i.MX ProcessorsのトピックSetting fb other than fb0 as a primary

Setting fb other than fb0 as a primary

ambika — Mon, 06 Feb 2017 07:23:52 GMT

Hii,

I'm working on imx6q processor with yocto dizzy(linux kernel 3.14).

Currently the data is writing to /dev/fb0 and from there to my primary display through the first LVDS channel (LVDS0).

ldb node in dtsi is as below,

...

&ldb {
status = "okay";

lvds-channel@0 {
fsl,data-mapping = "spwg";
fsl,data-width = <18>;
primary;
crtc = "ipu1-di0";
status = "okay";

display-timings {
native-mode = <&timing0>;
timing0: ldb-wvga {
clock-frequency = <33260000>;
hactive = <800>;
vactive = <480>;
hback-porch = <88>;
hfront-porch = <40>;
vback-porch = <33>;
vfront-porch = <10>;
hsync-len = <128>;
vsync-len = <2>;
};
};
};
};

...

From u-boot mxcfb0 tis set to primary display

I assume that currently the data write will be to ipu1_di0 i.e /dev/fb0 and that fb0 is configured to display.

I want to achieve the following,

Write the data to other than ipu1_di0 (if possible to virtual frame buffer) say to fbx.
From fbx to fb0 (on doing some operations like scaling on data in fbx to fb0)

Configuration /dev/fb0 to display is okey.

Please let know the procedure to achieve (1)

Thanks in advance.

Regards,

Ambika

Re: Setting fb other than fb0 as a primary

Bio_TICFSL — Mon, 13 Feb 2017 17:31:11 GMT

Hi Ambika

Please check previuos community thread

How to write a freescale imx6q control fb(framebuffer) program for dual display(L3.10.53 BSP(yocto project))?

iMX6UL: How to change display refresh rate?

Hope this helps

Re: Setting fb other than fb0 as a primary

ambika — Thu, 16 Feb 2017 04:57:56 GMT

hello Bio_TICFSL,

Thanks for the links.

But I want to take the data which is going to the fb0 to virtual frame buffer (fb5) and then do scaling on the data and then send it to fb0.

i.e I want to dump the modified data on my display instead of directly dumping it on the display.

Is there any clue to achieve the same. I'm not able to get where the data is captured to fb0 in my original source code.

Thanks in advance.

Regards,

Ambika