From e378f4967c8edd64c680f2e279cb646ee06b6f2d Mon Sep 17 00:00:00 2001
From: Vladimir Oltean <vladimir.oltean@nxp.com>
Date: Wed, 20 Oct 2021 20:33:40 +0300
Subject: [PATCH] net: enetc: make sure all traffic classes can send large
 frames

The enetc driver does not implement .ndo_change_mtu, instead it
configures the MAC register field PTC{Traffic Class}MSDUR[MAXSDU]
statically to a large value during probe time.

The driver used to configure only the max SDU for traffic class 0, and
that was fine while the driver could only use traffic class 0. But with
the introduction of mqprio, sending a large frame into any other TC than
0 is broken.

This patch fixes that by replicating per traffic class the static
configuration done in enetc_configure_port_mac().

Fixes: cbe9e835946f ("enetc: Enable TC offloading with mqprio")
Reported-by: Richie Pearn <richard.pearn@nxp.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: <Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://lore.kernel.org/r/20211020173340.1089992-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---
 drivers/net/ethernet/freescale/enetc/enetc_pf.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/freescale/enetc/enetc_pf.c b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
index 4c977dfc44f0d..d522bd5c90b49 100644
--- a/drivers/net/ethernet/freescale/enetc/enetc_pf.c
+++ b/drivers/net/ethernet/freescale/enetc/enetc_pf.c
@@ -517,10 +517,13 @@ static void enetc_port_si_configure(struct enetc_si *si)
 
 static void enetc_configure_port_mac(struct enetc_hw *hw)
 {
+	int tc;
+
 	enetc_port_wr(hw, ENETC_PM0_MAXFRM,
 		      ENETC_SET_MAXFRM(ENETC_RX_MAXFRM_SIZE));
 
-	enetc_port_wr(hw, ENETC_PTCMSDUR(0), ENETC_MAC_MAXFRM_SIZE);
+	for (tc = 0; tc < 8; tc++)
+		enetc_port_wr(hw, ENETC_PTCMSDUR(tc), ENETC_MAC_MAXFRM_SIZE);
 
 	enetc_port_wr(hw, ENETC_PM0_CMD_CFG, ENETC_PM0_CMD_PHY_TX_EN |
 		      ENETC_PM0_CMD_TXP	| ENETC_PM0_PROMISC);