Hello @athul_am
All i.MX 6 supports one CAN with the default device tree on i.MX 6SABRE-AI. Supports both CANs using the FlexCAN device tree but has a pin conflict with FEC. Supports with the default device tree on i.MX 6SoloX-SD, 7Dual SABRE-SD, 6Ultre Lite EVK, and 6ULL EVK. With the platform that supports the FlexCAN module, FlexCAN supports CANFD mode.
Also you can take a look to the table Table 42. FlexCAN Driver Files on IMX Reference Manual.
Also, the i.MX6ULL provides a CAN access through the J1201 port.

Best regards,
Salas.