When I am setting vidargs for ldb driver in uboot then the kernel won't load and if I tried without ldb then kernel is booting properly.So what will be the issue?

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When I am setting vidargs for ldb driver in uboot then the kernel won’t boot it stuck at starting kernel message and if I tried without ldb driver then kernel is booting properly in this case display showing some garbage contain that because of I am not providing ldb driver. So what will be the issue?

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hi @Hitesh

Could you provide the software version of your module? Which carrier board are you using?
Did you made any changes to the kernel or devicetree or are you using a regular Bsp release from Toradex?

When I am setting vidargs for ldb driver in uboot then the kernel won’t boot it stuck at starting kernel message

What exactly did you set for vidargs?

I tried without ldb driver then kernel is booting properly in this case display showing some garbage contain that because of I am not providing ldb driver.

Which display and which ldb driver are you using? Could you provide a datasheet of the display?

Best regards, Jaski

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Could you provide the software version of your module? Which carrier board are you using?
I am using imx6q-apalis image 2.8b5 with Qt and customize carrier board which is verified by Toradex bangalore,India .

Did you made any changes to the kernel or devicetree or are you using a regular Bsp release from Toradex?
I have enabled framebuffer in kernel & in devicetree only changed the display frequency parameter according to datasheet.
Last week I was at your Toradex office bangalore,India they build file system for us with Qt compatibility that time Display is working but with some correct content and some garbage content.

What exactly did you set for vidargs?
setenv vidargs ‘video=mxcfb0:dev=ldb,800x600M@63,if=RGB666,video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off fbmem=32M’

Which display and which ldb driver are you using? Could you provide a datasheet of the display?
Please find attached Display datasheet. I am using predifined ldb driver(mxc frame buffer in kernel).link text

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hi @Hitesh

Thanks for this Information. Could you provide the kernel and device tree? The kernel config file would be also very helpful.

Best regards, Jaski

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Device Treelink text

where I can get kernel Config file I am new to this things.

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Hi @Hitesh

These are the device tree files. I need the zImage file and .config file, which are in the folder where you compiled the kernel and devicetree.

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Zimage-[link text][1]
&
local.conf
[1]: https://share.toradex.com/al8v5gx3kajbzg6?direct

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hi @Hitesh

Thanks for these files, I tried a Bsp 2.8b5 Image with your kernel. It seems that you missed ldb=sin0 in the vidargs variable. Try this command for setting vidargs in U-Boot:

setenv vidargs video=mxcfb0:dev=ldb,800x600M@63,if=RGB666 ldb=sin0,video=mxcfb1:off video=mxcfb2:off video=mxcfb3:off fbmem=32M

Best regards, Jaski

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Thank you @jaski.tx
Now kernel is properly booting may I know what is the meaning of this ldb=sin0 & previously I am not using this parameter still everything is working properly.

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Hi

sin/dul/sep where command line arguments on older kernels to configure the LVDS mode used. See also here.

I do not think that stating them on the command line no longer has an effect. Setting the LVDS mode is in the current 4.9. kernel set in the device tree.

The change which was important was replacing the comma between the first and second video=xxxxx parameter with a space.

Max