I initialised memory location corresponding to AIPS_A as tlb 4. Does i need to do anything else to get access?
That should be enough. This is default settings of MMU and also we can see that there are no registers for DSPI_C visible at 0xC3F90000:
Then I used this configuration:
lis r3, 0x1004
ori r3, r3, 0x0500
lis r3, 0xC3F0
ori r3, r3, 0x002A
ori r3, r3, 0x003F
(or this script for Lauterbach debugger: MMU.TLB1.SET 4. 0xC0000500 0xC3F0002A 0xC3F0003F)
... and I can see that the registers for DSPI_C are visible and writeable:
No other settings are necessary in this case.
Retrieving data ...