[Intel-gfx] [PATCH 5/5] drm/i915: enable fastboot by default

[Jesse Barnes]

On Tue, 10 Jun 2014 11:01:06 -0700
Stéphane Marchesin <stephane.marchesin at gmail.com> wrote:

> On Tue, Jun 10, 2014 at 10:31 AM, Jesse Barnes <jbarnes at virtuousgeek.org> wrote:
> > On Tue, 10 Jun 2014 16:07:44 +0200
> > Daniel Vetter <daniel at ffwll.ch> wrote:
> >
> >> On Thu, Jun 05, 2014 at 11:24:31AM -0700, Jesse Barnes wrote:
> >> > Let them eat mincemeat pie.
> >> >
> >> > Signed-off-by: Jesse Barnes <jbarnes at virtuousgeek.org>
> >> > ---
> >> >  drivers/gpu/drm/i915/i915_params.c | 4 ++--
> >> >  1 file changed, 2 insertions(+), 2 deletions(-)
> >> >
> >> > diff --git a/drivers/gpu/drm/i915/i915_params.c b/drivers/gpu/drm/i915/i915_params.c
> >> > index d05a2af..081ab2f 100644
> >> > --- a/drivers/gpu/drm/i915/i915_params.c
> >> > +++ b/drivers/gpu/drm/i915/i915_params.c
> >> > @@ -41,7 +41,7 @@ struct i915_params i915 __read_mostly = {
> >> >     .preliminary_hw_support = IS_ENABLED(CONFIG_DRM_I915_PRELIMINARY_HW_SUPPORT),
> >> >     .disable_power_well = 1,
> >> >     .enable_ips = 1,
> >> > -   .fastboot = 0,
> >> > +   .fastboot = 42,
> >> >     .prefault_disable = 0,
> >> >     .reset = true,
> >> >     .invert_brightness = 0,
> >> > @@ -132,7 +132,7 @@ MODULE_PARM_DESC(enable_ips, "Enable IPS (default: true)");
> >> >
> >> >  module_param_named(fastboot, i915.fastboot, bool, 0600);
> >> >  MODULE_PARM_DESC(fastboot,
> >> > -   "Try to skip unnecessary mode sets at boot time (default: false)");
> >> > +   "Try to skip unnecessary mode sets at boot time (default: true)");
> >>
> >> Nah, that wasn't the intention of this option. It was meant as a hack to
> >> experiment around with fastboot and get things going, but imo we need to
> >> really do the full modeset and short-circuit if the state matches.
> >>
> >> And there's still a bunch of things we don't track like infoframes which
> >> we either need to fix up (similar to the pfit fixup) or quirk to disallow
> >> fastboot.
> >
> > Hm that contradicts our earlier discussions w/Damien when we decided
> > the infoframes stuff were too esoteric to matter...
> 
> My 2 cents is that I've seen some really bad TVs which didn't work
> because infoframes were missing (IIRC it relied on the VIC to detect
> the video mode).

Yeah so we'd still leave them in place in this case, and apply them on
the next mode set as well, but we wouldn't be explicitly cross checking
for them, at least not yet.

It's a good thing to add, I just didn't think it was a blocker based on
our last discussion about this.

-- 
Jesse Barnes, Intel Open Source Technology Center