[Intel-gfx] [PATCH 06/16] drm/i915: Don't call modeset related functions when display is disabled

[Souza, Jose]

On Mon, 2018-10-22 at 12:00 +0300, Jani Nikula wrote:
> On Mon, 22 Oct 2018, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> > Quoting Jani Nikula (2018-10-22 09:25:45)
> > > On Fri, 12 Oct 2018, José Roberto de Souza <jose.souza at intel.com>
> > > wrote:
> > > > Display features should not be initialized or deinitialized
> > > > when
> > > > display is disabled.
> > 
> > I completely disagree with this assertion. If the display is
> > disabled,
> > so must all the associated hw so that we can power down the entire
> > chipset when idle. That means we have to complete the probe (so we
> > continue to rely on fuses and in place of accurate fuses pci-id
> > quirks
> > for the infamous chipsets) and switch it off.
> 
> That actually doesn't contradict with what I said about
> HAS_DISPLAY(). In many cases I think the early return on no display
> is
> the right thing to do. However, no display isn't the same as display
> disabled by module parameter (or whatnot)... which does require probe
> before disable to achieve the power down.
> 
> But is the power down on display disable by module parameter a
> requirement for us?

Okay so I will continue with the current approach to not initialize
display stuff when HAS_DISPLAY() == false.

Also Jani could you take a look into the first 5 patches? Those are
moving some display initialization/uninitialization to proper
functions.


> 
> BR,
> Jani.
> 
>