CAN interface enable
CONFIG_CAN_ENABLE
  Say Y here to enable the CAN interace from OpenCores. The core has one
  AHB slave interface for accessing the control registers. The CAN core
  ir register-compatible with the SAJ1000 core from Philips.

CAN register address
CONFIG_CANIO
  The control registers of the CAN core occupy 4 kbyte, and are 
  mapped in the AHB bus I/O area (0xFFF00000 - 0xFFFFF000). This setting
  defines at which address in the I/O area the registers appear (HADDR[19:8]).

CAN interrupt
CONFIG_CANIRQ
  Defines which interrupt number the CAN core will generate.

CAN loob-back testing
CONFIG_CANLOOP
  If you say Y here, the receiver and trasmitter of the CAN core will
  be connected together in a loop-back fashion. This will make it 
  possible to perform loop-back test, but not data will be sent
  or received from the outside. ONLY for testing!

CAN Synchronous reset
CONFIG_CAN_SYNCRST
  If you say Y here, the CAN core will be implemented with
  synchronous reset rather than asynchronous. This is needed
  when the target library does not implement registers with
  async reset. Unless you know what you are doing, say N.

CAN FT memories
CONFIG_CAN_FT
  If you say Y here, the CAN FIFOs will be implemented using
  SEU protected RAM blocks. Only applicable to the FT version
  of grlib.