How to change DSI setting value from DTS

[r.tanaka]

Hi

I would like to customize DSI settings value (resolution, format, pouch etc.).
Therefore, I am planning to change the setting value from DTS.

Is there any document that describes how to change DTS and how to build it?
If it does not exist, I would like to know how to change DTS and build DTS.

The software and hardware used are as follows.
 software : https://github.com/ayufan-pine64/linux-build (xenial-minimal-pine64-bspkernel-0.7.19-118.img.xz)
 hardware : PINE A64+ 1GB

Thank you.

[dkryder]

you want a DTC, device tree compiler, to both compile/de-compile[disassemble]
google device tree compiler

[r.tanaka]

you want a DTC, device tree compiler, to both compile/de-compile[disassemble]
google device tree compiler

Hi dkryder
Thank you for answering.

I changed the DSI resolution with compile / de-compile.


Changed from default value as follows.
Then, a kernel panic will now occur on startup.

<default>
---------------------------------------------
2166             lcd_x = <0x400>;
2167             lcd_y = <0x258>;
---------------------------------------------
<modify>
---------------------------------------------
2166             lcd_x = <0x216>;
2167             lcd_y = <0x4B0>;
---------------------------------------------

However, setting it to half of the default value starts normally.

<default>
---------------------------------------------
2166             lcd_x = <0x400>;
2167             lcd_y = <0x258>;
---------------------------------------------
<modify>
---------------------------------------------
2166             lcd_x = <0x200>;
2167             lcd_y = <0x12C>;
---------------------------------------------

Is there a limit to the setting value of DSI？

Thank you.

[dkryder]

you probably want to stay with accepted display resolutions of that time and for that chip. 1024x600 [default] is WSVGA. 512X300 is probably a lesser known VGA. i suggest looking at tech reference or datasheet for chips on the pine64, the A64+ allwinner and mali 400 to get an idea of what display resolutions are possible and then modify based on that info. for the most part you can not get them to do anything they were not designed to do.

[r.tanaka]

you probably want to stay with accepted display resolutions of that time  and for that chip. 1024x600 [default] is WSVGA. 512X300 is probably a lesser known VGA. i suggest looking at tech reference or datasheet for chips on the pine64, the A64+ allwinner and mali 400 to get an idea of what display resolutions are possible and then modify based on that info. for the most part you can not get them to do anything they were not designed to do.

Hi dkryder

I have reviewed the following reference manual.
・http://synfare.com/599N105E/hwdocs/pine64/Allwinner_A64_User_Manual_V1.0.pdf
・http://files.pine64.org/doc/datasheet/pine64/A64_Datasheet_V1.1.pdf
・http://synfare.com/599N105E/hwdocs/pine64/index.html

There was no explanation about the resolution of DSI.

[dkryder]

apparently you did not either read them or comprehend them well but the documents do explain what display resolutions are possible on the board and it is up to you to give valid resolutions in the build compile, you can not just change numbers as you please and it may occur for some reason that a valid resolution does not compile for a reason that you will have to research further.

[r.tanaka]

apparently you did not either read them or comprehend them well but the documents do explain what display resolutions are possible on the board and it is up to you to give valid resolutions in the build compile, you can not just change numbers as you please and it may occur for some reason that a valid resolution does not compile for a reason that you will have to research further.

hi dkryder

What documentation describes the supported resolutions?

Or if you know the supported resolutions, please let me know.

Thank you.

[dkryder]

look at page 65
2.1.5.2 Display Output of
http://synfare.com/599N105E/hwdocs/pine6...l_V1.0.pdf

and then actually spend the time reading the other documents listed if you need additional information.

[r.tanaka]

look at page 65
2.1.5.2 Display Output of
http://synfare.com/599N105E/hwdocs/pine6...l_V1.0.pdf

and then actually spend the time reading the other documents listed if you need additional information.

hi dkryder

It is described as "Support 4-lanes MIPI DSI up to 1920x1200@60fps"
It can be read that there is no problem if the resolution is up to 1920x1200.


Thank you.