[PATCH] [POWERPC] bootwrapper: Allow specifying of image physical offset

[Kumar Gala]

On Mar 7, 2008, at 7:44 PM, Geoff Levand wrote:

> On 03/07/2008 08:55 AM, Kumar Gala wrote:
>> Normally we assume kernel images will be loaded at offset 0. However
>> there are situations, like when the kernel itself is running at a  
>> non-zero
>> physical address, that we don't want to load it at 0.
>>
>> Allow the wrapper to take an offset.  We use this when building u- 
>> boot images.
>>
>> Signed-off-by: Kumar Gala <galak at kernel.crashing.org>
>> ---
>> arch/powerpc/boot/Makefile |    7 +++++++
>> arch/powerpc/boot/wrapper  |   12 ++++++++++--
>> 2 files changed, 17 insertions(+), 2 deletions(-)
>>
>> diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
>> index f43dd6e..1b4bfc6 100644
>> --- a/arch/powerpc/boot/Makefile
>> +++ b/arch/powerpc/boot/Makefile
>> @@ -35,6 +35,12 @@ endif
>>
>> BOOTCFLAGS	+= -I$(obj) -I$(srctree)/$(obj) -I$(srctree)/$(src)/libfdt
>>
>> +ifdef CONFIG_MEMORY_START
>> +MEMBASE=$(CONFIG_MEMORY_START)
>
> We have the powerpc config option CONFIG_KERNEL_START.  I'm
> wondering  how this CONFIG_MEMORY_START is different.  I just
> did a quick search, and it seems that CONFIG_MEMORY_START is
> only defined for the renesas arch's.

KERNEL_START is the virtual address of the kernel.  It makes no claims  
about what the physical address is.

MEMORY_START will be the physical address that the kernel is at.  This  
will only be supported on platforms like Book-e that can have  
exception vectors at roughly any address.

- k