[Intel-gfx] [PATCH] drm/i915: Enable fastboot by default on Skylake and newer

[Hans de Goede]

Hi,

On 25-01-19 09:36, Hans de Goede wrote:
> Hi Rodrigo and Maarten,
> 
> On 24-01-19 23:20, Rodrigo Vivi wrote:
>> On Thu, Jan 24, 2019 at 02:01:14PM +0100, Maarten Lankhorst wrote:
>>> From: Hans de Goede <hdegoede at redhat.com>
>>>
>>> We really want to have fastboot enabled by default to avoid an ugly
>>> modeset during boot.
>>>
>>> Rather then enabling it everywhere, lets start with enabling it on
>>> Skylake and newer.
>>>
>>> Signed-off-by: Hans de Goede <hdegoede at redhat.com>
>>> Signed-off-by: Maarten Lankhorst <maarten.lankhorst at linux.intel.com>
>>
>>
>> I believe at this point you both addressed all of my concerns.
>> And CI is happy. Let's give a try ;)
> 
> Great, thank you.
> 
> On IRC Maarten asked me about if we should also enable this for
> VLV/CHV. As you may know, as a spare time/weekend project, I've been
> working on making Linux support Bay and Cherry Trail based hardware,
> better. As such I've about 40 different devices with these SoCs and
> I've tested fastboot=1 on all of them. fastboot=1 not only works on
> all of them, on 2 devices the display goes black when we have
> fastboot=0 for some reason which I've been unable to figure out.
> These 2 devices do survive a full-modeset just fine after the initial
> one ?
> 
> So my response to Maarten was, yes we should enable fastboot=1 by
> default on VLV/CHV too and I plan to submit a follow-up patch for
> that once we have agreement on this patch.
> 
> Maarten suggested to just go for enabling it on gen7+ instead of
> the current gen9+.
> 
> I personally tend towards merging this patch with your
> Reviewed-by + doing a follow-up patch for just VLV/CHV, but
> Maarten prefers doing the gen7+ solution, what is your take on this?

I've gone ahead and pushed this patch to dinq now. I will post a
follow-up patch to also enable fastboot on VLV/CHV.

Then once this mix has seen enough testing out there (and assuming the
testing goes well) then we can try to change to enabling fastboot
by default on gen7+.

Regards,

Hans