topic Re: Clone / Mirror Framebuffer in i.MX Processors

Clone / Mirror Framebuffer

chris_ — Thu, 18 Aug 2016 12:50:23 GMT

Hi,

i am using 2 displays, both with a resolution of 1920x1080.

the first is connected via hdmi -> /dev/fb0

the second is using lvds -> /dev/fb2

i am not using any windowing system like x11 or wayland.

is it possible to clone the output from fb0 to fb2?

i already found this thread https://community.nxp.com/thread/318030

but i think its outdated.

thank you

Re: Clone / Mirror Framebuffer

joanxie — Fri, 19 Aug 2016 03:59:22 GMT

yes, mx6 can support dual display, you should add them using uboot command, but if you need to support dual 1080p@60, I don't think IPU can support it, the max pixel rate of IPU is 240MHZ, for more detailed information about IPU, please refer to the Reference Manual.

Re: Clone / Mirror Framebuffer

chris_ — Fri, 19 Aug 2016 07:28:26 GMT

Thank you,

i am currently passing the following video parameters to the kernel:

video=fbmem=24M \

video=mxcfb0:dev=hdmi,1920x1080M@60,bpp=32 \

video=mxcfb1:dev=ldb,LDB-1080P60,if=RGB24,bpp=32 \

but this results in getting two independent framebuffer devices.

i am using a imx6 quad which has two ipus.

but i can also lower the display-resolution if necessary.

i cant find any u-boot command or kernel-parameter for

cloning the displays.

Re: Clone / Mirror Framebuffer

benediktniederm — Wed, 02 Nov 2016 18:55:30 GMT

Hello,

I have also the same question.

I know that it should be possible, because i've already seen, that the same content is displayed simultaneously to HDMI and lvds (cloned).

We have encountered, that there is something different in device tree settings.

Did you found any solution yet?