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@xxxxxxxxx> --- 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; } /* -- 1.7.1