Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Rasmus Villemoes <linux@rasmusvillemoes.dk>
To:     Joakim Zhang <qiangqing.zhang@nxp.com>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Dumazet <edumazet@google.com>,
        Jakub Kicinski <kuba@kernel.org>,
        Paolo Abeni <pabeni@redhat.com>
Cc:     Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        netdev@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] net: fec: don't reset irq coalesce settings to defaults on "ip link up"
Date:   Wed, 23 Nov 2022 14:38:52 +0100
Message-Id: <20221123133853.1822415-1-linux@rasmusvillemoes.dk>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Currently, when a FEC device is brought up, the irq coalesce settings
are reset to their default values (1000us, 200 frames). That's
unexpected, and breaks for example use of an appropriate .link file to
make systemd-udev apply the desired
settings (https://www.freedesktop.org/software/systemd/man/systemd.link.html),
or any other method that would do a one-time setup during early boot.

Refactor the code so that fec_restart() instead uses
fec_enet_itr_coal_set(), which simply applies the settings that are
stored in the private data, and initialize that private data with the
default values.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
---
 drivers/net/ethernet/freescale/fec_main.c | 22 ++++++----------------
 1 file changed, 6 insertions(+), 16 deletions(-)

diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c
index f623c12eaf95..2ca2b61b451f 100644
--- a/drivers/net/ethernet/freescale/fec_main.c
+++ b/drivers/net/ethernet/freescale/fec_main.c
@@ -74,7 +74,7 @@
 #include "fec.h"
 
 static void set_multicast_list(struct net_device *ndev);
-static void fec_enet_itr_coal_init(struct net_device *ndev);
+static void fec_enet_itr_coal_set(struct net_device *ndev);
 
 #define DRIVER_NAME	"fec"
 
@@ -1220,8 +1220,7 @@ fec_restart(struct net_device *ndev)
 		writel(0, fep->hwp + FEC_IMASK);
 
 	/* Init the interrupt coalescing */
-	fec_enet_itr_coal_init(ndev);
-
+	fec_enet_itr_coal_set(ndev);
 }
 
 static int fec_enet_ipc_handle_init(struct fec_enet_private *fep)
@@ -2856,19 +2855,6 @@ static int fec_enet_set_coalesce(struct net_device *ndev,
 	return 0;
 }
 
-static void fec_enet_itr_coal_init(struct net_device *ndev)
-{
-	struct ethtool_coalesce ec;
-
-	ec.rx_coalesce_usecs = FEC_ITR_ICTT_DEFAULT;
-	ec.rx_max_coalesced_frames = FEC_ITR_ICFT_DEFAULT;
-
-	ec.tx_coalesce_usecs = FEC_ITR_ICTT_DEFAULT;
-	ec.tx_max_coalesced_frames = FEC_ITR_ICFT_DEFAULT;
-
-	fec_enet_set_coalesce(ndev, &ec, NULL, NULL);
-}
-
 static int fec_enet_get_tunable(struct net_device *netdev,
 				const struct ethtool_tunable *tuna,
 				void *data)
@@ -3623,6 +3609,10 @@ static int fec_enet_init(struct net_device *ndev)
 	fep->rx_align = 0x3;
 	fep->tx_align = 0x3;
 #endif
+	fep->rx_pkts_itr = FEC_ITR_ICFT_DEFAULT;
+	fep->tx_pkts_itr = FEC_ITR_ICFT_DEFAULT;
+	fep->rx_time_itr = FEC_ITR_ICTT_DEFAULT;
+	fep->tx_time_itr = FEC_ITR_ICTT_DEFAULT;
 
 	/* Check mask of the streaming and coherent API */
 	ret = dma_set_mask_and_coherent(&fep->pdev->dev, DMA_BIT_MASK(32));
-- 
2.37.2