How to replace jetson nano kernel logo

Hi, I want replace kernel logo , STEPS:
1, pngtopnm logo.PNG | ppmquant -fs 224 | pnmtoplainpnm > logo_linux_clut224.ppm
2.replace kernel_src_build/kernel/kernel-4.9/drivers/video/logo/logo_linux_clut224.ppm
3.logo_lines = DIV_ROUND_UP(logo_height, vc->vc_font.height); replcce to logo_lines = (logo_height)/ vc->vc_font.height;
4.recompile kernel ,and replace Image /boot/Image .

when I reboot ,no any logo ,too.
what is happed?

Hi,
The logo is from bootloader but not kernel. Changing anything on kernel driver will not change the boot logo.

We have some documents in Linux_for_Tegra/tools/bmp-splash. Please check it first.

Thank you for your reply, I had change the bootloade logo. And ,I want add kernel logo, too. But I try my past experiences, It do not work.

We don’t enable the kernel logo.

Maybe other forum users can share their experience…

So…, Is there a way to turn off display initialization in the kernel ? Because there is a splash screen when boot the kernel after bootloader logo.

Do you want the display not showing anything after kernel? I mean even the ubuntu desktop is not needed, just a blanked screen.

Yes, I added my own logo to the bootloader, but when I boot into the kernel, it will flicker and then the screen will go black. After the application system is loaded, my own Qt program will start. I want to remove the splash screen when starting the kernel. It is best to let the bootloader logo display until the file system is loaded.

Hi,

It seems unavoidable. If kernel starts, it means the bootloader has done its own work and gives the monitor to kernel.
Thus, it will be blanked until other applications try to render.

HI, I was wondering if there is a way to skip the initialization of the screen by the kernel and just keep the video memory unchanged? So that my device won’t have the crash screens

Hi,

Does your Qt program need to use the monitor?

yeah. Maybe the method I said doesn’t work. I just want to remove the crash screens.
image
image

Is this screen on your custom carrier board? What interface are you using? HDMI/DP or MIPI DSI?

Is this issue reproducible on nvidia devkit?

Is this screen on your custom carrier board?
-------------Yes.
What interface are you using? HDMI/DP or MIPI DSI?
---------------HDMI
Is this issue reproducible on nvidia devkit?
-------------NO, And I found the backlight is turned off when the kernel is boot.

HI,

Not quite sure what is the exact error. Could you take a video and post it here?

e60643e48f486a0def89d1939bf3fb04.zip (1.1 MB)

Is this a pure system from on jetpack or have you enabled anything in driver?

yes, I just replace my bootloader logo, and flash my device use "sudo ./flash.sh jetson-nano-emmc mmcblk0p1”。

Hi,

This issue should be there even with NV logo case, right?

Could you stop the uboot countdown on serial console and see if that weird block window shows up or not?

This issue should be there even with NV logo case, right?
—>yes.
Could you stop the uboot countdown on serial console and see if that weird block window shows up or not?
----->stop uboot,the window will still my logo。 And ,I think ,that weird block window is shows up because the screen is init by kernel . But, I do not know how to skip it. Perhaps, I have to shutdown backlight when kernel is boot, delay a moment ,then ,turn up backlight again.

Hi,

No, if you stop the uboot and stay at uboot console but still see the block window, then it is not initiated by kernel because uboot has been stopped so kernel has not been initiated…