[Intel-gfx] [PATCH v2 2/2] drm/i915/bdw: Fix DP_AUX_CH_CTL_TIME_OUT setting

[Rodrigo Vivi]

On Thu, Oct 12, 2017 at 06:58:20PM +0000, Ausmus, James wrote:
> On Wed, Oct 4, 2017 at 3:54 PM, Runyan, Arthur J
> <arthur.j.runyan at intel.com> wrote:
> > I think the failure was with one particularly slow eDP panel, but it is safer to apply this to all ports.
> >
> 
> Thanks Art. Anyone else have thoughts/comments on this, or should this
> be good for merge now?

There was a warning on CI. And v2 didn't get fully tested because CI got
confused about name changes on v2.

So, could you please resend as a new series. Without the "in-reply-to"
so we get the full CI run on it?

Thanks,
Rodrigo

> 
> Thanks!
> 
> -James
> 
> > -----Original Message-----
> > From: Vivi, Rodrigo
> > Sent: Wednesday, 4 October, 2017 1:25 PM
> > To: Ausmus, James <james.ausmus at intel.com>
> > Cc: intel-gfx at lists.freedesktop.org; ville.syrjala at linux.intel.com; jani.nikula at linux.intel.com; Runyan, Arthur J <arthur.j.runyan at intel.com>; ben at bwidawsk.net
> > Subject: Re: [PATCH v2 2/2] drm/i915/bdw: Fix DP_AUX_CH_CTL_TIME_OUT setting
> >
> > On Wed, Oct 04, 2017 at 08:09:22PM +0000, James Ausmus wrote:
> >> Per BSpec, 400us is "BDW+ Do not use this setting." - not just PORT_A.
> >> Set BDW to 600us unconditionally.
> >
> > Besides that statement I also found on BSpec:
> >
> > "
> > Workaround
> > Project
> > BDW, EXCLUDE(CHV)
> > Set the Timeout timer value to at least 600us before initiating a transaction.
> > "
> >
> > Also I tracked this on the log and arrived to commit 'a81a507d487c
> > ("drm/i915/bdw: Change dp aux timeout to 600us on DDIA")'
> >
> > It seems during BDW enabling HW team found that need but only for port A
> > and later they might have extended it and we never noticed.
> >
> > Ccin't Art and Ben here to see if they can comment on that.
> >
> > But I believe we should add this so
> >
> > Reviewed-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
> >
> >>
> >> v2:
> >> -Split in to two patches (Rodrigo)
> >>
> >> Cc: Jani Nikula <jani.nikula at linux.intel.com>
> >> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> >> Signed-off-by: James Ausmus <james.ausmus at intel.com>
> >> ---
> >>  drivers/gpu/drm/i915/intel_dp.c | 2 +-
> >>  1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
> >> index 5b4c9484575b..df301e00d9d9 100644
> >> --- a/drivers/gpu/drm/i915/intel_dp.c
> >> +++ b/drivers/gpu/drm/i915/intel_dp.c
> >> @@ -1019,7 +1019,7 @@ static uint32_t g4x_get_aux_send_ctl(struct intel_dp *intel_dp,
> >>       else
> >>               precharge = 5;
> >>
> >> -     if (IS_BROADWELL(dev_priv) && intel_dig_port->port == PORT_A)
> >> +     if (IS_BROADWELL(dev_priv))
> >>               timeout = DP_AUX_CH_CTL_TIME_OUT_600us;
> >>       else
> >>               timeout = DP_AUX_CH_CTL_TIME_OUT_400us;
> >> --
> >> 2.14.1
> >>
> 
> 
> 
> -- 
> 
> 
> James Ausmus