Compaq 21264 Network Card User Manual


 
8–10 Error Detection and Error Handling
21264/EV68A Hardware Reference Manual
Error Case Summary
8.13 Error Case Summary
Table 8–3 summarizes the various error cases and their ramifications.
Table 8–3 Error Case Summary
Error Exception Status
Hardware
Action PALcode Action
Icache data or tag
parity error
CRD ISTAT[PAR] Icache flushed Log as CRD
Dcache tag parity
error (on issue)
DFAULT MM_STAT[DC_TAG_PERR]
VA[address]
Evict with two
HW_LDs and log as
CRD
Dcache tag parity
error (on retry)
MCHK
1
DC_STAT[TPERR_P0] or
DC_STAT[TPERR_P1]
—LogasMCHK
Dcache single-bit
ECC error on load
CRD DC_STAT[ECC_ERR_LD]
C_STAT[DSTREAM_DC_ERR]
C_ADDR[bits [19:6] of the error
address. [42:20] not updated.]
Corrected and
scrubbed
Log as CRD
Dcache single-bit
ECC error on
speculative load
CRD DC_STAT[ECC_ERR_LD]
C_STAT contains zero
None Log as CRD
Dcache single-bit
ECC error on small
store
CRD DC_STAT[ECC_ERR_ST] Corrected and
scrubbed
Log as CRD
Dcache single-bit
ECC error on victim
read
None None Corrected and
scrubbed
None
Dcache second error
on store
MCHK
1
DC_STAT[SEO] No correction
on either store
Log as MCHK
Dcache duplicate tag
parity error
MCHK
1
C_STAT[DC_PERR]
C_ADDR[error address]
Uncorrectable Log as MCHK
Bcache tag parity
error
MCHK
1
C_STAT[BC_PERR]
C_ADDR[error address]
Uncorrectable Log as MCHK
Bcache single-bit
error on Icache fill
MCHK
and CRD
2
C_STAT[ISTREAM_BC_ERR]
C_ADDR[error address]
C_SYNDROME_0
C_SYNDROME_1
Icache flushed Scrub erroras described
in
Section D.36.
Log as CRD
Bcache single-bit
error on Dcache fill
CRD DC_STAT[ECC_ERR_LD]
C_STAT[DSTREAM_BC_ERR]
C_ADDR[error address]
C_SYNDROME_0
C_SYNDROME_1
Corrected and
scrubbed in
Dcache
3
Scrub error as described
in
Section D.36.
Log as CRD
Bcache victim read
on Dcache/Bcache
miss
CRD DC_STAT[ECC_ERR_LD]
C_STAT contains 0
None Log as CRD
Bcache victim read
on ECB
None None None None