i.MX ProcessorsのトピックRe: Fb0 data format in imx6dp

Fb0 data format in imx6dp

志林韩 — Thu, 26 Sep 2019 11:29:30 GMT

Hi everyone:

I got problems when getting /dev/fb0 data in imx6dp. I started the demo program Tutorial3_es20, and then I got the data in /dev/fb0 by the following command:dd if=/dev/fb0 of=fbfile. But I can't display it with the player vooya. And I learned that the format in framebuffer has become tiled by adding print.

How should I solve this problem?

Re: Fb0 data format in imx6dp

b36401 — Fri, 27 Sep 2019 04:36:31 GMT

i.MX6 has nothing special regarding to framebuffer format.
You can refer to common Linux documentation:
https://www.kernel.org/doc/Documentation/fb/framebuffer.txt

Re: Fb0 data format in imx6dp

志林韩 — Fri, 27 Sep 2019 06:20:35 GMT

Hi Victor,

When I start the demo tutorial3_es20, the dada format in /dev/fb0 change from IPU_PIX_FMT_BGR32 to IPU_PIX_FMT_GPU32_SRT which is tiled format. So I can't take a screenshot by reading the data in /dev/fb0. This situation only appears on i.MX6dp, In our i.MX6d board, the data format in /dev/fb0 is IPU_PIX_FMT_BGR32.

And I think that it's the prefetch and resolve engine in i.MX6dp affect the format in fb.

BTW: We use the 3.14.52 version of the Linux kernel.

Thanks!

Re: Fb0 data format in imx6dp

b36401 — Thu, 10 Oct 2019 06:49:38 GMT

I can suspect that some change in Linux kernel affected framebuffer format.
Please try to use latest one.