Host controller TD breaking mechanism

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Hi,

Suppose one TD that has 5 TRBs and each has trb Length of 200 bytes
except last Trb all have chain bit set to 1.
Single TD contains 5 TRBs.

--------------------------------------
|   -------------------------        | 
|   |trnlen =200 chain=1    |  TRB=1 |
|   -------------------------        |   
|   -------------------------        |      
|   |trnlen =200 chain=1    |  TRB=2 |      
|   -------------------------        |      
|   -------------------------        |      
|   |trnlen =200 chain=1    |  TRB=3 |      
|   -------------------------        |      
|   -------------------------        |      
|   |trnlen =200 chain=1    |  TRB=4 |      
|   -------------------------        |     
|   -------------------------        |      
|   |trnlen =200 chain=0    |  TRB=5 |    
|   -------------------------        |   
--------------------------------------

Now in this case XHC should transfer individual TRBs to USB pipe 
or it should wait till the completion of TD and 
then transfer the chunk of data to USB pipe?

Software will ring the doorbell after adding all TRB in TD 
or software can ring the doorbell after loading one TRB of TD
and after that add TRBs simultaneously on Ring?

Thanks,
Nikunj

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