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=-2.1 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 C9255C433E0 for ; Thu, 21 May 2020 17:37:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA4A6207F7 for ; Thu, 21 May 2020 17:37:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=mg.codeaurora.org header.i=@mg.codeaurora.org header.b="oeUOIdLB" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727883AbgEURhQ (ORCPT ); Thu, 21 May 2020 13:37:16 -0400 Received: from mail26.static.mailgun.info ([104.130.122.26]:44346 "EHLO mail26.static.mailgun.info" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728761AbgEURhP (ORCPT ); Thu, 21 May 2020 13:37:15 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1590082635; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=F30tIyEfBVh5g5gaTce6ZjrM4vzM0/dihF/CEEqfqwE=; b=oeUOIdLBpIQvnK9WqzYt2m9Y4HvESSykxrdn6G7+wUwO0pXiVZZl/hJ3VX9rTA/v/XOFChWD rE1zwvrZElDdW/Y29jHTf2Xnq2UncOdRnWUfQFkVJvDicRiP2vR2V9B122VOra+yjlqzErPQ Hbn0P27j+h/RZnxKNCTgU0ks2c0= X-Mailgun-Sending-Ip: 104.130.122.26 X-Mailgun-Sid: WyI1MzIzYiIsICJsaW51eC1hcm0tbXNtQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n05.prod.us-west-2.postgun.com with SMTP id 5ec6bc497c3c9cd06989ea65 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Thu, 21 May 2020 17:37:13 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 3E976C433CB; Thu, 21 May 2020 17:37:13 +0000 (UTC) Received: from [10.110.95.251] (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: wcheng) by smtp.codeaurora.org (Postfix) with ESMTPSA id E707DC433C6; Thu, 21 May 2020 17:37:11 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org E707DC433C6 Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; dmarc=none (p=none dis=none) header.from=codeaurora.org Authentication-Results: aws-us-west-2-caf-mail-1.web.codeaurora.org; spf=none smtp.mailfrom=wcheng@codeaurora.org Subject: Re: [PATCH v2 0/3] Re-introduce TX FIFO resize for larger EP bursting To: agross@kernel.org, bjorn.andersson@linaro.org, robh+dt@kernel.org, balbi@kernel.org, gregkh@linuxfoundation.org Cc: linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, jackp@codeaurora.org References: <1590050169-30747-1-git-send-email-wcheng@codeaurora.org> From: Wesley Cheng Message-ID: <1e2e9c1b-fcd9-9e03-da86-a46e541a1480@codeaurora.org> Date: Thu, 21 May 2020 10:37:10 -0700 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <1590050169-30747-1-git-send-email-wcheng@codeaurora.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 5/21/2020 1:36 AM, Wesley Cheng wrote: > Changes in V2: > - Modified TXFIFO resizing logic to ensure that each EP is reserved a > FIFO. > - Removed dev_dbg() prints and fixed typos from patches > - Added some more description on the dt-bindings commit message > > Reviewed-by: Felipe Balbi > Reviewed-by: Rob Herring > Sorry, please disregard the Reviewed-by tags in the patches. I added those mistakenly. > Currently, there is no functionality to allow for resizing the TXFIFOs, and > relying on the HW default setting for the TXFIFO depth. In most cases, the > HW default is probably sufficient, but for USB compositions that contain > multiple functions that require EP bursting, the default settings > might not be enough. Also to note, the current SW will assign an EP to a > function driver w/o checking to see if the TXFIFO size for that particular > EP is large enough. (this is a problem if there are multiple HW defined > values for the TXFIFO size) > > It is mentioned in the SNPS databook that a minimum of TX FIFO depth = 3 > is required for an EP that supports bursting. Otherwise, there may be > frequent occurences of bursts ending. For high bandwidth functions, > such as data tethering (protocols that support data aggregation), mass > storage, and media transfer protocol (over FFS), the bMaxBurst value can be > large, and a bigger TXFIFO depth may prove to be beneficial in terms of USB > throughput. (which can be associated to system access latency, etc...) It > allows for a more consistent burst of traffic, w/o any interruptions, as > data is readily available in the FIFO. > > With testing done using the mass storage function driver, the results show > that with a larger TXFIFO depth, the bandwidth increased significantly. > > Test Parameters: > - Platform: Qualcomm SM8150 > - bMaxBurst = 6 > - USB req size = 256kB > - Num of USB reqs = 16 > - USB Speed = Super-Speed > - Function Driver: Mass Storage (w/ ramdisk) > - Test Application: CrystalDiskMark > > Results: > > TXFIFO Depth = 3 max packets > > Test Case | Data Size | AVG tput (in MB/s) > ------------------------------------------- > Sequential|1 GB x | > Read |9 loops | 193.60 > | | 195.86 > | | 184.77 > | | 193.60 > ------------------------------------------- > > TXFIFO Depth = 6 max packets > > Test Case | Data Size | AVG tput (in MB/s) > ------------------------------------------- > Sequential|1 GB x | > Read |9 loops | 287.35 > | | 304.94 > | | 289.64 > | | 293.61 > ------------------------------------------- > > Wesley Cheng (3): > usb: dwc3: Resize TX FIFOs to meet EP bursting requirements > arm64: boot: dts: qcom: sm8150: Enable dynamic TX FIFO resize logic > dt-bindings: usb: dwc3: Add entry for tx-fifo-resize > > Documentation/devicetree/bindings/usb/dwc3.txt | 2 +- > arch/arm64/boot/dts/qcom/sm8150.dtsi | 1 + > drivers/usb/dwc3/core.c | 2 + > drivers/usb/dwc3/core.h | 8 ++ > drivers/usb/dwc3/ep0.c | 37 ++++++++- > drivers/usb/dwc3/gadget.c | 111 +++++++++++++++++++++++++ > 6 files changed, 159 insertions(+), 2 deletions(-) > -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project