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authorJoonas Lahtinen <joonas.lahtinen@linux.intel.com>2021-01-15 08:49:57 +0200
committerJoonas Lahtinen <joonas.lahtinen@linux.intel.com>2021-01-15 08:49:57 +0200
commitd263dfa7d2697a43f3299b9731cd568ee49cdd2c (patch)
treef5d993c7000ac41ee926acf0b357ec572ef7908f /arch/powerpc/include/asm/bitops.h
parentdrm/i915/gt: Prune inlines (diff)
parentMerge tag 'drm-intel-gt-next-2021-01-14' of git://anongit.freedesktop.org/drm/drm-intel into drm-next (diff)
downloadwireguard-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.h23
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);