4K HDMI not working with linaro release for DB820c

Products Support DragonBoard 820c
#1

Hello 96board team,

We tested latest release from : http://builds.96boards.org/snapshots/dragonboard820c/linaro/debian/126/
And also snapshot from : http://snapshots.linaro.org/96boards/dragonboard820c/linaro/debian/153/

Details of test setup are as below:
Platform:
DB820c P4/SBC APQ8096(Evaluation Only version)
Downloaded from:
http://builds.96boards.org/snapshots/dragonboard820c/linaro/debian/126/

root@linaro-alip:~# uname -a
Linux linaro-alip 4.11.0-qcomlt #1 SMP PREEMPT Mon Nov 6 23:24:36 UTC 2017 aarch64 GNU/Linux

root@linaro-alip:~# lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux testing (buster)
Release: testing
Codename: buster

root@linaro-alip:~# lsmod
Module Size Used by
venus_enc 24576 0
venus_dec 20480 0
videobuf2_dma_sg 20480 2 venus_dec,venus_enc
videobuf2_memops 16384 1 videobuf2_dma_sg
ath10k_pci 49152 0
venus_core 61440 2 venus_dec,venus_enc
v4l2_mem2mem 24576 3 venus_dec,venus_enc,venus_core
videobuf2_v4l2 24576 3 venus_dec,venus_enc,v4l2_mem2mem
videobuf2_core 45056 5 venus_dec,venus_enc,venus_core,v4l2_mem2mem,videobuf2_v4l2
ip_tables 24576 0
x_tables 40960 1 ip_tables
btrfs 1015808 0
xor 20480 1 btrfs
zlib_deflate 28672 1 btrfs
raid6_pq 106496 1 btrfs

We are not able to get resolution more that 1920x1080@60Hz. We tried below things:

1). Tried changing resolution from GUI(Start=>Preferences=>LXQt settings=>Monitor settings=>Resolution).
>> EDID negotiated to 4K@24-fps
>> Screen goes blue and cosole prints below error:
[ 1132.424330] [drm:mdp5_irq_error_handler] ERROR errors: 40000000
>> Screen again reverts back to 1080p@60-fps

2). We Tried adding /lib/firmware/edid/3840x2160.bin & boot kernel with below parameters
$ fastboot -c ‘root=/dev/sda9 rw rootwait console=ttyMSM0,115200n8 drm_kms_helper.edid_firmware=edid/3840x2160.bin’ boot boot-linaro-buster-dragonboard-820c-126.img
>> Resolution goes to : 1792x1008@60Hz
>> Any other resolution below 1080p works, using above method.
>> 3840x2160.bin generated with “edid-generator” utility and placed at “/lib/firmware/edid/3840x2160.bin” on DB820c
>> content of 3840x2160.S is as below
/* 3840x2160: Modeline “3840x2160” 594.00 3840 4016 4104 4400 2160 2168 2178 2250 +hsync +vsync */
#define HSYNC_POL 1
#define VSYNC_POL 1
#define YPULSE (63+10)
#define XPULSE 88
#define YPIX 2160
#define XPIX 3840
#define VFREQ 60
#define DPI 96
#define CLOCK 594000
#define VERSION 1
#define REVISION 3
#define XOFFSET 176
#define YOFFSET (63+8)
#define XY_RATIO XY_RATIO_16_9
#define YBLANK 90
#define XBLANK 560
#define TIMING_NAME “3840x2160”
#include “edid.S”

3). GPU interrupts & other debugs:
root@linaro-alip:~# glxgears
Error: couldn’t open display (null)
root@linaro-alip:~# cat /proc/interrupts | grep A530
173: 1598 0 0 0 GICv3 332 Level A530

Could you please suggest what is wrong OR is 4K HDMI is working at your end?

Highly appreciate your time & efforts.

How to change HDMI Resolution and Speed
#2

hi,

first, HDMI 4K display is expected to work, and GPU/OpenGL/GLES as well…

This is on my board running #153:

linaro@linaro-alip:~$ xrandr 
Screen 0: minimum 320 x 200, current 3840 x 2160, maximum 65535 x 65535
HDMI-1 connected primary 3840x2160+0+0 (normal left inverted right x axis y axis) 600mm x 340mm
   3840x2160     29.97*   23.98  
   2560x1440     59.95  
   1920x1080     60.00    60.00    59.94    30.00    24.00    29.97    23.98  
   1600x900      60.00  
   1280x1024     60.02  
   1280x800      59.91  
   1152x864      59.97  
   1280x720      60.00    59.94  
   1024x768      60.00  
   800x600       60.32  
   720x480       60.00    59.94  
   640x480       60.00    59.94

Please use builds from Linaro Snapshots now, we no longer update/support the old builds that used to be published on builds.96boards.org.

Please send the complete kernel boot log and the also the content of the Xorg log file. If possible try different monitors as well.

The last error you mention “couldn’t open display” is normal. By default Xorg is started as linaro user, and you are trying to start glxgears with root user. Also you have likely not set DISPLAY variable.

#3

Hello

As an update xrandr & glxgears doesn’t work on serial console or terminal no matter ‘root’ OR ‘linaro’ login.
I have to use ‘XTerm’ from GUI.

Output of xrandr:
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 65535 x 65535
HDMI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 1600mm x 900mm
1920x1080 60.00*+ 50.00 59.94 30.00 25.00 24.00 29.97 23.98
4096x2160 23.98
3840x2160 29.97 23.98
1280x1024 60.02
1360x768 60.02
1152x864 59.97
1280x720 60.00 50.00 59.94
1024x768 60.00
800x600 60.32
720x576 50.00
720x480 60.00 59.94
640x480 60.00 59.94
720x400 70.08

I tried changing resolution with below commands.
$ xrandr --output HDMI-1 --mode 3840x2160
Screen turns BLUE, However EDID is negotiated and Display show 3840x2160@30Hz as expected.

I also tried
$ $ xrandr --output HDMI-1 --mode 4096x2160
again screen turns BLUE.

I have attached X log at:

and kernel boot log at:

#4

I forgot to mention in previous post that now I am using latest release from:
http://snapshots.linaro.org/96boards/dragonboard820c/linaro/debian/153/

Required detail is as below:

root@linaro-alip:~# uname -a
Linux linaro-alip 4.11.0-qcomlt-arm64 #1 SMP PREEMPT Thu Jan 11 19:22:20 UTC 2018 aarch64 GNU/Linux

root@linaro-alip:~# lsb_release -a
No LSB modules are available.
Distributor ID: Debian
Description: Debian GNU/Linux testing (buster)
Release: testing
Codename: buster

root@linaro-alip:~# lsmod
Module Size Used by
joydev 20480 0
venus_dec 20480 0
venus_enc 24576 0
videobuf2_dma_sg 20480 2 venus_dec,venus_enc
videobuf2_memops 16384 1 videobuf2_dma_sg
ath10k_pci 49152 0
venus_core 61440 2 venus_dec,venus_enc
v4l2_mem2mem 24576 3 venus_dec,venus_enc,venus_core
videobuf2_v4l2 24576 3 venus_dec,venus_enc,v4l2_mem2mem
videobuf2_core 45056 5 venus_dec,venus_enc,venus_core,v4l2_mem2mem,videobuf2_v4l2
ip_tables 24576 0
x_tables 40960 1 ip_tables
btrfs 1015808 0
xor 20480 1 btrfs
zlib_deflate 28672 1 btrfs
raid6_pq 106496 1 btrfs

#5

hi,

it could be a display driver issue actually. by any chance , can you try to use this kernel branch? https://github.com/boddob/linux/tree/4.11_db820c_hdmi_fixes_jan2k18 and report if it fixes your issue?