If we are to have driver model before relocation we need to support some
way of calling memory allocation routines.
The standard malloc() is pretty complicated:
1. It uses some BSS memory for its state, and BSS is not available before
relocation
2. It supports algorithms for reducing memory fragmentation and improving
performace of free(). Before relocation we could happily just not support
free().
3. It includes about 4KB of code (Thumb 2) and 1KB of data. However since
this has been loaded anyway this is not really a problem.
The simplest way to support pre-relocation malloc() is to reserve an area
of memory and allocate it in increasing blocks as needed. This
implementation does this.
To enable it, you need to define the size of the malloc() pool as described
in the README. It will be located above the pre-relocation stack on
supported architectures.
Note that this implementation is only useful on machines which have some
memory available before dram_init() is called - this includes those that
do no DRAM init (like tegra) and those that do it in SPL (quite a few
boards). Enabling driver model preior to relocation for the rest of the
boards is left for a later exercise.
Signed-off-by: Simon Glass <sjg@chromium.org>
Move all the C runtime setup code from every start.S
in arch/arm into arch/arm/lib/crt0.S. This covers
the code sequence from setting up the initial stack
to calling into board_init_r().
Also, rewrite the C runtime setup and make functions
board_init_*() and relocate_code() behave according to
normal C semantics (no jumping across the C stack any
more, etc).
Some SPL targets had to be touched because they use
start.S explicitly or for some reason; the relevant
maintainers and custodians are cc:ed.
Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
Some ports set up the board info structure at the same time as the global
data structure, and largely keep them together. So generate a define for
the board info struct too.
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
CONFIG_SYS_GBL_DATA_SIZE has always been just a bad workarond for not
being able to use "sizeof(struct global_data)" in assembler files.
Recent experience has shown that manual synchronization is not
reliable enough. This patch renames CONFIG_SYS_GBL_DATA_SIZE into
GENERATED_GBL_DATA_SIZE which gets automatically generated by the
asm-offsets tool. In the result, all definitions of this value can be
deleted from the board config files. We have to make sure that all
files that reference such data include the new <asm-offsets.h> file.
No other changes have been done yet, but it is obvious that similar
changes / simplifications can be done for other, related macro
definitions as well.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
A recurrent issue is that certain C level constructs like sizeof() or
offsetof() cannot be used in assembler files, which is inconvenient
when such constructs are used in the definition of macro names etc.
To avoid duplication of such definitions (and thus another cause of
problems), we adapt the Linux way to automatically generate the
respective definitions from the respective C header files.
In Linux, this is implemented in include/linux/kbuild.h, Kbuild, and
arch/*/kernel/asm-offsets.c; we adapt the code from the Linux v2.6.36
kernel tree.
We also copy the concept of the include/generated/ directory which can
be used to hold other automatically generated files as well.
We start with an architecture-independent lib/asm-offsets.c which
generates include/generated/generic-asm-offsets.h (included by
include/asm-offsets.h, which is what will be referred to in the actual
source code). Later this may be extended by architecture-specific
arch/*/lib/asm-offsets.c files that will generate a
include/generated/asm-offsets.h.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Simon Glass
Wolfgang Denk
Albert ARIBAUD
Stefan Roese
Mike Frysinger