Raspberry pi 4 B 4K 60Hz doesn't work at all

[notisektwo]

I know this topic has been here several times, but I tried everything and nothing led to the result.
The maximum frequency at 4k resolution is 30Hz and nothing can be done about it.
I tried two different HDMI cables, two 4k TVs - both have at least 2.2 HDMI and all HDMI inputs support 60 Hz.
I need to find out if this is a hardware error due to a possible claim for replacement.
In the attachment are:
tvservice -d edid.dat
/boot/config.txt


Thank you for any advice.

[jamesh]

You don't appear to have

Code: Select all

hdmi_enable_4kp60=1

in config.txt. It's commented out.

[notisektwo]

I'm sorry, I played around with config.txt a bit and then I saved it and forgot about this option.
Of course, hdmi_enable_4kp60 = 1 was not commented.
Unfortunately, it's not that simple.

[jamesh]

You are using HDMI 0? 60Hz is not supported on HDMI 1.

[notisektwo]

Yes, of course I read it in the documentation and I connected the TV to HDMI 0.

[notisektwo]

Thanks for your answers, but I tried all these "simple" solutions.
Can you write me how to configure config.txt so that I force RPI video mode 4k 60HZ?
No feedback, so that it is possible to decide if it is a hardware problem.

[jamesh]

Thanks for your answers, but I tried all these "simple" solutions.
Can you write me how to configure config.txt so that I force RPI video mode 4k 60HZ?
No feedback, so that it is possible to decide if it is a hardware problem.

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

hdmi_mode section.

[notisektwo]

In hdmi mode I also tried this:

hdmi_group=1
hdmi_mode=97

Unsuccessfully

Interestingly, if I try to set the resolution in raspi-config A5 resolution,
so nothing happens and raspi-config jump to the previous menu.

[jamesh]

I cannot see how this can be a HW error, but also not sure why it isn't working.

What are exact symptoms - simple the display remaining blank, or complaining about the input signal?

[HiassofT]

Your edid only shows 4:2:0 4k modes at 297MHz pixel clock, the RPi4 doesn't support that format.

Check the settings on your TV, you should find an option named "HDMI ultra deep colour" or something similar like that and enable it. This enables 4:4:4 4k modes at 594MHz pixel clock which are supported just fine on the RPi4.

so long,

Hias

[hanzelpeter]

Hello.

I checked attached edid.dat with edid-decode and found this:

Extended tag: YCbCr 4:2:0 video data block
VIC 96 3840x2160@50Hz
VIC 97 3840x2160@60Hz
VIC 101 4096x2160@50Hz
VIC 102 4096x2160@60Hz

I have also 4k television and see only the same in my edid.dat.
So when I look for "HDMI ultra deep colour" should it affect also edid.dat? Or the RPI will just work on 60hz?

[dickon]

My TV seems to change the EDID on that setting. I get 1080p only without the 4K modes enabled -- exactly what you're seeing.

[jamesh]

So what happening is that the Pi cannot output 4:2:0 YUV. It's uses 4:2:2 which has a higher colour resolution but required twice the bandwidth. I guess cheaper TV's uses this lower colour resolution mode so they don't have to deal with the higher pixel frequencies required for 60Hz 4k with the full colour depth. This is a HW limitation - whether it's at the TV end or the Pi end depends on how you look at it.

[6by9]

So what happening is that the Pi cannot output 4:2:0 YUV. It's uses 4:2:2 which has a higher colour resolution but required twice the bandwidth. I guess cheaper TV's uses this lower colour resolution mode so they don't have to deal with the higher pixel frequencies required for 60Hz 4k with the full colour depth. This is a HW limitation - whether it's at the TV end or the Pi end depends on how you look at it.

Minor correction - it uses RGB 8:8:8. It can support YUV 4:2:2 (and YUV 4:4:4), but that's not the default mode.

[jamesh]

So what happening is that the Pi cannot output 4:2:0 YUV. It's uses 4:2:2 which has a higher colour resolution but required twice the bandwidth. I guess cheaper TV's uses this lower colour resolution mode so they don't have to deal with the higher pixel frequencies required for 60Hz 4k with the full colour depth. This is a HW limitation - whether it's at the TV end or the Pi end depends on how you look at it.

Minor correction - it uses RGB 8:8:8. It can support YUV 4:2:2 (and YUV 4:4:4), but that's not the default mode.

I just KNEW I'd get some detail wrong.

[tvjon]

A 4k TV here which was manufactured in February 2020, I try from time to time to coax into working with RPi4, does support 4:4:4 & 4:2:2 but RPi4 is not prepared to work with it properly - yet.

I have a bug report here:

https://github.com/raspberrypi/linux/issues/3574

Since posting that report, I've updated to:

$ uname -a
Linux b1 5.4.35-v7l+ #1314 SMP Fri May 1 17:47:34 BST 2020 armv7l GNU/Linux

$ vcgencmd version
May 1 2020 17:56:42
Copyright (c) 2012 Broadcom
version 688a8f8f3d84e788f07f53c93693e1705f68c407 (clean) (release) (start_x)

The MMU error still occurs, but additionally, when it "works", any attempt to open a URL via right clicking a hyperlink promptly blanks the screen & I have to unplug & replug the relevant HDMI input to TV, or reboot the TV to get the display back.

If I copy then paste a link into browser, the tv screen seems to carry on ok.

Out of interest I tried:

hdmi_enable_4kp60=1

which seems to reliably make RPi4 think it's a 1920 * 1080p display.

For interest, attached is the decoded edid.dat

[notisektwo]

Thank you for all the contributions.
I tried to turn it on HDMI ultra deep colour
and at the same time set hdmi as PC input.

The good news is that 4K 60Hz works.
The bad news is that USB ports - Mouse, Keyboard is not working.

[bjtheone]

Check the quality of all your cables, as this is likely a RF interference issue. I assume you have a wireless mouse/keyboard with a RF dongle. Adding an extension cable to relocate the dongle away from the Pi helps.

[notisektwo]

I don't know if I have a defective piece. But even HD 1080 from Youtube doesn't play without dropping.
I no longer have the nerve for the waste. I was lured into lies about performance.

[jamesh]

I don't know if I have a defective piece. But even HD 1080 from Youtube doesn't play without dropping.
I no longer have the nerve for the waste. I was lured into lies about performance.

Please post a link to these 'lies'. Extraordinary claims do require evidence. Most people are more than happy with what their $5-$55 Raspberry Pi is capable off.