Command Ring Pointer (CRP) This field defines high order bits of the initial value of the 64-bit Command Ring Dequeue Pointer. Notes: 1. Writes to this field are ignored when Command Ring Running bit (CRR) = 1b. 2. If the CRCR register is written while the Command Ring is stopped (CRR = 0b), the value of this field shall be used to fetch the first Command TRB the next time the Host Controller Doorbell register is written with the DB Reason field set to Host Controller Command. 3. If the CRCR register is not written while the Command Ring is stopped (CRR = 0b), then the Command Ring shall begin fetching Command TRBs at the current value of the internal xHC Command Ring Dequeue Pointer. 4. Reading this field always returns 0b. |