From patchwork Sun Oct 23 18:48:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Horatiu Vultur X-Patchwork-Id: 13016418 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B569EFA373F for ; Sun, 23 Oct 2022 18:45:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230435AbiJWSpY (ORCPT ); Sun, 23 Oct 2022 14:45:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40378 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230395AbiJWSpT (ORCPT ); Sun, 23 Oct 2022 14:45:19 -0400 Received: from esa.microchip.iphmx.com (esa.microchip.iphmx.com [68.232.154.123]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5618E3FEEC; Sun, 23 Oct 2022 11:45:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=microchip.com; i=@microchip.com; q=dns/txt; s=mchp; t=1666550719; x=1698086719; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=eVE2lQ5w+2D1pFZYr6+909z4xn/w37Zq+2kgclL7XFo=; b=WUrNW6X8J04JeyR55yOjf+DQNgeEAkGx9wjCCcHtw60YaeIiPyyGWOtQ dQdMwhXgFK5G8PsmjoK/dkI/HcJpaZI7iyfcwSq4NRAPZRTx7/ZrJxFKU vKGpBR8JMElASA1gQG/EywrruvyCzowwBfXtWiZcA2/pMi2pwHuq1KHaZ 23ZLI9PL1x4nAUcrSV6CLKAdQ0Sijbx0oa6OmEYeVdQfYJ30JgbSAP7bA 6wk7wNwmb2/oTAkme5tnciEn6gZ+Xn97jXADiLnSKDQPq3X8c0/9E7hCW 2KqBkAMOyP+xDl6VV/jAN06bhqsbF7ys/rJssCiG2IEWCBp4meoiKnYRl A==; X-IronPort-AV: E=Sophos;i="5.95,207,1661842800"; d="scan'208";a="180146172" Received: from unknown (HELO email.microchip.com) ([170.129.1.10]) by esa4.microchip.iphmx.com with ESMTP/TLS/AES256-SHA256; 23 Oct 2022 11:45:18 -0700 Received: from chn-vm-ex04.mchp-main.com (10.10.85.152) by chn-vm-ex01.mchp-main.com (10.10.85.143) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.12; Sun, 23 Oct 2022 11:45:17 -0700 Received: from soft-dev3-1.microsemi.net (10.10.115.15) by chn-vm-ex04.mchp-main.com (10.10.85.152) with Microsoft SMTP Server id 15.1.2507.12 via Frontend Transport; Sun, 23 Oct 2022 11:45:16 -0700 From: Horatiu Vultur To: , CC: , , , , , Horatiu Vultur Subject: [PATCH net 3/3] net: lan966x: Fix FDMA when MTU is changed Date: Sun, 23 Oct 2022 20:48:38 +0200 Message-ID: <20221023184838.4128061-4-horatiu.vultur@microchip.com> X-Mailer: git-send-email 2.38.0 In-Reply-To: <20221023184838.4128061-1-horatiu.vultur@microchip.com> References: <20221023184838.4128061-1-horatiu.vultur@microchip.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org When MTU is changed, FDMA is required to calculate what is the maximum size of the frame that it can received. So it can calculate what is the page order needed to allocate for the received frames. The first problem was that, when the max MTU was calculated it was reading the value from dev and not from HW, so in this way it was missing L2 header + the FCS. The other problem was that once the skb is created using __build_skb_around, it would reserve some space for skb_shared_info. So if we received a frame which size is at the limit of the page order then the creating will failed because it would not have space to put all the data. Fixes: 2ea1cbac267e ("net: lan966x: Update FDMA to change MTU.") Signed-off-by: Horatiu Vultur --- drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c | 7 +++++-- drivers/net/ethernet/microchip/lan966x/lan966x_main.c | 2 +- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c index a42035cec611c..5a5603f9e9fd3 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_fdma.c @@ -668,12 +668,14 @@ static int lan966x_fdma_get_max_mtu(struct lan966x *lan966x) int i; for (i = 0; i < lan966x->num_phys_ports; ++i) { + struct lan966x_port *port; int mtu; - if (!lan966x->ports[i]) + port = lan966x->ports[i]; + if (!port) continue; - mtu = lan966x->ports[i]->dev->mtu; + mtu = lan_rd(lan966x, DEV_MAC_MAXLEN_CFG(port->chip_port)); if (mtu > max_mtu) max_mtu = mtu; } @@ -733,6 +735,7 @@ int lan966x_fdma_change_mtu(struct lan966x *lan966x) max_mtu = lan966x_fdma_get_max_mtu(lan966x); max_mtu += IFH_LEN * sizeof(u32); + max_mtu += SKB_DATA_ALIGN(sizeof(struct skb_shared_info)); if (round_up(max_mtu, PAGE_SIZE) / PAGE_SIZE - 1 == lan966x->rx.page_order) diff --git a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c index b3070c3fcad0a..20ee5b28f70a5 100644 --- a/drivers/net/ethernet/microchip/lan966x/lan966x_main.c +++ b/drivers/net/ethernet/microchip/lan966x/lan966x_main.c @@ -395,7 +395,7 @@ static int lan966x_port_change_mtu(struct net_device *dev, int new_mtu) err = lan966x_fdma_change_mtu(lan966x); if (err) { - lan_wr(DEV_MAC_MAXLEN_CFG_MAX_LEN_SET(old_mtu), + lan_wr(DEV_MAC_MAXLEN_CFG_MAX_LEN_SET(LAN966X_HW_MTU(old_mtu)), lan966x, DEV_MAC_MAXLEN_CFG(port->chip_port)); dev->mtu = old_mtu; }