Stratix® 10 Hard Processor System Technical Reference Manual

ID 683222
Date 8/15/2024
Public
Document Table of Contents

4.5.2.2. Speculative Fetch

When the CCU sends a coherent read to the CCC and speculative fetch is enabled, the CCC issues a read to the L2 cache before the coherency directory completes its lookup or sends snoops.

Speculative fetching can reduce the latency of the request but may expend memory bandwidth with unnecessary memory reads. It is recommended that you enable speculative fetch for latency sensitive requests. Disable this feature for requests that are less latency sensitive.

Speculative fetching for the Cortex* -A53 MPCore processor is enabled when the HPS is released from reset. To disable speculative fetch, clear the corresponding bit in the Speculative Fetch register (agent_ccc0_ccc_spec_fetch_0).