Re: Strange arch/mips/delay.c

From: Ralf Baechle
Date: Sat Aug 01 2009 - 19:32:50 EST


On Sat, Aug 01, 2009 at 07:37:18PM +0200, Loïc Grenié wrote:

> I could not compile for mips without something similar to the
> following patch. As far as I can say __udelay and __ndelay
> are costly nops (with __ndelay not compiling at all) without
> the patch.
>
> At that point, it might be interesting to change
> the 0x00000005uLL by 0x00000045uLL and the >> 32
> by >> 36 (the precision is much better and the cost
> should be the same -- obviously there is a slightly higher
> risk of overlow).

Later versions of the kernel already contain a similar fix. I've not
propagated MIPS fixes into upstream -stable but the fixes are available
in the -stable branches of the MIPS git repository at
git://git.linux-mips.org/pub/scm/linux.git, the tarballs created from
that repository available for download on {ftp,www}.linux-mips.org or
on git.kernel.org.

Ralf
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/