On Sun, Jun 27, 2010 at 08:44:03AM -0500, Shinya Kuribayashi wrote:
> fls()/__fls() defined at <asm/bitops.h>, doesn't use CLZ unless it's
> explicitly requested via <cpu-features-overrides.h>. In other words,
> as long as depending on cpu_data[0].isa_level, CLZ is nerver used for
> fls()/__fls().
>
> Looking at leftover clz() in asic_int.c, PowerTV used to use Malta's
> clz() and irq_ffs() as-is, then for some reason made a decision not to
> use clz().
>
> It's MIPS32 machine and luckily clz() is left there, then let's go back
> to the original shape.
>
> Signed-off-by: Shinya Kuribayashi <skuribay@pobox.com>
> ---
>
> Compile checked, and now CLZ is back.
>
> arch/mips/powertv/asic/asic_int.c | 2 +-
> 1 files changed, 1 insertions(+), 1 deletions(-)
>
> diff --git a/arch/mips/powertv/asic/asic_int.c
> b/arch/mips/powertv/asic/asic_int.c
> index 529c44a..e3c08a2 100644
> --- a/arch/mips/powertv/asic/asic_int.c
> +++ b/arch/mips/powertv/asic/asic_int.c
> @@ -86,7 +86,7 @@ static inline int clz(unsigned long x)
> */
> static inline unsigned int irq_ffs(unsigned int pending)
> {
> - return fls(pending) - 1 + CAUSEB_IP;
> + return -clz(pending) + 31 - CAUSEB_IP;
> }
>
> /*
Thanks, I'll try this out.
--
David VL
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