[PATCH 3/3] powerpc/kexec: Add support for FSL-BookE

[Kumar Gala]

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

> From: Sebastian Andrzej Siewior <bigeasy at linutronix.de>
> 
> 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.
> 
> Signed-off-by: Sebastian Andrzej Siewior <bigeasy at 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