Level 2 Memory System
ARM DDI 0500D
Copyright © 2013-2014 ARM. All rights reserved.
7-2
ID021414
Non-Confidential
7.1
About the L2 memory system
The L2 memory system consists of an:
•
Integrated
Snoop Control Unit
(SCU), connecting up to four cores within a cluster. The
SCU also has duplicate copies of the L1 Data cache tags for coherency support. The L2
memory system interfaces to the external memory system with either an AMBA 4 ACE
bus or an AMBA 5 CHI bus. All bus interfaces are 128-bits wide.
•
Optional tightly-coupled L2 cache that includes:
—
Configurable L2 cache size of 128KB, 256KB, 512KB, 1MB and 2MB.
—
Fixed line length of 64 bytes.
—
Physically indexed and tagged cache.
—
16-way set-associative cache structure.
—
Optional ACP interface if an L2 cache is configured.
—
Optional ECC protection.
The L2 memory system has a synchronous abort mechanism and an asynchronous abort
mechanism, see
External aborts handling
on page 7-18
.