This allows, for example, UEFI pass a memory map with some ram in this
region, but for us to ignore it. This is the case when running under the
qemu virt machine type.
Sponsored by: ABT Systems Ltd
communicate the kernel's physical load address from where it's known in
initarm() into cpu_mp_start() which is called from non-arm code and
takes no parameters.
This adds the global variable and ensures that all the various copies
of initarm() set it. It uses the variable in cpu_mp_start(), eliminating
the last uses of KERNPHYSADDR outside of locore.S (where we can now
calculate it instead of relying on the constant).
a new physmem.c file. The new code provides helper routines that can be
used by legacy SoCs and newer FDT-based systems. There are routines to
add one or more regions of physically contiguous ram, and exclude one or
more physically contiguous regions of ram. Ram can be excluded from crash
dumps, from being given over to the vm system for allocation management,
or both. After all the included and excluded regions have been added,
arm_physmem_init_kernel_globals() processes the regions into the global
dump_avail and phys_avail arrays and realmem and physmem variables that
communicate memory configuration to the rest of the kernel.
Convert all existing SoCs to use the new helper code.