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=-5.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 2217AC432C3 for ; Fri, 15 Nov 2019 06:01:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EB0052072D for ; Fri, 15 Nov 2019 06:01:25 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="NXZEDtxA"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="UzJJL6r6" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726717AbfKOGBZ (ORCPT ); Fri, 15 Nov 2019 01:01:25 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:60952 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725774AbfKOGBZ (ORCPT ); Fri, 15 Nov 2019 01:01:25 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id E18DF6119A; Fri, 15 Nov 2019 06:01:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573797684; bh=vFqY/oN8QIMlspIG1CEoNcPzEthWXbyMO9RsePuR1Vs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=NXZEDtxAdxIrSDBfVsZqb+wrHRVv790+W+JfcTvy6NHyvTERm2sge/0Q+AFoQpDS3 dJMFms7THRILhfM8O6mpPcNP6D/iC2sHxNX8qhiAfkD3+I/GL9HuDZUxF6G9j/Wndw EI5IdeYPXNf0npg4fNXcGDM3t7unOZjONZYlxZzU= Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 32416610DB; Fri, 15 Nov 2019 06:01:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1573797679; bh=vFqY/oN8QIMlspIG1CEoNcPzEthWXbyMO9RsePuR1Vs=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=UzJJL6r654PBc14brdISZ/DMcMmfSnHORMjEjBU28YpXdK+JpY9Yi3s2Q5bHUNakT qGlCA8ADeEpVzluPXQA2DlmAjutvfmT+wUmXmjHdAi7G6gW/uW4YBrucjkrWn1WUHf kJgIDKUeT5ZsWl6fRwRelMmGV+gTQMz9YsDhl2oo= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 15 Nov 2019 14:01:18 +0800 From: Can Guo To: Bart Van Assche Cc: "Bean Huo (beanhuo)" , "Martin K . Petersen" , "James E . J . Bottomley" , Avri Altman , Asutosh Das , stummala@codeaurora.org, Vignesh Raghavendra , linux-scsi@vger.kernel.org, Stanley Chu , Tomas Winkler Subject: Re: [EXT] Re: [PATCH v5 4/4] ufs: Simplify the clock scaling mechanism implementation In-Reply-To: References: <20191112173743.141503-1-bvanassche@acm.org> <20191112173743.141503-5-bvanassche@acm.org> <8acd9237-7414-5dce-5285-69ed3ce6f28c@acm.org> Message-ID: X-Sender: cang@codeaurora.org User-Agent: Roundcube Webmail/1.2.5 Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 2019-11-15 00:11, Bart Van Assche wrote: > On 11/13/19 8:03 AM, Bean Huo (beanhuo) wrote: >> I think, you are asking for comment from Can. As for me, attached >> patch is better. >> Removing ufshcd_wait_for_doorbell_clr(), instead of reading doorbell >> register, Now >> using block layer blk_mq_{un,}freeze_queue(), looks good. I tested >> your V5 patches, >> didn't find problem yet. >> >> Since my available platform doesn't support dynamic clk scaling, I >> think, now seems only >> Qcom UFS controllers support this feature. So we need Can Guo to >> finally confirm it. > > Hi Can, > > Do you agree with this patch series if patch 4 is replaced by the > patch attached to my previous e-mail? The entire (revised) series is > available at https://github.com/bvanassche/linux/tree/ufs-for-next. > > Thanks, > > Bart. Hi Bart, After ufshcd_clock_scaling_prepare() returns(no error), all request queues are frozen. If failure happens(say power mode change command fails) after this point and error handler kicks off, we need to send dev commands(in ufshcd_probe_hba()) to bring UFS back to functionality. However, as the hba->cmd_queue is frozen, dev commands cannot be sent, the error handler shall fail. Thanks, Can Guo.