2 * Copyright 1995, Russell King.
3 * Various bits and pieces copyrights include:
4 * Linus Torvalds (test_bit).
6 * Copyright (C) 2017 Andes Technology Corporation
7 * Rick Chen, Andes Technology Corporation <rick@andestech.com>
9 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
11 * Please note that the code in this file should never be included
12 * from user space. Many of these are not implemented in assembler
13 * since they would be too costly. Also, they require priviledged
14 * instructions (which are not available from user mode) to ensure
15 * that they are atomic.
18 #ifndef __ASM_RISCV_BITOPS_H
19 #define __ASM_RISCV_BITOPS_H
23 #include <asm/system.h>
24 #include <asm-generic/bitops/fls.h>
25 #include <asm-generic/bitops/__fls.h>
26 #include <asm-generic/bitops/fls64.h>
27 #include <asm-generic/bitops/__ffs.h>
29 #define smp_mb__before_clear_bit() do { } while (0)
30 #define smp_mb__after_clear_bit() do { } while (0)
33 * Function prototypes to keep gcc -Wall happy.
35 static inline void __set_bit(int nr, void *addr)
41 mask = 1 << (nr & 0x1f);
45 #define PLATFORM__SET_BIT
47 static inline void __clear_bit(int nr, void *addr)
53 mask = 1 << (nr & 0x1f);
57 static inline void __change_bit(int nr, void *addr)
60 unsigned long *ADDR = (unsigned long *)addr;
63 mask = 1 << (nr & 31);
67 static inline int __test_and_set_bit(int nr, void *addr)
70 unsigned int *a = (unsigned int *)addr;
73 mask = 1 << (nr & 0x1f);
74 retval = (mask & *a) != 0;
79 static inline int __test_and_clear_bit(int nr, void *addr)
82 unsigned int *a = (unsigned int *)addr;
85 mask = 1 << (nr & 0x1f);
86 retval = (mask & *a) != 0;
91 static inline int __test_and_change_bit(int nr, void *addr)
94 unsigned int *a = (unsigned int *)addr;
97 mask = 1 << (nr & 0x1f);
98 retval = (mask & *a) != 0;
104 * This routine doesn't need to be atomic.
106 static inline int test_bit(int nr, const void *addr)
108 return ((unsigned char *)addr)[nr >> 3] & (1U << (nr & 7));
112 * ffz = Find First Zero in word. Undefined if no zero exists,
113 * so code should check against ~0UL first..
115 static inline unsigned long ffz(unsigned long word)
121 if (word & 0x0000ffff) {
122 k -= 16; word <<= 16;
124 if (word & 0x00ff0000) {
127 if (word & 0x0f000000) {
130 if (word & 0x30000000) {
133 if (word & 0x40000000)
140 * ffs: find first bit set. This is defined the same way as
141 * the libc and compiler builtin ffs routines, therefore
142 * differs in spirit from the above ffz (man ffs).
146 * redefined in include/linux/bitops.h
147 * #define ffs(x) generic_ffs(x)
151 * hweightN: returns the hamming weight (i.e. the number
152 * of bits set) of a N-bit word
155 #define hweight32(x) generic_hweight32(x)
156 #define hweight16(x) generic_hweight16(x)
157 #define hweight8(x) generic_hweight8(x)
159 #define ext2_set_bit test_and_set_bit
160 #define ext2_clear_bit test_and_clear_bit
161 #define ext2_test_bit test_bit
162 #define ext2_find_first_zero_bit find_first_zero_bit
163 #define ext2_find_next_zero_bit find_next_zero_bit
165 /* Bitmap functions for the minix filesystem. */
166 #define minix_test_and_set_bit(nr, addr) test_and_set_bit(nr, addr)
167 #define minix_set_bit(nr, addr) set_bit(nr, addr)
168 #define minix_test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr)
169 #define minix_test_bit(nr, addr) test_bit(nr, addr)
170 #define minix_find_first_zero_bit(addr, size) find_first_zero_bit(addr, size)
172 #endif /* __KERNEL__ */
174 #endif /* __ASM_RISCV_BITOPS_H */