[U-Boot] [PATCH] arm: Add option to disable code relocation

[Dirk Behme]

On 06.02.2012 21:25, Graeme Russ wrote:
> Hi Mike,
> 
> On Tue, Feb 7, 2012 at 6:27 AM, Mike Frysinger <vapier at gentoo.org> wrote:
>> On Monday 06 February 2012 09:49:27 Tom Rini wrote:
>>> On Mon, Feb 6, 2012 at 1:43 AM, Graeme Russ wrote:
>>>> On 02/06/2012 06:51 PM, Wolfgang Denk wrote:
>>>>> Graeme Russ wrote:
>>>>>> I think the immediate focus should be on centralising the init sequence
>>>>>> processing into /common/init.c and then bringing the new'initcall'
>>>>>> architecture online
>>>>> Agreed.
>>>>>
>>>>>> Once these have been done, any board can just specific:
>>>>>>
>>>>>> SKIP_INIT(RELOC)
>>>>> I will probably object to his, too - for the same reasons.
>>>> Considering this is a 'free' artefact of how the init sequence functions,
>>>> and that it is board specific and totally non-invasive for anyone else
>>>> (i.e. no ugly ifdef's anywhere else in the code) I'm surprised you would
>>>> object...
>>> To pick up Wolfgang's argument, but why do we want to skip relocation?
>>>  You can debug through it, it's documented (official wiki has GDB,
>>> over in TI-land, the wiki page for CCS has the bits for doing it in
>>> that Eclipse-based env, other debuggers I'm sure have a similar "now
>>> add symbols at this offset from link" option) and the end result makes
>>> it very easy for end-users to break their world (default kernel load
>>> addrs being where U-Boot would be).
>> if you have a static platform which never changes, isn't the relocation a
>> waste of time ?  i can understand wanting relocation by default for platforms
>> where memory sizes are unknown, but it's not uncommon for people to have fixed
>> hardware when they deploy.
> 
> Also, if SPL can determine total SDRAM, copy U-Boot to the final location
> and perform the relocations, there is no need for relocation to be done by
> U-Boot. As I understand it, SPL loads U-Boot into a fixed address and then
> U-Boot copies itself to top-of-RAM. We can save one copy

Yes, exactly, saving this one copy was the the reason for me to start 
this thread.

Thanks

Dirk