Fujitsu Fujitsu SPARC64 V manual D1 Cache Way Reduction, U2 Cache Way Reduction

Models: Fujitsu SPARC64 V

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2.Otherwise:

All entries in I1 cache way W are invalidated and the way W will never be refilled.

The restrainable error ASI_AFSR.DG_L1$U2$STLB is reported to software.

D1 Cache Way Reduction

When a way reduction condition is recognized for the D1 cache way W (W = 0 or 1), the following way reduction procedure is executed:

1.When only one way in D1 cache is active because of previous way reduction:

The CPU enters error_state.

2.Otherwise:

All entries in D1 cache way W are invalidated and the way W will never be refilled. On invalidation of each dirty D1 cache entry, the D1 cache line is written back to its corresponding U2 cache line.

The restrainable error ASI_AFSR.DG_L1$U2$STLB is reported to software.

U2 Cache Way Reduction

When a way reduction condition is recognized for a U2 cache way, the U2 cache way reduction procedure is executed as follows:

1.When ASI_L2CTL.WEAK_SPCA = 0,

the U2 cache way reduction procedure (below) is started immediately.

2.Otherwise, when ASI_L2CTL.WEAK_SPCA = 1 is set,

the U2 cache way reduction procedure (below) becomes pending until

ASI_L2CTL.WEAK_SPCA is changed to 0. When ASI_L2CTL.WEAK_SPCA is changed to 0, the U2 cache way reduction procedure will be started.

The U2 cache way W (W=0, 1, 2, or 3) reduction procedure:

1.When only one way in U2 cache is active because of previous way reductions:

All entries in U2 cache way W are at once invalidated (that is, all active U2 cache entries are invalidated) and U2 cache way W remains as the only available U2 cache way. The U2 cache data is invalidated to retain system consistency.

The restrainable error ASI_AFSR.DG_L1$U2$STLB

though the available U2 cache configuration is error.

is reported to software, even not changed as a result of the

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

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Fujitsu Fujitsu SPARC64 V manual D1 Cache Way Reduction, U2 Cache Way Reduction