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Date:   Mon, 25 Nov 2019 07:39:05 +0000
From:   cang@codeaurora.org
To:     Avri Altman <Avri.Altman@wdc.com>
Cc:     asutoshd@codeaurora.org, nguyenb@codeaurora.org,
        rnayak@codeaurora.org, linux-scsi@vger.kernel.org,
        kernel-team@android.com, saravanak@google.com, salyzyn@google.com,
        Alim Akhtar <alim.akhtar@samsung.com>,
        Pedro Sousa <pedrom.sousa@synopsys.com>,
        "James E.J. Bottomley" <jejb@linux.ibm.com>,
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        Stanley Chu <stanley.chu@mediatek.com>,
        Bean Huo <beanhuo@micron.com>,
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        Thomas Gleixner <tglx@linutronix.de>,
        Allison Randal <allison@lohutok.net>,
        open list <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v4 4/5] scsi: ufs: Do not clear the DL layer timers
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On 2019-11-25 15:22, Avri Altman wrote:
>> >
>> > During power mode change, PACP_PWR_Req frame sends
>> PAPowerModeUserData
>> > parameters (and they are considered valid by device if Flags[4] -
>> > UserDataValid bit is set in the same frame).
>> > Currently we don't set these PAPowerModeUserData parameters and
>> > hardware always sets UserDataValid bit which would clear all the DL
>> > layer timeout values of the peer device after the power mode change.
>> >
>> > This change sets the PAPowerModeUserData[0..5] to UniPro specification
>> > recommended default values, in addition we are also setting the
>> > relevant
>> > DME_LOCAL_* timer attributes as required by UFS HCI specification.
>> >
>> > Signed-off-by: Can Guo <cang@codeaurora.org>
>> Reviewed-by Avri Altman <avri.altman@wdc.com>
> BTW, I noticed that you are only updating the TC0 registers.
> Why not setting the TC1 registers as well?
> 
> Thanks,
> Avri

Hi Avri,

In the HCI spec, it goes

Currently, UFS uses TC0 only. Therefore, setting the following values 
are not needed:
 DME_ Local_FC1ProtectionTimeOutVal
 DME_ Local_TC1ReplayTimeOutVal
 DME_ Local_ AFC1ReqTimeOutVal

Best Regards,
Can Guo.