Re: bin/57591: i915 graphics console goes blank during boot

[Havard Eidnes <he%NetBSD.org@localhost>]

> 	Booting this PC (HP EliteDesk 800 G1 SFF) which has an i7-4790
> 	CPU and uses the built-in graphics hardware gives one of two
> 	results:
> 
> 	1) with the VGA screen as console, the two screens I have
> 	   connected both go blank and enter "energy save mode" before
> 	   the boot completes
> 
> 	2) with a serial console, the boot succeeds, and I get a login
> 	   prompt on both screens, and X11 can be started the usual
> 	   way after login (I'm old-fashioned and use startx).
> 
> 	Incidently, this was the state of NetBSD 10.0_BETA as of Thu
> 	Jan 12, but it remains as current behaviour with this recent
> 	NetBSD 10.0_BETA from Fri Aug 18.
> 
> 	Given that the screen goes blank, it's a little hard to tell
> 	if the kernel has crashed or whether this only affects the
> 	screen output (although I could perhaps wait to see if the
> 	network is configured...).

I got a hint to try with a kernel with DDB_ONPANIC=0, and do a
second boot using the serial console (which makes it work), to
collect any kernel messages to narrow down the problem.

However, I also updated to the latest netbsd-10 code at the time

% uname -a
NetBSD xxxxxx.uninett.no 10.0_RC3 NetBSD 10.0_RC3 (GENERIC) #9: Mon Feb  5 17:38:53 CET 2024  he%xxxxx.uninett.no@localhost:/usr/obj/sys/arch/amd64/compile/GENERIC amd64
%

and I'm now happy to report that this system no longer needs to
use the serial console to come properly up.

This update included the recent pull-up which included these
files:

P sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_mman.c
P sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_pages.c
P sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_phys.c
P sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_region.c
P sys/external/bsd/drm2/dist/drm/i915/gem/i915_gem_stolen.c

The last part of dmesg now displays:

[     3.518584] boot device: wd0
[     3.518584] root on wd0a dumps on wd0b
[     3.548584] root file system type: ffs
[     3.558584] kern.module.path=/stand/amd64/10.0/modules
[     3.568583] [drm] Supports vblank timestamp caching Rev 2 (21.10.2013).
[     3.568583] [drm] Driver supports precise vblank timestamp query.
[     3.568583] i915drmkms0: interrupting at msi5 vec 0 (i915drmkms0)
[     3.568583] [drm] Initialized i915 1.6.0 20200114 for i915drmkms0 on minor 0
[     3.608592] i915drmkms0: [drm] Cannot find any crtc or sizes
[     3.618582] [drm] DRM_I915_DEBUG enabled
[     3.618582] [drm] DRM_I915_DEBUG_GEM enabled
[     3.758584] intelfb0 at i915drmkms0
[     3.758584] warning: /usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_uncore.c:1197: Unclaimed write to register 0x41000
[     3.758584] warning: /usr/src/sys/external/bsd/drm2/dist/drm/i915/intel_uncore.c:1197: Unclaimed read from register 0x41000
[     3.758584] intelfb0: framebuffer at 0xe0009000, size 2560x1440, depth 32, stride 10240
[     3.828583] wsdisplay0 at intelfb0 kbdmux 1: console (default, vt100 emulation), using wskbd0
[     3.828583] wsmux1: connecting to wsdisplay0
[    16.228577] wsdisplay0: screen 1 added (default, vt100 emulation)
[    16.228577] wsdisplay0: screen 2 added (default, vt100 emulation)
[    16.228577] wsdisplay0: screen 3 added (default, vt100 emulation)
[    16.228577] wsdisplay0: screen 4 added (default, vt100 emulation)

and it now basically works, currently running dual-headed in-tree
X11 server, using the "modesetting" driver.

Regards,

- Håvard