Re: [PATCH 02/14] drm/i915: Reorganize vlv eDP reboot notifier

Ville Syrjälä
2014-08-26T13:30:27Z

On Tue, Aug 26, 2014 at 04:21:00PM +0300, Jani Nikula wrote:
> On Tue, 26 Aug 2014, Ville Syrjälä <ville.syrjala@linux.intel.com> wrote:
> > On Tue, Aug 19, 2014 at 10:00:55AM +0300, Jani Nikula wrote:
> >> On Mon, 18 Aug 2014, ville.syrjala@linux.intel.com wrote:
> >> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >> >
> >> > Move the vlv_power_sequencer_pipe() after the IS_VALLEYVIEW() check
> >> > and flatten the rest of the function.
> >>
> >> Please imagine adding another platform there, and realize this just adds
> >> unnecessary churn.
> >
> > I'd just add another reboot notifier then.
>
> Fair enough; it should be vlv_edp_notify_handler then. (No, don't send a
> patch to change that! ;)
>
> > Frankly I don't understand the current one either. Why does it need to
> > set the delay to max for instance? And does this mean that the
> > PANEL_POWER_RESET bit doesn't actually work as advertised in the docs?
>
> *shrug* experimental evidence?
>
> commit 01527b3127997ef6370d5ad4fa25d96847fbf12a
> Author: Clint Taylor <clinton.a.taylor@intel.com>
> Date: Mon Jul 7 13:01:46 2014 -0700
>
> drm/i915/vlv: T12 eDP panel timing enforcement during reboot
>
> The panel power sequencer on vlv doesn't appear to accept changes to its
> T12 power down duration during warm reboots. This change forces a delay
> for warm reboots to the T12 panel timing as defined in the VBT table for
> the connected panel.

That explanation doesn't really make it any more clear to me. But if the
reboot notifier helps someone somehow I can live with it.

--
Ville Syrjälä
Intel OTC