F. A P P E N D I X L

Address Space Identifiers

Every load or store address in a SPARC V9 processor has an 8-bit Address Space Identifier (ASI) appended to the VA. The VA plus the ASI fully specifies the address. For instruction loads and for data loads or stores that do not use the load or store alternate instructions, the ASI is an implicit ASI generated by the hardware. If a load alternate or store alternate instruction is used, the value of the ASI can be specified in the %asi register or as an immediate value in the instruction. In practice, ASIs are not only used to differentiate address spaces but are also used for other functions, such as referencing registers in the MMU unit.

Please refer to Commonality for Sections L.1 and L.2.

L.3 SPARC64 V ASI Assignments

For SPARC64 V, all accesses made with ASI values in the range 0016–7F16when PSTATE.PRIV = 0 cause a privileged_action exception.

Warning – The software should follow the ASI assignments and VA assignments in TABLE L-1. Some illegal ASI or VA accesses will cause the machine to enter unknown states.

TABLE L-1

SPARC64 V ASI Assignments (1 of 3)

 

 

 

 

 

 

 

 

 

 

Value

ASI Name (Suggested Macro Syntax)

Type

VA

Description

Page

 

 

 

 

 

 

0016–3316

(JPS1)

 

 

 

 

3416

ASI_ATOMIC_QUAD_LDD_PHYS

R

 

54

3516–3B16

(JPS1)

 

 

 

 

3C16

ASI_ATOMIC_QUAD_LDD_PHYS_LITTLE

R

 

54

3D16–4416

(JPS1)

 

 

 

 

 

 

 

 

 

 

117

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Fujitsu Fujitsu SPARC64 V manual Address Space Identifiers, SPARC64 V ASI Assignments 1