This patch re-organises the way the zImage wrapper code is entered, to
allow more flexibility on platforms with unusual entry conditions.
After this patch, a platform .o file has two options:
1) It can define a _zimage_start, in which case the platform code gets
control from the very beginning of execution. In this case the
platform code is responsible for relocating the zImage if necessary,
clearing the BSS, performing any platform specific initialization, and
finally calling start() to load and enter the kernel.
2) It can define platform_init(). In this case the generic crt0.S
handles initial entry, and calls platform_init() before calling
start(). The signature of platform_init() is changed, however, to
take up to 5 parameters (in r3..r7) as they come from the platform's
initial loader, instead of a fixed set of parameters based on OF's
usage.
When using the generic crt0.S, the platform .o can optionally
supply a custom stack to use, using the BSS_STACK() macro. If this
is not supplied, the crt0.S will assume that the loader has
supplied a usable stack.
In either case, the platform code communicates information to the
generic code (specifically, a PROM pointer for OF systems, and/or an
initrd image address supplied by the bootloader) via a global
structure "loader_info".
In addition the wrapper script is rearranged to ensure that the
platform .o is always linked first. This means that platforms where
the zImage entry point is at a fixed address or offset, rather than
being encoded in the binary header can be supported using option (1).
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The "wrapper" script was using the wrong names for the initrd and
dtb (device-tree blob) sections. This fixes it, and also ensures
the symbols for the start and end of the dtb get defined correctly.
Signed-off-by: Paul Mackerras <paulus@samba.org>
More reorganization of the bootwrapper:
- Add dtb section to zImage
- ft_init now called by platform_init
- Pack a flat dt before calling kernel
- Remove size parameter from free
- printf only calls console_ops.write it its not NULL
- Some cleanup
Signed-off-by: Mark A. Greer <mgreer@mvista.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This puts the knowledge of how to create various sorts of zImage
wrappers into a script called "wrapper" that could be used outside of
the kernel tree. This changes arch/powerpc/boot so it first builds
the files that the wrapper script needs, then runs it to create
whatever flavours of zImage are required.
This version does uImages as well. The zImage names are changed
slightly; zImage.pseries is the one with the PT_NOTE program header
entry added, and zImage.pmac is the one without. If the
zImage.pseries gets made, it will also get hardlinked to zImage;
otherwise, if zImage.pmac is made, it gets hardlinked to zImage.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This also extends the code to handle 32-bit ELF vmlinux files as well
as 64-bit ones. This is sufficient for booting on new-world 32-bit
powermacs (i.e. all recent machines).
Signed-off-by: Paul Mackerras <paulus@samba.org>
To prove that the relocation works, move the crt0.o away from the beginning.
Move linker options from command line into linker script. rename entry point
because '_start' is referenced in printf output.
Signed-off-by: Olaf Hering <olh@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Make the zImage relocateable. So yaboot could just load and run any ELF
binary, without worrying about its load address.
Signed-off-by: Olaf Hering <olh@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove userland related stuff from ld.script, they are not required for zImage
use wildcards for some sections.
Signed-off-by: Olaf Hering <olh@suse.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Anton Blanchard <anton@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
David Gibson