Fujitsu Fujitsu SPARC64 V Translation Table Entry TTE, Table F-1Organization of SPARC64 V TLBs

Models: Fujitsu SPARC64 V

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The micro-TLBs are coherent to main TLBs and are not visible to software, with the exception of TLB multiple hit detection. Hardware maintains the consistency between micro-TLBs and main TLBs.

No other details on micro-TLB are provided because software cannot execute direct operations to micro-TLB and its configuration is invisible to software.

TABLE F-1Organization of SPARC64 V TLBs

Feature

sITLB and sDTLB

fITLB and fDTLB

 

 

 

Entries

2048

32

Associativity

2-way set associative

Fully associative

Page size supported

8 KB/4MB

8 KB/64 KB/512 KB/4 MB

Locked translation entry

Not supported

Supported

Unlocked translation entry

Supported

Supported

 

 

 

IMPL. DEP. #223: Whether TLB multiple-hit detections are supported in JPS1 is implementation dependent.

On SPARC64 V, TLB multiple hit detection is supported. However, the multiple hit is not detected at every TLB reference. When the micro-TLB (uTLB), which is the cache of sTLB and fTLB, matches the virtual address, the multiple hit in sTLB and fTLB is not detected. The multiple hit is detected only when the micro-TLB mismatches and main TLB is referenced.

F.2 Translation Table Entry (TTE)

IMPL DEP. in Commonality TABLE F-1:TTE_Data bits 46–43 are implementation dependent.

On SPARC64 V, TTE_Data bits 46:43 are reserved.

IMPL. DEP. #224: Physical address width support by the MMU is implementation dependent in JPS1; minimum PA width is 43 bits.

The SPARC64 V MMU implements 43-bit physical addresses. The PA field of the TTE holds a 43-bit physical address. The MMU translates virtual addresses into 43-bit physical addresses. Each cache tag holds bits 42:6 of physical addresses.

Bits 46:43 of each TTE always read as 0 and writes to them are ignored.

A cacheable access for a physical address ≥ 400 0000 000016 always causes the cache miss for the U2 cache and generates a UPA request for the cacheable access. The urgent error ASI_UGESR.SDC is signalled after the UPA cacheable access is requested.

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

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Fujitsu Fujitsu SPARC64 V manual Translation Table Entry TTE, Table F-1Organization of SPARC64 V TLBs