[PATCH v4 24/80] drm/omap: dsi: move TE GPIO handling into core

[Tony Lindgren]

* Tomi Valkeinen <tomi.valkeinen at ideasonboard.com> [210217 07:42]:
> On 11/02/2021 19:35, Tony Lindgren wrote:
> > * Tomi Valkeinen <tomi.valkeinen at ideasonboard.com> [210211 07:35]:
> >> On 08/02/2021 19:55, Tony Lindgren wrote:
> >>> Hi,
> >>>
> >>> * Tomi Valkeinen <tomi.valkeinen at ti.com> [201124 12:47]:
> >>>> From: Sebastian Reichel <sebastian.reichel at collabora.com>
> >>>>
> >>>> In preparation for removing custom DSS calls from the DSI
> >>>> panel driver, this moves support for external tearing event
> >>>> GPIOs into the DSI host driver. This way tearing events are
> >>>> always handled in the core resulting in simplification of
> >>>> the panel drivers.
> >>>>
> >>>> The TE GPIO acquisition follows works in the same way as the
> >>>> exynos DSI implementation.
> >>>
> >>> Looks like this patch causes the following warnings:
> >>>
> >>> DSI: omapdss DSI error: Failed to receive BTA
> >>> DSI: omapdss DSI error: bta sync failed
> >>> DSI: omapdss DSI error: vc(0) busy when trying to config for VP
> >>> DSI: omapdss DSI error: Failed to receive BTA
> >>> DSI: omapdss DSI error: bta sync failed
> >>> DSI: omapdss DSI error: vc(0) busy when trying to config for VP
> >>> DSI: omapdss DSI error: Failed to receive BTA
> >>> DSI: omapdss DSI error: bta sync failed
> >>> DSI: omapdss DSI error: vc(0) busy when trying to config for VP
> >>> ...
> >>>
> >>> Any ideas? The display works for me despite the constant
> >>> warnings.
> >>
> >> Which board is that? Do the errors start right from the boot, or only
> >> after running something in userspace?
> > 
> > This is with droid4, that's about the only device I use with a display
> > on regular basis. I'm pretty sure some earlier version of Sebastian's
> > patches worked fine.
> 
> OMAP4 SDP doesn't produce these errors and the HW looks rather
> identical. Although I noticed something odd there, running kmstest
> --flip on the first display works fine, but running on the second
> display gets a bit erratic fps. Which is a bit odd as everything should
> be identical.

Oh cool that you have those running again/still :) In this case there
is no te-gpios if that might make a difference.

> So these errors start from the boot? Or only when running something
> specific?

They start from the boot when modules are loaded.

> Is there a bootloader that initializes the display?

Yes it boots with kexec.

Regards,

Tony