Merge the "default" and "default-by-variant" attributes. Use an
"enabled-by" expression to select the default value based on the enabled
set. This makes it possible to select default values depending on other
options. For example you could choose memory settings based on whether
RTEMS_SMP is enabled or disabled.
The change was tested by comparing the output of
./waf bspdefaults
before and after the change.
The BSPs provide memory for the separate C Program Heap initialization
via _Memory_Get(). Most BSPs provide exactly one memory area. Only two
BSPs provide more than one memory area (arm/altera-cyclone-v and
bsps/powerpc/mpc55xxevb). Only if more than one memory area is
provided, there is a need to use _Heap_Extend(). Provide two
implementations to initialize the separate C Program Heap and let the
BSP select one of the implementations based on the number of provided
memory areas. This gets rid of a dependency on _Heap_Extend(). It
also avoids dead code sections for most BSPs.
Change licence to BSD-2-Clause according to file history.
Update #3053.
The BSPs provide memory for the workspace initialization via
_Memory_Get(). Most BSPs provide exactly one memory area. Only two
BSPs provide more than one memory area (arm/altera-cyclone-v and
bsps/powerpc/mpc55xxevb). Only if more than one memory area is
provided, there is a need to use _Heap_Extend(). Provide two
implementations to initialize the workspace handler and let the BSP
select one of the implementations based on the number of provided memory
areas. This gets rid of a dependency on _Heap_Extend(). It also avoids
dead code sections for most BSPs.
AArch64 on hardware is often started at EL2 instead of EL1 from either
u-boot or a first stage bootloader. This allows RTEMS to drop from EL2
execution to EL1 to operate as normal.
