xorg gives low resolution on HDMI port

[Peter Jaeckel]

This is a Zotac CI547 box. It has to video outputs: one HDMI and one DisplayPort. The HDMI port appears as DP-1 in the logs, the DisplayPort as DP-2. The hardware is Intel HD 620 and is allegedly able to run two displays simultaneously at 4K. I have one WQHD monitor (=2560x1440) and I get that full resolution over the DisplayPort. However, I would like to also get that resolution over the HDMI port (in order to connect two identical monitors), but over HDMI I only get 1024x768. Updating the kernel to the latest 4.18.8 using UKUU made no difference.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: xorg 1:7.7+19ubuntu7.1
Uname: Linux 4.18.8-041808-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.3
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
CurrentDesktop: X-Cinnamon
Date: Sat Sep 22 00:21:15 2018
DistUpgraded: Fresh install
DistroCodename: bionic
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes
GraphicsCard:
 Intel Corporation HD Graphics 620 [8086:5916] (rev 02) (prog-if 00 [VGA controller])
   Subsystem: Intel Corporation HD Graphics 620 [8086:0000]
InstallationDate: Installed on 2018-09-19 (2 days ago)
InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64 (20180725)
MachineType: ZOTAC ZBOX-CI527/CI547
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.8-041808-generic root=UUID=a3c0f54d-b5ae-4a0f-89ec-8e47ad34e2ef ro quiet splash acpi_backlight=native pci=nomsi resume=UUID=a3c0f54d-b5ae-4a0f-89ec-8e47ad34e2ef resume_offset=34816 vt.handoff=1
SourcePackage: xorg
Symptom: display
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 04/25/2017
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: B331P206
dmi.board.asset.tag: NA
dmi.board.name: ZBOX-CI527/CI547
dmi.board.vendor: ZOTAC
dmi.board.version: XX
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 9
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrB331P206:bd04/25/2017:svnZOTAC:pnZBOX-CI527/CI547:pvrXX:rvnZOTAC:rnZBOX-CI527/CI547:rvrXX:cvnDefaultstring:ct9:cvrDefaultstring:
dmi.product.family: NA
dmi.product.name: ZBOX-CI527/CI547
dmi.product.sku: NA
dmi.product.version: XX
dmi.sys.vendor: ZOTAC
version.compiz: compiz N/A
version.libdrm2: libdrm2 2.4.91-2
version.libgl1-mesa-dri: libgl1-mesa-dri 18.0.5-0ubuntu0~18.04.1
version.libgl1-mesa-glx: libgl1-mesa-glx 18.0.5-0ubuntu0~18.04.1
version.xserver-xorg-core: xserver-xorg-core 2:1.19.6-1ubuntu4
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:18.0.1-1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.99.917+git20171229-1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.15-2

[Timo Aaltonen (tjaalton)]

You probably need to file it upstream at bugs.freedesktop.org (DRI; DRM/Intel)

[Peter Jaeckel (peter-jaeckel)]

I hear you.
It happens both with the intel driver and with the standard 'modesetting' driver.
Quite a few people appear to have this problem from what I could glean out there.
I understand the reluctance at this layer to look into this, but it is a fairly common problem, and I get the impression wherever I see this reported that there is no-one even trying.

I am not blaming anyone here.

I was simply hoping for a bit more help than passing this off as some other group's issue.
I have probably already spent 12h+ with many attempts to bypass this, trying different monitors, modelines, looking for newer intel driver versions, switching to and fro between the intel and the standard driver, overriding edid info, different HDMI cables, different kernel versions (as far as I could get them). I have run out of ideas and lost *a lot* of sleep.

Thanks.

[Joseph Salisbury (jsalisbury)]

Would it be possible for you to test the latest upstream kernel? Refer to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest v4.19 kernel[0].

If this bug is fixed in the mainline kernel, please add the following tag 'kernel-fixed-upstream'.

If the mainline kernel does not fix this bug, please add the tag: 'kernel-bug-exists-upstream'.

Once testing of the upstream kernel is complete, please mark this bug as "Confirmed".

Thanks in advance.

[0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19-rc5

[Peter Jaeckel (peter-jaeckel)]

I will do so with great pleasure on Tuesday (happen to be on a business
trip at this moment).

Thank you many times for trying to help!

pj

On Wed, 26 Sep 2018, 21:01 Joseph Salisbury, <email address hidden>
wrote:

> Would it be possible for you to test the latest upstream kernel? Refer
> to https://wiki.ubuntu.com/KernelMainlineBuilds . Please test the latest
> v4.19 kernel[0].
>
> If this bug is fixed in the mainline kernel, please add the following
> tag 'kernel-fixed-upstream'.
>
> If the mainline kernel does not fix this bug, please add the tag:
> 'kernel-bug-exists-upstream'.
>
> Once testing of the upstream kernel is complete, please mark this bug as
> "Confirmed".
>
>
> Thanks in advance.
>
> [0] http://kernel.ubuntu.com/~kernel-ppa/mainline/v4.19-rc5
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1793837
>
> Title:
> xorg gives low resolution on HDMI port
>
> Status in linux package in Ubuntu:
> Confirmed
>
> Bug description:
> This is a Zotac CI547 box. It has to video outputs: one HDMI and one
> DisplayPort. The HDMI port appears as DP-1 in the logs, the
> DisplayPort as DP-2. The hardware is Intel HD 620 and is allegedly
> able to run two displays simultaneously at 4K. I have one WQHD monitor
> (=2560x1440) and I get that full resolution over the DisplayPort.
> However, I would like to also get that resolution over the HDMI port
> (in order to connect two identical monitors), but over HDMI I only get
> 1024x768. Updating the kernel to the latest 4.18.8 using UKUU made no
> difference.
>
> ProblemType: Bug
> DistroRelease: Ubuntu 18.04
> Package: xorg 1:7.7+19ubuntu7.1
> Uname: Linux 4.18.8-041808-generic x86_64
> ApportVersion: 2.20.9-0ubuntu7.3
> Architecture: amd64
> CompizPlugins: No value set for
> `/apps/compiz-1/general/screen0/options/active_plugins'
> CompositorRunning: None
> CurrentDesktop: X-Cinnamon
> Date: Sat Sep 22 00:21:15 2018
> DistUpgraded: Fresh install
> DistroCodename: bionic
> DistroVariant: ubuntu
> ExtraDebuggingInterest: Yes
> GraphicsCard:
> Intel Corporation HD Graphics 620 [8086:5916] (rev 02) (prog-if 00 [VGA
> controller])
> Subsystem: Intel Corporation HD Graphics 620 [8086:0000]
> InstallationDate: Installed on 2018-09-19 (2 days ago)
> InstallationMedia: Ubuntu 18.04.1 LTS "Bionic Beaver" - Release amd64
> (20180725)
> MachineType: ZOTAC ZBOX-CI527/CI547
> ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.18.8-041808-generic
> root=UUID=a3c0f54d-b5ae-4a0f-89ec-8e47ad34e2ef ro quiet splash
> acpi_backlight=native pci=nomsi
> resume=UUID=a3c0f54d-b5ae-4a0f-89ec-8e47ad34e2ef resume_offset=34816
> vt.handoff=1
> SourcePackage: xorg
> Symptom: display
> UpgradeStatus: No upgrade log present (probably fresh install)
> dmi.bios.date: 04/25/2017
> dmi.bios.vendor: American Megatrends Inc.
> dmi.bios.version: B331P206
> dmi.board.asset.tag: NA
> dmi.board.name: ZBOX-CI527/CI547
> dmi.board.vendor: ZOTAC
> dmi.board.version: XX
> dmi.chassis.asset.tag: Default string
> dmi.chassis.type: 9
> dmi.chassis.vendor: Default string
> ...

[Daniel van Vugt (vanvugt)]

The hardware brochure says "HDMI 2.0 (3840x2160 @ 60Hz), HDCP compliant" on
http://hkftp.zotac.com/External/ZBOX/C-series/CI547nano/Brochure/ZBOX-CI547NANO_Brochure.pdf

So the only reasons I can think of for 2560x1440 (which requires only HDMI 1.3) being rejected are:

1. Low quality HDMI cable. Make sure you use a cable that is advertised as supporting 4K. HDMI 1.3 can do 4K at 30Hz and HDMI 2.0 can do 4K at 60Hz.

2. A buggy TV/display returning bad EDID data. That's unlikely but happens occasionally.

[Peter Jaeckel (peter-jaeckel)]

Thank you.

As I mentioned, I spent an extraordinary amount of time on this. I did not
provide an exhaustive list of all my attempts and will not do so now, but
this included, though was not limited to:-

+ Trying at least three different HDMI cables (and I dare mention that the
whole debate about 1.3 vs 1.4 actually refers to the devices; for cables
there's only the official "high speed" category vs the rest based on their
shielding and all wires being connected - these cables are passive and have
no protocol-awareness, though this is an entirely separate debate) all of
which provided higher resolution with a different input device.

+ Trying a different monitor.

+ Reading out the EDID info once via the Displayport cable and once via
HDMI using get-edid and parse-edid, and also parsing the hex EDID info in
the X log file (which was binary identical to what get-edid got).
Interestingly, for the same monitor (but via different input ports) the
EDID info differed in the maximum clock speed and the mode list, but in
both cases included a (non-interlaced) mode at 2560x1440 pixels. The EDID
info is stable - it is identical in repeated readouts (or X startup log
files) for each of the connection modes.

The monitor is not a cheapo TV but a brand new Asus PB328Q (
https://www.asus.com/Commercial-Monitors/PB328Q/). I have at present no
other input devices that would be able to send 2560x1440 down the HDMI
cable, so I cannot test that. I can, however, report, that with kernel
4.18, sometimes (rarely), upon restart, the X server initially starts with
1920x... (over HDMI), and sometimes 1289x..., but when I enter the display
manager, it only offers the 1024x... mode, and actually forces the lower
mode at that point, so there's clearly some inconsistency somewhere (and I
am obviously not excluding this being in the intel HD 620 graphics
hardware). Sometimes the startup mode is then even interlaced, to make
matters even worse.

In mention once more that there are *plenty* of reports out there on
exactly this phenomenon of not getting the top resolution via HDMI with
this (and some other) intel graphics hardware, also, but not only on
official intel/windows support forums where official intel support staff
keep recommending newer versions of the driver until, eventually, those
customers suffering the problem find a version that works for them.

All this may be caused by the intel (HDMI) hardware being flakey, show
unreliable intermittent responses, etc., you name it, but merely
reiterating suggestions that amount to this being simply extraneous or
ultimately the users responsibility (or even fault) is not particularly
helpful. This problem is widely reported! I mean obviously no offense.

I am grateful for any genuine attempt to help and will try out the new
kernel 4.19 asap (still away on business) and report back.

Sincerely,
pj

On Mon, 1 Oct 2018, 10:01 Daniel van Vugt, <email address hidden>
wrote:

> The hardware brochure says "HDMI 2.0 (3840x2160 @ 60Hz), HDCP compliant" on
>
> http://hkftp.zotac.com/External/ZBOX/C-series/CI547nano/Brochure/ZBOX-CI547NANO_Brochure.pdf
>
> So the only reasons I can think of for 2560x1440 (which requires on...

[Peter Jaeckel (peter-jaeckel)]

No change with kernel 4.19.0-041900rc5-generic, alas.

The bizarre thing is the Xorg log (~/.local/share/xorg/Xorg.0.log) saying

 [ 11.016] (II) modeset(0): Supported established timings:

and subsequently the finest mode being 1280x1024@75Hz. Then, in the section(s) called

 [ 11.017] (II) modeset(0): Supported detailed timing:

it does include a mode with "clock: 241.5 MHz" and 2560x1440. It also says later:

 [ 11.017] (--) modeset(0): HDMI max TMDS frequency 250000KHz

so it is happy up to 250MHz. And much later, it says

 [ 11.906] (II) modeset(0): Printing DDC gathered Modelines:
 [ 11.906] (II) modeset(0): Modeline "2560x1440"x0.0 241.50 2560 2608 2640 2720 1440 1443 1448 1481 +hsync -vsync (88.8 kHz eP)

and so on, i.e., including a 2560x1440 mode.

I do not understand that parts are happily talking about the maximum resolution of the monitor via HDMI, and other parts seem to not know anything about it.

Any help welcome. Would you like me to try the intel driver (again)?

pj

[Peter Jaeckel (peter-jaeckel)]

No better luck with 4.19.0-041900rc6-generic.
Upon reboot, running at 1920x1080 *interlaced*. No good - I am getting the shakes just watching the screen. And it is slightly blurred.
Thanks for all the help and hard work!
pj