newlib: fix heap user mode access for MPU devices
MPU devices that enforce power-of-two alignment now
specify the size of the buffer used for the newlib heap.
This buffer will be properly aligned and a pointer
exposed in a kernel header, such that it can be added
to a user thread's memory domain configuration if
necessary.
MPU devices that don't have these restrictions allocate
the heap as normal.
In all cases, if an MPU/MMU region needs to be programmed,
the z_newlib_get_heap_bounds() API will return the necessary
information.
Given how precious MPU regions are, no automatic programming
of the MPU is done; applications will need to do this as
needed in their memory domain configurations.
On x86, the x86 MMU-specific code has been moved to arch/x86
using the new z_newlib_get_heap_bounds() API.
Fixes: #6814
Signed-off-by: Andrew Boie <andrew.p.boie@intel.com>
4 files changed
