mpc8309 flexcan resister's space can not access

[databus]

I have a mpc8309 board，the version of uboot is "uboot 2010.06".But i can not access the flexcan registers,when i access flexcan registers,there is a "Machine check exception",and i do not know why.Uboot set the IMMR register value 0xe0000000.Please help me ......

[r8070z]

I do not see did you try to read IMMR itself? What did return “md  0xe00000000  1”? Notice the memory mapped registers are includes reserved spaces. For example at offset 0xc the CAN memory map shows reserved 4 bytes. Reading from address locations which appear as reserved in the memory map table is not guaranteed to return predictable data.

[databus]

This problem have been solved.CAN1_SUP_EN bit of Access Control Register(CAN_DBG_CTRL register)must set 1 before access CAN register space.