Fujitsu Fujitsu SPARC64 V manual Secondary Cache and External Access Unit SXU

Models: Fujitsu SPARC64 V

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1.3.5Secondary Cache and External Access Unit (SXU)

The SXU controls the operation of unified level-2 caches and the external data access interface (extended UPA interface). TABLE 1-4describes the major blocks of the SXU.

TABLE 1-4Secondary Cache and External Access Unit Major Blocks

Name

Description

 

 

Unified level-2 cache

2-Mbyte, 4-way associative, 64-byte line, writeback; provides low

 

latency data source for both instruction level-1 cache and data

 

level-1 cache.

Movein buffer

Sixteen entries, 64-bytes/entry; catches returning data from

 

memory system in response to the cache line read request. A

 

maximum of 16 outstanding cache read operations can be issued.

Moveout buffer

Eight entries, 64-bytes/entry; holds writeback data. A maximum

 

of 8 outstanding writeback requests can be issued.

Extended UPA interface

Send/receive transaction packets to/from Extended UPA

control logic

interface connected to the system.

 

 

8 SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002

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Fujitsu Fujitsu SPARC64 V manual Secondary Cache and External Access Unit SXU