From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
Subject: Re: [PATCH] drm/psr: Fix missed entry in PSR setup time table.
Date: Fri, 11 May 2018 12:46:45 -0700
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To: "Souza, Jose" <jose.souza@intel.com>, "intel-gfx@lists.freedesktop.org" <intel-gfx@lists.freedesktop.org>
Cc: "ville.syrjala@linux.intel.com" <ville.syrjala@linux.intel.com>, "stable@vger.kernel.org" <stable@vger.kernel.org>, DRI Development <dri-devel@lists.freedesktop.org>
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On Fri, 2018-05-11 at 18:03 +0000, Souza, Jose wrote:
> On Thu, 2018-05-10 at 17:54 -0700, Dhinakaran Pandiyan wrote:
> > 
> > Entry corresponding to 220 us setup time was missing. I am not
> > aware
> > of
> > any specific bug this fixes, but this could potentially result in
> > enabling
> > PSR on a panel with a higher setup time requirement than supported
> > by
> > the
> > hardware.
> It should be 'a lower setup time'.
> Sink sets 2h requesting 220us but source will only wait 165us.

By hardware, I meant source :) We'll end up enabling PSR on a sink with
a higher setup time requirement (220us) than supported by the source
hardware (let's say 200 us) because we read the sink requirement as 165
us.


> 
> Other than that looks good:
> Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
> 
Thanks!

I'll resend this along the other PSR patch you reviewed.

> > 
> > 
> > I verified the value is present in eDP spec versions 1.3, 1.4 and
> > 1.4a.
> > 
> > Fixes: 6608804b3d7f ("drm/dp: Add drm_dp_psr_setup_time()")
> > Cc: stable@vger.kernel.org
> > Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
> > Cc: Jose Roberto de Souza <jose.souza@intel.com>
> > Signed-off-by: Dhinakaran Pandiyan <dhinakaran.pandiyan@intel.com>
> > ---
> >  drivers/gpu/drm/drm_dp_helper.c | 1 +
> >  1 file changed, 1 insertion(+)
> > 
> > diff --git a/drivers/gpu/drm/drm_dp_helper.c
> > b/drivers/gpu/drm/drm_dp_helper.c
> > index 36c7609a4bd5..a7ba602a43a8 100644
> > --- a/drivers/gpu/drm/drm_dp_helper.c
> > +++ b/drivers/gpu/drm/drm_dp_helper.c
> > @@ -1159,6 +1159,7 @@ int drm_dp_psr_setup_time(const u8
> > psr_cap[EDP_PSR_RECEIVER_CAP_SIZE])
> >  	static const u16 psr_setup_time_us[] = {
> >  		PSR_SETUP_TIME(330),
> >  		PSR_SETUP_TIME(275),
> > +		PSR_SETUP_TIME(220),
> >  		PSR_SETUP_TIME(165),
> >  		PSR_SETUP_TIME(110),
> >  		PSR_SETUP_TIME(55),