Ville, any comments here?

Any additional info I can provide here to help?

Thanks for asking. Can you please verify the issue with latest drmtip?
(https://cgit.freedesktop.org/drm-tip)

This is to ensure that this issue still persists with drmtip. This will be useful during investigation.

FWIW you can find prebuilt binary [1] for Ubuntu.

[1] https://kernel.ubuntu.com/~kernel-ppa/mainline/drm-tip/

Created attachment 143696 [details]
updated_dmesg

@Lakshmi / @Kai-Heng

Tried cod/tip/drm-tip/2019-03-16 mainline build but still same issue.

When I switch over to another KVM input, and switch back to the NUC, black screen and can't do anything. The only way to recover is hard reboot of the NUC.

new dmesg attached.

Created attachment 143697 [details]
drm-tip install messages

drm-tip install messages

> new dmesg attached.

Can you please set kernel parameters drm.debug=0x1e log_buf_len=4M and attach the log from boot.

Created attachment 143731 [details]
dmesg with boot parameters

Thanks for the help. Please see attached file for dmesg with boot params.

Let me know what else I can provide.

HI @Lakshmi,

This still isn't working for me - I even tried another KVM - is there anything further I can provide to help debug?

Hi @stuart, can you please provide display_info as well?
cat /sys/kernel/debug/dri/0/i915_display_info
Will try reproducing the issue and get back to you.

(In reply to Stuart from comment #10)
> HI @Lakshmi,
> 
> This still isn't working for me - I even tried another KVM - is there
> anything further I can provide to help debug?

(In reply to Swati Sharma from comment #11)
> Hi @stuart, can you please provide display_info as well?
> cat /sys/kernel/debug/dri/0/i915_display_info
> Will try reproducing the issue and get back to you.

No feedback from more than a month. Dropping the priority of the issue to Medium.
Stuart, can you please provide requested details?

Created attachment 145825 [details]
cat /sys/kernel/debug/dri/0/i915_display_info

Sorry for delay - missed the previous messages.

Please find output of cat /sys/kernel/debug/dri/0/i915_display_info on a fresh install of Ubuntu 19.10 with same issue. Only one monitor is showing.

Also to re-confirm as of today.

This is on an Intel NUC7i7BNH with BIOS 0080 running Ubuntu 19.10 (uname -r
5.3.0-19-generic).

It is a LINKUP 2019 Thunderbolt 3 to Dual DisplayPort 1.2 into an Aten CS1944DP KVM switch.

(In reply to Swati Sharma from comment #11)
> Hi @stuart, can you please provide display_info as well?
> cat /sys/kernel/debug/dri/0/i915_display_info
> Will try reproducing the issue and get back to you.

(In reply to Stuart from comment #13)
> Created attachment 145825 [details]
> cat /sys/kernel/debug/dri/0/i915_display_info
> 
> Sorry for delay - missed the previous messages.
> 
> Please find output of cat /sys/kernel/debug/dri/0/i915_display_info on a
> fresh install of Ubuntu 19.10 with same issue. Only one monitor is showing.

CC'ing Swati.

(In reply to Stuart from comment #14)
> Also to re-confirm as of today.
> 
> This is on an Intel NUC7i7BNH with BIOS 0080 running Ubuntu 19.10 (uname -r
> 5.3.0-19-generic).
> 
> It is a LINKUP 2019 Thunderbolt 3 to Dual DisplayPort 1.2 into an Aten
> CS1944DP KVM switch.

Hi Stuart,
Can you please check whether its the same issue as in https://bugs.freedesktop.org/show_bug.cgi?id=112212 ?

@Swati / @Lakshmi - I don't believe so.

Anything else I can provide @Swati @Lakshmi?

Hi, Just this week there some was fix made. I actually have same NUC7i7BNH and with that both Thunderbolt dock and from that to DP-MST monitor => that to normar just worked now. Also now I have Lenovo MST HUB connected to monitor and that also works now. Can you try now with latest drm-tip and exactly fix that Laksmi informed: https://bugs.freedesktop.org/show_bug.cgi?id=112212 however that was also regression. 

But can you still try with latest-drm-tip as that now works for me too. 
Can you also attach /sys/kernel/debug/dri/0/i915_dp_mst_info

@Jani

Is this done by installing the latest mainline kernel (v5.4-rc7) and then applying the patch?

How do I apply the patch?

It is merged to drm-tip, can you use that? 
https://cgit.freedesktop.org/drm-tip

@Jani, I did the following:

I cloned drm-tip from git://anongit.freedesktop.org/drm-tip and then ran `make defconfig`, `make`, `sudo make modules_install`, `sudo make install` and then rebooted.

My LUKS password wouldn't work at all for an unknown reason and no WiFi device. I reinstalled Ubuntu 19.10 with no LUKS and reran the above drm-tip install. Still no WiFi and still no dual DP monitors.

See below.

stuart@SSH-NUC:~/drm-tip$ sudo cat /sys/kernel/debug/dri/0/i915_dmc_info
fw loaded: no
path: i915/kbl_dmc_ver1_04.bin
program base: 0xfffffdfe
ssp base: 0x00000000
htp: 0x00000000


stuart@SSH-NUC:~/drm-tip$ dmesg | grep i915
[    0.415019] i915 0000:00:02.0: Found 64MB of eDRAM
[    0.415071] i915 0000:00:02.0: vgaarb: deactivate vga console
[    0.419134] i915 0000:00:02.0: vgaarb: changed VGA decodes: olddecodes=io+mem,decodes=io+mem:owns=io+mem
[    0.419167] i915 0000:00:02.0: Direct firmware load for i915/kbl_dmc_ver1_04.bin failed with error -2
[    0.419168] i915 0000:00:02.0: Failed to load DMC firmware i915/kbl_dmc_ver1_04.bin. Disabling runtime power management.
[    0.419169] i915 0000:00:02.0: DMC firmware homepage: https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/i915
[    0.727855] [drm] Initialized i915 1.6.0 20191101 for 0000:00:02.0 on minor 0
[    0.918841] fbcon: i915drmfb (fb0) is primary device
[    0.946780] i915 0000:00:02.0: fb0: i915drmfb frame buffer device



stuart@SSH-NUC:~/drm-tip$ dmesg | grep failed
[    0.419167] i915 0000:00:02.0: Direct firmware load for i915/kbl_dmc_ver1_04.bin failed with error -2
[    0.688530] [drm] failed to retrieve link info, disabling eDP
[    1.017595] platform regulatory.0: Direct firmware load for regulatory.db failed with error -2
[    1.017596] cfg80211: failed to load regulatory.db


In settings my thunderbolt -> dual DP port adapter says "No Thunderbolt support" "Thunderbolt security level could not be determined"

Let me know what we need to try next.

Sorry, should have clarified. One of the two monitors works via the Thunderbolt -> dual DP adapter.

I reinstalled Ubuntu 19.10 with no LUKS and reran the above drm-tip
> install. Still no WiFi and still no dual DP monitors.
> 
Can you please attch the full dmesg here with kernel parameters drm.debug=0x1e log_buf_len=4M?

Not necessarily related to this issue at all but have you checked you have fw (dmc) eg in /lib/firmware/i915 ?

Also wifi not working is separate. This propably just kernel config issue and not related to drm-tip as such.

As you see from our CI KBL NUC (not same but anyway)
http://gfx-ci.fi.intel.com/tree/drm-tip/IGT_5292/fi-kbl-7500u/boot0.txt
<7>[    4.905598] [drm:intel_csr_ucode_init [i915]] Loading i915/kbl_dmc_ver1_04.bin
<6>[    4.907977] [drm] Finished loading DMC firmware i915/kbl_dmc_ver1_04.bin (v1.4)
<7>[    4.908643] [drm:intel_fbc_init [i915]] Sanitized enable_fbc value: 1

-- GitLab Migration Automatic Message --

This bug has been migrated to freedesktop.org's GitLab instance and has been closed from further activity.

You can subscribe and participate further through the new bug through this link to our GitLab instance: https://gitlab.freedesktop.org/drm/intel/issues/702.