Initial revision

1 files changed, 144 insertions, 0 deletions

diff --git a/include/asm-arm/bitops.h b/include/asm-arm/bitops.h
new file mode 100644
index 0000000..4733858
--- /dev/null
+++ b/include/asm-arm/bitops.h
@@ -0,0 +1,144 @@
+/*
+ * Copyright 1995, Russell King.
+ * Various bits and pieces copyrights include:
+ *  Linus Torvalds (test_bit).
+ *
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ *
+ * Please note that the code in this file should never be included
+ * from user space.  Many of these are not implemented in assembler
+ * since they would be too costly.  Also, they require priviledged
+ * instructions (which are not available from user mode) to ensure
+ * that they are atomic.
+ */
+
+#ifndef __ASM_ARM_BITOPS_H
+#define __ASM_ARM_BITOPS_H
+
+#ifdef __KERNEL__
+
+#define smp_mb__before_clear_bit()	do { } while (0)
+#define smp_mb__after_clear_bit()	do { } while (0)
+
+/*
+ * Function prototypes to keep gcc -Wall happy.
+ */
+extern void set_bit(int nr, volatile void * addr);
+
+static inline void __set_bit(int nr, volatile void *addr)
+{
+	((unsigned char *) addr)[nr >> 3] |= (1U << (nr & 7));
+}
+
+extern void clear_bit(int nr, volatile void * addr);
+
+static inline void __clear_bit(int nr, volatile void *addr)
+{
+	((unsigned char *) addr)[nr >> 3] &= ~(1U << (nr & 7));
+}
+
+extern void change_bit(int nr, volatile void * addr);
+
+static inline void __change_bit(int nr, volatile void *addr)
+{
+	((unsigned char *) addr)[nr >> 3] ^= (1U << (nr & 7));
+}
+
+extern int test_and_set_bit(int nr, volatile void * addr);
+
+static inline int __test_and_set_bit(int nr, volatile void *addr)
+{
+	unsigned int mask = 1 << (nr & 7);
+	unsigned int oldval;
+
+	oldval = ((unsigned char *) addr)[nr >> 3];
+	((unsigned char *) addr)[nr >> 3] = oldval | mask;
+	return oldval & mask;
+}
+
+extern int test_and_clear_bit(int nr, volatile void * addr);
+
+static inline int __test_and_clear_bit(int nr, volatile void *addr)
+{
+	unsigned int mask = 1 << (nr & 7);
+	unsigned int oldval;
+
+	oldval = ((unsigned char *) addr)[nr >> 3];
+	((unsigned char *) addr)[nr >> 3] = oldval & ~mask;
+	return oldval & mask;
+}
+
+extern int test_and_change_bit(int nr, volatile void * addr);
+
+static inline int __test_and_change_bit(int nr, volatile void *addr)
+{
+	unsigned int mask = 1 << (nr & 7);
+	unsigned int oldval;
+
+	oldval = ((unsigned char *) addr)[nr >> 3];
+	((unsigned char *) addr)[nr >> 3] = oldval ^ mask;
+	return oldval & mask;
+}
+
+extern int find_first_zero_bit(void * addr, unsigned size);
+extern int find_next_zero_bit(void * addr, int size, int offset);
+
+/*
+ * This routine doesn't need to be atomic.
+ */
+static inline int test_bit(int nr, const void * addr)
+{
+    return ((unsigned char *) addr)[nr >> 3] & (1U << (nr & 7));
+}
+
+/*
+ * 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)
+{
+	int k;
+
+	word = ~word;
+	k = 31;
+	if (word & 0x0000ffff) { k -= 16; word <<= 16; }
+	if (word & 0x00ff0000) { k -= 8;  word <<= 8;  }
+	if (word & 0x0f000000) { k -= 4;  word <<= 4;  }
+	if (word & 0x30000000) { k -= 2;  word <<= 2;  }
+	if (word & 0x40000000) { k -= 1; }
+        return k;
+}
+
+/*
+ * ffs: find first bit set. This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+
+#define ffs(x) generic_ffs(x)
+
+/*
+ * 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			test_and_set_bit
+#define ext2_clear_bit			test_and_clear_bit
+#define ext2_test_bit			test_bit
+#define ext2_find_first_zero_bit	find_first_zero_bit
+#define ext2_find_next_zero_bit		find_next_zero_bit
+
+/* Bitmap functions for the minix filesystem. */
+#define minix_test_and_set_bit(nr,addr)	test_and_set_bit(nr,addr)
+#define minix_set_bit(nr,addr)		set_bit(nr,addr)
+#define minix_test_and_clear_bit(nr,addr)	test_and_clear_bit(nr,addr)
+#define minix_test_bit(nr,addr)		test_bit(nr,addr)
+#define minix_find_first_zero_bit(addr,size)	find_first_zero_bit(addr,size)
+
+#endif /* __KERNEL__ */
+
+#endif /* _ARM_BITOPS_H */