lkml.org 
[lkml]   [2018]   [May]   [14]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] m68k: Implement ndelay() as an inline function to force type checking/casting
Hi Boris,

On Mon, May 14, 2018 at 11:29 AM, Geert Uytterhoeven
<geert@linux-m68k.org> wrote:
> On Sun, May 13, 2018 at 4:02 PM, Boris Brezillon
> <boris.brezillon@bootlin.com> wrote:
>> ndelay() is supposed to take an unsigned long, but if you define
>> ndelay() as a macro and the caller pass an unsigned long long instead
>> of an unsigned long, the unsigned long long to unsigned long cast is
>> not done and we end up with an "undefined reference to `__udivdi3'"
>> error at link time.
>>
>> Fix that by making ndelay() an inline function and then defining dummy
>> ndelay() macro that redirects to the ndelay() function (it's how most
>> archs do to implement ndelay()).
>>
>> Fixes: c8ee038bd148 ("m68k: Implement ndelay() based on the existing udelay() logic")
>> Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
>> ---
>> Hello Geert,
>>
>> This patch is fixing the bug reported by kbuild test robot here [1].
>> I could have patched the PSEC_TO_NSEC() macro to cast the result of
>> the division on a u32, but I thought making m68k consistent with what
>> other archs do would be preferable.
>>
>> Let me know if don't like the solution, and I'll patch the ndelay()
>> caller instead.
>
> Thanks for your patch!
>
> With the comment a few lines above removed:
>
> - * This is a macro so that the const version can factor out the first
> - * multiply and shift.
>
> Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>

I've just posted a fix for the root cause ("[PATCH] mtd: nand: Fix return
type of __DIVIDE() when called with 32-bit",
https://lkml.org/lkml/2018/5/14/578), so the fix for m68k's ndelay() is not
that urgent anymore.

As your patch is still a valid fix, I'll apply it, and queue it up for v4.18.

Thanks!

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds

\
 
 \ /
  Last update: 2018-05-14 12:53    [W:0.069 / U:0.148 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site