]>
git.proxmox.com Git - mirror_ubuntu-eoan-kernel.git/blob - arch/powerpc/include/asm/bitops.h
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
3 * PowerPC atomic bit operations.
5 * Merged version by David Gibson <david@gibson.dropbear.id.au>.
6 * Based on ppc64 versions by: Dave Engebretsen, Todd Inglett, Don
7 * Reed, Pat McCarthy, Peter Bergner, Anton Blanchard. They
8 * originally took it from the ppc32 code.
10 * Within a word, bits are numbered LSB first. Lot's of places make
11 * this assumption by directly testing bits with (val & (1<<nr)).
12 * This can cause confusion for large (> 1 word) bitmaps on a
13 * big-endian system because, unlike little endian, the number of each
14 * bit depends on the word size.
16 * The bitop functions are defined to work on unsigned longs, so for a
17 * ppc64 system the bits end up numbered:
18 * |63..............0|127............64|191...........128|255...........192|
20 * |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
22 * There are a few little-endian macros used mostly for filesystem
23 * bitmaps, these work on similar bit arrays layouts, but
25 * |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
27 * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
28 * number field needs to be reversed compared to the big-endian bit
29 * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
32 #ifndef _ASM_POWERPC_BITOPS_H
33 #define _ASM_POWERPC_BITOPS_H
37 #ifndef _LINUX_BITOPS_H
38 #error only <linux/bitops.h> can be included directly
41 #include <linux/compiler.h>
42 #include <asm/asm-compat.h>
43 #include <asm/synch.h>
44 #include <asm/asm-405.h>
46 /* PPC bit number conversion */
47 #define PPC_BITLSHIFT(be) (BITS_PER_LONG - 1 - (be))
48 #define PPC_BIT(bit) (1UL << PPC_BITLSHIFT(bit))
49 #define PPC_BITMASK(bs, be) ((PPC_BIT(bs) - PPC_BIT(be)) | PPC_BIT(bs))
51 /* Put a PPC bit into a "normal" bit position */
52 #define PPC_BITEXTRACT(bits, ppc_bit, dst_bit) \
53 ((((bits) >> PPC_BITLSHIFT(ppc_bit)) & 1) << (dst_bit))
55 #define PPC_BITLSHIFT32(be) (32 - 1 - (be))
56 #define PPC_BIT32(bit) (1UL << PPC_BITLSHIFT32(bit))
57 #define PPC_BITMASK32(bs, be) ((PPC_BIT32(bs) - PPC_BIT32(be))|PPC_BIT32(bs))
59 #define PPC_BITLSHIFT8(be) (8 - 1 - (be))
60 #define PPC_BIT8(bit) (1UL << PPC_BITLSHIFT8(bit))
61 #define PPC_BITMASK8(bs, be) ((PPC_BIT8(bs) - PPC_BIT8(be))|PPC_BIT8(bs))
63 #include <asm/barrier.h>
65 /* Macro for generating the ***_bits() functions */
66 #define DEFINE_BITOP(fn, op, prefix) \
67 static __inline__ void fn(unsigned long mask, \
68 volatile unsigned long *_p) \
71 unsigned long *p = (unsigned long *)_p; \
72 __asm__ __volatile__ ( \
74 "1:" PPC_LLARX(%0,0,%3,0) "\n" \
75 stringify_in_c(op) "%0,%0,%2\n" \
77 PPC_STLCX "%0,0,%3\n" \
79 : "=&r" (old), "+m" (*p) \
80 : "r" (mask), "r" (p) \
84 DEFINE_BITOP(set_bits
, or, "")
85 DEFINE_BITOP(clear_bits
, andc
, "")
86 DEFINE_BITOP(clear_bits_unlock
, andc
, PPC_RELEASE_BARRIER
)
87 DEFINE_BITOP(change_bits
, xor, "")
89 static __inline__
void set_bit(int nr
, volatile unsigned long *addr
)
91 set_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
));
94 static __inline__
void clear_bit(int nr
, volatile unsigned long *addr
)
96 clear_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
));
99 static __inline__
void clear_bit_unlock(int nr
, volatile unsigned long *addr
)
101 clear_bits_unlock(BIT_MASK(nr
), addr
+ BIT_WORD(nr
));
104 static __inline__
void change_bit(int nr
, volatile unsigned long *addr
)
106 change_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
));
109 /* Like DEFINE_BITOP(), with changes to the arguments to 'op' and the output
111 #define DEFINE_TESTOP(fn, op, prefix, postfix, eh) \
112 static __inline__ unsigned long fn( \
113 unsigned long mask, \
114 volatile unsigned long *_p) \
116 unsigned long old, t; \
117 unsigned long *p = (unsigned long *)_p; \
118 __asm__ __volatile__ ( \
120 "1:" PPC_LLARX(%0,0,%3,eh) "\n" \
121 stringify_in_c(op) "%1,%0,%2\n" \
123 PPC_STLCX "%1,0,%3\n" \
126 : "=&r" (old), "=&r" (t) \
127 : "r" (mask), "r" (p) \
129 return (old & mask); \
132 DEFINE_TESTOP(test_and_set_bits
, or, PPC_ATOMIC_ENTRY_BARRIER
,
133 PPC_ATOMIC_EXIT_BARRIER
, 0)
134 DEFINE_TESTOP(test_and_set_bits_lock
, or, "",
135 PPC_ACQUIRE_BARRIER
, 1)
136 DEFINE_TESTOP(test_and_clear_bits
, andc
, PPC_ATOMIC_ENTRY_BARRIER
,
137 PPC_ATOMIC_EXIT_BARRIER
, 0)
138 DEFINE_TESTOP(test_and_change_bits
, xor, PPC_ATOMIC_ENTRY_BARRIER
,
139 PPC_ATOMIC_EXIT_BARRIER
, 0)
141 static __inline__
int test_and_set_bit(unsigned long nr
,
142 volatile unsigned long *addr
)
144 return test_and_set_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
)) != 0;
147 static __inline__
int test_and_set_bit_lock(unsigned long nr
,
148 volatile unsigned long *addr
)
150 return test_and_set_bits_lock(BIT_MASK(nr
),
151 addr
+ BIT_WORD(nr
)) != 0;
154 static __inline__
int test_and_clear_bit(unsigned long nr
,
155 volatile unsigned long *addr
)
157 return test_and_clear_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
)) != 0;
160 static __inline__
int test_and_change_bit(unsigned long nr
,
161 volatile unsigned long *addr
)
163 return test_and_change_bits(BIT_MASK(nr
), addr
+ BIT_WORD(nr
)) != 0;
167 static __inline__
unsigned long clear_bit_unlock_return_word(int nr
,
168 volatile unsigned long *addr
)
170 unsigned long old
, t
;
171 unsigned long *p
= (unsigned long *)addr
+ BIT_WORD(nr
);
172 unsigned long mask
= BIT_MASK(nr
);
174 __asm__
__volatile__ (
176 "1:" PPC_LLARX(%0,0,%3,0) "\n"
179 PPC_STLCX
"%1,0,%3\n"
181 : "=&r" (old
), "=&r" (t
)
182 : "r" (mask
), "r" (p
)
188 /* This is a special function for mm/filemap.c */
189 #define clear_bit_unlock_is_negative_byte(nr, addr) \
190 (clear_bit_unlock_return_word(nr, addr) & BIT_MASK(PG_waiters))
192 #endif /* CONFIG_PPC64 */
194 #include <asm-generic/bitops/non-atomic.h>
196 static __inline__
void __clear_bit_unlock(int nr
, volatile unsigned long *addr
)
198 __asm__
__volatile__(PPC_RELEASE_BARRIER
"" ::: "memory");
199 __clear_bit(nr
, addr
);
203 * Return the zero-based bit position (LE, not IBM bit numbering) of
204 * the most significant 1-bit in a double word.
206 #define __ilog2(x) ilog2(x)
208 #include <asm-generic/bitops/ffz.h>
210 #include <asm-generic/bitops/builtin-__ffs.h>
212 #include <asm-generic/bitops/builtin-ffs.h>
215 * fls: find last (most-significant) bit set.
216 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
218 static __inline__
int fls(unsigned int x
)
220 return 32 - __builtin_clz(x
);
223 #include <asm-generic/bitops/builtin-__fls.h>
225 static __inline__
int fls64(__u64 x
)
227 return 64 - __builtin_clzll(x
);
231 unsigned int __arch_hweight8(unsigned int w
);
232 unsigned int __arch_hweight16(unsigned int w
);
233 unsigned int __arch_hweight32(unsigned int w
);
234 unsigned long __arch_hweight64(__u64 w
);
235 #include <asm-generic/bitops/const_hweight.h>
237 #include <asm-generic/bitops/hweight.h>
240 #include <asm-generic/bitops/find.h>
242 /* Little-endian versions */
243 #include <asm-generic/bitops/le.h>
245 /* Bitmap functions for the ext2 filesystem */
247 #include <asm-generic/bitops/ext2-atomic-setbit.h>
249 #include <asm-generic/bitops/sched.h>
251 #endif /* __KERNEL__ */
253 #endif /* _ASM_POWERPC_BITOPS_H */