MPC563XM Reference Manual, Rev. 1
578
Freescale Semiconductor
Preliminary—Subject to Change Without Notice
18.4
Register Descriptions
Unless noted otherwise,
writes to the programming model must match the size of the register
, e.g., an
n
-bit
register only supports
n
-bit writes, etc. Attempted writes of a different size than the register width produce
an error termination of the bus cycle and no change to the targeted register.
18.4.1
Platform ECC Registers
For platform designs including error-correcting code (ECC) implementations to improve the quality and
reliability of memories, there are a number of program-visible registers for the sole purpose of reporting
and logging of memory failures. These optional registers include:
•
ECC Configuration Register (ECR)
•
ECC Status Register (ESR)
•
Platform Flash ECC Address Register (PFEAR)
•
Platform Flash ECC Master Number Register (PFEMR)
•
Platform Flash ECC Attributes Register (PFEAT)
•
Platform Flash ECC Data Register (PFEDR)
•
Platform RAM ECC Address Register (PREAR)
•
Platform RAM ECC Syndrome Register (PRESR)
•
Platform RAM ECC Master Number Register (PREMR)
•
Platform RAM ECC Attributes Register (PREAT)
•
Platform RAM ECC Data Register (PREDR)
The details on the ECC registers are provided in the subsequent sections.
18.4.1.1
ECC Configuration Register (ECR)
The ECC Configuration Register is an 8-bit control register for specifying which types of memory errors
are reported. In all systems with ECC, the occurrence of a non-correctable error causes the current access
to be terminated with an error condition. In many cases, this error termination is reported directly by the
initiating bus master. However, there are certain situations where the occurrence of this type of
non-correctable error is
not
reported by the master. Examples include speculative instruction fetches which
are discarded due to a change-of-flow operation, and buffered operand writes. The ECC reporting logic in
the ECSM provides an optional error interrupt mechanism to signal all non-correctable memory errors. In
addition to the interrupt generation, the ECSM captures specific information (memory address, attributes
and data, bus master number, etc.) which can be useful for subsequent failure analysis.
for the ECC Configuration Register definition.