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From:   Alim Akhtar <alim.akhtar@gmail.com>
Date:   Wed, 17 Jun 2020 14:27:19 +0530
Message-ID: <CAGOxZ50TUnvmmdspxr6dHWrpoxZqHtvR-1Wg6jAVH6k-w5LT2w@mail.gmail.com>
Subject: Re: [RFC PATCH v2 2/5] scsi: ufs: Add UFS-feature layer
To:     Avri Altman <Avri.Altman@wdc.com>
Cc:     "daejun7.park@samsung.com" <daejun7.park@samsung.com>,
        Bean Huo <huobean@gmail.com>,
        ALIM AKHTAR <alim.akhtar@samsung.com>,
        "jejb@linux.ibm.com" <jejb@linux.ibm.com>,
        "martin.petersen@oracle.com" <martin.petersen@oracle.com>,
        "asutoshd@codeaurora.org" <asutoshd@codeaurora.org>,
        "beanhuo@micron.com" <beanhuo@micron.com>,
        "stanley.chu@mediatek.com" <stanley.chu@mediatek.com>,
        "cang@codeaurora.org" <cang@codeaurora.org>,
        "bvanassche@acm.org" <bvanassche@acm.org>,
        "tomas.winkler@intel.com" <tomas.winkler@intel.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Sang-yoon Oh <sangyoon.oh@samsung.com>,
        Sung-Jun Park <sungjun07.park@samsung.com>,
        yongmyung lee <ymhungry.lee@samsung.com>,
        Jinyoung CHOI <j-young.choi@samsung.com>,
        Adel Choi <adel.choi@samsung.com>,
        BoRam Shin <boram.shin@samsung.com>
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On Wed, Jun 17, 2020 at 12:27 PM Avri Altman <Avri.Altman@wdc.com> wrote:
>
> >
> > Hi, Bean
> > >
> > > On Mon, 2020-06-15 at 16:23 +0900, Daejun Park wrote:
> > > > +void ufsf_scan_features(struct ufs_hba *hba)
> > > > +{
> > > > +       int ret;
> > > > +
> > > > +       init_waitqueue_head(&hba->ufsf.sdev_wait);
> > > > +       atomic_set(&hba->ufsf.slave_conf_cnt, 0);
> > > > +
> > > > +       if (hba->dev_info.wspecversion >= HPB_SUPPORTED_VERSION &&
> > > > +           (hba->dev_info.b_ufs_feature_sup & UFS_DEV_HPB_SUPPORT))
> > >
> > > How about removing this check "(hba->dev_info.wspecversion >=
> > > HPB_SUPPORTED_VERSION" since ufs with lower version than v3.1 can add
> > > HPB feature by FFU,
> > > if (hba->dev_info.b_ufs_feature_sup  &UFS_FEATURE_SUPPORT_HPB_BIT) is
> > > enough.
> > OK, changing it seems no problem. But I want to know what other people
> > think
> > about this version checking code.
> HPB1.0 isn't part of ufs3.1, but published only later.
> Allowing earlier versions will required to quirk the descriptor sizes.
> I see Bean's point here, but I vote for adding it in a single quirk, when the time comes.
>
I second Avri here, older devices need a quirk to handle, let do that
as a separate patch.
> Thanks,
> Avri


-- 
Regards,
Alim