On Apr 4, 2010, at 3:19 PM, Sebastian Andrzej Siewior wrote:

From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
=20
This adds support kexec on FSL-BookE where the MMU can not be simply
switched off. The code borrows the initial MMU-setup code to create =

the

identical mapping mapping. The only difference to the original boot =

code

is the size of the mapping(s) and the executeable address.
The kexec code maps the first 2 GiB of memory in 256 MiB steps. This
should work also on e500v1 boxes.
SMP support is still not available.
=20
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
arch/powerpc/Kconfig                          |    2 +-
arch/powerpc/include/asm/kexec.h              |   13 +++++++++
arch/powerpc/kernel/fsl_booke_entry_mapping.S |   37 =

+++++++++++++++++++++++++

arch/powerpc/kernel/head_fsl_booke.S          |    2 +
arch/powerpc/kernel/misc_32.S                 |   17 +++++++++++
5 files changed, 70 insertions(+), 1 deletions(-)

Can you explain this a bit more.  Mostly would like to have a brief =
description of the sequence of events as part of the commit message.

Something like:

* Running kernel calls machine_kexec()
* machine_kexec_32()
* jump to relocate code
* relocate clears out TLBs and sets up 2g mapping
...

what I have above might not be quite right.

- k=