Architecture

CACHE

Cache (cont.)

CACHE

Bits 20..18 of the Cache instruction select the operation to be performed as follows.

 

Bit#

 

Cache

Operation

Description

20

19

18

ID

Name

 

 

 

 

 

 

 

0

0

0

I

IndexInvalidate

Sets the cache state of the cache block to

 

 

 

 

 

Invalid. This instruction is valid only

 

 

 

 

 

when the instruction cache is invalid

 

 

 

 

 

(Config register ICE bit is 0).

0

0

1

D

IndexLRUBitClear

Clears the LRU bit of the cache at the

 

 

 

 

 

designated index.

0

1

0

D

IndexLockBitClear

Clears the Lock bit of the cache at the

 

 

 

 

 

designated index.

1

0

0

D

HitInvalidate

If a cache block contains the designated

 

 

 

 

 

address, sets that cache block to Invalid.

 

 

 

 

 

 

Operation :

T:vAddr ((offset15)16 offset15..0) + GPR[base]

(pAddr, uncached AddressTranslation (vAddr, DATA)

Exceptions :

Coprocessor Unusable exception

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Toshiba TX39 user manual Bit# Cache Operation Description Name