topic Re: i.MX6 Android dual display resolution issue in i.MX Processors

i.MX6 Android dual display resolution issue

kirangv — Tue, 02 May 2017 09:37:23 GMT

Hello,

I am working on "iMX6Q SABRE-AI" running "Android Marshmallow" with dual display(HDMI and LVDS).

I am having resolution issue on both HDMI and LVDS displays.

Bootargs >

-------------

setenv bootargs console=ttymxc3,115200 androidboot.console=ttymxc3 consoleblank=0 vmalloc=320M init=/init video=mxcfb0:dev=ldb,bpp=32 video=mxcfb1:dev=hdmi,1920x1080M@60,bpp=32 video=mxcfb2:off video=mxcfb3:off androidboot.hardware=freescale cma=384M androidboot.selinux=disabled androidboot.dm_verity=disabled

HDMI display (black) is not using the entire screen width where as LVDS display (white) does not show the control buttons.

Please help me on correcting the resolution for both the imx-6 display‌##

Re: i.MX6 Android dual display resolution issue

Bio_TICFSL — Tue, 02 May 2017 15:50:49 GMT

Hi Kiran,

Your Bootargs looks correct!, Apparently you have cloned displays with different display support resolution (for example, LVDS display at 720p and HDMI monitor at 1080p), both will be set to the lower resolution (typically, the LVDS display resolution) although manually setting the resolution on the FB driver. If you want full screen on the HDMI screen, you could try disabling the LVDS display and only sending the video to the HDMI interface. If you want to force the resolution, you could try using ADB commands for manually changing it on this way.

Regards

Re: i.MX6 Android dual display resolution issue

kirangv — Wed, 03 May 2017 13:19:13 GMT

Thank you for the input.

Actually I wanted both HDMI and LVDS display to be up at the same time.

I am able to correct the resolution issue by doing the following :

Max resolution of our LVDS is "1024x600".

So I have edited the file "kernel_imx/arch/arm/boot/dts/imx6qdl_sabreauto.dtsi" and modified vactive value to 600.

---------------------------------------------------------------------------------------------------------------------------------------------------------

&ldb {

status = "okay";

lvds-channel@0 {

fsl,data-mapping = "spwg";

fsl,data-width = <18>;

status = "okay";

display-timings {

native-mode = <&timing0>;

timing0: hsd100pxn1 {

clock-frequency = <65000000>;

hactive = <1024>;

vactive = <600>;

hback-porch = <220>;

hfront-porch = <40>;

vback-porch = <21>;

vfront-porch = <7>;

hsync-len = <60>;

vsync-len = <10>;

};

---------------------------------------------------------------------------------------------------------------------------------------------------------

We got help from following link : https://community.nxp.com/thread/373763

Thanks,

Kiran