From patchwork Thu Dec 21 00:02:22 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Linus Walleij X-Patchwork-Id: 13500837 X-Patchwork-Delegate: kuba@kernel.org Received: from mail-lf1-f45.google.com (mail-lf1-f45.google.com [209.85.167.45]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D85AF446A2 for ; Thu, 21 Dec 2023 00:02:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linaro.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="d6YR8+uH" Received: by mail-lf1-f45.google.com with SMTP id 2adb3069b0e04-50dfac6c0beso323540e87.2 for ; Wed, 20 Dec 2023 16:02:45 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1703116964; x=1703721764; darn=vger.kernel.org; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:from:to:cc:subject:date:message-id :reply-to; bh=lJLMGs1lZHtbdX/Mvsz/3hJzF7Azi3GTCJ3LJqHm/1E=; b=d6YR8+uH8jZga/zOP4TqUCaqmkn8le5qm03iE8EiYWFDo4ML1cJgFKw3pS+vgI2YIF zhx4/9mC2zyHU7Uu30o+DOPYDWA7f0Gega+kxM+9GUp+3sitPvr9FJi3Se7IHCmDFB2G CspJG9MBHgqYjW07sze0cty0XWGLvgw6tfDl5G+4O9LJ9mWsbWtCQL5IsMrUYvNRoA2N gqRFwe89MuW1tWjwbflh/14H6ctBltRH2GGA56rcVAVIm23Ub8K4m58SKpJ697yYyjfF YcYDKR3ffZl4bozIySbV5BLcfDvK8zxRXFTHcbpo0/l1j0jWjawqd6/jJZyWbUk8otMO 7v6Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1703116964; x=1703721764; h=cc:to:in-reply-to:references:message-id:content-transfer-encoding :mime-version:subject:date:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=lJLMGs1lZHtbdX/Mvsz/3hJzF7Azi3GTCJ3LJqHm/1E=; b=HkNF34I0h+85m6n+8qmrJAk3U0R9YI3ik8UEjm+2a0VTpgE50Msa5djpYg2gV84uRC 2FUEsmMNcO7UUr2gyk/lRLE+1ZtTZoUiX02c4riWHbjnOmYPC/EkMQuDi1hSHgN1LVQB UBohgFxPrctTZSV/oqH1Mt5yTS4FpG5AdgdUsyhxbVGrOWpzOp5Ll9jeoLrWpCgaEPfs VnW/m787ALzjawoxIxXK5CzTJbGX/CjSPwi079ZHrN2j0id3c4hdinaROFl7g3Q97FdF QiatvuETN82f978SWLWtr7Ye4ve2nwFgUEAqKcV6B+K6MxbcewSMCaw45EQa9u9lVmcr jpog== X-Gm-Message-State: AOJu0Yyevo495k73/B+d+9iLXnkZkenjXjeb9LGgFnnEI1xTRvdzbc3r D8JZ97XkT4eT2BbcdIbt1dnhZw== X-Google-Smtp-Source: AGHT+IE1WX0Y0fiv3yUhbmICABCtXC8/5OkNumN66LfZib/JXWiHTn/R1K783d8eGgvHPWesuzXGiQ== X-Received: by 2002:a05:6512:1584:b0:50e:10e8:d544 with SMTP id bp4-20020a056512158400b0050e10e8d544mr9221601lfb.68.1703116963568; Wed, 20 Dec 2023 16:02:43 -0800 (PST) Received: from [127.0.1.1] ([85.235.12.238]) by smtp.gmail.com with ESMTPSA id v26-20020a19741a000000b0050e4ac5bf5asm100321lfe.284.2023.12.20.16.02.42 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 20 Dec 2023 16:02:43 -0800 (PST) From: Linus Walleij Date: Thu, 21 Dec 2023 01:02:22 +0100 Subject: [PATCH net v3 3/3] net: ethernet: cortina: Bypass checksumming engine of alien ethertypes Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Message-Id: <20231221-new-gemini-ethernet-regression-v3-3-a96b4374bfe8@linaro.org> References: <20231221-new-gemini-ethernet-regression-v3-0-a96b4374bfe8@linaro.org> In-Reply-To: <20231221-new-gemini-ethernet-regression-v3-0-a96b4374bfe8@linaro.org> To: Hans Ulli Kroll , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni Cc: netdev@vger.kernel.org, Linus Walleij X-Mailer: b4 0.12.4 X-Patchwork-Delegate: kuba@kernel.org We had workarounds were the ethernet checksumming engine would be bypassed for larger frames, this fixed devices using DSA, but regressed devices where the ethernet was connected directly to a PHY. The devices with a PHY connected directly can't handle large frames either way, with or without bypass. Looking at the size of the frame is probably just wrong. Rework the workaround such that we just bypass the checksumming engine if the ethertype inside the actual frame is something else than 0x0800 (IPv4) or 0x86dd (IPv6). These are the only frames the checksumming engine can actually handle. VLAN framing (0x8100) also works fine. We can't inspect skb->protocol because DSA frames will sometimes have a custom ethertype despite skb->protocol is e.g. 0x0800. After this both devices with direct ethernet attached such as D-Link DNS-313 and devices with a DSA switch with a custom ethertype such as D-Link DIR-685 work fine. Fixes: d4d0c5b4d279 ("net: ethernet: cortina: Handle large frames") Signed-off-by: Linus Walleij --- drivers/net/ethernet/cortina/gemini.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-) diff --git a/drivers/net/ethernet/cortina/gemini.c b/drivers/net/ethernet/cortina/gemini.c index ecc247acac39..6d153eba8e81 100644 --- a/drivers/net/ethernet/cortina/gemini.c +++ b/drivers/net/ethernet/cortina/gemini.c @@ -29,6 +29,7 @@ #include #include #include +#include #include #include #include @@ -1143,6 +1144,7 @@ static int gmac_map_tx_bufs(struct net_device *netdev, struct sk_buff *skb, skb_frag_t *skb_frag; dma_addr_t mapping; unsigned short mtu; + u16 ethertype; void *buffer; mtu = ETH_HLEN; @@ -1158,7 +1160,24 @@ static int gmac_map_tx_bufs(struct net_device *netdev, struct sk_buff *skb, word3 |= mtu; } - if (skb->ip_summed == CHECKSUM_PARTIAL) { + /* Dig out the the ethertype actually in the buffer and not what the + * protocol claims to be. This is the raw data that the checksumming + * offload engine will have to deal with. + */ + ethertype = skb_eth_raw_ethertype(skb); + /* This is the only VLAN type supported by this hardware so check for + * that: the checksumming engine can handle IP and IPv6 inside 802.1Q. + */ + if (ethertype == ETH_P_8021Q) + ethertype = vlan_get_protocol(skb); + + if (ethertype != ETH_P_IP && ethertype != ETH_P_IPV6) { + /* Hardware offloaded checksumming isn't working on non-IP frames. + * This happens for example on some DSA switches using a custom + * ethertype. Just bypass the engine for those. + */ + word1 |= TSS_BYPASS_BIT; + } else if (skb->ip_summed == CHECKSUM_PARTIAL) { int tcp = 0; /* We do not switch off the checksumming on non TCP/UDP