JAJSQ97J may 2009 – january 2021 XIO2001
PRODUCTION DATA
The auto pre-fetch agent is an internal logic module that will generate speculative read requests on behalf of a PCI master to improve upstream memory read performance.
The auto pre-fetch agent will generate a read thread on the PCI-express bus when it receives an upstream prefetchable memory read request on the PCI bus. A read thread is a sequence of one or more read requests with contiguous read addresses. The first read of thread will be started by a master on the PCI bus requesting a read that is forwarded to the root complex by the bridge. Each subsequent read in the thread will be initiated by the auto pre-fetch agent. Each subsequent read will use the address that immediately follows the last address of data in the previous read of the thread. Each read request in the thread will be assigned to an upstream request processor. The pre-fetch agent can issue reads for two threads at one time, alternating between the threads.