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=-10.2 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_1 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 95DD8C433B4 for ; Mon, 3 May 2021 23:45:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6A78B611EE for ; Mon, 3 May 2021 23:45:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229603AbhECXqJ (ORCPT ); Mon, 3 May 2021 19:46:09 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:59396 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229594AbhECXqJ (ORCPT ); Mon, 3 May 2021 19:46:09 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1620085515; h=Content-Transfer-Encoding: Content-Type: In-Reply-To: MIME-Version: Date: Message-ID: From: References: Cc: To: Subject: Sender; bh=lU7hJpSw4xNqkbBNU53B86vvvEoKe/qzoLF4p+Az8e0=; b=TT1yXQjhGj026CBvPf0NuSyjdhSWYlBjdpoztCLbJOz7GIuqYYs+V4fGuH7oCOPrwZtY8IBG 22YkRYRTsgPh3KnTEUp2ZVevxP3D1mL0KgaZc5BxGEBkFFsX1XBn1wr1mtWdlWUYGu02WwqK nxP0AT9L9+q7Tdnnh4hLak4E+PM= 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-n02.prod.us-west-2.postgun.com with SMTP id 60908af89a9ff96d95c7f053 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 03 May 2021 23:44:56 GMT Sender: hemantk=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 8F7F2C433D3; Mon, 3 May 2021 23:44:56 +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 ADEB0C433D3; Mon, 3 May 2021 23:44:55 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org ADEB0C433D3 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] bus: mhi: core: Fix power down latency To: Loic Poulain , mani@kernel.org Cc: linux-arm-msm@vger.kernel.org, bbhatt@codeaurora.org References: <1620029090-8975-1-git-send-email-loic.poulain@linaro.org> From: Hemant Kumar Message-ID: <2b901961-b33d-1c63-8fde-c92e102aa48d@codeaurora.org> Date: Mon, 3 May 2021 16:44:55 -0700 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: <1620029090-8975-1-git-send-email-loic.poulain@linaro.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 5/3/21 1:04 AM, Loic Poulain wrote: > On graceful power-down/disable transition, when an MHI reset is > performed, the MHI device loses its context, including interrupt > configuration. However, the current implementation is waiting for > event(irq) driven state change to confirm reset has been completed, > which never happens, and causes reset timeout, leading to unexpected > high latency of the mhi_power_down procedure (up to 45 seconds). > > Fix that by moving to the recently introduced poll_reg_field method, > waiting for the reset bit to be cleared, in the same way as the > power_on procedure. > > Fixes: a6e2e3522f29 ("bus: mhi: core: Add support for PM state transitions") > Signed-off-by: Loic Poulain Reviewed-by: Hemant Kumar -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project