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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, 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 16027C433E2 for ; Wed, 3 Jun 2020 12:26:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EC1EE20825 for ; Wed, 3 Jun 2020 12:26:25 +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="C0ILPLNJ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725833AbgFCM0Z (ORCPT ); Wed, 3 Jun 2020 08:26:25 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:18090 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725943AbgFCM0Y (ORCPT ); Wed, 3 Jun 2020 08:26:24 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1591187183; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=KfYEbXwoX+aABDlZlOKRx/sTdh4324Te4XRf5exbMGw=; b=C0ILPLNJhSvX+1hvAyySJzBtX2yYUU5e0MIePEEYvecD/UFNXZcN8iVmLAW5pE8ax2i2SC9o iER7e3aWU0WMl/3N8H/6ikD84BNZB0j0D/S0Xk2J/v0+KP3OjvQB8sgnCibe/7QwtP3QC78P 28lXjNwuLP6AMM0O3eM8odzxh4Q= X-Mailgun-Sending-Ip: 69.72.43.7 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-n03.prod.us-west-2.postgun.com with SMTP id 5ed796ee46d39fc0a2106c20 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Wed, 03 Jun 2020 12:26:22 GMT Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 46C69C43391; Wed, 3 Jun 2020 12:26:22 +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 BD91BC433C6; Wed, 3 Jun 2020 12:26:21 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Wed, 03 Jun 2020 17:56:21 +0530 From: Sai Prakash Ranjan To: Robin Murphy Cc: Mathieu Poirier , Suzuki K Poulose , Mike Leach , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, coresight@lists.linaro.org, Stephen Boyd Subject: Re: [PATCH 2/2] coresight: tmc: Add shutdown callback for TMC ETR/ETF In-Reply-To: <6c1a4fbd-98cb-a49c-0ced-1318d5d5e7c8@arm.com> References: <28123d1e19f235f97555ee36a5ed8b52d20cbdea.1590947174.git.saiprakash.ranjan@codeaurora.org> <20200601212858.GB24287@xps15> <1549935cf69ac3a006f32eb278821027@codeaurora.org> <6c1a4fbd-98cb-a49c-0ced-1318d5d5e7c8@arm.com> Message-ID: <7fe5762b5cb8f87e988232922d06c55d@codeaurora.org> X-Sender: saiprakash.ranjan@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org Hi Robin, On 2020-06-03 17:51, Robin Murphy wrote: > On 2020-06-03 13:00, Sai Prakash Ranjan wrote: >> Hi Robin, Mathieu >> >> On 2020-06-03 17:07, Robin Murphy wrote: >>> On 2020-06-01 22:28, Mathieu Poirier wrote: >>>> That being said I'm sure that dependencies on an IOMMU isn't a >>>> problem confined >>>> to coresight. I am adding Robin Murphy, who added this commit [1], >>>> to the thread >>>> in the hope that he can provide guidance on the right way to do >>>> this. >>> >>> Right, it's not specific to CoreSight, and it's not even specific to >>> IOMMUs really. In short, blame kexec ;) >>> >> >> Yes it is not specific to coresight, we are targeting this for all >> consumers/clients of SMMU(atleast on SC7180 SoC). We have display >> throwing >> NoC/interconnect errors[1] during reboot after SMMU is disabled. >> This is also not specific to kexec either as you explained here [2] >> about >> a case with display which is exacly what is happening in our system >> [1]. > > Sure, but those instances are begging the question of why the SMMU is > disabled at reboot in the first place ;) > That is what happens in SMMU shutdown callback right? It is the reboot/shutdown flow. arm_smmu_device_shutdown() platform_drv_shutdown() device_shutdown() kernel_restart_prepare() kernel_restart() Thanks, Sai -- QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation