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

[Ausmus, James]

On Thu, Oct 12, 2017 at 1:59 PM, Rodrigo Vivi <rodrigo.vivi at intel.com> wrote:
> 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?

Done - thanks!

-James

>
> 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



-- 


James Ausmus