[PATCH net] net: enetc: make sure all traffic classes can send large frames

From: Vladimir Oltean <vladimir.oltean@nxp.com>
To: netdev@vger.kernel.org, Jakub Kicinski <kuba@kernel.org>,
	"David S. Miller" <davem@davemloft.net>
Cc: Claudiu Manoil <claudiu.manoil@nxp.com>,
	Richie Pearn <richard.pearn@nxp.com>,
	Camelia Groza <camelia.groza@nxp.com>, Po Liu <po.liu@nxp.com>
Subject: [PATCH net] net: enetc: make sure all traffic classes can send large frames
Date: Wed, 20 Oct 2021 20:33:40 +0300	[thread overview]
Message-ID: <20211020173340.1089992-1-vladimir.oltean@nxp.com> (raw)

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>
---
 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 ead2b93bf614..64f92770691f 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);
-- 
2.25.1

