Heads up: Linus plans to kill ARM defconfigs

[Eric Miao]

On Fri, Jun 4, 2010 at 9:37 AM, Marek Vasut <marek.vasut at gmail.com> wrote:
> Dne Pá 4. června 2010 03:35:28 Eric Miao napsal(a):
>> On Fri, Jun 4, 2010 at 9:16 AM, Ryan Mallon <ryan at bluewatersys.com> wrote:
>> > Marek Vasut wrote:
>> >> Dne Pá 4. června 2010 01:33:35 Ryan Mallon napsal(a):
>> >>> Nicolas Pitre wrote:
>> >>>> On Fri, 4 Jun 2010, Ryan Mallon wrote:
>> >>>>> Is it worth being a bit proactive and getting rid of some of them in
>> >>>>> advance? Things like spear3[012]0_defconfig are basically identically
>> >>>>> except for the board type. Combining all three of those would remove
>> >>>>> 1500 lines of code.
>> >>>>
>> >>>> Please go ahead with a patch.
>> >>>
>> >>> Hmm, not as easy as I thought. The three boards cannot be built into a
>> >>> single kernel since the arch/arm/mach-spear3xx/spear3[012]0.c files all
>> >>> extern a bunch of structs which have naming conflicts.
>> >>>
>> >>> It does look possible to rewrite that code so that all three boards can
>> >>> be built into a single kernel. I can try and put together a patch, but
>> >>> I don't have any hardware to test with.
>> >>>
>> >>> The at91 is actually in a similar state, where only one of the
>> >>> at91sam9260, at91sam9g45, etc can be selected. Again, it should be
>> >>> possible to rework the code so that most of the different cpus can be
>> >>> built into a single kernel. I'm sure other mach's are in a simliar
>> >>> state. Fixing these where possible would allow us to have single
>> >>> defconfigs per mach directory and reduce code churn, which is what
>> >>> Linus is really complaining about.
>> >>
>> >> I just tested, PXA (mach-pxa) probably can be compiled into single
>> >> kernel supporting all the boards.
>> >
>> > Yes, IIRC Russell and Eric did a huge amount of work to get pxa into
>> > that state.
>> >
>> > ryan at okiwi:configs$ grep "ARCH_PXA=y" * | wc -l
>> > 25
>> >
>> > Can we remove/combine some of those?
>>
>> Definitely. In the end of the day, I would like to see pxa_defconfig only.
>> But at the moment, I need every board maintainer to review their defconfig
>> and combine them as much as possible. E.g.
>>
>> palmte_defconfig   palmtt_defconfig   palmz71_defconfig  palmz72_defconfig
>
> This is OMAP stuff, not PXA. But yeah, these could be combined. I don't have
> these devices available at the moment (and it might be a problem getting them
> into operational state).
>>
>> I'd guess can simply combine into one. (Marek, feel free to do it)
>>
>> I'd more like a step to step work instead of a brutely removal of all
>> defconfig, not sure if Linus is going to buy in.
>>
>> For those sub-arch which cannot simply compile a single kernel for multiple
>> boards, s5p* as previously mentioned, I suggest not to introduce any new
>> defconfig until the problem is solved.
>>
>> Also, we are now working on a single kernel for multiple sub-arch (at least
>> what Nicolas and I am doing now, and welcome to join us). It's tough (the
>> way to handle different phys_offset is only the tip of the iceberg) and
>> seems now more and more necessary. so hopefully by the end of the day, we
>> may possible end up with only very few defconfig.
>
> How long is your day now ?
>

In the end of the day, sorry, it's a very long. You know English is not my
tongue ;-)