[PULL REQUEST] powerpc generic command line

Wed Mar 20 04:42:35 AEDT 2019

Hi Daniel,

Le 19/03/2019 à 16:38, Daniel Walker a écrit :
> On Tue, Mar 19, 2019 at 12:18:03PM +1100, Michael Ellerman wrote:
>> Hi Daniel,
>>
>> Daniel Walker <danielwa at cisco.com> writes:
>>> Here are the generic command line changes for powerpc.
>>>
>>> These changes have been in linux-next for two cycles, with few problems reported.
>>> It's also been used at Cisco Systems, Inc. in production products for many many
>>> years with no problems.
>>>
>>> Please pull these changes.
>>
>> Sorry I didn't reply to this earlier, have been busy with merge window
>> bugs and so on.
>>
>> As I imagine you noticed, I didn't pull this. There are a few reasons.
>>
>> Firstly you sent it a bit late, about a day before the 5.0 release, and
>> at 6am Saturday my time :) In future if you want me to merge something
>> please send a pull at least the ~Wednesday before the release.
>    
> Ok .. It was Friday morning my time.
> 
>> Secondly I had no idea this code was even in linux-next. I'm not sure if
>> I was Cc'ed at some point when you added it, if so sorry I missed it,
>> but I get lots of email. If you're going to add changes to arch/powerpc
>> in your next tree I'd appreciate some notice, or preferably an explicit
>> ack.
>   
> Can I have an ack now ? Since your looking at it. Do you think this has no use,
> certainly Cisco has use for it. It's still in linux-next as of now.
> 
>> The main reason I didn't merge it is that it's adding a bunch of code
>> outside of arch/powerpc, into files which I'm not the maintainer for,
>> and the patches doing so have no acks or reviews from anyone.
> 
> With the exception of the Kconfig the header file is brand new, so I'm not sure
> who would ack that. From a maintainer perspective I think you could add new
> files without issues from other maintainers.
> 
>> It's also adding a generic implementation with no indication that any
>> other arches are willing/able to use the generic implementation, which
>> begs the question whether it will actually used.
>   
> It would have been used by powerpc ;) I've gotten feedback in the past from
> Ralf Baechle who thought this was useful, however that was years ago when
> this was first submitted and the code around this area in mips has changed and
> it would require a fair amount of new work to function properly on mips.
> 
> Also , no other platforms need to use this. Powerpc could be the only user of
> it. This isn't really a question of a new exciting implementation of
> something. This is really simple, it's just consolidation across architectures.
> The implementation is vanilla, non-exciting stuff.
> 
>> I appreciate it's hard to get these sort of cross architecture changes
>> into mainline, but I don't think this is the way to do it.
>>
>> I'd suggest you post a patch series to linux-arch with the generic
>> changes and as many architecture conversions as you can manage, then get
>> some review/acks for the generic changes and chase arch maintainers for
>> some acks.
>   
> I didn't post to linux-arch , but the code has been around for years, submitted
> multiple times with more architectures than powerpc. It was scaled down to just
> powerpc to simplify it's submission.
> 
> It's really a simple set of changes, I don't think it needs as much thought as
> other cross architecture changes.
> 
>> I realise you have posted the series before, it may require some
>> persistence. There were also quite a few comments from Christophe, so
>> replying to those would be a good place to start.
>   
> I've looked at his comments, but I think he was more worried about conflicts with
> his debugging enablement, not something to stop a pull request.

Well, that's what I started with, but at the end my main worry has been 
that you bring a non exciting set of complicated macros and code to 
replace simple code, and you break something out of generic OF code to a 
new brand new generic one, instead of updating the existing generic OF code.

I like the idea behind your series very much, but I don't like too much 
the way it is proposed to be implemented. If you give me one week or 
two, I will come with a lighter proposal that should achieve the same goal.

Christophe

> 
>>> The following changes since commit ccda4af0f4b92f7b4c308d3acc262f4a7e3affad:
>>>
>>>    Linux 4.20-rc2 (2018-11-11 17:12:31 -0600)
>>>
>>> are available in the git repository at:
>>>
>>>    https://github.com/daniel-walker/cisco-linux.git for-powerpc
>>>
>>> for you to fetch changes up to 5d4514a9c291ecf19b0626695161673d35e5d549:
>>>
>>>    powerpc: convert config files to generic cmdline (2018-11-16 07:32:26 -0800)
>>>
>>> ----------------------------------------------------------------
>>> Daniel Walker (3):
>>>        add generic builtin command line
>>>        powerpc: convert to generic builtin command line
>>>        powerpc: convert config files to generic cmdline
>>>
>>>   arch/powerpc/Kconfig                          | 23 +--------
>>>   arch/powerpc/configs/44x/fsp2_defconfig       | 29 ++++++-----
>>>   arch/powerpc/configs/44x/iss476-smp_defconfig | 24 ++++-----
>>>   arch/powerpc/configs/44x/warp_defconfig       | 12 ++---
>>>   arch/powerpc/configs/holly_defconfig          | 12 ++---
>>>   arch/powerpc/configs/mvme5100_defconfig       | 25 +++++-----
>>>   arch/powerpc/configs/skiroot_defconfig        | 48 +++++++++---------
>>>   arch/powerpc/configs/storcenter_defconfig     | 15 +++---
>>
>> Also if you're updating defconfigs please don't include any unrelated
>> changes. Trimming the defconfigs can silently drop symbols and break
>> people's setups so needs to be done carefully.
>   
>> It's safer to just sed the defconfig files directly, rather than running
>> savedefconfig on them.
>   
> Ok.
> 
> Daniel
> 