v4.19.13 snapshot.
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
new file mode 100644
index 0000000..da1b871
--- /dev/null
+++ b/arch/mips/include/asm/bitops.h
@@ -0,0 +1,620 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1994 - 1997, 99, 2000, 06, 07  Ralf Baechle (ralf@linux-mips.org)
+ * Copyright (c) 1999, 2000  Silicon Graphics, Inc.
+ */
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#ifndef _LINUX_BITOPS_H
+#error only <linux/bitops.h> can be included directly
+#endif
+
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/barrier.h>
+#include <asm/byteorder.h>		/* sigh ... */
+#include <asm/compiler.h>
+#include <asm/cpu-features.h>
+#include <asm/llsc.h>
+#include <asm/sgidefs.h>
+#include <asm/war.h>
+
+/*
+ * These are the "slower" versions of the functions and are in bitops.c.
+ * These functions call raw_local_irq_{save,restore}().
+ */
+void __mips_set_bit(unsigned long nr, volatile unsigned long *addr);
+void __mips_clear_bit(unsigned long nr, volatile unsigned long *addr);
+void __mips_change_bit(unsigned long nr, volatile unsigned long *addr);
+int __mips_test_and_set_bit(unsigned long nr,
+			    volatile unsigned long *addr);
+int __mips_test_and_set_bit_lock(unsigned long nr,
+				 volatile unsigned long *addr);
+int __mips_test_and_clear_bit(unsigned long nr,
+			      volatile unsigned long *addr);
+int __mips_test_and_change_bit(unsigned long nr,
+			       volatile unsigned long *addr);
+
+
+/*
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered.  See __set_bit()
+ * if you do not require the atomic guarantees.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
+{
+	unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+	int bit = nr & SZLONG_MASK;
+	unsigned long temp;
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL "%0, %1			# set_bit	\n"
+		"	or	%0, %2					\n"
+		"	" __SC	"%0, %1					\n"
+		"	beqzl	%0, 1b					\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "=" GCC_OFF_SMALL_ASM() (*m)
+		: "ir" (1UL << bit), GCC_OFF_SMALL_ASM() (*m));
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
+	} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
+		do {
+			__asm__ __volatile__(
+			"	" __LL "%0, %1		# set_bit	\n"
+			"	" __INS "%0, %3, %2, 1			\n"
+			"	" __SC "%0, %1				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (bit), "r" (~0));
+		} while (unlikely(!temp));
+#endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
+	} else if (kernel_uses_llsc) {
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL "%0, %1		# set_bit	\n"
+			"	or	%0, %2				\n"
+			"	" __SC	"%0, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (1UL << bit));
+		} while (unlikely(!temp));
+	} else
+		__mips_set_bit(nr, addr);
+}
+
+/*
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and may not be reordered.  However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_atomic() and/or smp_mb__after_atomic()
+ * in order to ensure changes are visible on other processors.
+ */
+static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
+{
+	unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+	int bit = nr & SZLONG_MASK;
+	unsigned long temp;
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL "%0, %1			# clear_bit	\n"
+		"	and	%0, %2					\n"
+		"	" __SC "%0, %1					\n"
+		"	beqzl	%0, 1b					\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+		: "ir" (~(1UL << bit)));
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
+	} else if (kernel_uses_llsc && __builtin_constant_p(bit)) {
+		do {
+			__asm__ __volatile__(
+			"	" __LL "%0, %1		# clear_bit	\n"
+			"	" __INS "%0, $0, %2, 1			\n"
+			"	" __SC "%0, %1				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (bit));
+		} while (unlikely(!temp));
+#endif /* CONFIG_CPU_MIPSR2 || CONFIG_CPU_MIPSR6 */
+	} else if (kernel_uses_llsc) {
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL "%0, %1		# clear_bit	\n"
+			"	and	%0, %2				\n"
+			"	" __SC "%0, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (~(1UL << bit)));
+		} while (unlikely(!temp));
+	} else
+		__mips_clear_bit(nr, addr);
+}
+
+/*
+ * clear_bit_unlock - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and implies release semantics before the memory
+ * operation. It can be used for an unlock.
+ */
+static inline void clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
+{
+	smp_mb__before_atomic();
+	clear_bit(nr, addr);
+}
+
+/*
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static inline void change_bit(unsigned long nr, volatile unsigned long *addr)
+{
+	int bit = nr & SZLONG_MASK;
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	arch=r4000			\n"
+		"1:	" __LL "%0, %1		# change_bit	\n"
+		"	xor	%0, %2				\n"
+		"	" __SC	"%0, %1				\n"
+		"	beqzl	%0, 1b				\n"
+		"	.set	mips0				\n"
+		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+		: "ir" (1UL << bit));
+	} else if (kernel_uses_llsc) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL "%0, %1		# change_bit	\n"
+			"	xor	%0, %2				\n"
+			"	" __SC	"%0, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m)
+			: "ir" (1UL << bit));
+		} while (unlikely(!temp));
+	} else
+		__mips_change_bit(nr, addr);
+}
+
+/*
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_set_bit(unsigned long nr,
+	volatile unsigned long *addr)
+{
+	int bit = nr & SZLONG_MASK;
+	unsigned long res;
+
+	smp_mb__before_llsc();
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL "%0, %1		# test_and_set_bit	\n"
+		"	or	%2, %0, %3				\n"
+		"	" __SC	"%2, %1					\n"
+		"	beqzl	%2, 1b					\n"
+		"	and	%2, %0, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+		: "r" (1UL << bit)
+		: "memory");
+	} else if (kernel_uses_llsc) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL "%0, %1	# test_and_set_bit	\n"
+			"	or	%2, %0, %3			\n"
+			"	" __SC	"%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
+	} else
+		res = __mips_test_and_set_bit(nr, addr);
+
+	smp_llsc_mb();
+
+	return res != 0;
+}
+
+/*
+ * test_and_set_bit_lock - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and implies acquire ordering semantics
+ * after the memory operation.
+ */
+static inline int test_and_set_bit_lock(unsigned long nr,
+	volatile unsigned long *addr)
+{
+	int bit = nr & SZLONG_MASK;
+	unsigned long res;
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL "%0, %1		# test_and_set_bit	\n"
+		"	or	%2, %0, %3				\n"
+		"	" __SC	"%2, %1					\n"
+		"	beqzl	%2, 1b					\n"
+		"	and	%2, %0, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "+m" (*m), "=&r" (res)
+		: "r" (1UL << bit)
+		: "memory");
+	} else if (kernel_uses_llsc) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL "%0, %1	# test_and_set_bit	\n"
+			"	or	%2, %0, %3			\n"
+			"	" __SC	"%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
+	} else
+		res = __mips_test_and_set_bit_lock(nr, addr);
+
+	smp_llsc_mb();
+
+	return res != 0;
+}
+/*
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_clear_bit(unsigned long nr,
+	volatile unsigned long *addr)
+{
+	int bit = nr & SZLONG_MASK;
+	unsigned long res;
+
+	smp_mb__before_llsc();
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL	"%0, %1		# test_and_clear_bit	\n"
+		"	or	%2, %0, %3				\n"
+		"	xor	%2, %3					\n"
+		"	" __SC	"%2, %1					\n"
+		"	beqzl	%2, 1b					\n"
+		"	and	%2, %0, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+		: "r" (1UL << bit)
+		: "memory");
+#if defined(CONFIG_CPU_MIPSR2) || defined(CONFIG_CPU_MIPSR6)
+	} else if (kernel_uses_llsc && __builtin_constant_p(nr)) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+			"	" __EXT "%2, %0, %3, 1			\n"
+			"	" __INS "%0, $0, %3, 1			\n"
+			"	" __SC	"%0, %1				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "ir" (bit)
+			: "memory");
+		} while (unlikely(!temp));
+#endif
+	} else if (kernel_uses_llsc) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL	"%0, %1 # test_and_clear_bit	\n"
+			"	or	%2, %0, %3			\n"
+			"	xor	%2, %3				\n"
+			"	" __SC	"%2, %1				\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
+	} else
+		res = __mips_test_and_clear_bit(nr, addr);
+
+	smp_llsc_mb();
+
+	return res != 0;
+}
+
+/*
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_change_bit(unsigned long nr,
+	volatile unsigned long *addr)
+{
+	int bit = nr & SZLONG_MASK;
+	unsigned long res;
+
+	smp_mb__before_llsc();
+
+	if (kernel_uses_llsc && R10000_LLSC_WAR) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		__asm__ __volatile__(
+		"	.set	arch=r4000				\n"
+		"1:	" __LL	"%0, %1		# test_and_change_bit	\n"
+		"	xor	%2, %0, %3				\n"
+		"	" __SC	"%2, %1					\n"
+		"	beqzl	%2, 1b					\n"
+		"	and	%2, %0, %3				\n"
+		"	.set	mips0					\n"
+		: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+		: "r" (1UL << bit)
+		: "memory");
+	} else if (kernel_uses_llsc) {
+		unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+		unsigned long temp;
+
+		do {
+			__asm__ __volatile__(
+			"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
+			"	" __LL	"%0, %1 # test_and_change_bit	\n"
+			"	xor	%2, %0, %3			\n"
+			"	" __SC	"\t%2, %1			\n"
+			"	.set	mips0				\n"
+			: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (*m), "=&r" (res)
+			: "r" (1UL << bit)
+			: "memory");
+		} while (unlikely(!res));
+
+		res = temp & (1UL << bit);
+	} else
+		res = __mips_test_and_change_bit(nr, addr);
+
+	smp_llsc_mb();
+
+	return res != 0;
+}
+
+#include <asm-generic/bitops/non-atomic.h>
+
+/*
+ * __clear_bit_unlock - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * __clear_bit() is non-atomic and implies release semantics before the memory
+ * operation. It can be used for an unlock if no other CPUs can concurrently
+ * modify other bits in the word.
+ */
+static inline void __clear_bit_unlock(unsigned long nr, volatile unsigned long *addr)
+{
+	smp_mb__before_llsc();
+	__clear_bit(nr, addr);
+	nudge_writes();
+}
+
+/*
+ * Return the bit position (0..63) of the most significant 1 bit in a word
+ * Returns -1 if no 1 bit exists
+ */
+static inline unsigned long __fls(unsigned long word)
+{
+	int num;
+
+	if (BITS_PER_LONG == 32 && !__builtin_constant_p(word) &&
+	    __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
+		__asm__(
+		"	.set	push					\n"
+		"	.set	"MIPS_ISA_LEVEL"			\n"
+		"	clz	%0, %1					\n"
+		"	.set	pop					\n"
+		: "=r" (num)
+		: "r" (word));
+
+		return 31 - num;
+	}
+
+	if (BITS_PER_LONG == 64 && !__builtin_constant_p(word) &&
+	    __builtin_constant_p(cpu_has_mips64) && cpu_has_mips64) {
+		__asm__(
+		"	.set	push					\n"
+		"	.set	"MIPS_ISA_LEVEL"			\n"
+		"	dclz	%0, %1					\n"
+		"	.set	pop					\n"
+		: "=r" (num)
+		: "r" (word));
+
+		return 63 - num;
+	}
+
+	num = BITS_PER_LONG - 1;
+
+#if BITS_PER_LONG == 64
+	if (!(word & (~0ul << 32))) {
+		num -= 32;
+		word <<= 32;
+	}
+#endif
+	if (!(word & (~0ul << (BITS_PER_LONG-16)))) {
+		num -= 16;
+		word <<= 16;
+	}
+	if (!(word & (~0ul << (BITS_PER_LONG-8)))) {
+		num -= 8;
+		word <<= 8;
+	}
+	if (!(word & (~0ul << (BITS_PER_LONG-4)))) {
+		num -= 4;
+		word <<= 4;
+	}
+	if (!(word & (~0ul << (BITS_PER_LONG-2)))) {
+		num -= 2;
+		word <<= 2;
+	}
+	if (!(word & (~0ul << (BITS_PER_LONG-1))))
+		num -= 1;
+	return num;
+}
+
+/*
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Returns 0..SZLONG-1
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static inline unsigned long __ffs(unsigned long word)
+{
+	return __fls(word & -word);
+}
+
+/*
+ * fls - find last bit set.
+ * @word: The word to search
+ *
+ * This is defined the same way as ffs.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ */
+static inline int fls(int x)
+{
+	int r;
+
+	if (!__builtin_constant_p(x) &&
+	    __builtin_constant_p(cpu_has_clo_clz) && cpu_has_clo_clz) {
+		__asm__(
+		"	.set	push					\n"
+		"	.set	"MIPS_ISA_LEVEL"			\n"
+		"	clz	%0, %1					\n"
+		"	.set	pop					\n"
+		: "=r" (x)
+		: "r" (x));
+
+		return 32 - x;
+	}
+
+	r = 32;
+	if (!x)
+		return 0;
+	if (!(x & 0xffff0000u)) {
+		x <<= 16;
+		r -= 16;
+	}
+	if (!(x & 0xff000000u)) {
+		x <<= 8;
+		r -= 8;
+	}
+	if (!(x & 0xf0000000u)) {
+		x <<= 4;
+		r -= 4;
+	}
+	if (!(x & 0xc0000000u)) {
+		x <<= 2;
+		r -= 2;
+	}
+	if (!(x & 0x80000000u)) {
+		x <<= 1;
+		r -= 1;
+	}
+	return r;
+}
+
+#include <asm-generic/bitops/fls64.h>
+
+/*
+ * ffs - find first bit set.
+ * @word: The word to search
+ *
+ * This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+static inline int ffs(int word)
+{
+	if (!word)
+		return 0;
+
+	return fls(word & -word);
+}
+
+#include <asm-generic/bitops/ffz.h>
+#include <asm-generic/bitops/find.h>
+
+#ifdef __KERNEL__
+
+#include <asm-generic/bitops/sched.h>
+
+#include <asm/arch_hweight.h>
+#include <asm-generic/bitops/const_hweight.h>
+
+#include <asm-generic/bitops/le.h>
+#include <asm-generic/bitops/ext2-atomic.h>
+
+#endif /* __KERNEL__ */
+
+#endif /* _ASM_BITOPS_H */