Re: [PATCH 5/5] drm/i915: enable fastboot by default

[Daniel Vetter <daniel@ffwll.ch>]

On Fri, Jun 06, 2014 at 02:12:44PM +0300, Jani Nikula wrote:
> On Thu, 05 Jun 2014, Jesse Barnes <jbarnes@virtuousgeek.org> wrote:
> > Let them eat mincemeat pie.
> >
> > Signed-off-by: Jesse Barnes <jbarnes@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,
> 
> The answer to the ultimate question of life, the universe, and
> everything should simply be "true" here. Personally, I don't think it's
> a bad answer.
> 
> >  	.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);
> 
> Side note, why do we allow the param to be changed after boot?

Because fastboot works for every modeset, or at least should. E.g. if you
go from an upscale panel resolotion to the full one we still want to just
fixup the pfit, even when it's a normal modeset.

So fastboot really is a bit a misnomer, since the leftover bits (after
I've convinced Jesse that the fb takeover should be done unconditionally
really) is just some modeset fastpaths.

Aside: We still have a leak on the inherited fb, see

https://bugs.freedesktop.org/show_bug.cgi?id=77511

-Daniel

> 
> BR,
> Jani.
> 
> >  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)");
> >  
> >  module_param_named(prefault_disable, i915.prefault_disable, bool, 0600);
> >  MODULE_PARM_DESC(prefault_disable,
> > -- 
> > 1.8.3.2
> >
> > _______________________________________________
> > dri-devel mailing list
> > dri-devel@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/dri-devel
> 
> -- 
> Jani Nikula, Intel Open Source Technology Center
> _______________________________________________
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> dri-devel@lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/dri-devel

-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch