From: Michael Chan <michael.chan@broadcom.com>
Date: Wed, 19 Dec 2018 13:46:50 -0500
Subject: bnxt_en: Fix ethtool self-test loopback.
Patch-mainline: v4.20
Git-commit: 84404d5fd5858588bbf694b0300dbc6310d02737
References: bsc#1104745 FATE#325918

The current code has 2 problems.  It assumes that the RX ring for
the loopback packet is combined with the TX ring.  This is not
true if the ethtool channels are set to non-combined mode.  The
second problem is that it won't work on 57500 chips without
adjusting the logic to get the proper completion ring (cpr) pointer.
Fix both issues by locating the proper cpr pointer through the RX
ring.

Fixes: e44758b78ae8 ("bnxt_en: Use bnxt_cp_ring_info struct pointer as parameter for RX path.")
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

--- a/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
+++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_ethtool.c
@@ -2572,6 +2572,7 @@ static int bnxt_poll_loopback(struct bnx
 static int bnxt_run_loopback(struct bnxt *bp)
 {
 	struct bnxt_tx_ring_info *txr = &bp->tx_ring[0];
+	struct bnxt_rx_ring_info *rxr = &bp->rx_ring[0];
 	struct bnxt_cp_ring_info *cpr;
 	int pkt_size, i = 0;
 	struct sk_buff *skb;
@@ -2579,7 +2580,9 @@ static int bnxt_run_loopback(struct bnxt
 	u8 *data;
 	int rc;
 
-	cpr = &txr->bnapi->cp_ring;
+	cpr = &rxr->bnapi->cp_ring;
+	if (bp->flags & BNXT_FLAG_CHIP_P5)
+		cpr = cpr->cp_ring_arr[BNXT_RX_HDL];
 	pkt_size = min(bp->dev->mtu + ETH_HLEN, bp->rx_copy_thresh);
 	skb = netdev_alloc_skb(bp->dev, pkt_size);
 	if (!skb)