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Link Layer Tests
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The tested CRC-5 error conditions are:
Incorrect CRC-5 in first Link Command Word
Incorrect CRC-5 in second Link Command Word
Incorrect CRC in both Link Command Words
Test Steps and Expected Results
1.
Examiner executes the steps described in section TD7.1 (Link Bring-Up Test) to bring the
link to U0, but transmits all LCRD_X link commands with the first condition listed above.
The test passes if port under test initiates a recovery sequence (upon
expiration of the Credit_HP_Timer at 50%) as a result of receiving a
link command with one or two incorrect CRC5s, and returns to U0 for at least
50ms.
2.
Repeat the step above using the second and third conditions listed above.
Specification Reference
Section 7.3.4#2
7.4
Invalid Link Command Test
Test Summary
This test verifies that the PUT will ignore an invalid link command (first and second LCW
containing different commands). The tested condition is:
Link command with LGO_U1 in the first LCW and LGO_U2 in the second LCW, with good
CRC-5 calculations on both LCWs.
Test Steps and Expected Results
1.
Examiner executes steps described in TD7.1 (Link Bring-Up Test) to bring the link to U0.
2.
Examiner sends the link command described above, following the completion of link
advertisement sequences.
The test fails if the port under test replies with LXU or LAU.
The test passes if the link command is ignored, all exchanges are correct, no
timeout is detected, all packets are successfully received by the PUT, all
credits are restored and the link stays in U0 for at least 50ms.
