This commit enables multi-processing for all Cortex A9 SoCs we currently
support. Moreover, it thereby enables the L2 cache for i.MX6 that was not
enabled until now. However, the QEMU variants hw_pbxa9 and hw_zynq still
only use 1 core, because the busy cpu synchronization used when initializing
multiple Cortex A9 cores leads to horrible boot times on QEMU.
During this work the CPU initialization in general was reworked. From now
on lots of hardware specifics were put into the 'spec' specific files, some
generic hook functions and abstractions thereby were eliminated. This
results to more lean implementations for instance on non-SMP platforms,
or in the x86 case where cache maintainance is a non-issue.
Due to the fact that memory/cache coherency and SMP are closely coupled
on ARM Cortex A9 this commit combines so different aspects.
Fix#1312Fix#1807
Instead of holding SPEC-variable dependent files and directories inline
within the repository structure, move them into 'spec' subdirectories
at the corresponding levels, e.g.:
repos/base/include/spec
repos/base/mk/spec
repos/base/lib/mk/spec
repos/base/src/core/spec
...
Moreover, this commit removes the 'platform' directories. That term was
used in an overloaded sense. All SPEC-relative 'platform' directories are
now named 'spec'. Other files, like for instance those related to the
kernel/architecture specific startup library, where moved from 'platform'
directories to explicit, more meaningful places like e.g.: 'src/lib/startup'.
Fix#1673
The port uses the Cortex-A9 private timer for the kernel and an EPIT as
user timer. It was successfully tested on the Wandboard Quad and the CuBox-i
with the signal test. It lacks L2-cache and Trustzone support by now.
Thanks to Praveen Srinivas (IIT Madras, India) and Nikolay Golikov (Ksys Labs
LLC, Russia). This work is partially based on their contributions.
Fix#1467
