Re: kern/49398: i386-current GENERIC (i915drmkms) boot hangs if monitor powered off

["John D. Baker" <jdbaker%consolidated.net@localhost>]

The following reply was made to PR kern/49398; it has been noted by GNATS.

From: "John D. Baker" <jdbaker%consolidated.net@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/49398: i386-current GENERIC (i915drmkms) boot hangs if
 monitor powered off
Date: Sun, 20 Aug 2023 12:00:00 -0500 (CDT)

 On Sun, 20 Aug 2023, John D. Baker wrote:
 
 > On Sun, 20 Aug 2023, riastradh%NetBSD.org@localhost wrote:
 > 
 > > Lots of drm updates since this, can you test if it's been fixed in
 > > netbsd-10 or HEAD?
 > 
 > I'll need to test again on more recent builds, but I have an amd64
 > machine (Dell Optiplex 760) with VGA and DisplayPort on which booting
 > netbsd-10 or -current hangs if the DisplayPort LCD display is connected
 > but powered off.  Netbsd-9 has no problems booting with the monitor off,
 > but the monitor won't wake up when powered on again (but ISTR that that
 > is just how DisplayPort is).
 > 
 > I'll see about testing it with the VGA output and see if it behaves
 > differently.
 
 On the Optiplex760 (i82Q45 chipset w/integrated video) with no monitor
 attached _at all_, it hangs during boot.  Attaching a monitor while
 in this state claims no signal present either on DP or VGA.
 
 With the LCD display attached via VGA, the DRMKMS wscons erroneously
 detects the display as 1024x768 (it's 1280x1024).
 
 With the LCD display attached via VGA but powered off, the system boots
 fine.  Turning the monitor on afterwards shows it using 1024x768
 resolution.
 
 > It may be a while before I can test with the original system which
 > spawned this PR.  Lots of clutter to sort out to get the components
 > back within cable's reach of each other.
 
 I think I can relatively easily arrange to test the i82Q45 machine with
 the VGA CRT monitor that started this mess and see how it behaves.
 
 -- 
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