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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 750C7C4332F for ; Thu, 9 Nov 2023 04:15:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232301AbjKIEIE (ORCPT ); Wed, 8 Nov 2023 23:08:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49570 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229923AbjKIEIA (ORCPT ); Wed, 8 Nov 2023 23:08:00 -0500 Received: from mx0a-0031df01.pphosted.com (mx0a-0031df01.pphosted.com [205.220.168.131]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4415BE8; Wed, 8 Nov 2023 20:07:58 -0800 (PST) Received: from pps.filterd (m0279862.ppops.net [127.0.0.1]) by mx0a-0031df01.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 3A93U6nG026770; Thu, 9 Nov 2023 04:07:44 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=quicinc.com; h=message-id : date : mime-version : subject : to : cc : references : from : in-reply-to : content-type : content-transfer-encoding; s=qcppdkim1; bh=gPcOCX+RaeBYyDl5KmgqK3Sy160qLKgKk2zgbBb3hmw=; b=fttf5sGdpVIH3jljgCyvipGZeaWvAFx8dRk+oYPbkcIhdy67t7ttDD3RoSLswb84sQAl y8uyUWQ90DWe8am3ogUoass4G3yQfuVK04cEmzBK33/nTx8nz7/gw1t6eODxEpUGUHsm ZM32gSL+XDwatN3Z4tzbcRU1AEue8uC/sLbapGPbnxcCFOCbrikPehvv/ov1DTtT0jda iUFSIKpSDaOSto6xBZSVqqt/v0Hwh/3ASdVnICiObMUGOkUG/GYaSJzZhUHGEe4tiqwv /jGED8tesqDjELhxupzPKUPK/RaJoMGfAgAOWeKw8oEAfQ8AI8dfksxUEqYUf51EGP1y Mg== Received: from nalasppmta02.qualcomm.com (Global_NAT1.qualcomm.com [129.46.96.20]) by mx0a-0031df01.pphosted.com (PPS) with ESMTPS id 3u7w2ebj5c-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 09 Nov 2023 04:07:44 +0000 Received: from nalasex01a.na.qualcomm.com (nalasex01a.na.qualcomm.com [10.47.209.196]) by NALASPPMTA02.qualcomm.com (8.17.1.5/8.17.1.5) with ESMTPS id 3A947hoR008863 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 9 Nov 2023 04:07:43 GMT Received: from [10.253.32.19] (10.80.80.8) by nalasex01a.na.qualcomm.com (10.47.209.196) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1118.39; Wed, 8 Nov 2023 20:07:39 -0800 Message-ID: <91ff9299-9a2a-94b5-c9a7-c5599292cb2b@quicinc.com> Date: Thu, 9 Nov 2023 12:07:37 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:102.0) Gecko/20100101 Thunderbird/102.15.1 Subject: Re: [PATCH v2 3/7] scsi: ufs: ufs-qcom: Allow the first init start with the maximum supported gear To: Manivannan Sadhasivam CC: Can Guo , , , , , , , , , Andy Gross , Bjorn Andersson , Konrad Dybcio , "James E.J. Bottomley" , "open list:ARM/QUALCOMM SUPPORT" , open list References: <1699332374-9324-1-git-send-email-cang@qti.qualcomm.com> <1699332374-9324-4-git-send-email-cang@qti.qualcomm.com> <20231108052310.GC3296@thinkpad> <49b331dc-37eb-6e26-f701-c83187a30788@quicinc.com> <20231109034717.GD3752@thinkpad> Content-Language: en-US From: Can Guo In-Reply-To: <20231109034717.GD3752@thinkpad> Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.80.80.8] X-ClientProxiedBy: nasanex01a.na.qualcomm.com (10.52.223.231) To nalasex01a.na.qualcomm.com (10.47.209.196) X-QCInternal: smtphost X-Proofpoint-Virus-Version: vendor=nai engine=6200 definitions=5800 signatures=585085 X-Proofpoint-ORIG-GUID: qIy1BpIXQMrtzmJdpR7-VY3DFwVOb0sQ X-Proofpoint-GUID: qIy1BpIXQMrtzmJdpR7-VY3DFwVOb0sQ X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.272,Aquarius:18.0.987,Hydra:6.0.619,FMLib:17.11.176.26 definitions=2023-11-09_02,2023-11-08_01,2023-05-22_02 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 mlxscore=0 phishscore=0 mlxlogscore=999 adultscore=0 clxscore=1015 lowpriorityscore=0 impostorscore=0 suspectscore=0 priorityscore=1501 spamscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2311060000 definitions=main-2311090032 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Mani, On 11/9/2023 11:47 AM, Manivannan Sadhasivam wrote: > On Wed, Nov 08, 2023 at 04:21:52PM +0800, Can Guo wrote: >> Hi Mani, >> >> On 11/8/2023 1:23 PM, Manivannan Sadhasivam wrote: >>> On Mon, Nov 06, 2023 at 08:46:09PM -0800, Can Guo wrote: >>>> From: Can Guo >>>> >>>> During host driver init, the phy_gear is set to the minimum supported gear >>>> (HS_G2). Then, during the first power mode change, the negotiated gear, say >>>> HS-G4, is updated to the phy_gear variable so that in the second init the >>>> updated phy_gear can be used to program the PHY. >>>> >>>> But the current code only allows update the phy_gear to a higher value. If >>>> one wants to start the first init with the maximum support gear, say HS-G4, >>>> the phy_gear is not updated to HS-G3 if the device only supports HS-G3. >>>> >>> >>> Can you elaborate when this can happen? AFAICS, there are 3 possibilities of >>> initial phy gear with this series: >>> >>> 1. If ufshc is < 5.0, then G2 will be used. >>> 2. If ufshc is >= 5.0 and if the version is populated in register, then that >>> gear will be used. Most likely that gear can be G4/G5 depending on the device >>> connected. >>> 3. If ufshc is >=5.0 and version is not populated, then G4 will be used. >>> >>> In all the above cases, I do not see any necessity to switch the phy gear >>> setting to lower one while scaling. Since the gears are backwards compatible, >>> we always use one phy gear sequence. Moreover, we only have 2 init sequences. >>> >>> Please correct me if I'm missing anything. >>> >>> - Mani >> In the next patch, I am setting the initial PHY gear to max HS gear read >> from UFS host cap register, so that we don't need to keep updating the >> initial value for host->phy_gear for different HW versions in future. FYI, >> for HW ver 5 and 6, it is HS-G5. In future, the max gear might become HS-G6 >> or higher on newer HW verions. >> >> I the case #3, if HS-G5 is set to host->phy_gear, the first init uses HS-G5, >> then after negotiation if the agreed gear is HS-G4, we need to update >> host->phy_gear to HS-G4 (a lower value) such that we use a power saving PHY >> gear settings during the 2nd init. >> >> If the commit message is making you confused, I can update it in next >> version. Please let me if I made any mistakes here. >> > > I see redundancy while setting the phy_gear and it is leading to confusion. > In ufs_qcom_set_host_params(), first you are setting phy_gear based on > ufs_qcom_get_hs_gear(), then changing it again with the version check for v5. > > I don't see a necessity for "host->phy_gear = host_params->hs_tx_gear", since in > the later check, you are covering both version <5 and >=5. In the case of HW version >= 5, we are only overwriting the PHY gear only if the UFS device cannot support HS-G5. Hence, we need to give host->phy_gear an initial value. > > Btw, it would be better to move this logic to a separate function like > ufs_qcom_get_phy_gear() to align with ufs_qcom_get_hs_gear(). > OK, will do in next version. Thanks, Can Guo. > - Mani > >> Thanks, >> Can Guo. >