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Subject: Re: Resume without drm driver results in black screen
To: Johannes Lundberg <johalun0@gmail.com>,
 freebsd-current <freebsd-current@freebsd.org>
References: <CAECmPwu2fHQMFPpMt5uEy_iFQ+skMGOe3YOpRn64sBAxw69Fyw@mail.gmail.com>
From: John Baldwin <jhb@FreeBSD.org>
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Date: Fri, 15 Jun 2018 15:19:11 -0700
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On 5/17/18 3:01 AM, Johannes Lundberg wrote:
> Hi
> 
> I revived this old bug
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=213501
> 
> Considering this also affects all X users using scfb driver it's worth
> investigating.

It's just not doable.  You need some sort of driver for the GPU that knows
how to turn the display back on.  That isn't a portable thing, it's GPU-specific.
You could perhaps write smaller drivers that only support resume and not
graphics acceleration, but that doesn't seem trivial.

-- 
John Baldwin