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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_NEOMUTT autolearn=unavailable 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 C2350C04AB1 for ; Mon, 13 May 2019 09:59:39 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 96F5920989 for ; Mon, 13 May 2019 09:59:39 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="jqV6Pfk8" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 96F5920989 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bootlin.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=5u+6U9m5rWCTepEUIZt7ePaDCcLp639SbJnEUEdlIR4=; b=jqV6Pfk8vIIArs WrlhAOrzJtpK1bSmyDNWBlyUxEpMjmrCCTI0BcGsko7UAglCRyE6GtGMGT8vLjCTaTD6MTQ004YOj 3FbGAV7yvlpRmEvyj8YNve253Bkoev29fZxCDL5LAoGU9awFV7AzHxGK1FFeSGN0UCfIwluLNceyu N4NakyJKEZhWiyW2uiqUbXjh7MA8aGAE+vDzkDGZs8OuGlB1ItyTs39CkhAzSuco3re4jEj835JQH gLktNJP1p87tkRnJuvKTwO73QKjj9TRV/MhCVwJd4XAWoBchcWh5grLxd0E5vNZL2xb4ZH2DiqHDB DtFQfrN3FY7cKq+r5ZwQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hQ7k8-0005kE-FN; Mon, 13 May 2019 09:59:36 +0000 Received: from relay12.mail.gandi.net ([217.70.178.232]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hQ7k5-0005js-4T for linux-arm-kernel@lists.infradead.org; Mon, 13 May 2019 09:59:34 +0000 Received: from localhost (unknown [80.215.106.0]) (Authenticated sender: maxime.ripard@bootlin.com) by relay12.mail.gandi.net (Postfix) with ESMTPSA id 5012F200006; Mon, 13 May 2019 09:59:16 +0000 (UTC) Date: Mon, 13 May 2019 11:59:16 +0200 From: Maxime Ripard To: Uenal Mutlu Subject: Re: [RFC PATCH v2 RESEND] drivers: ata: ahci_sunxi: Increased SATA/AHCI DMA TX/RX FIFOs Message-ID: <20190513095916.yyjdtueeefkf4v4b@flea> References: <20190512205954.18435-1-um@mutluit.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20190512205954.18435-1-um@mutluit.com> User-Agent: NeoMutt/20180716 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190513_025933_327941_35AB2EB5 X-CRM114-Status: GOOD ( 16.55 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Jens Axboe , Mark Rutland , Hans de Goede , Oliver Schinagl , Andre Przywara , Linus Walleij , linux-sunxi@googlegroups.com, FUKAUMI Naoki , linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org, Chen-Yu Tsai , Jagan Teki , Pablo Greco , linux-amarula@amarulasolutions.com, linux-arm-kernel@lists.infradead.org, Stefan Monnier Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi, On Sun, May 12, 2019 at 10:59:54PM +0200, Uenal Mutlu wrote: > Increasing the SATA/AHCI DMA TX/RX FIFOs (P0DMACR.TXTS and .RXTS, ie. > TX_TRANSACTION_SIZE and RX_TRANSACTION_SIZE) from default 0x0 each > to 0x3 each, gives a write performance boost of 120 MiB/s to 132 MiB/s > from lame 36 MiB/s to 45 MiB/s previously. > Read performance is about 200 MiB/s. > [tested on SSD using dd bs=2K/4K/8K/12K/16K/24K/32K: peak-perf at 12K]. > > Tested on the Banana Pi R1 (aka Lamobo R1) and Banana Pi M1 SBCs > with Allwinner A20 32bit-SoCs (ARMv7-a / arm-linux-gnueabihf). > These devices are RaspberryPi-like small devices. > > This problem of slow SATA write-speed with these small devices lasts now > for more than 5 years. Many commentators throughout the years wrongly > assumed the slow write speed was a hardware limitation. This patch finally > solves the problem, which in fact was just a hard-to-fix software problem > (b/c of lack of documentation by the SoC-maker Allwinner Technology). > > RFC: Since more than about 25 similar SBC/SoC models do use the > ahci_sunxi driver, users are encouraged to test it on all the > affected boards and give feedback. > > Lists of the affected sunxi and other boards and SoCs with SATA using > the ahci_sunxi driver: > $ grep -i -e "^&ahci" arch/arm/boot/dts/sun*dts > and http://linux-sunxi.org/SATA#Devices_with_SATA_ports > See also http://linux-sunxi.org/Category:Devices_with_SATA_port > > Patch v2: > - Commented the patch in-place in ahci_sunxi.c > - With bs=12K and no conv=... passed to dd, the write performance > rises further to 132 MiB/s > - Changed MB/s to MiB/s > - Posted the story behind the patch: > http://lkml.iu.edu/hypermail/linux/kernel/1905.1/03506.html > - Posted a dd test script to find optimal bs, and some results: > https://bit.ly/2YoOzEM > > Patch v1: > - States bs=4K for dd and a write performance of 120 MiB/s > > Signed-off-by: Uenal Mutlu Acked-by: Maxime Ripard Just a minor nitpick though, the part starting with RFC: and with the version changelog should be after the --- below so that it doesn't get applied as part of the commit log. Maxime -- Maxime Ripard, Bootlin Embedded Linux and Kernel engineering https://bootlin.com _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel