FUJITSU Implementation Supplement Fujitsu SPARC64 V - Manual (Page 205)

194 SPARC JPS1 Implementation Supplement: Fujitsu SPARC64 V • Release 1.0, 1 July 2002
2. Otherwise:
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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 is reported to software, even
though the available U2 cache configuration is not changed as a result of the
error.