On Tue, Aug 5, 2025 at 2:26 AM <sw617.shin@xxxxxxxxxxx> wrote:
>
> On Tuesday, August 5, 2025 at 2:03 PM Sam Protsenko <semen.protsenko@xxxxxxxxxx> wrote:
>
> >
> > > > + u64 t_max = n_max / freq;
> > > >
> > >
> > > Make sure this compiles on 32-bit builds.
> > >
> >
> > Can you please elaborate what might be the possible problem -- just
> > curious? I admit I never though about 32-bit case when writing that code,
> > but don't see any immediate issues with that too.
> >
>
> In my opinion, it seems that Gunter Reck's explanation is correct.
> I've found out that the error of "undefined reference to '__aeabi_uldivmod'" may occur when compiling new code on a 32-bit architecture.
Indeed. I was able to reproduce that behavior when building for ARM32 too.
> If you don't mind, I would like to proceed with maintaining the previous revision below.
> From my perspective, this approach appears to be the most reasonable solution for supporting both 32-bit and 64-bit architectures.
>
> @@ -411,8 +411,8 @@ static inline unsigned int s3c2410wdt_max_timeout(struct s3c2410_wdt *wdt)
> {
> const unsigned long freq = s3c2410wdt_get_freq(wdt);
>
> - return S3C2410_WTCNT_MAXCNT / (freq / (S3C2410_WTCON_PRESCALE_MAX + 1)
> - / S3C2410_WTCON_MAXDIV);
> + return S3C2410_WTCNT_MAXCNT / DIV_ROUND_UP(freq,
> + (S3C2410_WTCON_PRESCALE_MAX + 1) * S3C2410_WTCON_MAXDIV);
> }
>
I don't mind, although it's quite easy to fix the code I suggested by
replacing this line:
u64 t_max = n_max / freq;
with this one:
u64 t_max = div64_ul(n_max, freq);
from <math64.h>, as Guenter suggested. But I'm totally fine with your
implementation as well.
