summaryrefslogtreecommitdiff
path: root/include/asm-frv/bitops.h
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-frv/bitops.h
downloadlwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.gz
lwn-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.zip
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-frv/bitops.h')
-rw-r--r--include/asm-frv/bitops.h341
1 files changed, 341 insertions, 0 deletions
diff --git a/include/asm-frv/bitops.h b/include/asm-frv/bitops.h
new file mode 100644
index 000000000000..b664bd5b6663
--- /dev/null
+++ b/include/asm-frv/bitops.h
@@ -0,0 +1,341 @@
+/* bitops.h: bit operations for the Fujitsu FR-V CPUs
+ *
+ * For an explanation of how atomic ops work in this arch, see:
+ * Documentation/fujitsu/frv/atomic-ops.txt
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <asm/byteorder.h>
+#include <asm/system.h>
+#include <asm/atomic.h>
+
+#ifdef __KERNEL__
+
+/*
+ * ffz = Find First Zero in word. Undefined if no zero exists,
+ * so code should check against ~0UL first..
+ */
+static inline unsigned long ffz(unsigned long word)
+{
+ unsigned long result = 0;
+
+ while (word & 1) {
+ result++;
+ word >>= 1;
+ }
+ return result;
+}
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+static inline int test_and_clear_bit(int nr, volatile void *addr)
+{
+ volatile unsigned long *ptr = addr;
+ unsigned long mask = 1UL << (nr & 31);
+ ptr += nr >> 5;
+ return (atomic_test_and_ANDNOT_mask(mask, ptr) & mask) != 0;
+}
+
+static inline int test_and_set_bit(int nr, volatile void *addr)
+{
+ volatile unsigned long *ptr = addr;
+ unsigned long mask = 1UL << (nr & 31);
+ ptr += nr >> 5;
+ return (atomic_test_and_OR_mask(mask, ptr) & mask) != 0;
+}
+
+static inline int test_and_change_bit(int nr, volatile void *addr)
+{
+ volatile unsigned long *ptr = addr;
+ unsigned long mask = 1UL << (nr & 31);
+ ptr += nr >> 5;
+ return (atomic_test_and_XOR_mask(mask, ptr) & mask) != 0;
+}
+
+static inline void clear_bit(int nr, volatile void *addr)
+{
+ test_and_clear_bit(nr, addr);
+}
+
+static inline void set_bit(int nr, volatile void *addr)
+{
+ test_and_set_bit(nr, addr);
+}
+
+static inline void change_bit(int nr, volatile void * addr)
+{
+ test_and_change_bit(nr, addr);
+}
+
+static inline void __clear_bit(int nr, volatile void * addr)
+{
+ volatile unsigned long *a = addr;
+ int mask;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ *a &= ~mask;
+}
+
+static inline void __set_bit(int nr, volatile void * addr)
+{
+ volatile unsigned long *a = addr;
+ int mask;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ *a |= mask;
+}
+
+static inline void __change_bit(int nr, volatile void *addr)
+{
+ volatile unsigned long *a = addr;
+ int mask;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ *a ^= mask;
+}
+
+static inline int __test_and_clear_bit(int nr, volatile void * addr)
+{
+ volatile unsigned long *a = addr;
+ int mask, retval;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ retval = (mask & *a) != 0;
+ *a &= ~mask;
+ return retval;
+}
+
+static inline int __test_and_set_bit(int nr, volatile void * addr)
+{
+ volatile unsigned long *a = addr;
+ int mask, retval;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+ return retval;
+}
+
+static inline int __test_and_change_bit(int nr, volatile void * addr)
+{
+ volatile unsigned long *a = addr;
+ int mask, retval;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 31);
+ retval = (mask & *a) != 0;
+ *a ^= mask;
+ return retval;
+}
+
+/*
+ * This routine doesn't need to be atomic.
+ */
+static inline int __constant_test_bit(int nr, const volatile void * addr)
+{
+ return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
+}
+
+static inline int __test_bit(int nr, const volatile void * addr)
+{
+ int * a = (int *) addr;
+ int mask;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ return ((mask & *a) != 0);
+}
+
+#define test_bit(nr,addr) \
+(__builtin_constant_p(nr) ? \
+ __constant_test_bit((nr),(addr)) : \
+ __test_bit((nr),(addr)))
+
+extern int find_next_bit(const unsigned long *addr, int size, int offset);
+
+#define find_first_bit(addr, size) find_next_bit(addr, size, 0)
+
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
+
+static inline int find_next_zero_bit(const void *addr, int size, int offset)
+{
+ const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
+ unsigned long result = offset & ~31UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if (offset) {
+ tmp = *(p++);
+ tmp |= ~0UL >> (32-offset);
+ if (size < 32)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size & ~31UL) {
+ if (~(tmp = *(p++)))
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp |= ~0UL >> size;
+found_middle:
+ return result + ffz(tmp);
+}
+
+#define ffs(x) generic_ffs(x)
+#define __ffs(x) (ffs(x) - 1)
+
+/*
+ * fls: find last bit set.
+ */
+#define fls(x) \
+({ \
+ int bit; \
+ \
+ asm("scan %1,gr0,%0" : "=r"(bit) : "r"(x)); \
+ \
+ bit ? 33 - bit : bit; \
+})
+
+/*
+ * Every architecture must define this function. It's the fastest
+ * way of searching a 140-bit bitmap where the first 100 bits are
+ * unlikely to be set. It's guaranteed that at least one of the 140
+ * bits is cleared.
+ */
+static inline int sched_find_first_bit(const unsigned long *b)
+{
+ if (unlikely(b[0]))
+ return __ffs(b[0]);
+ if (unlikely(b[1]))
+ return __ffs(b[1]) + 32;
+ if (unlikely(b[2]))
+ return __ffs(b[2]) + 64;
+ if (b[3])
+ return __ffs(b[3]) + 96;
+ return __ffs(b[4]) + 128;
+}
+
+
+/*
+ * hweightN: returns the hamming weight (i.e. the number
+ * of bits set) of a N-bit word
+ */
+
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+#define ext2_set_bit(nr, addr) test_and_set_bit ((nr) ^ 0x18, (addr))
+#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, (addr))
+
+#define ext2_set_bit_atomic(lock,nr,addr) ext2_set_bit((nr), addr)
+#define ext2_clear_bit_atomic(lock,nr,addr) ext2_clear_bit((nr), addr)
+
+static inline int ext2_test_bit(int nr, const volatile void * addr)
+{
+ const volatile unsigned char *ADDR = (const unsigned char *) addr;
+ int mask;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ return ((mask & *ADDR) != 0);
+}
+
+#define ext2_find_first_zero_bit(addr, size) \
+ ext2_find_next_zero_bit((addr), (size), 0)
+
+static inline unsigned long ext2_find_next_zero_bit(const void *addr,
+ unsigned long size,
+ unsigned long offset)
+{
+ const unsigned long *p = ((const unsigned long *) addr) + (offset >> 5);
+ unsigned long result = offset & ~31UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if(offset) {
+ /* We hold the little endian value in tmp, but then the
+ * shift is illegal. So we could keep a big endian value
+ * in tmp, like this:
+ *
+ * tmp = __swab32(*(p++));
+ * tmp |= ~0UL >> (32-offset);
+ *
+ * but this would decrease preformance, so we change the
+ * shift:
+ */
+ tmp = *(p++);
+ tmp |= __swab32(~0UL >> (32-offset));
+ if(size < 32)
+ goto found_first;
+ if(~tmp)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while(size & ~31UL) {
+ if(~(tmp = *(p++)))
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if(!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ /* tmp is little endian, so we would have to swab the shift,
+ * see above. But then we have to swab tmp below for ffz, so
+ * we might as well do this here.
+ */
+ return result + ffz(__swab32(tmp) | (~0UL << size));
+found_middle:
+ return result + ffz(__swab32(tmp));
+}
+
+/* Bitmap functions for the minix filesystem. */
+#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
+#define minix_set_bit(nr,addr) ext2_set_bit(nr,addr)
+#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
+#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
+#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_BITOPS_H */