Symptom
When BIST fails, we will receive a syslog message such as "fia_driver[169]: %FABRIC-FIA_DRVR-3-ASIC_INIT_FAILURE : [4028] : Asic Initialization failed due to:mbist test failed, device 0 with error 0xfffefff5(Unknown error)", and the board will initiate a graceful reload.
After the reload, once the board comes up, we will see the syslog: "fia_driver[270]: %FABRIC-FIA_DRVR-4-MBIST_DISABLED_DUE_TO_FAILURE: MBIST Test has been disabled as it failed; RMA is recommended."
Workaround
Whenever BIST fails, Asic init will be failed and the board will initiate a graceful reload. After the reload, once the board comes up, we will see the syslog: "fia_driver[270]: %FABRIC-FIA_DRVR-4-MBIST_DISABLED_DUE_TO_FAILURE: MBIST Test has been disabled as it failed; RMA is recommended? but BIST is dynamically disabled. Therefore, no workaround or SMU is needed for the box. CSCwa55253 SMU installation is recommended to ensure that the node avoids the issue/syslog.
For version 7.3.2, the CSCwa55253 SMU is needed if the Bist fails (ASIC Initialization failed due to: MBIST test failed).
workaround:-
To disable bist:
(i) first find npu family using
show controllers fia diagshell 0 "show unit" location
(ii) edit /pkg/bin/dnx_common.bcm
add line bist_enable.=0 based on below
bist_enable.BCM88675=0 for BCM88675_B0 (J)
bist_enable.BCM88680=0 for BCM88681_A1 (J+)
bist_enable.BCM8869X=0 for BCM88690_B1(J2)
Ex: if BCM88681_A1 was the output obtained in step 1
"bist_enable.BCM88680=0" need to be added
