Link Layer Tests
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Specification Reference
Sections 7.2.4.1.1#6 ● 8,10-17,22 ● 7.2.4.1.4#2 ● 7.3.4#2 ● 7.5.6.1#5,6 ● 8.4.5#1
8.4.6#1,3 (downstream) ● 8.4.7#1 (upstream)
7.2
Link Command Framing Test
Test Summary
This test verifies that the PUT can tolerate link commands having one symbol error in the
LCSTART framing. The Port Configuration transaction will be used for this purpose. Here are
the combinations to be tested:
ERR
SLC SLC EPF
(incorrect symbol is D0.0)
SLC
ERR
SLC EPF
(incorrect symbol is D0.1)
SLC SLC
ERR
EPF
(incorrect symbol is D0.2)
SLC SLC SLC
ERR
(incorrect symbol is D0.3)
Test Steps and Expected Results
1.
Examiner executes the steps described in TD7.1 (Link Bring-Up Test), to bring the link to
U0, but transmits all LCRD_X link commands with an error in the first LCSTART symbol.
The test passes if the exchanges are met, no timeout is detected, all packets
are successfully received, all credits are restored and the link stays in U0 for
at least 50ms.
2.
Repeat the steps above with an error in the second, third, and fourth LCSTART symbols.
Specification Reference
Section 7.3.4#1, 2
7.3
Link Command CRC Test
Test Summary
This test verifies that the PUT initiates a recovery upon receipt of one corrupt CRC5 in each of
the two link command word (one at a time) and then both CRCs corrupted. The Port
Configuration transaction will be used for this purpose.
Reference Errata (June 2010) regarding changes to a port’s handling of an
invalid link command (Core Specification Section 7.3.2).
