From b1ce3e60c80ddda0f9818ddb2a9541cbbee01e2e Mon Sep 17 00:00:00 2001
From: Jonathan McDowell <noodles@earth.li>
Date: Wed, 12 Aug 2020 20:37:23 +0100
Subject: [PATCH 5/6] net: ethernet: stmmac: Disable hardware multicast filter
Git-commit: df43dd526e6609769ae513a81443c7aa727c8ca3
References: git-fixes
Patch-mainline: v5.9-rc1

The IPQ806x does not appear to have a functional multicast ethernet
address filter. This was observed as a failure to correctly receive IPv6
packets on a LAN to the all stations address. Checking the vendor driver
shows that it does not attempt to enable the multicast filter and
instead falls back to receiving all multicast packets, internally
setting ALLMULTI.

Use the new fallback support in the dwmac1000 driver to correctly
achieve the same with the mainline IPQ806x driver. Confirmed to fix IPv6
functionality on an RB3011 router.

Cc: stable@vger.kernel.org
Signed-off-by: Jonathan McDowell <noodles@earth.li>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
 drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
index 6ae13dc19510..4d29b29af670 100644
--- a/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
+++ b/drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.c
@@ -338,6 +338,7 @@ static int ipq806x_gmac_probe(struct platform_device *pdev)
 	plat_dat->has_gmac = true;
 	plat_dat->bsp_priv = gmac;
 	plat_dat->fix_mac_speed = ipq806x_gmac_fix_mac_speed;
+	plat_dat->multicast_filter_bins = 0;
 
 	err = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
 	if (err)
-- 
2.16.4