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Message-ID: <bee1807b7d072b221c44ac8c2ed8064939d33696.camel@gmail.com>
Subject: Re: [PATCH] ufs: core: Disable auto h8 before ssu
From:   Bean Huo <huobean@gmail.com>
To:     =?UTF-8?Q?=E9=AB=98=E4=B8=A5=E5=87=AF?= <gaoyankaigeren@gmail.com>,
        Avri Altman <Avri.Altman@wdc.com>
Cc:     Alim Akhtar <alim.akhtar@samsung.com>,
        Bart Van Assche <bvanassche@acm.org>,
        "James E . J . Bottomley" <jejb@linux.ibm.com>,
        Bean Huo <beanhuo@micron.com>,
        Adrian Hunter <adrian.hunter@intel.com>,
        "linux-scsi@vger.kernel.org" <linux-scsi@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Date:   Wed, 12 Oct 2022 16:25:17 +0200
In-Reply-To: <CAFN68yVajOkV++gCp-y1+SD5VOKLgUeBhfgskrJZOX5dfGi07A@mail.gmail.com>
References: <20221011021653.27277-1-gaoyankaigeren@gmail.com>
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         <CAFN68yVajOkV++gCp-y1+SD5VOKLgUeBhfgskrJZOX5dfGi07A@mail.gmail.com>
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On Tue, 2022-10-11 at 19:53 +0800, =E9=AB=98=E4=B8=A5=E5=87=AF wrote:
> Dear Avri
> =C2=A0 Unisoc reports resume fail on UFS(micron FS164) during
> suspend/resume test.
> =C2=A0 We check host inserts auto H8 enter/exit event between SSU sleep
> command and H8 enter command in runtime suspend .
> =C2=A0 Asfollows: SSU Sleep command --> auto H8 enter --> auto H8 exit --=
>
> H8 enter --> idle 2ms --> VCC off.
> =C2=A0 However device AQL FW can=E2=80=99t enter LPM within 2ms after sec=
ond H8
> enter command.
> =C2=A0 FW already enter LPM after receive auto H8 enter command , Next
> auto
> H8 exit command will trigger FW exit from LPM, it need take over
> 10ms,
> and FW can=E2=80=99t enter
> =C2=A0 LPM again after second H8 enter command until device complete exit
> from LPM. So disable auto h8 before ssu is a reasonable solution to
> solve it.
> =C2=A0 Hynix also has similar request.


Hi gaoyan,

The above sequence confuses me. UFSHCI has idle time before bringing
Link into hibern8 mode, do you know what the settings are?

Also, if auto-hibern8 is supported, in this case, the host-side SW
should not send manual hibern8. If this is an issue to all UFS or
UFSHCI, we should disable manual hibern8 if auto-hibern8 is enabled. or
let customer to choose one of two.


Kind regards,
Bean