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 35C51C678DB for ; Sat, 4 Mar 2023 13:45:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229567AbjCDNpS (ORCPT ); Sat, 4 Mar 2023 08:45:18 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43512 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229445AbjCDNpP (ORCPT ); Sat, 4 Mar 2023 08:45:15 -0500 Received: from fudo.makrotopia.org (fudo.makrotopia.org [IPv6:2a07:2ec0:3002::71]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 765AF18168; Sat, 4 Mar 2023 05:45:12 -0800 (PST) Received: from local by fudo.makrotopia.org with esmtpsa (TLS1.3:TLS_AES_256_GCM_SHA384:256) (Exim 4.96) (envelope-from ) id 1pYSC6-0006XR-1P; Sat, 04 Mar 2023 14:45:02 +0100 Date: Sat, 4 Mar 2023 13:43:20 +0000 From: Daniel Golle To: netdev@vger.kernel.org, linux-mediatek@lists.infradead.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Russell King , Heiner Kallweit , Lorenzo Bianconi , Mark Lee , John Crispin , Felix Fietkau , AngeloGioacchino Del Regno , Matthias Brugger , DENG Qingfang , Landen Chao , Sean Wang , Paolo Abeni , Jakub Kicinski , Eric Dumazet , "David S. Miller" , Vladimir Oltean , Florian Fainelli , Andrew Lunn , Vladimir Oltean Cc: =?iso-8859-1?Q?Bj=F8rn?= Mork Subject: [PATCH net] net: ethernet: mtk_eth_soc: fix RX data corruption issue Message-ID: <138da2735f92c8b6f8578ec2e5a794ee515b665f.1677937317.git.daniel@makrotopia.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Fix data corruption issue with SerDes connected PHYs operating at 1.25 Gbps speed where we could previously observe about 30% packet loss while the bad packet counter was increasing. As almost all boards with MediaTek MT7622 or MT7986 use either the MT7531 switch IC operating at 3.125Gbps SerDes rate or single-port PHYs using rate-adaptation to 2500Base-X mode, this issue only got exposed now when we started trying to use SFP modules operating with 1.25 Gbps with the BananaPi R3 board. The fix is to set bit 12 which disables the RX FIFO clear function when setting up MAC MCR, MediaTek SDK did the same change stating: "If without this patch, kernel might receive invalid packets that are corrupted by GMAC."[1] [1]: https://git01.mediatek.com/plugins/gitiles/openwrt/feeds/mtk-openwrt-feeds/+/d8a2975939a12686c4a95c40db21efdc3f821f63 Fixes: 42c03844e93d ("net-next: mediatek: add support for MediaTek MT7622 SoC") Tested-by: Bj?rn Mork Signed-off-by: Daniel Golle --- drivers/net/ethernet/mediatek/mtk_eth_soc.c | 3 ++- drivers/net/ethernet/mediatek/mtk_eth_soc.h | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.c b/drivers/net/ethernet/mediatek/mtk_eth_soc.c index 14be6ea51b88..3cb43623d3db 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.c +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.c @@ -616,7 +616,8 @@ static int mtk_mac_finish(struct phylink_config *config, unsigned int mode, mcr_cur = mtk_r32(mac->hw, MTK_MAC_MCR(mac->id)); mcr_new = mcr_cur; mcr_new |= MAC_MCR_IPG_CFG | MAC_MCR_FORCE_MODE | - MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK; + MAC_MCR_BACKOFF_EN | MAC_MCR_BACKPR_EN | MAC_MCR_FORCE_LINK | + MAC_MCR_RX_FIFO_CLR_DIS; /* Only update control register when needed! */ if (mcr_new != mcr_cur) diff --git a/drivers/net/ethernet/mediatek/mtk_eth_soc.h b/drivers/net/ethernet/mediatek/mtk_eth_soc.h index afc9d52e79bf..b65de174c3d9 100644 --- a/drivers/net/ethernet/mediatek/mtk_eth_soc.h +++ b/drivers/net/ethernet/mediatek/mtk_eth_soc.h @@ -397,6 +397,7 @@ #define MAC_MCR_FORCE_MODE BIT(15) #define MAC_MCR_TX_EN BIT(14) #define MAC_MCR_RX_EN BIT(13) +#define MAC_MCR_RX_FIFO_CLR_DIS BIT(12) #define MAC_MCR_BACKOFF_EN BIT(9) #define MAC_MCR_BACKPR_EN BIT(8) #define MAC_MCR_FORCE_RX_FC BIT(5) base-commit: 528125268588a18a2f257002af051b62b14bb282 -- 2.39.2