Re: [PATCH] ufs: core: Disable auto h8 before ssu

[高严凯]

Dear Bean
we can choose one of two h8 for sure, and we chosed auto h8 during sys active.
when ufs suspend/resume, ufshcd_link_state_transtion will send DME h8
enter/exit always.
that's why the above sequence show up.
" UFSHCI has idle time before bringing Link into hibern8 mode, " I
think  ufs put the link to h8 during the time

Bean Huo <huobean@xxxxxxxxx> 于2022年10月12日周三 22:25写道：
>
> On Tue, 2022-10-11 at 19:53 +0800, 高严凯 wrote:
> > Dear Avri
> >   Unisoc reports resume fail on UFS(micron FS164) during
> > suspend/resume test.
> >   We check host inserts auto H8 enter/exit event between SSU sleep
> > command and H8 enter command in runtime suspend .
> >   Asfollows: SSU Sleep command --> auto H8 enter --> auto H8 exit -->
> > H8 enter --> idle 2ms --> VCC off.
> >   However device AQL FW can’t enter LPM within 2ms after second H8
> > enter command.
> >   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’t enter
> >   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.
> >   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