SPRZ429N July   2014  – July 2024 AM5726 , AM5728 , AM5729

 

  1.   1
  2. 1Introduction
    1.     Related Documentation
    2.     Trademarks
    3.     Modules Impacted
  3. 2Silicon Advisories
    1.     Revisions SR 2.0, 1.1 - Advisories List
    2.     i202
    3.     i378
    4.     i631
    5.     i694
    6.     i698
    7.     i699
    8.     i727
    9.     i729
    10.     i734
    11.     i767
    12.     i782
    13.     i783
    14.     i802
    15.     i803
    16.     i807
    17.     i808
    18.     i809
    19.     i810
    20.     i813
    21.     i814
    22.     i815
    23.     i818
    24.     i819
    25.     i820
    26.     i824
    27.     i826
    28.     i829
    29.     i834
    30.     i837
    31.     i840
    32.     i841
    33.     i842
    34.     i843
    35.     i847
    36.     i849
    37.     i852
    38.     i854
    39.     i855
    40.     i856
    41.     i859
    42.     i861
    43.     i862
    44.     i863
    45.     i868
    46.     i869
    47.     i870
    48.     i871
    49.     i872
    50.     i874
    51.     i875
    52.     i878
    53.     i879
    54.     i880
    55.     i882
    56.     i883
    57.     i884
    58.     i887
    59.     i889
    60.     i890
    61.     i893
    62.     i895
    63.     i896
    64.     i897
    65.     i898
    66.     i899
    67.     i900
    68.     i901
    69.     i903
    70.     i916
    71.     i927
    72.     i929
    73.     i930
    74.     i932
    75.     i933
    76.     i936
    77.     i940
    78.     i2446
  4. 3Silicon Limitations
    1.     Revisions SR 2.0, 1.1 - Limitations List
    2.     i596
    3.     i641
    4.     i833
    5.     i838
    6.     i845
    7.     i848
    8.     i850
    9.     i851
    10.     i853
    11.     i857
    12.     i858
    13.     i876
    14.     i877
    15.     i892
    16.     i909
    17.     i922
    18.     i925
  5. 4Silicon Cautions
    1.     Revisions SR 2.0, 1.1 - Cautions List
    2. 4.1 106
    3.     i827
    4.     i832
    5.     i836
    6.     i839
    7.     i864
    8.     i885
    9.     i886
    10.     i912
    11.     i926
    12.     i931
    13.     i935
  6. 5Revision History

i895

EMIF_FW: System Hang When EMIF Firewall Is Reconfigured While There Is Activity on EMIF Interface

CRITICALITY

High

DESCRIPTION

If there is ongoing activity on the EMIF interface via the DMM path, any reconfiguration of EMIF_FW firewall instance can result in a system hang. This applies only to the EMIF_FW firewall instance. All other firewall instances can be safely re-configured at run-time using the sequence mentioned in TRM.

To reconfigure the firewall configuration at run-time, following sequence is to be followed:

  1. Set the REGUPDATE_CONTROL[0] BUSY_REQ bit to 0x1 to ensure that no transaction can reach the slave NIU (suspend).
  2. Update the firewall registers as required.
  3. Set the REGUPDATE_CONTROL[0] BUSY_REQ bit to 0x0 to resume the transactions.

In case of EMIF_FW firewall instance, the transactions to the slave (EMIF) are not blocked correctly in step 1 mentioned above. Initiator remains unaware that EMIF is not accepting commands and waits indefinitely for a response resulting in a system hang.

WORKAROUND

EMIF_FW firewall instance should not be reconfigured when there is on-going activity on the EMIF interface.

Following choices can be made based on practical constraints in the system.

  1. All firewall configurations are done one-time during the initial boot-up phase where EMIF transactions can be easily guaranteed to be not active. This will typically be done by a secondary boot loader or any other initialization software.
  2. Using inter-processor communication between all the cores in the system, ensure that there is no activity on the EMIF interface. At this point, firewall can be reconfigured safely.
  3. For some use-cases, to achieve same effect as changing firewall configuration at run-time, user can use a combination of DMM/MMU/Firewalls. In this case, firewall configuration is done only once during boot. Access permissions are controlled using aliased memory map created using DMM and controlling access to this aliased memory map using MMU.

REVISIONS IMPACTED

SR 2.0, 1.1

TDA2x: 2.0, 1.1, 1.0

DRA75x, DRA74x: 2.0, 1.1, 1.0

AM572x: 2.0, 1.1