MPC85XX and QorIQ are very similar. When the DPAA dTSEC driver was
added, QORIQ_DPAA was brought in as a config option to support the differences
in hardware register settings between QorIQ (e500mc-, e5500- based) SoCs and
QUICC (e500v1/e500v2-based) SoCs, particularly in the Local Access Window (LAW)
target settings.
Unify these settings using macros to hide details and ease porting, and use a
new function (mpc85xx_is_qoriq()) to distinguish between QorIQ and QUICC SoCs at
runtime.
An alternative to using the function could be to use a variable initialized at
platform attach time, which may incur less overhead at runtime. Since it's not
in the critical path once booted, this optimization doesn't seem necessary at
first pass.