Re: factor out common s2ram wakeup code

[Pavel Machek <pavel@ucw.cz>]

On Tue 2008-01-22 13:51:02, H. Peter Anvin wrote:
> Pavel Machek wrote:
>>>
>>> The biggest question is if your 16-bit code needs to touch symbols in the 
>>> 32/64-bit code, or vice versa.  That complicates things a little bit, 
>>> obviously.
>>
>> The code is in arch/x86/kernel/acpi/wakeup_32.S
>> . acpi_copy_wakeup_routine needs to know offsets within 16-bit code. I'd 
>> like to somehow call code from arch/x86/boot/video*.c
>> ... current version just took (old) .S code, and cut&paste-s it.
>>
>
> Right, I know.
>
>>> If not, the easiest way is to link the 16-bit code into a separate binary 
>>> (including both assembly and C code) which can then be included in the 
>>> kernel proper as a binary blob.  If it *does* need to reference outside 
>>> symbols, then it needs to be part of the overall link, which means 
>>> mucking with the top-level link script.
>>> That's obviously more complex.
>>>
>>> Either way, the Makefile bit of this will be a lot easier if we move the 
>>> 16-bit code into a separate directory.
>>
>> I only need arch/x86/boot/video*.c ...
>>
>>> Let me know which way you think makes more sense, and I can send you a 
>>> framework patch.
>>
>> I need to access data in that 16-bit code...
>
> Would a shared structure be OK for that?  That's easier than dealing with 
> symbols.

Shared structure would be okay, plus I need pointer to beggining and
end of code so that I can copy it to lowmem.
								Pavel
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