From f67887e3ff68d0986702ae79961d795d9793cc8f Mon Sep 17 00:00:00 2001 From: Reza Arbab Date: Thu, 14 Nov 2019 10:13:04 -0600 Subject: 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 Signed-off-by: Oliver O'Halloran Signed-off-by: Vasant Hegde --- hw/npu2-hw-procedures.c | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-) diff --git a/hw/npu2-hw-procedures.c b/hw/npu2-hw-procedures.c index c1ae8f1..24447a4 100644 --- a/hw/npu2-hw-procedures.c +++ b/hw/npu2-hw-procedures.c @@ -783,17 +783,14 @@ 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 &= 0xFF3FFFFFFFFFFFFFUL; -- cgit v1.1