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=-3.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 27B54C433E1 for ; Tue, 30 Mar 2021 12:49:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 01965619B1 for ; Tue, 30 Mar 2021 12:49:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232086AbhC3MtJ (ORCPT ); Tue, 30 Mar 2021 08:49:09 -0400 Received: from so254-9.mailgun.net ([198.61.254.9]:42369 "EHLO so254-9.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232005AbhC3MtH (ORCPT ); Tue, 30 Mar 2021 08:49:07 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1617108546; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=96qHzHGoEEUmPTxHIx4FwcAj71je9EFrRv4IZ94Y4BU=; b=dRWRUsG1jkFq8rfV0zOrJ+4/jFc3pXQBzT5k2LVdxv8h/roOUDM6R+eoCHAr5xutgb80DOWp l13nkNH0SOUGx5NtThld+cI5Mt2JC2+Kpu5xod/Vri9pW1gwny9U0qdX2sbXpFvyN0gDsXM4 M+k8pNI2lJ0hLYw4u8YEy12P7OY= X-Mailgun-Sending-Ip: 198.61.254.9 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-n02.prod.us-east-1.postgun.com with SMTP id 60631e2c0a4a07ffdade47fe (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Tue, 30 Mar 2021 12:48:44 GMT Sender: saiprakash.ranjan=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 4C1F7C43461; Tue, 30 Mar 2021 12:48:44 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: saiprakash.ranjan) by smtp.codeaurora.org (Postfix) with ESMTPSA id E52CDC433C6; Tue, 30 Mar 2021 12:48:43 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Tue, 30 Mar 2021 18:18:43 +0530 From: Sai Prakash Ranjan To: Greg Kroah-Hartman Cc: Sandeep Maheswaram , Felipe Balbi , Stephen Boyd , Doug Anderson , Matthias Kaehlcke , linux-arm-msm@vger.kernel.org, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Manu Gautam Subject: Re: [PATCH v1] usb: dwc3: core: Add shutdown callback for dwc3 In-Reply-To: References: <1616527652-7937-1-git-send-email-sanm@codeaurora.org> Message-ID: X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 2021-03-30 16:46, Greg Kroah-Hartman wrote: > On Tue, Mar 30, 2021 at 03:25:58PM +0530, Sai Prakash Ranjan wrote: >> On 2021-03-30 14:37, Greg Kroah-Hartman wrote: >> > On Tue, Mar 30, 2021 at 02:12:04PM +0530, Sandeep Maheswaram wrote: >> > > >> > > On 3/26/2021 7:07 PM, Greg Kroah-Hartman wrote: >> > > > On Wed, Mar 24, 2021 at 12:57:32AM +0530, Sandeep Maheswaram wrote: >> > > > > This patch adds a shutdown callback to USB DWC core driver to ensure that >> > > > > it is properly shutdown in reboot/shutdown path. This is required >> > > > > where SMMU address translation is enabled like on SC7180 >> > > > > SoC and few others. If the hardware is still accessing memory after >> > > > > SMMU translation is disabled as part of SMMU shutdown callback in >> > > > > system reboot or shutdown path, then IOVAs(I/O virtual address) >> > > > > which it was using will go on the bus as the physical addresses which >> > > > > might result in unknown crashes (NoC/interconnect errors). >> > > > > >> > > > > Previously this was added in dwc3 qcom glue driver. >> > > > > https://patchwork.kernel.org/project/linux-arm-msm/list/?series=382449 >> > > > > But observed kernel panic as glue driver shutdown getting called after >> > > > > iommu shutdown. As we are adding iommu nodes in dwc core node >> > > > > in device tree adding shutdown callback in core driver seems correct. >> > > > So shouldn't you also remove this from the qcom glue driver at the same >> > > > time? Please submit both as a patch series. >> > > > >> > > > thanks, >> > > > >> > > > greg k-h >> > > >> > > Hi Greg, >> > > >> > > The qcom glue driver patch is not merged yet. I have just mentioned >> > > for it for reference. >> > >> > You know that we can not add callbacks for no in-kernel user, so what >> > good is this patch for now? >> > >> >> What in-kernel user? Since when does shutdown callback need an >> in-kernel >> user? When you reboot or shutdown a system, it gets called. The reason >> why the shutdown callback is needed is provided in the commit text. > > As I can't see the patch here, I have no idea... You are replying now to the same patch which adds this shutdown callback :) Anyways the qcom dwc3 driver patch which is abandoned which is also mentioned in the commit text is here [1] and the new shutdown callback patch which we are both replying to is in here [2] [1] https://lore.kernel.org/lkml/1605162619-10064-1-git-send-email-sanm@codeaurora.org/ [2] https://lore.kernel.org/lkml/1616527652-7937-1-git-send-email-sanm@codeaurora.org/ Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation