LOGO issue fix for custom yocto distribution

Looking for an experienced embedded Linux developer to help with the issue. The devices uses raspberry pi 3B+ and a TFT LCD in RGB mode as display and I run Qt’s distribution (b2qt) on it. When I enabled the logo support in Linux, no LOGO is displayed during kernel boot through TFT LCD. Moreover, the rainbow test does not show even though splash is not disabled. (but it worked on HDMI).