Hello Aditya Nagal,
You would need to start from one of the two available BSPs, either the Community BSP which is open sourced or the BSP Release (which includes more codecs so perhaps you may want to check this one).
I would keep in mind which board you would want to use. If it’s an NXP board the BSP Release will be available for this board. If it’s a third-party board they may be support on the Community BSP. If it’s a custom board would you need to configure Yocto but I would recommend starting with a similar board and making the necessary changes.
The Community BSP documentation and instructions to for downloading are available on the following link:
http://freescale.github.io/
The BSP Releases are available on NXP website on Downloads under IMXLINUX.
http://www.nxp.com/products/software-and-tools/software-development-tools/i.mx-software-and-tools/em...
Once you have setup Yocto you should be able to build the supported images and customizing them. You may find the following Yocto training interesting:
https://community.nxp.com/docs/DOC-94849
I hope this information helps!
Regards,
