Error Detection And Error Handling; Ev67 Error Detection Mechanisms - Compaq 21264 Hardware Reference Manual

This chapter gives an overview of the 21264/EV67 error detection and error handling
mechanisms, and is organized as follows:
•
Data error correction code
•
Icache data or tag parity error
•
Dcache tag parity error
•
Dcache data correctable ECC error
•
Dcache store second error
•
Dcache duplicate tag parity error
•
Bcache tag parity error
•
Bcache data correctable ECC error
•
Memory/system port data correctable ECC error
•
Bcache data correctable ECC error on a probe
•
Double-bit fill errors
•
Error case summary
Table 8–1 summarizes the 21264/EV67 error detection.
Table 8–1 21264/EV67 Error Detection Mechanisms
Component
Bcache tag
Bcache data array
Dcache tag array
Dcache duplicate tag array
Dcache data array
Icache tag array
Icache data array
System port data bus
Alpha 21264/EV67 Hardware Reference Manual

Error Detection and Error Handling

Error Detection Mechanism
Parity protected.
Quadword-ECC protected.
Parity protected.
Parity protected.
Quadword-ECC protected, however this mode of operation is
only supported in systems that have ECC enabled on both the
system and Bcache ports.
Parity protected.
Parity protected.
Quadword-ECC protected.
Error Detection and Error Handling
8
8–1