Compaq 21264 - Manual (Page 239)

Alpha 21264/EV67 Hardware Reference Manual Error Detection and Error Handling 8–11
Error Case Summary
Bcache double-bit
error on Dcache fill MCHK
1
C_STAT[DSTREAM_BC_DBL]
C_ADDR[error address]
4
None Log as MCHK
Memory double-bit
error on Icache fill MCHK
1
C_STAT[ISTREAM_MEM_DBL]
C_ADDR[error address]
4
None Log as MCHK
Memory double-bit
error on Dcache fill MCHK
1
C_STAT[DSTREAM_MEM_DBL]
C_ADDR[error address]
4
None Log as MCHK
1
Machine check taken in native mode. It is deferred while in PALmode.
2
CRD error posted in case the machine check is down a speculative path.
3
For a single-bit error on a non-target quadword, the error is not corrected in hardware,
but is corrected by PALcode during the scrub operation.
4
The contents of C_ADDR may not be accurate when there is heavy cache fill traffic.
Table 8–3 Error Case Summary (Continued)
Error Exception Status
Hardware
Action
PALcode Action