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=-5.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, 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 58226C433E0 for ; Fri, 15 Jan 2021 19:03:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1EC5523A5E for ; Fri, 15 Jan 2021 19:03:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728324AbhAOTDS (ORCPT ); Fri, 15 Jan 2021 14:03:18 -0500 Received: from m43-15.mailgun.net ([69.72.43.15]:61105 "EHLO m43-15.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726809AbhAOTDS (ORCPT ); Fri, 15 Jan 2021 14:03:18 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1610737377; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=bQX+qrjQlTesxdVEvUU3xEoWA196VqapN+k/7ckimuA=; b=rcKJTRcdKIctG7z3WXS43YzoxKEih8y+KQ8tMrHPBn1K4906p3RFIiqbxSFF4YV9YVeL1sOb XT/W/2FGeZhE9gYsVVQ+j64xuhTDrEwfu2miAauy5+cHvBHcXbsb+QQIreiozeqbtZ9jbGD2 bAgaIqlVsphIxQOB30YMf2qV11E= X-Mailgun-Sending-Ip: 69.72.43.15 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-n10.prod.us-west-2.postgun.com with SMTP id 6001e6c63b6dceb132d6a2d8 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 15 Jan 2021 19:02:30 GMT Sender: hemantk=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id E8EA3C433CA; Fri, 15 Jan 2021 19:02:29 +0000 (UTC) Received: from [10.46.162.249] (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: hemantk) by smtp.codeaurora.org (Postfix) with ESMTPSA id 2E125C433C6; Fri, 15 Jan 2021 19:02:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 2E125C433C6 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=hemantk@codeaurora.org Subject: Re: [PATCH v2 3/3] bus: mhi: core: Process execution environment changes serially To: Bhaumik Bhatt , manivannan.sadhasivam@linaro.org Cc: linux-arm-msm@vger.kernel.org, carl.yin@quectel.com, naveen.kumar@quectel.com, jhugo@codeaurora.org, linux-kernel@vger.kernel.org, loic.poulain@linaro.org References: <1610651795-31287-1-git-send-email-bbhatt@codeaurora.org> <1610651795-31287-4-git-send-email-bbhatt@codeaurora.org> From: Hemant Kumar Message-ID: <02206c10-f44f-bf6a-91ce-3cff8e7d0ea8@codeaurora.org> Date: Fri, 15 Jan 2021 11:02:28 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: <1610651795-31287-4-git-send-email-bbhatt@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 1/14/21 11:16 AM, Bhaumik Bhatt wrote: > In current design, whenever the BHI interrupt is fired, the execution > environment is updated. This can cause race conditions and impede any > ongoing power up/down processing. For example, if a power down is in > progress and the host has updated the execution environment to a > local "disabled" state, any BHI interrupt firing later could replace > it with the value from the BHI EE register. Can we add what is the real issue observed when mhi_cntrl->ee changed in above scenario? Another example would be > that the device can enter mission mode while device creation for SBL > is still going on, leading to multiple attempts at opening the same > channel. Even for this scenario, can we add the real issue that was observed e.g. same device was attempting to get created twice and caused xyz issue? > > Ensure that EE changes are handled only from appropriate places and > occur one after another and handle only PBL or RDDM EE changes as > critical events directly from the interrupt handler. This also makes > sure that we use the correct execution environment to notify the > controller driver when the device resets to one of the PBL execution > environments. > [..] Thanks, Hemant -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project