tg3: Fix rx hang on MTU change with 5717/5719

This fixes a hang issue seen when changing the MTU size from 1500 MTU
to 9000 MTU on both 5717 and 5719 chips. In discussion with Broadcom,
they've indicated that these chipsets have the same phy as the 57766
chipset, so the same workarounds apply. This has been tested by IBM
on both Power 8 and Power 9 systems as well as by Broadcom on x86
hardware and has been confirmed to resolve the hang issue.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/broadcom/tg3.c b/drivers/net/ethernet/broadcom/tg3.c
index de51c2177d03b3cf9e4653226bd8901b1d29834e..d09c5a9c53b502788224102a6ae789cc42cc9b25 100644 (file)
--- a/drivers/net/ethernet/broadcom/tg3.c
+++ b/drivers/net/ethernet/broadcom/tg3.c
@@ -14225,7 +14225,9 @@ static int tg3_change_mtu(struct net_device *dev, int new_mtu)
        /* Reset PHY, otherwise the read DMA engine will be in a mode that
         * breaks all requests to 256 bytes.
         */
-       if (tg3_asic_rev(tp) == ASIC_REV_57766)
+       if (tg3_asic_rev(tp) == ASIC_REV_57766 ||
+           tg3_asic_rev(tp) == ASIC_REV_5717 ||
+           tg3_asic_rev(tp) == ASIC_REV_5719)
                reset_phy = true;
 
        err = tg3_restart_hw(tp, reset_phy);