jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Pi4 4k 60hz issue

Sat Sep 12, 2020 7:40 am

Hello brains trust

I'm just getting started and I'm hoping you'll be able to help me with an issue getting 4k at 60hz working on a pi 4. I can get 4k at 30hz working, or 1080p at 60hz, but can't get 4k at 50hz, 59.94hz or 60hz to work.

The following happens:
- If I enable 4k60p in config.txt, the pi boots to no signal on the monitor.
- If I enable 4k60p in config.txt but have "HDMI Ultra HD Deep Color" disabled on the monitor, it will boot to 4k 30hz, but if I enable Deep Colour and then try to change the resolution to 4k 50/59.94/60hz in the Display Configuration I will get 'no signal' for 10 seconds until the resolution automatically goes back to 30hz.

I am using a new LG 32UK550-B monitor. The monitor's manual says it supports the following at 4k 59.94hz or 60hz:
- YCbCr 4:2:0 (8/10 bit)
- YCbCr 4:2:2 (8/10 bit)
- YCbCr 4:4:4 (8 bit)
- RGB (8 bit)

I don't know enough about HDMI to know what that means but I ascertain from other threads this is important

I have done some research and have tried all of the steps I could find:
- I am using hdmi0
- I have a 5V 4a power source and there are no issues of undervoltage (vcgencmd get_throttled displays "0x0")
- I am using the official pi micro hdmi to hdmi cable
- I have added "hdmi_enable_4k=1" to the boot config
- I have tried turning "config_hdmi_boost" up to 9 (assume the max of 11 is a spinal tap reference?)
- I have tried disabling the VC4 V3D line in config.txt
- I have done sudo apt full-upgrade
- I also tried "hdmi_group=1" and hdmi_mode=97" in config.txt

I saw on another thread that I should run 'tvservice -d edid.dat' and then convert to text using base64 - result below:

Code: Select all

AP///////wAebQZ30L8BAAceAQOAPCJ46j4xrlBHrCcMUFQhCABxQIGAgcCpwNHAgQABAQEBCOgAMPJwWoCwWIoAWFQhAAAeBHQAMPJwWoCwWIoAWFQhAAAaAAAA/QA4PR6HPAAKICAgICAgAAAA/ABMRyBIRFIgNEsKICAgAUkCAzhxTZAiIB8SAwQBYWBdXl8jCQcHbQMMABAAuDwgAGABAgNn2F3EAXiAA+MPAAPjBcAA4wYFAQI6gBhxOC1AWCxFAFhUIQAAHlZeAKCgoClQMCA1AFhUIQAAGgAAAP8AMDA3TlRBQjNDNjQwCgAAAAAAAAAAAAAAAAAAAAAACw==

Code: Select all

Parsing edid.dat...
HDMI:EDID version 1.3, 1 extensions, screen size 60x34 cm
HDMI:EDID features - videodef 0x80 standby suspend active off; colour encoding:RGB444|YCbCr422; sRGB is not default colourspace; preferred format is native; does not support GTF
HDMI:EDID found monitor range descriptor tag 0xfd
HDMI:EDID monitor range offsets: V min=0, V max=0, H min=0, H max=0
HDMI:EDID monitor range: vertical is 56-61 Hz, horizontal is 30-135 kHz, max pixel clock is 600 MHz
HDMI:EDID monitor range does not support GTF
HDMI:EDID found monitor name descriptor tag 0xfc
HDMI:EDID monitor name is LG_HDR_4K
HDMI:EDID found preferred CEA detail timing format: 3840x2160p @ 60 Hz (97)
HDMI:EDID found CEA detail timing format: 3840x2160p @ 30 Hz (95)
HDMI:EDID established timing I/II bytes are 21 08 00
HDMI:EDID found DMT format: code 4, 640x480p @ 60 Hz in established timing I/II
HDMI:EDID found DMT format: code 9, 800x600p @ 60 Hz in established timing I/II
HDMI:EDID found DMT format: code 16, 1024x768p @ 60 Hz in established timing I/II
HDMI:EDID standard timings block x 8: 0x7140 8180 81C0 A9C0 D1C0 8100 0101 0101 
HDMI:EDID unknown standard timing 1152x864 @ 60 Hz aspect ratio (4:3)
HDMI:EDID found DMT format: code 35, 1280x1024p @ 60 Hz (5:4) in standard timing 1
HDMI:EDID found DMT format: code 85, 1280x720p @ 60 Hz (16:9) in standard timing 2
HDMI:EDID found DMT format: code 83, 1600x900p @ 60 Hz (16:9) in standard timing 3
HDMI:EDID found DMT format: code 82, 1920x1080p @ 60 Hz (16:9) in standard timing 4
HDMI:EDID found DMT format: code 28, 1280x800p @ 60 Hz (16:10) in standard timing 5
HDMI:EDID parsing v3 CEA extension 0
HDMI:EDID monitor support - underscan IT formats:no, basic audio:yes, yuv444:yes, yuv422:yes, #native DTD:1
HDMI:EDID found CEA detail timing format: 1920x1080p @ 60 Hz (16)
HDMI:EDID failed to find a matching detail format for 2560x1440p hfp:48 hs:32 hbp:80 vfp:3 vs:5 vbp:33 pixel clock:241 MHz
HDMI:EDID calculated refresh rate is 60 Hz
HDMI:EDID guessing the format to be 2560x1440p @60 Hz
HDMI:EDID found unknown detail timing format: 2560x1440p hfp:48 hs:32 hbp:80 vfp:3 vs:5 vbp:33 pixel clock:241 MHz
HDMI:EDID failed to find a matching detail format for 0x816p hfp:334 hs:84 hbp:-163 vfp:4 vs:33 vbp:1803 pixel clock:0 MHz
HDMI:EDID calculated refresh rate is 0 Hz
HDMI:EDID guessing the format to be 0x816p @24 Hz
HDMI:EDID found unknown detail timing format: 0x816p hfp:334 hs:84 hbp:-163 vfp:4 vs:33 vbp:1803 pixel clock:0 MHz
HDMI:EDID found CEA format: code 16, 1920x1080p @ 60Hz (native)
HDMI:EDID found CEA format: code 34, 1920x1080p @ 30Hz 
HDMI:EDID found CEA format: code 32, 1920x1080p @ 24Hz 
HDMI:EDID found CEA format: code 31, 1920x1080p @ 50Hz 
HDMI:EDID found CEA format: code 18, 720x576p @ 50Hz 
HDMI:EDID found CEA format: code 3, 720x480p @ 60Hz 
HDMI:EDID found CEA format: code 4, 1280x720p @ 60Hz 
HDMI:EDID found CEA format: code 1, 640x480p @ 60Hz 
HDMI:EDID found CEA format: code 97, 3840x2160p @ 60Hz 
HDMI:EDID found CEA format: code 96, 3840x2160p @ 50Hz 
HDMI:EDID found CEA format: code 93, 3840x2160p @ 24Hz 
HDMI:EDID found CEA format: code 94, 3840x2160p @ 25Hz 
HDMI:EDID found CEA format: code 95, 3840x2160p @ 30Hz 
HDMI:EDID found audio format 2 channels PCM, sample rate: 32|44|48 kHz, sample size: 16|20|24 bits
HDMI:EDID found HDMI VSDB length 13
HDMI:EDID HDMI VSDB has physical address 1.0.0.0
HDMI:EDID HDMI VSDB supports AI:yes, dual link DVI:no
HDMI:EDID HDMI VSDB deep colour support - 48-bit:no 36-bit:yes 30-bit:yes DC_yuv444:yes
HDMI:EDID HDMI VSDB max TMDS clock 300 MHz
HDMI:EDID HDMI VSDB does not support content type
HDMI:EDID HDMI VSDB supports extended resolutions 1,2,3
HDMI:EDID ignoring non HDMI VSDB with IEEE reg 0xc45dd8
HDMI:EDID extended data block YCbCr420CapMap - length 3
HDMI:EDID extended data block tag 0x05 length 3 not supported
HDMI:EDID extended data block tag 0x06 length 3 not supported
HDMI:EDID adding mandatory support for CEA (2) 720x480p @ 60Hz
HDMI:EDID adding mandatory support for CEA (17) 720x576p @ 50Hz
HDMI:EDID adding mandatory support for CEA (19) 1280x720p @ 50Hz
HDMI:EDID filtering formats with pixel clock unlimited MHz or h. blanking unlimited
HDMI:EDID best score mode initialised to CEA (1) 640x480p @ 60 Hz with pixel clock 25 MHz (score 0)
HDMI:EDID best score mode is now CEA (1) 640x480p @ 60 Hz with pixel clock 25 MHz (score 61864)
HDMI:EDID best score mode is now CEA (2) 720x480p @ 60 Hz with pixel clock 27 MHz (score 66472)
HDMI:EDID CEA mode (3) 720x480p @ 60 Hz with pixel clock 27 MHz has a score of 66472
HDMI:EDID best score mode is now CEA (4) 1280x720p @ 60 Hz with pixel clock 74 MHz (score 135592)
HDMI:EDID DMT mode (4) 640x480p @ 60 Hz with pixel clock 25 MHz has a score of 18432
HDMI:EDID DMT mode (9) 800x600p @ 60 Hz with pixel clock 40 MHz has a score of 28800
HDMI:EDID best score mode is now CEA (16) 1920x1080p @ 60 Hz with pixel clock 148 MHz (score 4398248)
HDMI:EDID DMT mode (16) 1024x768p @ 60 Hz with pixel clock 65 MHz has a score of 47185
HDMI:EDID CEA mode (17) 720x576p @ 50 Hz with pixel clock 27 MHz has a score of 66472
HDMI:EDID CEA mode (18) 720x576p @ 50 Hz with pixel clock 27 MHz has a score of 66472
HDMI:EDID CEA mode (19) 1280x720p @ 50 Hz with pixel clock 74 MHz has a score of 117160
HDMI:EDID DMT mode (28) 1280x800p @ 60 Hz with pixel clock 83 MHz has a score of 86440
HDMI:EDID CEA mode (31) 1920x1080p @ 50 Hz with pixel clock 148 MHz has a score of 232360
HDMI:EDID CEA mode (32) 1920x1080p @ 24 Hz with pixel clock 74 MHz has a score of 124532
HDMI:EDID CEA mode (34) 1920x1080p @ 30 Hz with pixel clock 74 MHz has a score of 149416
HDMI:EDID DMT mode (35) 1280x1024p @ 60 Hz with pixel clock 108 MHz has a score of 103643
HDMI:EDID DMT mode (82) 1920x1080p @ 60 Hz with pixel clock 148 MHz has a score of 149416
HDMI:EDID DMT mode (83) 1600x900p @ 60 Hz with pixel clock 108 MHz has a score of 111400
HDMI:EDID DMT mode (85) 1280x720p @ 60 Hz with pixel clock 74 MHz has a score of 80296
HDMI:EDID CEA mode (93) 3840x2160p @ 24 Hz with pixel clock 297 MHz has a score of 423130
HDMI:EDID CEA mode (94) 3840x2160p @ 25 Hz with pixel clock 297 MHz has a score of 439720
HDMI:EDID best score mode is now CEA (95) 3840x2160p @ 30 Hz with pixel clock 297 MHz (score 5022664)
HDMI:EDID CEA mode (96) 3840x2160p @ 50 Hz with pixel clock 594 MHz has a score of 356776
HDMI:EDID best score mode is now CEA (97) 3840x2160p @ 60 Hz with pixel clock 594 MHz (score 5622196)
HDMI0:EDID preferred mode remained as CEA (97) 3840x2160p @ 60 Hz with pixel clock 594 MHz
HDMI:EDID has HDMI support and audio support
edidparser exited with code 0
Thanks in advance for your help

6by9
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
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Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:17 am

I have tried turning "config_hdmi_boost" up to 9 (assume the max of 11 is a spinal tap reference?)
- I have tried disabling the VC4 V3D line in config.txt
- I have done sudo apt full-upgrade
- I also tried "hdmi_group=1" and hdmi_mode=97" in config.txt
Don't. None of those things are likely to help.
- I have added "hdmi_enable_4k=1" to the boot config
That's the main thing.

Where did you get your micro-HDMI to HDMI lead from? The quality of leads varies dramatically, and 4k60 makes a far higher demand on the quality of the cable.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:20 am


dom
Raspberry Pi Engineer & Forum Moderator
Raspberry Pi Engineer & Forum Moderator
Posts: 5664
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Location: Cambridge

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:23 am

jamest wrote:
Sat Sep 12, 2020 7:40 am
- I have added "hdmi_enable_4k=1" to the boot config
The setting is `hdmi_enable_4kp60=1`. I suspect you typed it correctly in config.txt if it resulted in no picture (and so had an effect).

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:27 am

Yes that's a good guess, it appears I mistyped it in my post but had it correct in config.txt. I was also able to boot up into 4k30p (through a change in monitor settings) and see 4k60p options in the display config window, so believe this flag was definately correct in config.txt.

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:38 am

My desktop pc and ps4 have no issues with 4k60p, so no issues with thr monitor that I can see fwiw.

fruitoftheloom
Posts: 24552
Joined: Tue Mar 25, 2014 12:40 pm
Location: Delightful Dorset

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 10:51 am

jamest wrote:
Mon Sep 14, 2020 10:38 am
My desktop pc and ps4 have no issues with 4k60p, so no issues with thr monitor that I can see fwiw.


https://www.raspberrypi.org/documentati ... t/video.md

https://www.raspberrypi.org/documentati ... i4-hdmi.md
Thinking outside the box is better than burying your head in the sand...

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Mon Sep 14, 2020 4:11 pm

Sorry I'm not sure I follow what the suggestion is here - the first link is to a listing of all video options and the second is for a resolution of 1366x768, not 4k.

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Thu Sep 17, 2020 8:40 am

I tried swapping out for a different 5V 4A power supply but unfortunately the issue is reoccurring in the same way.

Any further suggestions by any chance? I've got the right settings, power supply is ok, using the official hdmi cable, and the EDID data shows that the monitor should be able to do 4k60p - I am stumped.

6by9
Raspberry Pi Engineer & Forum Moderator
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Re: Pi4 4k 60hz issue

Thu Sep 17, 2020 12:15 pm

I'm a little stumped too.
We jumped through a fair number of hoops to make sure the official cable supports 4k60 as it really does require a decent cable.
I have a couple of 30cm HDMI M-F extension leads that I use instead of having to grope around the back of the monitor. Those are enough to stop 4k working even though they claimed to be HDMI 2.0 (required for 4k60) :-/

As your monitor works with your PC and PS4, but presumably not via the micro HDMI to HDMI lead, I'd suspect the lead to be dodgy.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.

rhildinger
Posts: 39
Joined: Thu Jun 09, 2016 6:07 pm

Re: Pi4 4k 60hz issue

Thu Sep 17, 2020 1:36 pm

It looks possible that you may be having the exact same issue that I'm having. I documented it in this thread but it hasn't gotten much traction:

viewtopic.php?f=28&t=284888

There is a both an easy way and more precise but invovled way to check if you are having the same issue:

The easy way...

Power up your monitor and raspberry pi in 4k60 mode and wait for about 15 minutes, and see if the Pi desktop eventually appears on the display.

The more involved way...

1. Get your pi setup with serial or ssh connectivity such that you can login and get kernel logs even when the display is blank in 4k60 mode. Add the following to the end of the cmdline.txt file in the /boot directory: "drm.debug=0x14"
2. Reboot your pi in 4k60 mode and wait a minute for it to completely boot
3. login to the Pi and execute the command "dmesg" which will dump all the kernel logs with the newly added DRM debug logs
4. Look for logs that look like the following:

Code: Select all

[  247.534702] [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [CRTC:52:crtc-0] flip_done timed out
[  257.774879] [drm:drm_atomic_helper_wait_for_dependencies [drm_kms_helper]] *ERROR* [CONNECTOR:54:HDMI-A-1] flip_done timed out
[  257.774970] [drm:vc4_crtc_atomic_flush [vc4]] [CRTC:52] crtc_atomic_flush.
[  268.015082] [drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:52:crtc-0] flip_done timed out
These logs indicate that DRM is having trouble establishing the video timing mode specified by the EDID info from the monitor.

[Note: Edited post to correct invalid kernel command line flag. The correct flag is "drm.debug=0x14"]

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Fri Sep 18, 2020 4:59 am

rhildinger wrote:
Thu Sep 17, 2020 1:36 pm
It looks possible that you may be having the exact same issue that I'm having. I documented it in this thread but it hasn't gotten much traction:
Thanks for your detailed post and clear instructions. My pi is now booting to 30hz when 60hz is enabled, so I did your method slightly differently by switching to 60hz in the Screen Configuration utility, and running dmesg - results in the attached.
output.zip
(12.79 KiB) Downloaded 11 times
I don't follow what much of this means but I did pick up on the following:

Code: Select all

[  162.483805] [drm:drm_add_display_info [drm]] HDMI: DVI dual 0, max TMDS clock 300000 kHz
[  162.483914] [drm:drm_add_display_info [drm]] HF-VSDB: max TMDS clock 600000 kHz
I ascertain that 297 MHz is not enough for 4k60p. I am not sure what this line means though - is it saying the cable is insufficient, or the monitor is insufficient, or something else?

6by9
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Re: Pi4 4k 60hz issue

Fri Sep 18, 2020 6:59 am

jamest wrote:
Fri Sep 18, 2020 4:59 am
I don't follow what much of this means but I did pick up on the following:

Code: Select all

[  162.483805] [drm:drm_add_display_info [drm]] HDMI: DVI dual 0, max TMDS clock 300000 kHz
[  162.483914] [drm:drm_add_display_info [drm]] HF-VSDB: max TMDS clock 600000 kHz
I ascertain that 297 MHz is not enough for 4k60p. I am not sure what this line means though - is it saying the cable is insufficient, or the monitor is insufficient, or something else?
HDMI < 2.0 maxes out at 300MHz, and this is described in one part of the EDID.
HDMI >= 2.0 have to support scrambling as a spread spectrum EMC-reduction step, and that is described in the HF-VSDB (HDMI Forum Vendor Specific Data Block) of the EDID.
Software Engineer at Raspberry Pi Trading. Views expressed are still personal views.
I'm not interested in doing contracts for bespoke functionality - please don't ask.

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Fri Sep 18, 2020 7:21 am

6by9 wrote:
Fri Sep 18, 2020 6:59 am

HDMI < 2.0 maxes out at 300MHz, and this is described in one part of the EDID.
HDMI >= 2.0 have to support scrambling as a spread spectrum EMC-reduction step, and that is described in the HF-VSDB (HDMI Forum Vendor Specific Data Block) of the EDID.
Thanks - so i think that is saying that what I quoted isn't of relevance here?

I have a different micro hdmi cable on order and will try that a a next step.

jamest
Posts: 9
Joined: Sat Sep 12, 2020 7:36 am

Re: Pi4 4k 60hz issue

Mon Sep 21, 2020 2:29 am

No luck with the new micro HDMI cable unfortunately. Unfortunately I don't have another 4k display or another pi 4 to swap out. Sounds like I'm out of options to get this to work.

Invi..A
Posts: 1
Joined: Thu Oct 01, 2020 2:52 pm

Re: Pi4 4k 60hz issue

Thu Oct 01, 2020 3:18 pm

Here's my cofnig.txt:

# For more options and information see
# http://rpf.io/configtxt
# Some settings may impact device functionality. See link above for details

# uncomment if you get no picture on HDMI for a default "safe" mode
#hdmi_safe=1

# uncomment this if your display has a black border of unused pixels visible
# and your display can output without overscan
disable_overscan=1

# uncomment the following to adjust overscan. Use positive numbers if console
# goes off screen, and negative if there is too much border
#overscan_left=16
#overscan_right=16
#overscan_top=16
#overscan_bottom=16

# uncomment to force a console size. By default it will be display's size minus
# overscan.
#framebuffer_width=1280
#framebuffer_height=720

# uncomment if hdmi display is not detected and composite is being output
#hdmi_force_hotplug=1

# uncomment to force a specific HDMI mode (this will force VGA)
hdmi_group=1
hdmi_mode=97

# uncomment to force a HDMI mode rather than DVI. This can make audio work in
# DMT (computer monitor) modes
#hdmi_drive=2

# uncomment to increase signal to HDMI, if you have interference, blanking, or
# no display
#config_hdmi_boost=4

# uncomment for composite PAL
#sdtv_mode=2

#uncomment to overclock the arm. 700 MHz is the default.
#arm_freq=800

# Uncomment some or all of these to enable the optional hardware interfaces
#dtparam=i2c_arm=on
#dtparam=i2s=on
#dtparam=spi=on

# Uncomment this to enable infrared communication.
#dtoverlay=gpio-ir,gpio_pin=17
#dtoverlay=gpio-ir-tx,gpio_pin=18

# Additional overlays and parameters are documented /boot/overlays/README

# Enable audio (loads snd_bcm2835)
dtparam=audio=on

[pi4]
# Enable DRM VC4 V3D driver on top of the dispmanx display stack
#dtoverlay=vc4-fkms-v3d
#max_framebuffers=2


[all]
#dtoverlay=vc4-fkms-v3d
hdmi_enable_4kp60=1

#hdmi_group=1
#hdmi_mode=97

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