Fujitsu Fujitsu SPARC64 V manual Faults and Traps, TLB miss 64 16-67

Models: Fujitsu SPARC64 V

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8K_POINTER = TSB_Extension[63:14+N]

0000

0 (VA[21+N:13] TSB_Hash)

64K_POINTER = TSB_Extension[63:14+N]

TSB_Hash) 0000

1

(VA[24+N:16]

Value of TSB_Hash for both a shared TSB and a split TSB

When 0 <= N <= 4,

TSB_Hash = context_register[N+8:0]

Otherwise, when 5 <= N <= 15,

TSB_Hash[ 12:0 ] = context_register[ 12:0 ]

TSB_Hash[ N+8:13 ] = 0 ( N-4 bits zero )

F.5 Faults and Traps

IMPL. DEP. #230: The cause of a data_access_exception trap is implementation dependent in JPS1, but there are several mandatory causes of data_access_exception trap.

SPARC64 V signals a data_access_exception for the causes, as defined in F.5 in Commonality. However, caution is needed to deal with an invalid ASI. See Section F.10.9 for details.

IMPL. DEP. #237: Whether the fault status and/or address (DSFSR/DSFAR) are captured when mem_address_not_aligned is generated during a JMPL or RETURN instruction is implementation dependent.

On SPARC64 V, the fault status and address (DSFSR/DSFAR) are not captured when a mem_address_not_aligned exception is generated during a JMPL or RETURN instruction.

Additional information: On SPARC64 V, the two precise traps—

instruction_access_error and data_access_error—are recorded by the MMU in addition to those in TABLE F-2 of Commonality. A modification (the two traps are added) of that table is shown below.

TABLE F-2MMU Trap Types, Causes, and Stored State Register Update Policy

 

 

 

 

Registers Updated

 

 

 

(Stored State in MMU)

 

 

 

I-MMU

 

D-MMU

 

 

 

Tag

D-SFSR,

Tag

Ref #Trap Name

Trap Cause

I-SFSR

Access

SFAR

Access Trap Type

 

 

 

 

 

 

1. fast_instruction_access_MMU_miss

I-TLB miss

X2

X

 

6416–6716

Release 1.0, 1 July 2002

F. Chapter F Memory Management Unit 89

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Fujitsu Fujitsu SPARC64 V manual Faults and Traps, TLB miss 64 16-67