ERR005198
Chip Errata for the i.MX 6Dual/6Quad and i.MX 6DualPlus/6QuadPlus, Rev. 6.1, 06/2016
NXP Semiconductors
61
The implications of this data corruption depend on the error information and the PL310
configuration. All cases listed below need to be carefully assessed to know the exact impact of the
erratum on a particular system.
DATAERR
In a system where DATAERR is tied low, this erratum does not apply as far as DATAERR is
concerned.
In a system not implementing banking on the Data RAM and not driving DATAERR constantly
low, the eviction buffer can sample transient and unstable high values of DATAERR, even if there
is actually no expected error reported to PL310. This case is the most serious consequence of this
erratum because it leads to a silent data corruption without any actual data error.
In a system using DATAERR for indicating Data RAM error and implementing banking on the
Data RAM, the eviction buffer can only sample a true error coming from the Data RAM. However,
this error may actually target another PL310 sub-block or another eviction slot. The erratum can
thus still lead to data corruption, but the latter must be put in perspective relative to the true data
error the overall system is facing. This is up to the system to assess how serious the data corruption
is compared to the RAM error.
TAGERR
In a system where TAGERR is tied low, this erratum does not apply as far as TAGERR is
concerned.
In a system using TAGERR for indicating Tag RAM error, the eviction buffer can only sample a
true error coming from the Tag RAM. However, this error may actually target another PL310
sub-block or another eviction slot. The erratum can thus still lead to data corruption, but the latter
must be put in perspective relative to the true tag error the overall system is facing. This is up to
the system to assess how serious the data corruption is compared to the RAM error.
Tag parity error
In a system not implementing parity configuration in PL310, this erratum does not apply as far as
the tag parity error is concerned.
In a system implementing parity, the eviction buffer can only sample a true tag parity error detected
by the PL310 parity logic. However, this error may actually target another PL310 sub-block or
another eviction slot. The erratum can thus still lead to a data corruption, but the latter must be put
in perspective relative to the true parity error the overall system is facing. This is up to the system
to assess how serious the data corruption is compared to the error.
Workarounds:
The following two software workarounds are available for systems affected by this erratum:
• Use write-through memory attributes for all cacheable accesses targeting PL310.
• Disable the logic responsible for generating RAM errors. This can imply disabling parity in
PL310 and/or disabling DATAERR and TAGERR generation in the RAM array, depending on
the implementation.
Proposed Solution:
No fix scheduled
