Teledyne LeCroy Protocol PCI Express Script Automation Test Tool - Manual (Page 24)

Teledyne LeCroy PCI Express Script Automation Test Tool User Manual
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3.1.1.4 Test 52-12. REPLAY_NUM Test
ASSERTIONS COVERED: DLL.5.2#1.2
The intent of this test is to ensure that a DUT keeps retransmitting a transaction for which a NAK has been issued on
purpose until the number of times in its REPLAY_NUM.
Trainer Stimulus: link_52-12_REPLAY_NUM.peg
Recording Options: link_layer_common.rec
Verification Scripts: link_52-12_REPLAY_NUM.pevs
Test Algorithm:
1. Write 0x0000000F to Device Control Register, to enable Error Reporting for all error types.
2. Write 0xFFFFFFFF to Advanced Uncorrectable Error Status Register, to clear all prior error bits.
3. Write 0xFFFFFFFF to Advanced Correctable Error Status Register, to clear all prior error bits.
4. Main test stage. Do the following:
a. Set the Ack/Nak policy to “Always Nak”.
b. Send configuration read request TLP.
c. Wait for the completion TLP to arrive for REPLAY_NUM times, while sending Nak.
d. Switch back to Automatic Ack policy.
e. Acknowledge the next completion TLP.
5. Read Device Status Register. No error bits should be set.
6. Read Advanced Uncorrectable Error Status Register. No error bits should be set.
7. Read Advanced Correctable Error Status Register. No error bits should be set.
8. Write 0 to Device Control Register, to disable Error Reporting for all error types.
Pass/Fail Criteria:
Test should successfully progress though all test stages.
All test stages should be executed without protocol violations.
Verify that:
a) The DUT transmits the CONFIG_RD_COMPLETION for REPLAY_NUM of times with the same sequence
number.
b) The DUT did not set any error bit in its Device Status register and did not generate any error messages.
c) The DUT did not set any error bit in the Advanced Error Reporting registers (if implemented).
If the DUT meets all these criteria, the DUT passes the test.