AM3359: ROM boot sequence

Hello Community , 

I work on 32 bit Microcontrollers and found it little hard to understand AM335X reset sequences. 

1) From the TRM page number 4098 , "Rom Memory map ", it starts from 0x20000 to 0x2bFFF, 

2) but the memory map @ page number 155 , says that boot ROM code range is 0x4000_0000 to 0x4001_FFFF 

i really dont understand these differences. can any one please help to understand 1) and 2)

Also after reset PC is loaded with what address ? how control comes to the RBL code ?

Thanks in advance. 

Kiran