From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-02.galae.net (smtpout-02.galae.net [185.246.84.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 0E5103BAD90 for ; Tue, 28 Apr 2026 16:08:04 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.84.56 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777392488; cv=none; b=d4HkJ3Ga+p3so+m9Gmx8RAO9WjC11OfSajK10yl9Sx6JBv3MKlb9GkYRtJf/0oja0B9U6/nsdF2iaC2q5iYZHSiVO5Ai5egZnAMzJh9qePn+ZvfuYHhe54y80wHZUlldHWUNHHV2+3gpbpz/Y6XdguajcNUI6fQhyc6B6NtUmZA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777392488; c=relaxed/simple; bh=DOvjwCqRSTMuph9VfUSOH3Bnxl1XAy9dSaasLTePhRU=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=NU6tdz0SW8RPuEiDa5tFYVn4uxoOXZf4usGQmbP5jADep1q7BSyViVSi5x8vl5lIyzjnvELAIjaFZ0BshUX7sqh3p9bgi0pU5oHm/HiFmIY5yhEBdq9ZtqZCYUUKjz26XfIcc70WIYZfj6T9hIVScqLMElHxzGfPJ12E9bGTERI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=qPSztoZg; arc=none smtp.client-ip=185.246.84.56 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="qPSztoZg" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-02.galae.net (Postfix) with ESMTPS id 7B8E51A3472; Tue, 28 Apr 2026 16:08:03 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 4CA35601D0; Tue, 28 Apr 2026 16:08:03 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 9ED3E10728E5D; Tue, 28 Apr 2026 18:07:54 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1777392481; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=R7YnNrHkXr0z6CcnblvtQUE03jaxaAjhHUqCoIZWK3k=; b=qPSztoZgXx+kxLNzJum1hgHv4NAJeJDfINkViE9otpRTWo1Tif78POYWdHN2F/Bdfhfrzm 1ntwbF2ByJFgJmMVOSpK+czfI/tBWKMWfLQQzsy1OOYWSOAeBim5wKn1itEZ6A6pZSlMAw 0qGzC47poRHNgQr/8zCUGsyO2UiuEHgt3ZANU8gru1lBWXvi3Y7BFJ0ZRYX5Sao8QnnJSC nYqi7zKWGJK87MVruHV/yncpE/W5C6dQzAv9wHnT8irsBW6UpZwbvvkvmd8zM8tekHjfxZ OPmd39vhByGsk27HRvI3iFrkfgj/BHqOi0x/hkagWLqlx8QRqr/IKDV4o8O49g== Date: Tue, 28 Apr 2026 18:07:52 +0200 From: Herve Codina To: Daniel Machon Cc: Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Horatiu Vultur , Steen Hegelund , , "Alexei Starovoitov" , Daniel Borkmann , "Jesper Dangaard Brouer" , John Fastabend , Stanislav Fomichev , Arnd Bergmann , Greg Kroah-Hartman , Mohsin Bashir , , , Subject: Re: [PATCH net-next v2 00/13] net: lan966x: add support for PCIe FDMA Message-ID: <20260428180752.4e68fea8@bootlin.com> In-Reply-To: <20260428-lan966x-pci-fdma-v2-0-d3ec66e06202@microchip.com> References: <20260428-lan966x-pci-fdma-v2-0-d3ec66e06202@microchip.com> Organization: Bootlin X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-redhat-linux-gnu) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Last-TLS-Session-Version: TLSv1.3 Hi Daniel, all, On Tue, 28 Apr 2026 15:06:49 +0200 Daniel Machon wrote: > When lan966x operates as a PCIe endpoint, the driver currently uses > register-based I/O for frame injection and extraction. This approach is > functional but slow, topping out at around 33 Mbps on an Intel x86 host > with a lan966x PCIe card. > > This series adds FDMA (Frame DMA) support for the PCIe path. When > operating as a PCIe endpoint, the internal FDMA engine on lan966x cannot > directly access host memory, so DMA buffers are allocated as contiguous > coherent memory and mapped through the PCIe Address Translation Unit > (ATU). The ATU provides outbound windows that translate internal FDMA > addresses to PCIe bus addresses, allowing the FDMA engine to read and > write host memory. Because the ATU requires contiguous address regions, > page_pool and normal per-page DMA mappings cannot be used. Instead, > frames are transferred using memcpy between the ATU-mapped buffers and > the network stack. With this, throughput increases from ~33 Mbps to > ~620 Mbps for default MTU. > I have applied the whole series and performed some tests. Issues observed in v1 are no more present. Tested-by: Herve Codina Best regards, Hervé