16bit rgba4444 format support in SDL

I’m quite new to linux and SDL. I’m able to run my simple SDL applications
but I have an issue with colors. On the reference board, the video format
supported is RGB 565 and I get the colors correcly but when I run the same
set of libraries and application on customer target, there is an issue with
color because it supports rgba4444 in 16bit formats. The underlying video
driver is fbcon and it opens /dev/fb0. If I direclty write rgba4444 16bit
data without SDL support the video is fine.
I haven’t figured out how to get 16bit rgba4444 enabled. Can anyone give
some idea ?

Thanks in advance
Sanu Mathews