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| author | 2021-01-15 08:49:57 +0200 | |
|---|---|---|
| committer | 2021-01-15 08:49:57 +0200 | |
| commit | d263dfa7d2697a43f3299b9731cd568ee49cdd2c (patch) | |
| tree | f5d993c7000ac41ee926acf0b357ec572ef7908f /arch/powerpc/include/asm/bitops.h | |
| parent | drm/i915/gt: Prune inlines (diff) | |
| parent | Merge tag 'drm-intel-gt-next-2021-01-14' of git://anongit.freedesktop.org/drm/drm-intel into drm-next (diff) | |
| download | wireguard-linux-d263dfa7d2697a43f3299b9731cd568ee49cdd2c.tar.xz wireguard-linux-d263dfa7d2697a43f3299b9731cd568ee49cdd2c.zip | |
Merge drm/drm-next into drm-intel-gt-next
Backmerging to get a common base for merging topic branches between
drm-intel-next and drm-intel-gt-next.
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Diffstat (limited to 'arch/powerpc/include/asm/bitops.h')
| -rw-r--r-- | arch/powerpc/include/asm/bitops.h | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/bitops.h b/arch/powerpc/include/asm/bitops.h index 4a4d3afd5340..299ab33505a6 100644 --- a/arch/powerpc/include/asm/bitops.h +++ b/arch/powerpc/include/asm/bitops.h @@ -216,15 +216,34 @@ static inline void arch___clear_bit_unlock(int nr, volatile unsigned long *addr) */ static inline int fls(unsigned int x) { - return 32 - __builtin_clz(x); + int lz; + + if (__builtin_constant_p(x)) + return x ? 32 - __builtin_clz(x) : 0; + asm("cntlzw %0,%1" : "=r" (lz) : "r" (x)); + return 32 - lz; } #include <asm-generic/bitops/builtin-__fls.h> +/* + * 64-bit can do this using one cntlzd (count leading zeroes doubleword) + * instruction; for 32-bit we use the generic version, which does two + * 32-bit fls calls. + */ +#ifdef CONFIG_PPC64 static inline int fls64(__u64 x) { - return 64 - __builtin_clzll(x); + int lz; + + if (__builtin_constant_p(x)) + return x ? 64 - __builtin_clzll(x) : 0; + asm("cntlzd %0,%1" : "=r" (lz) : "r" (x)); + return 64 - lz; } +#else +#include <asm-generic/bitops/fls64.h> +#endif #ifdef CONFIG_PPC64 unsigned int __arch_hweight8(unsigned int w); |
