Re: [PATCH 2/2 v3] mmc: dw_mmc: Fix the CTO overflow calculation for 32-bit systems

[Andy Shevchenko]

On Tue, Feb 27, 2018 at 5:52 AM, Jisheng Zhang
<Jisheng.Zhang@xxxxxxxxxxxxx> wrote:
> On Mon, 26 Feb 2018 20:27:22 +0000 Alexey Brodkin wrote:
>> On Mon, 2018-02-26 at 20:30 +0200, Andy Shevchenko wrote:
>> > On Mon, Feb 26, 2018 at 7:14 PM, Evgeniy Didin
>> > <Evgeniy.Didin@xxxxxxxxxxxx> wrote:
>> > > On Mon, 2018-02-26 at 18:53 +0200, Andy Shevchenko wrote:
>> > > > On Mon, Feb 26, 2018 at 5:14 PM, Evgeniy Didin

>> > > > > > IIRC, someone commented on this or similar, i.e.
>> > > > > > DIV_ROUND_UP_ULL() ?

^^^^^^^^^^^^

>> So maybe we need to add export of __udivdi3() for other arches, what do you think?

> Per my understanding, Linux kernel prefer to make use of do_div or implementations
> in <linux/math64.h> for 64bit divide

To everyone in this thread. See just above. That's solution which will work.
Other than that, drop COMPILE_TEST from the Kconfig and put a comment
that driver will not compile on architectures w/o division library.

-- 
With Best Regards,
Andy Shevchenko