1 files changed, 275 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/bitops.h b/arch/powerpc/include/asm/bitops.h
new file mode 100644
index 000000000..299ab3350
--- /dev/null
+++ b/arch/powerpc/include/asm/bitops.h
@@ -0,0 +1,275 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * PowerPC atomic bit operations.
+ *
+ * Merged version by David Gibson <david@gibson.dropbear.id.au>.
+ * Based on ppc64 versions by: Dave Engebretsen, Todd Inglett, Don
+ * Reed, Pat McCarthy, Peter Bergner, Anton Blanchard.  They
+ * originally took it from the ppc32 code.
+ *
+ * Within a word, bits are numbered LSB first.  Lot's of places make
+ * this assumption by directly testing bits with (val & (1<<nr)).
+ * This can cause confusion for large (> 1 word) bitmaps on a
+ * big-endian system because, unlike little endian, the number of each
+ * bit depends on the word size.
+ *
+ * The bitop functions are defined to work on unsigned longs, so for a
+ * ppc64 system the bits end up numbered:
+ *   |63..............0|127............64|191...........128|255...........192|
+ * and on ppc32:
+ *   |31.....0|63....32|95....64|127...96|159..128|191..160|223..192|255..224|
+ *
+ * There are a few little-endian macros used mostly for filesystem
+ * bitmaps, these work on similar bit arrays layouts, but
+ * byte-oriented:
+ *   |7...0|15...8|23...16|31...24|39...32|47...40|55...48|63...56|
+ *
+ * The main difference is that bit 3-5 (64b) or 3-4 (32b) in the bit
+ * number field needs to be reversed compared to the big-endian bit
+ * fields. This can be achieved by XOR with 0x38 (64b) or 0x18 (32b).
+ */
+
+#ifndef _ASM_POWERPC_BITOPS_H
+#define _ASM_POWERPC_BITOPS_H
+
+#ifdef __KERNEL__
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <linux/compiler.h>
+#include <asm/asm-compat.h>
+#include <asm/synch.h>
+
+/* PPC bit number conversion */
+#define PPC_BITLSHIFT(be)	(BITS_PER_LONG - 1 - (be))
+#define PPC_BIT(bit)		(1UL << PPC_BITLSHIFT(bit))
+#define PPC_BITMASK(bs, be)	((PPC_BIT(bs) - PPC_BIT(be)) | PPC_BIT(bs))
+
+/* Put a PPC bit into a "normal" bit position */
+#define PPC_BITEXTRACT(bits, ppc_bit, dst_bit)			\
+	((((bits) >> PPC_BITLSHIFT(ppc_bit)) & 1) << (dst_bit))
+
+#define PPC_BITLSHIFT32(be)	(32 - 1 - (be))
+#define PPC_BIT32(bit)		(1UL << PPC_BITLSHIFT32(bit))
+#define PPC_BITMASK32(bs, be)	((PPC_BIT32(bs) - PPC_BIT32(be))|PPC_BIT32(bs))
+
+#define PPC_BITLSHIFT8(be)	(8 - 1 - (be))
+#define PPC_BIT8(bit)		(1UL << PPC_BITLSHIFT8(bit))
+#define PPC_BITMASK8(bs, be)	((PPC_BIT8(bs) - PPC_BIT8(be))|PPC_BIT8(bs))
+
+#include <asm/barrier.h>
+
+/* Macro for generating the ***_bits() functions */
+#define DEFINE_BITOP(fn, op, prefix)		\
+static inline void fn(unsigned long mask,	\
+		volatile unsigned long *_p)	\
+{						\
+	unsigned long old;			\
+	unsigned long *p = (unsigned long *)_p;	\
+	__asm__ __volatile__ (			\
+	prefix					\
+"1:"	PPC_LLARX(%0,0,%3,0) "\n"		\
+	stringify_in_c(op) "%0,%0,%2\n"		\
+	PPC_STLCX "%0,0,%3\n"			\
+	"bne- 1b\n"				\
+	: "=&r" (old), "+m" (*p)		\
+	: "r" (mask), "r" (p)			\
+	: "cc", "memory");			\
+}
+
+DEFINE_BITOP(set_bits, or, "")
+DEFINE_BITOP(clear_bits, andc, "")
+DEFINE_BITOP(clear_bits_unlock, andc, PPC_RELEASE_BARRIER)
+DEFINE_BITOP(change_bits, xor, "")
+
+static inline void arch_set_bit(int nr, volatile unsigned long *addr)
+{
+	set_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
+}
+
+static inline void arch_clear_bit(int nr, volatile unsigned long *addr)
+{
+	clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
+}
+
+static inline void arch_clear_bit_unlock(int nr, volatile unsigned long *addr)
+{
+	clear_bits_unlock(BIT_MASK(nr), addr + BIT_WORD(nr));
+}
+
+static inline void arch_change_bit(int nr, volatile unsigned long *addr)
+{
+	change_bits(BIT_MASK(nr), addr + BIT_WORD(nr));
+}
+
+/* Like DEFINE_BITOP(), with changes to the arguments to 'op' and the output
+ * operands. */
+#define DEFINE_TESTOP(fn, op, prefix, postfix, eh)	\
+static inline unsigned long fn(			\
+		unsigned long mask,			\
+		volatile unsigned long *_p)		\
+{							\
+	unsigned long old, t;				\
+	unsigned long *p = (unsigned long *)_p;		\
+	__asm__ __volatile__ (				\
+	prefix						\
+"1:"	PPC_LLARX(%0,0,%3,eh) "\n"			\
+	stringify_in_c(op) "%1,%0,%2\n"			\
+	PPC_STLCX "%1,0,%3\n"				\
+	"bne- 1b\n"					\
+	postfix						\
+	: "=&r" (old), "=&r" (t)			\
+	: "r" (mask), "r" (p)				\
+	: "cc", "memory");				\
+	return (old & mask);				\
+}
+
+DEFINE_TESTOP(test_and_set_bits, or, PPC_ATOMIC_ENTRY_BARRIER,
+	      PPC_ATOMIC_EXIT_BARRIER, 0)
+DEFINE_TESTOP(test_and_set_bits_lock, or, "",
+	      PPC_ACQUIRE_BARRIER, 1)
+DEFINE_TESTOP(test_and_clear_bits, andc, PPC_ATOMIC_ENTRY_BARRIER,
+	      PPC_ATOMIC_EXIT_BARRIER, 0)
+DEFINE_TESTOP(test_and_change_bits, xor, PPC_ATOMIC_ENTRY_BARRIER,
+	      PPC_ATOMIC_EXIT_BARRIER, 0)
+
+static inline int arch_test_and_set_bit(unsigned long nr,
+					volatile unsigned long *addr)
+{
+	return test_and_set_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
+}
+
+static inline int arch_test_and_set_bit_lock(unsigned long nr,
+					     volatile unsigned long *addr)
+{
+	return test_and_set_bits_lock(BIT_MASK(nr),
+				addr + BIT_WORD(nr)) != 0;
+}
+
+static inline int arch_test_and_clear_bit(unsigned long nr,
+					  volatile unsigned long *addr)
+{
+	return test_and_clear_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
+}
+
+static inline int arch_test_and_change_bit(unsigned long nr,
+					   volatile unsigned long *addr)
+{
+	return test_and_change_bits(BIT_MASK(nr), addr + BIT_WORD(nr)) != 0;
+}
+
+#ifdef CONFIG_PPC64
+static inline unsigned long
+clear_bit_unlock_return_word(int nr, volatile unsigned long *addr)
+{
+	unsigned long old, t;
+	unsigned long *p = (unsigned long *)addr + BIT_WORD(nr);
+	unsigned long mask = BIT_MASK(nr);
+
+	__asm__ __volatile__ (
+	PPC_RELEASE_BARRIER
+"1:"	PPC_LLARX(%0,0,%3,0) "\n"
+	"andc %1,%0,%2\n"
+	PPC_STLCX "%1,0,%3\n"
+	"bne- 1b\n"
+	: "=&r" (old), "=&r" (t)
+	: "r" (mask), "r" (p)
+	: "cc", "memory");
+
+	return old;
+}
+
+/*
+ * This is a special function for mm/filemap.c
+ * Bit 7 corresponds to PG_waiters.
+ */
+#define arch_clear_bit_unlock_is_negative_byte(nr, addr)		\
+	(clear_bit_unlock_return_word(nr, addr) & BIT_MASK(7))
+
+#endif /* CONFIG_PPC64 */
+
+#include <asm-generic/bitops/non-atomic.h>
+
+static inline void arch___clear_bit_unlock(int nr, volatile unsigned long *addr)
+{
+	__asm__ __volatile__(PPC_RELEASE_BARRIER "" ::: "memory");
+	__clear_bit(nr, addr);
+}
+
+/*
+ * Return the zero-based bit position (LE, not IBM bit numbering) of
+ * the most significant 1-bit in a double word.
+ */
+#define __ilog2(x)	ilog2(x)
+
+#include <asm-generic/bitops/ffz.h>
+
+#include <asm-generic/bitops/builtin-__ffs.h>
+
+#include <asm-generic/bitops/builtin-ffs.h>
+
+/*
+ * fls: find last (most-significant) bit set.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+static inline int fls(unsigned int x)
+{
+	int lz;
+
+	if (__builtin_constant_p(x))
+		return x ? 32 - __builtin_clz(x) : 0;
+	asm("cntlzw %0,%1" : "=r" (lz) : "r" (x));
+	return 32 - lz;
+}
+
+#include <asm-generic/bitops/builtin-__fls.h>
+
+/*
+ * 64-bit can do this using one cntlzd (count leading zeroes doubleword)
+ * instruction; for 32-bit we use the generic version, which does two
+ * 32-bit fls calls.
+ */
+#ifdef CONFIG_PPC64
+static inline int fls64(__u64 x)
+{
+	int lz;
+
+	if (__builtin_constant_p(x))
+		return x ? 64 - __builtin_clzll(x) : 0;
+	asm("cntlzd %0,%1" : "=r" (lz) : "r" (x));
+	return 64 - lz;
+}
+#else
+#include <asm-generic/bitops/fls64.h>
+#endif
+
+#ifdef CONFIG_PPC64
+unsigned int __arch_hweight8(unsigned int w);
+unsigned int __arch_hweight16(unsigned int w);
+unsigned int __arch_hweight32(unsigned int w);
+unsigned long __arch_hweight64(__u64 w);
+#include <asm-generic/bitops/const_hweight.h>
+#else
+#include <asm-generic/bitops/hweight.h>
+#endif
+
+#include <asm-generic/bitops/find.h>
+
+/* wrappers that deal with KASAN instrumentation */
+#include <asm-generic/bitops/instrumented-atomic.h>
+#include <asm-generic/bitops/instrumented-lock.h>
+
+/* Little-endian versions */
+#include <asm-generic/bitops/le.h>
+
+/* Bitmap functions for the ext2 filesystem */
+
+#include <asm-generic/bitops/ext2-atomic-setbit.h>
+
+#include <asm-generic/bitops/sched.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_POWERPC_BITOPS_H */