How to set overscan in linux

nowplay · October 2, 2019, 2:29am

when I boot ubuntu Linux , for corner can not display .
I think I should adjust the overscan .

hyphop · October 2, 2019, 2:43am

a u sure its not display problem ?
some tv display make rescaling ! plz check setting and try to change it to pixel 1:1 just scan

nowplay · October 2, 2019, 6:14am

in some tv,ex,sony,can work.
but not work in sharp

Yasir_Javed · April 20, 2021, 4:50pm

@hyphop @Gouwa

I am having issue of overscan when connect with tv. All borders are little bit cropped.

I have checked and my tv has 16:9, 4:3 and Just Scan and Point to Point, but in all cases the screen crop is not fixed.

I have tried xrandr command using archwiki tips but didn’t work… I’m using manjaro Linux on emmc and armbian twister on sdcard and both have same issue.

Can you help how i can try to fix it?

I tried your recommendation in another thread as below:

root@Khadas:~# echo 10 10 1909 1069 > /sys/class/graphics/fb0/window_axis
root@Khadas:~# echo 0x10001 > /sys/class/graphics/fb0/free_scale

but running each command gives this error “bash: /sys/class/graphics/fb0/window_axis: Permission denied”

@Spikerguy

Yasir_Javed · April 22, 2021, 4:27am

Team, @hyphop @Spikerguy @Gouwa

Can i get some help regarding this?

Thanks

Yasir_Javed · April 22, 2021, 2:51pm

Anyone??? I would really appreciate anything here. Having lot of trouble setting this up with my main tv which is my primary display for vim

hyphop · April 24, 2021, 12:35pm

1st - which kernel version ?!

Yasir_Javed · April 24, 2021, 1:16pm

Hi @hyphop

Linux-vim, 5.11.7…it’s the default mainline kernel of latest manjaro…

My current setup info is :
Linux yasirvim 5.11.7-1-MANJARO-ARM #1 SMP PREEMPT Mon Mar 22 20:22:09 +03 2021 aarch64 GNU/Linux

My problem is the borders are little bit cut on all sides

Please note that I have tried all TV ZOOM options like 4:3, 16:9, zoom1, zoom2, POINT - TO - POINT, panorama, JUST SCAN etc but the problem is not fixed

I need some software solution like output scaling using xrandr or other display driver parameters…

Edit : same problem in khadas Ubuntu mainline running from SD and kernel 5.7

Yasir_Javed · April 25, 2021, 8:34am

Update : RESOLVED

Using kernel 4.9 emmc Ubuntu image, the instructions below worked

root@Khadas:~# echo 30 30 1889 1049 > /sys/class/graphics/fb0/window_axis
root@Khadas:~# echo 0x10001 > /sys/class/graphics/fb0/free_scale

See below :

This means it’s an issue with mainline kernel and panfrost probably… 4.9 legacy is fine.

Thanks @numbqq @hyphop @Gouwa

Yasir_Javed · April 27, 2021, 8:22pm

@numbqq

Is there any plan to bring this feature in mainline kernel? Right now the 5.11 kernel does not have window_axis and free_scale variables in sys/class /graphics /fb0 /

numbqq · April 28, 2021, 1:11am

The mainline kernel driver is totally different from 4.9 kernel, so they won’t be there.

Yasir_Javed · April 28, 2021, 1:17am

So do you have any other advice for fixing overscan on mainline?

I have tried many things through xrandr but they don’t work. The only thing that worked 100% was the echo to window_axis and free_scale but these are only available in khadas 4.9 kernel and not available in mainline.

I use my vim with a tv which unfortunately does not have overscan adjustment.

numbqq · April 28, 2021, 2:05am

Have you checked xrandr --output HDMI1 --transform ?

e.g.

$ xrandr --output HDMI1 --transform 0.80,0,-35,0,1.04,-19,0,0,1

For more information, please check the documentation below:

https://wiki.archlinux.org/index.php/Xrandr#Correction_of_overscan_tv_resolutions_via_--transform

Yasir_Javed · May 2, 2021, 5:39am

I think this is working… I used it today and image adjusted somehow within the TV frame. I think I will need to tweak the values, but it worked this time.

BEFORE

AFTER

LATEST PROGRESS (everything is now visible, but some black bars still there)

Setting for above

Thanks @numbqq