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Message-ID: <5d546c21-169c-cacc-6ca3-becf54876f7f@linux-m68k.org>
Date:   Mon, 16 May 2022 16:08:53 +1000
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Subject: Re: [PATCH] m68knommu: fix undefined reference to `mach_get_rtc_pll'
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To:     Arnd Bergmann <arnd@arndb.de>
Cc:     Geert Uytterhoeven <geert@linux-m68k.org>,
        Linux/m68k <linux-m68k@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        kernel test robot <lkp@intel.com>
References: <20220513064952.3610672-1-gerg@linux-m68k.org>
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From:   Greg Ungerer <gerg@linux-m68k.org>
In-Reply-To: <CAK8P3a3RuOTidFpW7diHekJ6POV20SBb5PhSF943Ju1xAtOxNw@mail.gmail.com>
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Hi Arnd,

On 13/5/22 22:59, Arnd Bergmann wrote:
> On Fri, May 13, 2022 at 2:25 PM Greg Ungerer <gerg@linux-m68k.org> wrote:
>> On 13/5/22 17:12, Geert Uytterhoeven wrote:
>>> read_persistent_clock64() uses mach_hwclk(), which is provided by
>>> both setup_mm.c and setup_no.c, so it's always available?> Albeit not populated by coldfire or nommu platform code, so I see
>>> the point in depending on MMU (no nommu Amiga support yet ;-).
>>
>> Yes, exactly. And even worse is that on ColdFire platforms it
>> is never set, so will be the startup value of NULL. It is called
>> without checking for NULL in both of rtc_generic_get_time() and
>> rtc_generic_set_time().
> 
> I think that's ok because rtc_generic_{get,set}_time is only called
> from the rtc_generic driver, but that is not registered when mach_hwclk()
> is NULL.
> 
> With your patch to add the CONFIG_MMU check, you can actually
> remove the mach_hwclk() symbol from setup_no.c, and move the
> remaining RTC related symbols from setup_mm.c into the #ifdef.

Yes, I think that would be a good idea.
Tidies thins up a little.

Regards
Greg