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The CONFIG_ADDRESS 0x8000f808 does not mean register 02h. It corresponds to register 08h which is RID - Revision Identification Register.
Since the CONFIG_ADDRESS has lower 2 bits [1:0] hardwired to 2'b00 .. this means that you can only access DWORD aligned address.. i.e. 00h, 04h, 08h, 0Ch etc....
This also means that if you need to read any register with address from 00h to 03h, you just provide lower 8 bits of CONFIG_ADDRESS as 00h.. similar for accessing any register with address from 04h to 07h, you need to program CONFIG_ADDRESS lower 8bits [7:0] as 04h and so on...
Can you try reading with address 0x8000f804 and see it if matches with data that is mentioned in the datasheet (which should be 0003h).
Hope this helps.