Date: Thu, 20 Jul 2017 13:31:50 +0200
From: Greg KH <gregkh@linuxfoundation.org>
To: Marcus Wolf <marcus.wolf@wolf-entwicklungen.de>
Cc: devel@driverdev.osuosl.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org, robh+dt@kernel.org, kbuild-all@01.org,
        grant.likely@linaro.org
Subject: Re: [PATCH 1/1] drivers/staging/pi433: New driver
Message-ID: <20170720113150.GA25299@kroah.com>
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On Thu, Jul 20, 2017 at 01:23:05PM +0200, Marcus Wolf wrote:
> Hi Greg,
> 
> below you can see the report with the error on m68k. It was sent to me from a
> test robot of intel.
> 
> According to my research, this problem occured, because there is no hardware
> support for floating point on the m68k (or it was configured not to use it).
> Therefore gcc uses an internal function, provided by libgcc. Obviously libgcc
> wasn't linked...
> 
> I don't know how to come arround this problem by modifying my code (except
> reducing the accuracy of the calculation by not using floating point).
> 
> Can we ignore the error or can I do something else?
> Maybe a special include just in case of m68k can help??!?
> I don't have an environment for building m68k.

It looks like a 64bit issue, try wrapping your division in that function
with a call to do_div() like you do elsewhere in that function.  That
should solve the issue.

thanks,

greg k-h