From patchwork Fri Jan 29 04:46:39 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Wesley Cheng X-Patchwork-Id: 12055133 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=-11.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 D7DE1C433E6 for ; Fri, 29 Jan 2021 04:48:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADE2064DFF for ; Fri, 29 Jan 2021 04:48:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231788AbhA2EsY (ORCPT ); Thu, 28 Jan 2021 23:48:24 -0500 Received: from a1.mail.mailgun.net ([198.61.254.60]:38224 "EHLO a1.mail.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231820AbhA2Ert (ORCPT ); Thu, 28 Jan 2021 23:47:49 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1611895650; h=Message-Id: Date: Subject: Cc: To: From: Sender; bh=EU5RjXRxYWSaZvF77fs2S7MnownYSfzA+7vesuYPTwo=; b=aAtOdEzA3N0aLbbdL8TJ+MDGwaR7AaXiWhgib0cYWL1qpOLopnbtxgSg9o4+otjmY4GVuH7j CwKk5BmD4jzlaDwVwFi36GB6w14ktCEYOa7S2RPlWzmhbdAL5pk4a5cHYL4SjCk9Gq0BtNY2 LVBjD8Lp+cczv4jqcxXoMzCC2Qs= X-Mailgun-Sending-Ip: 198.61.254.60 X-Mailgun-Sid: WyIxZTE2YSIsICJsaW51eC11c2JAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n02.prod.us-west-2.postgun.com with SMTP id 6013933b91b605c2ed01bcc2 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 29 Jan 2021 04:46:51 GMT Sender: wcheng=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 40111C43461; Fri, 29 Jan 2021 04:46:51 +0000 (UTC) Received: from wcheng-linux.qualcomm.com (i-global254.qualcomm.com [199.106.103.254]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) (Authenticated sender: wcheng) by smtp.codeaurora.org (Postfix) with ESMTPSA id D9426C433C6; Fri, 29 Jan 2021 04:46:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org D9426C433C6 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=fail smtp.mailfrom=wcheng@codeaurora.org From: Wesley Cheng To: agross@kernel.org, bjorn.andersson@linaro.org, balbi@kernel.org, gregkh@linuxfoundation.org, robh+dt@kernel.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org, Wesley Cheng Subject: [PATCH v7 0/5] Re-introduce TX FIFO resize for larger EP bursting Date: Thu, 28 Jan 2021 20:46:39 -0800 Message-Id: <1611895604-4496-1-git-send-email-wcheng@codeaurora.org> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Changes in V7: - Added a new property tx-fifo-max-num for limiting how much fifo space the resizing logic can allocate for endpoints with large burst values. This can differ across platforms, and tie in closely with overall system latency. - Added recommended checks for DWC32. - Added changes to set the tx-fifo-resize property from dwc3-qcom by default instead of modifying the current DTSI files. - Added comments on all APIs/variables introduced. - Updated the DWC3 YAML to include a better description of the tx-fifo-resize property and added an entry for tx-fifo-max-num. Changes in V6: - Rebased patches to usb-testing. - Renamed to PATCH series instead of RFC. - Checking for fs_descriptors instead of ss_descriptors for determining the endpoint count for a particular configuration. - Re-ordered patch series to fix patch dependencies. Changes in V5: - Added check_config() logic, which is used to communicate the number of EPs used in a particular configuration. Based on this, the DWC3 gadget driver has the ability to know the maximum number of eps utilized in all configs. This helps reduce unnecessary allocation to unused eps, and will catch fifo allocation issues at bind() time. - Fixed variable declaration to single line per variable, and reverse xmas. - Created a helper for fifo clearing, which is used by ep0.c Changes in V4: - Removed struct dwc3* as an argument for dwc3_gadget_resize_tx_fifos() - Removed WARN_ON(1) in case we run out of fifo space Changes in V3: - Removed "Reviewed-by" tags - Renamed series back to RFC - Modified logic to ensure that fifo_size is reset if we pass the minimum threshold. Tested with binding multiple FDs requesting 6 FIFOs. 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 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 (5): usb: gadget: udc: core: Introduce check_config to verify USB configuration usb: gadget: configfs: Check USB configuration before adding usb: dwc3: Resize TX FIFOs to meet EP bursting requirements usb: dwc3: dwc3-qcom: Enable tx-fifo-resize property by default dt-bindings: usb: dwc3: Update dwc3 TX fifo properties .../devicetree/bindings/usb/snps,dwc3.yaml | 15 +- drivers/usb/dwc3/core.c | 9 + drivers/usb/dwc3/core.h | 15 ++ drivers/usb/dwc3/dwc3-qcom.c | 10 + drivers/usb/dwc3/ep0.c | 2 + drivers/usb/dwc3/gadget.c | 214 +++++++++++++++++++++ drivers/usb/gadget/configfs.c | 22 +++ drivers/usb/gadget/udc/core.c | 25 +++ include/linux/usb/gadget.h | 5 + 9 files changed, 315 insertions(+), 2 deletions(-)