TMS320F28P650DK: SCI pins confrimations when selecting Bootdef 0x01

Part Number: TMS320F28P650DK

Tool/software:

Hi  Everybody , 

I want to boot and wait for SCI  ,  I m in  256 BGA package 

now  BOOT DEF  set to 0x01  ( wait on SCI ) ,  and so  GPIO 12 and GPIO13  must be  the TX and RX  for SCI  

now question  :  if I look to table 14-7 in TRM  ( latest on web )   "GPIO MUXED PINS"  I Can see that at reset    GPIO12 and 13 are EPWM7 a and b    -->  so HOW they can be SCI TX and RX for boot ?

i m expeting you need to enter and configure GPIOs  before moving away to be ePWM  

can you help me ?

thank you 

BR
Carlo