From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6E9CFC4363A for ; Fri, 30 Oct 2020 12:36:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F0CAB2087E for ; Fri, 30 Oct 2020 12:36:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726307AbgJ3Mgz (ORCPT ); Fri, 30 Oct 2020 08:36:55 -0400 Received: from vps0.lunn.ch ([185.16.172.187]:54488 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725891AbgJ3Mgy (ORCPT ); Fri, 30 Oct 2020 08:36:54 -0400 Received: from andrew by vps0.lunn.ch with local (Exim 4.94) (envelope-from ) id 1kYTeC-004M8B-BO; Fri, 30 Oct 2020 13:36:48 +0100 Date: Fri, 30 Oct 2020 13:36:48 +0100 From: Andrew Lunn To: DENG Qingfang Cc: netdev , Felix Fietkau , John Crispin , Sean Wang , Mark Lee , Landen Chao , Jakub Kicinski , "David S . Miller" , Matthias Brugger , =?iso-8859-1?Q?Ren=E9?= van Dorst , David Woodhouse , Frank Wunderlich Subject: Re: [RFC PATCH net-next] net: ethernet: mediatek: support setting MTU Message-ID: <20201030123648.GA1017106@lunn.ch> References: <20201029063915.4287-1-dqfext@gmail.com> <20201029130147.GL933237@lunn.ch> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Fri, Oct 30, 2020 at 10:43:51AM +0800, DENG Qingfang wrote: > On Thu, Oct 29, 2020 at 9:02 PM Andrew Lunn wrote: > > > > On Thu, Oct 29, 2020 at 02:39:15PM +0800, DENG Qingfang wrote: > > > MT762x HW supports frame length up to 2048 (maximum length on GDM), > > > so allow setting MTU up to 2030. > > > > > > Signed-off-by: DENG Qingfang > > > --- > > > > > > I only tested this on MT7621, no sure if it is applicable for other SoCs > > > especially MT7628, which has an old IP. > > > > > > --- > > > drivers/net/ethernet/mediatek/mtk_eth_soc.c | 31 ++++++++++++++++++++- > > > drivers/net/ethernet/mediatek/mtk_eth_soc.h | 11 ++++++-- > > > 2 files changed, 38 insertions(+), 4 deletions(-) > > > > > > diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > > > index 6d2d60675ffd..a0c56d9be1d5 100644 > > > --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c > > > +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c > > > @@ -353,7 +353,7 @@ static void mtk_mac_config(struct phylink_config *config, unsigned int mode, > > > /* Setup gmac */ > > > mcr_cur = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id)); > > > mcr_new = mcr_cur; > > > - mcr_new |= MAC_MCR_MAX_RX_1536 | MAC_MCR_IPG_CFG | MAC_MCR_FORCE_MODE | > > > + mcr_new |= MAC_MCR_IPG_CFG | MAC_MCR_FORCE_MODE | > > > MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK; > > > > Since you no longer set MAC_MCR_MAX_RX_1536, what does the hardware > > default to? > > 2'b00, i.e. 1518 bytes. O.K, that fits the default for a netdev. > It is handled in net_device->max_mtu: > > eth->netdev[id]->max_mtu = MTK_MAX_RX_LENGTH - MTK_RX_ETH_HLEN; Cool. Reviewed-by: Andrew Lunn Andrew