(mem);
 	}
 
 	pf->mac_stats_mem = nfp_net_pf_map_rtsym(pf, "net.macstats",
@@ -786,6 +783,12 @@ int nfp_net_pci_probe(struct nfp_pf *pf)
 		return -EINVAL;
 	}
 
+	if (!pf->rtbl) {
+		nfp_err(pf->cpp, "No %s, giving up.\n",
+			pf->fw_loaded ? "symbol table" : "firmware found");
+		return -EPROBE_DEFER;
+	}
+
 	mutex_lock(&pf->lock);
 	pf->max_data_vnics = nfp_net_pf_get_num_ports(pf);
 	if ((int)pf->max_data_vnics < 0) {