This is largely a conceptual change rather than an actual change.
Instead of using an array of interrupt stacks (one for each IRQ
nesting level), we use one interrupt stack and subdivide it. The
effect is the same, but this is more in line with the Zephyr model
of one ISR stack per CPU (as reflected in init.c).
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Fleshed out z_arch_esf_t and added code to build this frame when
exceptions occur. Created a separate small stack for exceptions and
shifted the initialization code to use this instead of the IRQ stack.
Moved IRQ stack(s) to irq.c.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>
Using the arch Kconfig here, instead of kernel/Kconfig. Intel64 with
the SysV ABI requires some pretty big stacks. These 4K-8K defaults
are arguably a bit small, but the Zephyr defaults are REALLY too small.
Signed-off-by: Charles E. Youse <charles.youse@intel.com>