Date: Thu, 20 Jul 2017 14:37:05 +0300
From: Dan Carpenter <dan.carpenter@oracle.com>
To: Marcus Wolf <marcus.wolf@wolf-entwicklungen.de>
Cc: Greg KH <gregkh@linuxfoundation.org>, 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
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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).

I don't see any floating point?  You're not allowed to use floating
point in the kernel.

> 
> 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.
> 

I think the answer is to use div_u64() and div64_u64 instead of
do_div()?  Or you could just add a depend in the Kconfig.

regards,
dan carpenter