Compaq EV68A Error Case Summary, 3summarizes the various error cases and their ramifications

Models: EV68A

1 356
Download 356 pages 47.63 Kb
Page 238
Image 238

Error Case Summary

8.13 Error Case Summary

Table 8–3summarizes the various error cases and their ramifications.

Table 8–3 Error Case Summary

 

 

 

Hardware

 

Error

Exception

Status

Action

PALcode Action

 

 

 

 

 

Icache data or tag

CRD

ISTAT[PAR]

Icache flushed

Log as CRD

parity error

 

 

 

 

Dcache tag parity

DFAULT

MM_STAT[DC_TAG_PERR]

Evict with two

error (on issue)

 

VA[address]

 

HW_LDs and log as

 

 

 

 

CRD

Dcache tag parity

MCHK1

DC_STAT[TPERR_P0] or

Log as MCHK

error (on retry)

 

DC_STAT[TPERR_P1]

 

 

Dcache single-bit

CRD

DC_STAT[ECC_ERR_LD]

Corrected and

Log as CRD

ECC error on load

 

C_STAT[DSTREAM_DC_ERR]

scrubbed

 

 

 

C_ADDR[bits [19:6] of the error

 

 

 

 

address. [42:20] not updated.]

 

 

Dcache single-bit

CRD

DC_STAT[ECC_ERR_LD]

None

Log as CRD

ECC error on

 

C_STAT contains zero

 

 

speculative load

 

 

 

 

Dcache single-bit

CRD

DC_STAT[ECC_ERR_ST]

Corrected and

Log as CRD

ECC error on small

 

 

scrubbed

 

store

 

 

 

 

Dcache single-bit

None

None

Corrected and

None

ECC error on victim

 

 

scrubbed

 

read

 

 

 

 

Dcache second error

MCHK1

DC_STAT[SEO]

No correction

Log as MCHK

on store

 

 

on either store

 

Dcache duplicate tag

MCHK1

C_STAT[DC_PERR]

Uncorrectable

Log as MCHK

parity error

 

C_ADDR[error address]

 

 

Bcache tag parity

MCHK1

C_STAT[BC_PERR]

Uncorrectable

Log as MCHK

error

 

C_ADDR[error address]

 

 

Bcache single-bit

MCHK

C_STAT[ISTREAM_BC_ERR]

Icache flushed

Scrub error as described

error on Icache fill

and CRD2

C_ADDR[error address]

 

in Section D.36.

 

 

C_SYNDROME_0

 

Log as CRD

 

 

C_SYNDROME_1

 

 

Bcache single-bit

CRD

DC_STAT[ECC_ERR_LD]

Corrected and

Scrub error as described

error on Dcache fill

 

C_STAT[DSTREAM_BC_ERR]

scrubbed in

in Section D.36.

 

 

C_ADDR[error address]

Dcache3

Log as CRD

 

 

C_SYNDROME_0

 

 

 

 

C_SYNDROME_1

 

 

Bcache victim read

CRD

DC_STAT[ECC_ERR_LD]

None

Log as CRD

on Dcache/Bcache

 

C_STAT contains 0

 

 

miss

 

 

 

 

Bcache victim read

None

None

None

None

on ECB

 

 

 

 

8–10Error Detection and Error Handling

21264/EV68A Hardware Reference Manual

Page 238
Image 238
Compaq EV68A specifications Error Case Summary, 3summarizes the various error cases and their ramifications, Section D.36