1 files changed, 55 insertions, 0 deletions

diff --git a/arch/alpha/include/asm/word-at-a-time.h b/arch/alpha/include/asm/word-at-a-time.h
new file mode 100644
index 000000000000..6b340d0f1521
--- /dev/null
+++ b/arch/alpha/include/asm/word-at-a-time.h
@@ -0,0 +1,55 @@
+#ifndef _ASM_WORD_AT_A_TIME_H
+#define _ASM_WORD_AT_A_TIME_H
+
+#include <asm/compiler.h>
+
+/*
+ * word-at-a-time interface for Alpha.
+ */
+
+/*
+ * We do not use the word_at_a_time struct on Alpha, but it needs to be
+ * implemented to humour the generic code.
+ */
+struct word_at_a_time {
+        const unsigned long unused;
+};
+
+#define WORD_AT_A_TIME_CONSTANTS { 0 }
+
+/* Return nonzero if val has a zero */
+static inline unsigned long has_zero(unsigned long val, unsigned long *bits, const struct word_at_a_time *c)
+{
+        unsigned long zero_locations = __kernel_cmpbge(0, val);
+        *bits = zero_locations;
+        return zero_locations;
+}
+
+static inline unsigned long prep_zero_mask(unsigned long val, unsigned long bits, const struct word_at_a_time *c)
+{
+        return bits;
+}
+
+#define create_zero_mask(bits) (bits)
+
+static inline unsigned long find_zero(unsigned long bits)
+{
+#if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
+        /* Simple if have CIX instructions */
+        return __kernel_cttz(bits);
+#else
+        unsigned long t1, t2, t3;
+        /* Retain lowest set bit only */
+        bits &= -bits;
+        /* Binary search for lowest set bit */
+        t1 = bits & 0xf0;
+        t2 = bits & 0xcc;
+        t3 = bits & 0xaa;
+        if (t1) t1 = 4;
+        if (t2) t2 = 2;
+        if (t3) t3 = 1;
+        return t1 + t2 + t3;
+#endif
+}
+
+#endif /* _ASM_WORD_AT_A_TIME_H */