
8-2
DATA INTEGRITY
8.1.
ERROR CLASSIFICATION
The Pentium Pro architecture uses the following error classification. An implementation may al-
ways choose to report an error in a more severe category to simplify its logic.
•
Recoverable error (RE): The error can be corrected by a retry or by using ECC infor-
mation. The error is logged in the MCA hardware.
•
Unrecoverable error (UE): The error cannot be corrected, but it only affects one agent.
The memory interface logic and bus pipeline are intact, and can be used to report the error
via an exception handler.
•
Fatal error (FE): The error cannot be corrected and may affect more than one agent. The
memory interface logic and bus pipeline integrity may have been violated, and cannot be
reliably used to report the error via an exception handler. A bus pipeline reset is required of
all bus agents before operation can continue. An exception handler may then proceed.
8.2.
PENTIUM
®
PRO PROCESSOR BUS DATA INTEGRITY
ARCHITECTURE
The Pentium Pro processor bus’s major address and data paths are protected by ten check bits,
providing parity or ECC. Eight ECC bits protect the data bus. Single-bit data ECC errors are au-
tomatically corrected. A two-bit parity code protects the address bus. Any address parity error
on the address bus when the request is issued can be optionally retried to attempt a correction.
Two control signal groups are explicitly protected by individual parity bits: RP# and RSP#. Er-
rors on most remaining bus signals can be detected indirectly due to a well-defined bus protocol
specification that enables detection of protocol violation errors. Errors on a few bus signals can-
not be detected without the use of FRC mode.
An agent is not required to support all data integrity features, as each feature is individually en-
abled through the power-on configuration register. See Chapter 9, Configuration of the Pentium
Pro processor EBS 3.0.
8.2.1.
Bus Signals Protected Directly
Most Pentium Pro processor bus signals are protected by parity or ECC. Table 8-1 shows which
signals protect which signals, what phases the protection is valid in, and what effect the address
size (ASZ[1:0]#) has on the protected signals.
Содержание Pentium Pro Family
Страница 17: ...1 Component Introduction ...
Страница 26: ...2 Pentium Pro Processor Architecture Overview ...
Страница 27: ......
Страница 36: ...3 Bus Overview ...
Страница 62: ...4 Bus Protocol ...
Страница 105: ...5 Bus Transactions and Operations ...
Страница 126: ...6 Range Registers ...
Страница 131: ...7 Cache Protocol ...
Страница 135: ...8 Data Integrity ...
Страница 148: ...9 Configuration ...
Страница 161: ...10 Pentium Pro Processor Test Access Port TAP ...
Страница 172: ...11 Electrical Specifications ...
Страница 201: ...12 GTL Interface Specification ...
Страница 229: ...13 3 3V Tolerant Signal Quality Specifications ...
Страница 233: ...14 Thermal Specifications ...
Страница 239: ...15 Mechanical Specifications ...
Страница 241: ...15 2 MECHANICAL SPECIFICATIONS s Figure 15 1 Package Dimensions Bottom View ...
Страница 252: ...16 Tools ...
Страница 260: ...16 8 TOOLS Figure 16 4 Generic MP System Layout for Debug Port Connection ...
Страница 264: ...17 OverDrive Processor Socket Specification ...
Страница 290: ...A Signals Reference ...
Страница 320: ...Index ...
Страница 328: ......