1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _ASM_WORD_AT_A_TIME_H
3#define _ASM_WORD_AT_A_TIME_H
4
5#include <asm/compiler.h>
6
7/*
8 * word-at-a-time interface for Alpha.
9 */
10
11/*
12 * We do not use the word_at_a_time struct on Alpha, but it needs to be
13 * implemented to humour the generic code.
14 */
15struct word_at_a_time {
16	const unsigned long unused;
17};
18
19#define WORD_AT_A_TIME_CONSTANTS { 0 }
20
21/* Return nonzero if val has a zero */
22static inline unsigned long has_zero(unsigned long val, unsigned long *bits, const struct word_at_a_time *c)
23{
24	unsigned long zero_locations = __kernel_cmpbge(0, val);
25	*bits = zero_locations;
26	return zero_locations;
27}
28
29static inline unsigned long prep_zero_mask(unsigned long val, unsigned long bits, const struct word_at_a_time *c)
30{
31	return bits;
32}
33
34#define create_zero_mask(bits) (bits)
35
36static inline unsigned long find_zero(unsigned long bits)
37{
38#if defined(CONFIG_ALPHA_EV6) && defined(CONFIG_ALPHA_EV67)
39	/* Simple if have CIX instructions */
40	return __kernel_cttz(bits);
41#else
42	unsigned long t1, t2, t3;
43	/* Retain lowest set bit only */
44	bits &= -bits;
45	/* Binary search for lowest set bit */
46	t1 = bits & 0xf0;
47	t2 = bits & 0xcc;
48	t3 = bits & 0xaa;
49	if (t1) t1 = 4;
50	if (t2) t2 = 2;
51	if (t3) t3 = 1;
52	return t1 + t2 + t3;
53#endif
54}
55
56#define zero_bytemask(mask) ((2ul << (find_zero(mask) * 8)) - 1)
57
58#endif /* _ASM_WORD_AT_A_TIME_H */
59