Firefly Open Source Community

   Login   |   Register   |
New_Topic
12
New Topic
Print Previous Topic Next Topic

RK3399 DisplaPort no 4K resolution

8

Credits

0

Prestige

0

Contribution

new registration

Rank: 1

Credits
8
Posted at 4/3/2018 17:11:51        Only Author  11#

RE: RK3399 DisplaPort no 4K resolution

Last edited by Markie In 4/4/2018 14:23 Editor

Dear all,

additional info below (edit 2018-04-04)

I too try to get a DisplayPort 4K monitor  (AOC U2879VF) working, however no success yet.
I have modified the DTS-file accordingly, and I see a couple of things:

1) 'dumpsys SurfaceFlinger' shows 2 displays: "Built-in screen" and "HDMI screen". The latter is the the DisplayPort 4K monitor. The naming is hardcoded in the Android source, and reading the EDID shows it is the correct monitor (and I have no display connected via HDMI). Only one monitor via HDMI shows only "Built-in screen". I don't think this is an issue, as Android tries to clone to each video output.

2) I guess the VOP_LITTLE seems to be selected for DisplayPort output (and not the VOP_BIG), as the current mode is 2560x1440@60p and the modes list does not contain above this (also not 3840x2160p60), while the monitor is capable.
  1. $cat /sys/devices/platform/display-subsystem/drm/card0/card0-DP-1/modes
  2. 2560x1440p60
  3. 1920x1080p60
  4. 1920x1080p60
  5. 1920x1080p60
  6. ...
Copy the code
3) Although the monitor should accept 2560x1440@60p, there is no image on the monitor and I get the following dmesg/console-output when connecting the monitor:
  1. [   13.220928] fusb302 4-0022: attention, dp_status a
  2. [   13.227559] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected without sink. Assert hpd
  3. [   13.287002] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected, not enabled. Enabling cdn
  4. [   14.239036] fusb302 4-0022: attention, dp_status 8a
  5. [   14.241816] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  6. [   57.438951] fusb302 4-0022: attention, dp_status 18a
  7. [   57.444952] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  8. [   69.396299] fusb302 4-0022: attention, dp_status 18a
  9. [   69.402256] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  10. [   71.460755] fusb302 4-0022: attention, dp_status 18a
  11. [   71.467507] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  12. [   72.984966] fusb302 4-0022: attention, dp_status 18a
  13. [   72.992195] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  14. [   96.583813] fusb302 4-0022: attention, dp_status a
  15. [   96.591843] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  16. [   97.572369] fusb302 4-0022: attention, dp_status 8a
  17. [   97.579922] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
  18. [  138.177425] fusb302 4-0022: attention, dp_status 18a
  19. [  138.185544] cdn-dp fec00000.dp: [drm:cdn_dp_pd_event_work] Connected with sink. Re-train link
Copy the code
Resulting in some questions:
1) How can I verify which VOP is "used" for which display?
2) How to make sure VOP_BIG is "used"?
3) Do you have any information about this "dp_status 18a"? Maybe to suspect the monitor ...

additional info: I see a difference between boards, as I have boards with different production dates/stickers
- one board with production date 2017-08-22: see above observations
- one board with production date 2018-03-29: works out of the box! (although only 2560x1440@60p, and not yet 3840x2160@60p)
I don't know whether there is a hardware change, or it is subject to hardware component variations, ...

Thanks in advance,
With kind regards, Mark
Reply

Use props Report

26

Credits

0

Prestige

0

Contribution

new registration

Rank: 1

Credits
26
Posted at 4/27/2018 15:09:35        Only Author  12#
Dear Team-Firefly,
we still need the 4k@60Hz DP output.

Can you please provide a firmware image which makes the board work as advertised?

Thanks!
BR
fl0wtec
Reply

Use props Report

792

Credits

10

Prestige

10

Contribution

advanced

Rank: 4

Credits
792
Posted at 5/5/2018 16:45:21        Only Author  13#
iltis-wiesel Posted at 4/27/2018 15:09
Dear Team-Firefly,
we still need the 4k@60Hz DP output.

modif code like #6 said .
If cannot up to the 4K but better than 1080p, it might be speed limited by cable.
Reply

Use props Report

66

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
66
Posted at 5/21/2019 21:10:14        Only Author  14#
Hi fl0wtec,

Did you ever manage to resolve the USBC(DP) VGA screen resolution list issue?
Reply

Use props Report

128

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
128
Posted at 1/9/2026 11:07:26        Only Author  15#
Alle wünschen sich Erfolg. Die im IT-Bereich arbeitende Leute wissen sicherlich die Wichtigkeit der Zertifizierung der Palo Alto Networks XSIAM-Analyst für die Karriere. Immer mehr Leute nehmen an der Palo Alto Networks XSIAM-Analyst Prüfung teil. Wie kann man beim immer schweren Wettbewerb noch siegen? Den richtigen Hilfspartner auszuwählen ist am wichtigsten. PrüfungFrage hat die Palo Alto Networks XSIAM-Analyst Prüfung schon mehrere Jahre geforscht. Wir haben gute Kenntnisse in dieser Prüfung. Mit Hilfe der Palo Alto Networks XSIAM-Analyst Prüfungssoftware von uns wird Ihr Sieg bei der Prüfung gesichert.
Reply

Use props Report

132

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
132
Posted at 1/28/2026 20:33:10        Only Author  16#
What a powerful piece, thank you for sharing this inspiring article! Here are the Valid CIS-PA exam question materials, free of charge—best of luck!
Reply

Use props Report

137

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
137
Posted at 2/12/2026 13:22:44        Only Author  17#
Cyber ABのCMMC-CCP認定試験に合格することはきっと君の職業生涯の輝い将来に大変役に立ちます。Xhs1991を選ぶなら、君がCyber ABのCMMC-CCP認定試験に合格するということできっと喜んでいます。Xhs1991のCyber ABのCMMC-CCP問題集を購入するなら、君がCyber ABのCMMC-CCP認定試験に合格する率は100パーセントです。あなたはXhs1991の学習教材を購入した後、私たちは一年間で無料更新サービスを提供することができます。
Reply

Use props Report

137

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
137
Posted at 2/14/2026 18:21:22        Only Author  18#
Thank you for your article, it really opened my eyes! The Reliable MS-900 source exam questions are now available for free. Good luck to everyone!
Reply

Use props Report

130

Credits

0

Prestige

0

Contribution

registered members

Rank: 2

Credits
130
Posted at 2/17/2026 20:57:49        Only Author  19#
This article gave me a new perspective, thank you for sharing! Level up your IT skills with free 72201T latest test study guide. Best of luck with everything!
Reply

Use props Report

Return to List
12
You need to log in before you can reply Login | Register

This forum Credits Rules

Quick Reply Back to top Back to list