Re: [PATCH v2 -next] powerpc: kernel/time.c - cleanup warnings

[Christophe Leroy]

Le 24/03/2021 à 07:14, Christophe Leroy a écrit :
> Le 24/03/2021 à 00:05, Alexandre Belloni a écrit :
> > On 23/03/2021 23:18:17+0100, Alexandre Belloni wrote:
> > > Hello,
> > >
> > > On 23/03/2021 05:12:57-0400, He Ying wrote:
> > > > We found these warnings in arch/powerpc/kernel/time.c as follows:
> > > > warning: symbol 'decrementer_max' was not declared. Should it be static?
> > > > warning: symbol 'rtc_lock' was not declared. Should it be static?
> > > > warning: symbol 'dtl_consumer' was not declared. Should it be static?
> > > >
> > > > Declare 'decrementer_max' and 'rtc_lock' in powerpc asm/time.h.
> > > > Rename 'rtc_lock' in drviers/rtc/rtc-vr41xx.c to 'vr41xx_rtc_lock' to
> > > > avoid the conflict with the variable in powerpc asm/time.h.
> > > > Move 'dtl_consumer' definition behind "include <asm/dtl.h>" because it
> > > > is declared there.
> > > >
> > > > Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
> > > > Signed-off-by: He Ying <heying24@xxxxxxxxxx>
> > > > ---
> > > > v2:
> > > > - Instead of including linux/mc146818rtc.h in powerpc kernel/time.c, declare
> > > >    rtc_lock in powerpc asm/time.h.
> > >
> > > V1 was actually the correct thing to do. rtc_lock is there exactly
> > > because chrp and maple are using mc146818 compatible RTCs. This is then
> > > useful because then drivers/char/nvram.c is enabled. The proper fix
> > > would be to scrap all of that and use rtc-cmos for those platforms as
> > > this drives the RTC properly and exposes the NVRAM for the mc146818.
> > >
> > > Or at least, if there are no users for the char/nvram driver on those
> > > two platforms, remove the spinlock and stop enabling CONFIG_NVRAM or
> > > more likely rename the symbol as it seems to be abused by both chrp and
> > > powermac.
> >
> > Ok so rtc_lock is not even used by the char/nvram.c driver as it is
> > completely compiled out.
> >
> > I guess it is fine having it move to the individual platform as looking
> > very quickly at the Kconfig, it is not possible to select both
> > simultaneously. Tentative patch:
>
> Looking at it once more, it looks like including linux/mc146818rtc.h is the thing to do, at least 
> for now. Several platforms are defining the rtc_lock exactly the same way as powerpc does, and 
> including mc146818rtc.h
>
> I think that to get it clean, this change should go in a dedicated patch and do a bit more and 
> explain exactly what is being do and why. I'll try to draft something for it.
>
> He Y., can you make a version v3 of your patch excluding the rtc_lock change ?

Finally, I think there is not enough changes to justify a separate patch.

So you can send a V3 based on your V1. In addition to the changes you had in V1, please remove the 
declaration of rfc_lock in arch/powerpc/platforms/chrp/chrp.h

Christophe