1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /*
3  * Copyright (C) 2012 Regents of the University of California
4  *
5  * Derived from arch/x86/include/asm/word-at-a-time.h
6  */
7 
8 #ifndef _ASM_RISCV_WORD_AT_A_TIME_H
9 #define _ASM_RISCV_WORD_AT_A_TIME_H
10 
11 
12 #include <linux/kernel.h>
13 
14 struct word_at_a_time {
15 	const unsigned long one_bits, high_bits;
16 };
17 
18 #define WORD_AT_A_TIME_CONSTANTS { REPEAT_BYTE(0x01), REPEAT_BYTE(0x80) }
19 
20 static inline unsigned long has_zero(unsigned long val,
21 	unsigned long *bits, const struct word_at_a_time *c)
22 {
23 	unsigned long mask = ((val - c->one_bits) & ~val) & c->high_bits;
24 	*bits = mask;
25 	return mask;
26 }
27 
28 static inline unsigned long prep_zero_mask(unsigned long val,
29 	unsigned long bits, const struct word_at_a_time *c)
30 {
31 	return bits;
32 }
33 
34 static inline unsigned long create_zero_mask(unsigned long bits)
35 {
36 	bits = (bits - 1) & ~bits;
37 	return bits >> 7;
38 }
39 
40 static inline unsigned long find_zero(unsigned long mask)
41 {
42 	return fls64(mask) >> 3;
43 }
44 
45 /* The mask we created is directly usable as a bytemask */
46 #define zero_bytemask(mask) (mask)
47 
48 #endif /* _ASM_RISCV_WORD_AT_A_TIME_H */
49