When in SMP mode, the nested/irq_stack/current fields are specific to
the current CPU and not to the kernel as a whole, so we need an array
of these. Place them in a _cpu_t struct and implement a
_arch_curr_cpu() function to retrieve the pointer.
When not in SMP mode, the first CPU's fields are defined as a unioned
with the first _cpu_t record. This permits compatibility with legacy
assembly on other platforms. Long term, all users, including
uniprocessor architectures, should be updated to use the new scheme.
Fundamentally this is just renaming: the structure layout and runtime
code do not change on any existing platforms and won't until someone
defines a second CPU.
Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
Esp-idf defines the BIT macro that is also defined in Zephyr's
misc/util.h. Fix the issue by including the esp-idf headers first, so
that a check in util.h won't redefine the macro if it's already
defined.
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>
The first stage bootloader, part of the ESP32 ROM, already sets up
a stack that's sufficient to execute C programs. So, instead of
implementing __stack() in assembly, do it in C to simplify things
slightly.
This ESP32-specific initialization will perform the following:
- Disable the watchdog timer that's enabled by the bootloader
- Move exception handlers to IRAM
- Disable normal interrupts
- Disable the second CPU
- Zero out the BSS segment
Things that might be performed in the future include setting up the
CPU frequency, memory protection regions, and enabling the flash
cache.
Signed-off-by: Leandro Pereira <leandro.pereira@intel.com>