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| author | Reza Arbab <arbab@linux.ibm.com> | 2019-11-14 10:13:04 -0600 |
|---|---|---|
| committer | Vasant Hegde <hegdevasant@linux.vnet.ibm.com> | 2019-12-10 11:28:57 +0530 |
| commit | 0ecfbdd01ac0f55ac304ca946f91f7f5297b30ff (patch) | |
| tree | 4d216006274118fbbe80c83a66f643b20ab43d81 | |
| parent | a2dabb70693b0db556f112b0664bb6f4a28a79aa (diff) | |
| download | skiboot-0ecfbdd01ac0f55ac304ca946f91f7f5297b30ff.zip skiboot-0ecfbdd01ac0f55ac304ca946f91f7f5297b30ff.tar.gz skiboot-0ecfbdd01ac0f55ac304ca946f91f7f5297b30ff.tar.bz2 | |
npu2/hw-procedures: Remove assertion from check_credits()
[ Upstream commit 24664b48642845d620e225111bf6184f3c102f60 ]
The RX clock mux in the NVLink PHY can glitch, which will manifest in
hard to diagnose behavior--at best, a checkstop during the first link
traffic. The only reliable way we found to detect this was by checking
for a discrepancy in the credits we expect to receive during link
training.
Since the time the check was added, we've found that
* Commit ac6f1599ff33 ("npu2: hw-procedures: Add phy_rx_clock_sel()")
does work around the original glitch.
* Asserting is too harsh. Before root cause was established, it was
thought this could have been a manufacturing defect and we wanted to
loudly fail hardware acceptance boot cycle tests.
* It seems there is a valid situation in which credits are off from
the expected value. During GPU hot reset, a CPU prefetch across the link
can affect the credit count before we check.
Given all of the above, remove the assert().
Cc: stable # 6.0.x
Signed-off-by: Reza Arbab <arbab@linux.ibm.com>
Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Vasant Hegde <hegdevasant@linux.vnet.ibm.com>
| -rw-r--r-- | hw/npu2-hw-procedures.c | 15 |
1 files changed, 6 insertions, 9 deletions
diff --git a/hw/npu2-hw-procedures.c b/hw/npu2-hw-procedures.c index 8686462..2a03bed 100644 --- a/hw/npu2-hw-procedures.c +++ b/hw/npu2-hw-procedures.c @@ -756,17 +756,14 @@ static uint32_t check_credit(struct npu2_dev *ndev, uint64_t reg, static uint32_t check_credits(struct npu2_dev *ndev) { - int fail = 0; uint64_t val; - fail += CHECK_CREDIT(ndev, NPU2_NTL_CRED_HDR_CREDIT_RX, 0x0BE0BE0000000000ULL); - fail += CHECK_CREDIT(ndev, NPU2_NTL_RSP_HDR_CREDIT_RX, 0x0BE0BE0000000000ULL); - fail += CHECK_CREDIT(ndev, NPU2_NTL_CRED_DATA_CREDIT_RX, 0x1001000000000000ULL); - fail += CHECK_CREDIT(ndev, NPU2_NTL_RSP_DATA_CREDIT_RX, 0x1001000000000000ULL); - fail += CHECK_CREDIT(ndev, NPU2_NTL_DBD_HDR_CREDIT_RX, 0x0640640000000000ULL); - fail += CHECK_CREDIT(ndev, NPU2_NTL_ATSD_HDR_CREDIT_RX, 0x0200200000000000ULL); - - assert(!fail); + CHECK_CREDIT(ndev, NPU2_NTL_CRED_HDR_CREDIT_RX, 0x0BE0BE0000000000ULL); + CHECK_CREDIT(ndev, NPU2_NTL_RSP_HDR_CREDIT_RX, 0x0BE0BE0000000000ULL); + CHECK_CREDIT(ndev, NPU2_NTL_CRED_DATA_CREDIT_RX, 0x1001000000000000ULL); + CHECK_CREDIT(ndev, NPU2_NTL_RSP_DATA_CREDIT_RX, 0x1001000000000000ULL); + CHECK_CREDIT(ndev, NPU2_NTL_DBD_HDR_CREDIT_RX, 0x0640640000000000ULL); + CHECK_CREDIT(ndev, NPU2_NTL_ATSD_HDR_CREDIT_RX, 0x0200200000000000ULL); val = npu2_read(ndev->npu, NPU2_NTL_MISC_CFG1(ndev)); val &= 0xFF3FFFFFFFFFFFFF; |