Initial revision

1 files changed, 333 insertions, 0 deletions

diff --git a/include/asm-ppc/bitops.h b/include/asm-ppc/bitops.h
new file mode 100644
index 000000000..5326686c8
--- /dev/null
+++ b/include/asm-ppc/bitops.h
@@ -0,0 +1,333 @@
+/*
+ * bitops.h: Bit string operations on the ppc
+ */
+
+#ifndef _PPC_BITOPS_H
+#define _PPC_BITOPS_H
+
+#include <linux/config.h>
+#include <asm/byteorder.h>
+
+extern void set_bit(int nr, volatile void *addr);
+extern void clear_bit(int nr, volatile void *addr);
+extern void change_bit(int nr, volatile void *addr);
+extern int test_and_set_bit(int nr, volatile void *addr);
+extern int test_and_clear_bit(int nr, volatile void *addr);
+extern int test_and_change_bit(int nr, volatile void *addr);
+
+/*
+ * Arguably these bit operations don't imply any memory barrier or
+ * SMP ordering, but in fact a lot of drivers expect them to imply
+ * both, since they do on x86 cpus.
+ */
+#ifdef CONFIG_SMP
+#define SMP_WMB		"eieio\n"
+#define SMP_MB		"\nsync"
+#else
+#define SMP_WMB
+#define SMP_MB
+#endif /* CONFIG_SMP */
+
+#define __INLINE_BITOPS	1
+
+#if __INLINE_BITOPS
+/*
+ * These used to be if'd out here because using : "cc" as a constraint
+ * resulted in errors from egcs.  Things may be OK with gcc-2.95.
+ */
+extern __inline__ void set_bit(int nr, volatile void * addr)
+{
+	unsigned long old;
+	unsigned long mask = 1 << (nr & 0x1f);
+	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%3\n\
+	or	%0,%0,%2\n\
+	stwcx.	%0,0,%3\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc" );
+}
+
+extern __inline__ void clear_bit(int nr, volatile void *addr)
+{
+	unsigned long old;
+	unsigned long mask = 1 << (nr & 0x1f);
+	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%3\n\
+	andc	%0,%0,%2\n\
+	stwcx.	%0,0,%3\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc");
+}
+
+extern __inline__ void change_bit(int nr, volatile void *addr)
+{
+	unsigned long old;
+	unsigned long mask = 1 << (nr & 0x1f);
+	unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%3\n\
+	xor	%0,%0,%2\n\
+	stwcx.	%0,0,%3\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc");
+}
+
+extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
+{
+	unsigned int old, t;
+	unsigned int mask = 1 << (nr & 0x1f);
+	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%4\n\
+	or	%1,%0,%3\n\
+	stwcx.	%1,0,%4\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=&r" (t), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc");
+
+	return (old & mask) != 0;
+}
+
+extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
+{
+	unsigned int old, t;
+	unsigned int mask = 1 << (nr & 0x1f);
+	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%4\n\
+	andc	%1,%0,%3\n\
+	stwcx.	%1,0,%4\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=&r" (t), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc");
+
+	return (old & mask) != 0;
+}
+
+extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
+{
+	unsigned int old, t;
+	unsigned int mask = 1 << (nr & 0x1f);
+	volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+	__asm__ __volatile__(SMP_WMB "\
+1:	lwarx	%0,0,%4\n\
+	xor	%1,%0,%3\n\
+	stwcx.	%1,0,%4\n\
+	bne	1b"
+	SMP_MB
+	: "=&r" (old), "=&r" (t), "=m" (*p)
+	: "r" (mask), "r" (p), "m" (*p)
+	: "cc");
+
+	return (old & mask) != 0;
+}
+#endif /* __INLINE_BITOPS */
+
+extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
+{
+	__const__ unsigned int *p = (__const__ unsigned int *) addr;
+
+	return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
+}
+
+/* Return the bit position of the most significant 1 bit in a word */
+extern __inline__ int __ilog2(unsigned int x)
+{
+	int lz;
+
+	asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
+	return 31 - lz;
+}
+
+extern __inline__ int ffz(unsigned int x)
+{
+	if ((x = ~x) == 0)
+		return 32;
+	return __ilog2(x & -x);
+}
+
+#ifdef __KERNEL__
+
+/*
+ * 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).
+ */
+extern __inline__ int ffs(int x)
+{
+	return __ilog2(x & -x) + 1;
+}
+
+/*
+ * 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)
+
+#endif /* __KERNEL__ */
+
+/*
+ * This implementation of find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h.
+ */
+#define find_first_zero_bit(addr, size) \
+	find_next_zero_bit((addr), (size), 0)
+
+extern __inline__ unsigned long find_next_zero_bit(void * addr,
+	unsigned long size, unsigned long offset)
+{
+	unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
+	unsigned int result = offset & ~31UL;
+	unsigned int 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 != ~0U)
+			goto found_middle;
+		size -= 32;
+		result += 32;
+	}
+	while (size >= 32) {
+		if ((tmp = *p++) != ~0U)
+			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 _EXT2_HAVE_ASM_BITOPS_
+
+#ifdef __KERNEL__
+/*
+ * test_and_{set,clear}_bit guarantee atomicity without
+ * disabling interrupts.
+ */
+#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)
+
+#else
+extern __inline__ int ext2_set_bit(int nr, void * addr)
+{
+	int		mask;
+	unsigned char	*ADDR = (unsigned char *) addr;
+	int oldbit;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	oldbit = (*ADDR & mask) ? 1 : 0;
+	*ADDR |= mask;
+	return oldbit;
+}
+
+extern __inline__ int ext2_clear_bit(int nr, void * addr)
+{
+	int		mask;
+	unsigned char	*ADDR = (unsigned char *) addr;
+	int oldbit;
+
+	ADDR += nr >> 3;
+	mask = 1 << (nr & 0x07);
+	oldbit = (*ADDR & mask) ? 1 : 0;
+	*ADDR = *ADDR & ~mask;
+	return oldbit;
+}
+#endif	/* __KERNEL__ */
+
+extern __inline__ int ext2_test_bit(int nr, __const__ void * addr)
+{
+	__const__ unsigned char	*ADDR = (__const__ unsigned char *) addr;
+
+	return (ADDR[nr >> 3] >> (nr & 7)) & 1;
+}
+
+/*
+ * This implementation of ext2_find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h and modified for a big-endian machine.
+ */
+
+#define ext2_find_first_zero_bit(addr, size) \
+        ext2_find_next_zero_bit((addr), (size), 0)
+
+extern __inline__ unsigned long ext2_find_next_zero_bit(void *addr,
+	unsigned long size, unsigned long offset)
+{
+	unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
+	unsigned int result = offset & ~31UL;
+	unsigned int tmp;
+
+	if (offset >= size)
+		return size;
+	size -= result;
+	offset &= 31UL;
+	if (offset) {
+		tmp = cpu_to_le32p(p++);
+		tmp |= ~0UL >> (32-offset);
+		if (size < 32)
+			goto found_first;
+		if (tmp != ~0U)
+			goto found_middle;
+		size -= 32;
+		result += 32;
+	}
+	while (size >= 32) {
+		if ((tmp = cpu_to_le32p(p++)) != ~0U)
+			goto found_middle;
+		result += 32;
+		size -= 32;
+	}
+	if (!size)
+		return result;
+	tmp = cpu_to_le32p(p);
+found_first:
+	tmp |= ~0U << size;
+found_middle:
+	return result + ffz(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) ((void)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 /* _PPC_BITOPS_H */