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 Received: from smtp4.osuosl.org (smtp4.osuosl.org [140.211.166.137]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 3E32CE7717D for ; Fri, 13 Dec 2024 11:54:48 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id B410D405CC; Fri, 13 Dec 2024 11:54:47 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id SGmf6uI890Ui; Fri, 13 Dec 2024 11:54:46 +0000 (UTC) X-Comment: SPF check N/A for local connections - client-ip=140.211.166.142; helo=lists1.osuosl.org; envelope-from=intel-wired-lan-bounces@osuosl.org; receiver= DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org C0C214058F DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=osuosl.org; s=default; t=1734090886; bh=rShDgTnzwc3npC3FIcFY6EJeSBdg6xutvc0Jf56TKwA=; h=Date:From:To:References:In-Reply-To:Subject:List-Id: List-Unsubscribe:List-Archive:List-Post:List-Help:List-Subscribe: Cc:From; b=BFWY2XzJi+iOYVGUUsBL49K5w6pEQRMwd5vqBzMumgKHdninF5snSTFEbYL1wZNAL ajllLQ9TTeosU23n+9bvuoyJFbaztHuCWpqkIz7b1e9mIf1aY2vN9fcdznnCyfD0BS 6hXs1TY8K/KGt7PPtBicEsb1KGjp8g+fspnDATiBXpAFq2nBg1gXyGQQrN/oPCo55V cK2vqlzWeze8iuz7Ipp529jUg0I20x9sg5jxQxWBOrnAGkxosWhj6z3feGTFKa6ZNa uqb7sr4GMdIi9vMrUeTzn9kyCjepVkd+P8eGIxayI+9Uj23oGIVladDLc2AlxKRE7f 0f9GLGHgGImdg== Received: from lists1.osuosl.org (lists1.osuosl.org [140.211.166.142]) by smtp4.osuosl.org (Postfix) with ESMTP id C0C214058F; Fri, 13 Dec 2024 11:54:46 +0000 (UTC) Received: from smtp1.osuosl.org (smtp1.osuosl.org [140.211.166.138]) by lists1.osuosl.org (Postfix) with ESMTP id A9E1DECD for ; Fri, 13 Dec 2024 11:54:44 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp1.osuosl.org (Postfix) with ESMTP id 9206A8135D for ; Fri, 13 Dec 2024 11:54:44 +0000 (UTC) X-Virus-Scanned: amavis at osuosl.org Received: from smtp1.osuosl.org ([127.0.0.1]) by localhost (smtp1.osuosl.org [127.0.0.1]) (amavis, port 10024) with ESMTP id 7ogO3es1EiCh for ; Fri, 13 Dec 2024 11:54:44 +0000 (UTC) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=2604:1380:4641:c500::1; helo=dfw.source.kernel.org; envelope-from=horms@kernel.org; receiver= DMARC-Filter: OpenDMARC Filter v1.4.2 smtp1.osuosl.org EB85F8132B DKIM-Filter: OpenDKIM Filter v2.11.0 smtp1.osuosl.org EB85F8132B Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by smtp1.osuosl.org (Postfix) with ESMTPS id EB85F8132B for ; Fri, 13 Dec 2024 11:54:43 +0000 (UTC) Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id 6AF4E5C32DC; Fri, 13 Dec 2024 11:54:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id BE190C4CED0; Fri, 13 Dec 2024 11:54:40 +0000 (UTC) Date: Fri, 13 Dec 2024 11:54:38 +0000 From: Simon Horman To: Michal Schmidt Message-ID: <20241213115438.GP2110@kernel.org> References: <20241212153417.165919-1-mschmidt@redhat.com> <20241212153417.165919-3-mschmidt@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20241212153417.165919-3-mschmidt@redhat.com> X-Mailman-Original-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1734090882; bh=nEQGTQHmIQhO0/A9uStQC/R0spmJDZztIzVtIEjRsyk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ESq6JEwktjriu1cljx3tf9sSHX+DDhg+Qm0bpw3zow1aJBEt9S/PWnlnint+AwgJG q8EI0fw4oTVEGvLMGAkjP2H7LwmMALFLMolYlZGeuopTmtaypJCBNt8jM7eTuj56Ih Ufs+Y8krPM6aSK8wSiRBkGmIHZpRFDCZfSfUC4q26wHfm3t+UTpzdQPci3i0pVmESZ EdW4G6baxNiCi+smBSpGKfhrUFKuAMtk6HHwAvp9UsEtVal7xTWKeHiM/zUF2TLuP4 xJK9Ml6ZhO8pcA1YA3pBlWMTtrLuBDD1wmtjUiOxxmVIeQuJTw39JK7orudUwBHiwr QZcFzfEn5R34w== X-Mailman-Original-Authentication-Results: smtp1.osuosl.org; dmarc=pass (p=quarantine dis=none) header.from=kernel.org X-Mailman-Original-Authentication-Results: smtp1.osuosl.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=ESq6JEwk Subject: Re: [Intel-wired-lan] [PATCH iwl-next 2/3] ice: lower the latency of GNSS reads X-BeenThere: intel-wired-lan@osuosl.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Intel Wired Ethernet Linux Kernel Driver Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: netdev@vger.kernel.org, Arkadiusz Kubalewski , Karol Kolacinski , Tony Nguyen , Przemek Kitszel , intel-wired-lan@lists.osuosl.org Errors-To: intel-wired-lan-bounces@osuosl.org Sender: "Intel-wired-lan" On Thu, Dec 12, 2024 at 04:34:16PM +0100, Michal Schmidt wrote: > The E810 is connected to the u-blox GNSS module over I2C. The ice driver > periodically (every ~20ms) sends AdminQ commands to poll the u-blox for > available data. Most of the time, there's no data. When the u-blox > finally responds that data is available, usually it's around 800 bytes. > It can be more or less, depending on how many NMEA messages were > configured using ubxtool. ice then proceeds to read all the data. > AdminQ and I2C are slow. The reading is performed in chunks of 15 bytes. > ice reads all of the data before passing it to the kernel GNSS subsystem > and onwards to userspace. > > Improve the NMEA message receiving latency. Pass each 15-bytes chunk to > userspace as soon as it's received. > > Tested-by: Miroslav Lichvar > Signed-off-by: Michal Schmidt Reviewed-by: Simon Horman