Re: [PATCH 1/1] Changes for 68000 code integration.

[Greg Ungerer <gerg@snapgear.com>]

Hi Luis,

On 04/28/2012 12:30 AM, Luis Alves wrote:
> On Fri, Apr 27, 2012 at 3:06 PM, Greg Ungerer<gerg@snapgear.com>  wrote:
>> On 04/27/2012 09:08 AM, Luis Alves wrote:
>>> This is the first of a pack of patches to support the original 68000 cpu.
>>> This adds:
>>> á-MC68000 cpu as a choice in the config menu.
>>> á-Alcetronics M68K board (uses this cpu).
>>>
>>> What I have changed:
>>> á-CONFIG_M68000 was being used by 68328 CPUs.
>>> á Renamed to CONFIG_M68XXX. Now the 68000 and all CPU32 CPUs use this flag
>>> for common configurations.
>>> á-Modified all 68[VZ|EZ]328 to select CONFIG_MCPU32
>>> á-Modified CONFIG_MCPU32 to select CONFIG_M68XXX.
>>> á-Modified CONFIG_M68360 to select CONFIG_M68XXX (I think it was missing
>>> some settings).
>>> á-Modified some files to use CONFIG_M68XXX instead of
>>> CONFIG_M68000/CONFIG_MCPU32
>>
>>
>> Thinking on this a little more, you probably don't want most of
>> these changes. Certainly as Brad points out CPU32 and 68000 are
>> quite different, and they need to remain as separate config options.
>>
>> I can see you will end up with a arch/m68k/platform/68000 with
>> some new code. Is any of that common with what is currently in
>> arch/m68k/platform/68328? áI would expect we want to move the
>> common 68000 code into that platform/68000 directory. Longer
>> term we may want to do away with 68328/68EZ328/68VZ328 directories
>> all together. All the code may go in a platform/68000. (Still
>> thinking this one over though, but I am planning on doing away
>> with the separate 5xxx ColdFire directories real soon now).
>>
>
> I think this is a good idea. Do you suggest putting all together in the
> same file and use #ifdef's for cpu specific options? I could do that.

That may or may not make sense, we need to think about each case.
Hopefully we can keep common code together with minimal additional
#ifdefs. And put board (or on/off chip peripherals) in there own
files.


> Also, how to deal with board specific configuration files?
> As I referred in the previous mail, the 68000 has zero on-chip peripherals
> so the initial setup and configuration is a lot 'board-dependent'.

Yep. The best case is if you have specific configuration files
separate, and built based on their appropriate defines in the Makefile.
(See examples in arch/m68k/platform/coldfire/Makefile).

To start I would just put them all in the common 68000 sub-directory.
If the need arises we can start putting machine specific sub-directories
later (which is what we have at the top arch level, arch/m68k/). For
quite a few years we had machine specific directories under
platform/coldfire. But I gave up on it eventually - there was just so
much duplicated code it didn't seem to make any sense.

Regards
Greg



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Greg Ungerer  --  Principal Engineer        EMAIL:     gerg@snapgear.com
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