arch/hexagon/include/asm/bitops.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-only */
 /*
  * Bit operations for the Hexagon architecture
  *
  * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
  */

 #ifndef _ASM_BITOPS_H
 #define _ASM_BITOPS_H

 #include <linux/compiler.h>
 #include <asm/byteorder.h>
 #include <asm/atomic.h>
 #include <asm/barrier.h>

 #ifdef __KERNEL__

 /*
  * The offset calculations for these are based on BITS_PER_LONG == 32
  * (i.e. I get to shift by #5-2 (32 bits per long, 4 bytes per access),
  * mask by 0x0000001F)
  *
  * Typically, R10 is clobbered for address, R11 bit nr, and R12 is temp
  */

 /**
  * test_and_clear_bit - clear a bit and return its old value
  * @nr:  bit number to clear
  * @addr:  pointer to memory
  */
 static inline int test_and_clear_bit(int nr, volatile void *addr)
 {
 	int oldval;

 	__asm__ __volatile__ (
 	"	{R10 = %1; R11 = asr(%2,#5); }\n"
 	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
 	"1:	R12 = memw_locked(R10);\n"
 	"	{ P0 = tstbit(R12,R11); R12 = clrbit(R12,R11); }\n"
 	"	memw_locked(R10,P1) = R12;\n"
 	"	{if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
 	: "=&r" (oldval)
 	: "r" (addr), "r" (nr)
 	: "r10", "r11", "r12", "p0", "p1", "memory"
 	);

 	return oldval;
 }

 /**
  * test_and_set_bit - set a bit and return its old value
  * @nr:  bit number to set
  * @addr:  pointer to memory
  */
 static inline int test_and_set_bit(int nr, volatile void *addr)
 {
 	int oldval;

 	__asm__ __volatile__ (
 	"	{R10 = %1; R11 = asr(%2,#5); }\n"
 	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
 	"1:	R12 = memw_locked(R10);\n"
 	"	{ P0 = tstbit(R12,R11); R12 = setbit(R12,R11); }\n"
 	"	memw_locked(R10,P1) = R12;\n"
 	"	{if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
 	: "=&r" (oldval)
 	: "r" (addr), "r" (nr)
 	: "r10", "r11", "r12", "p0", "p1", "memory"
 	);


 	return oldval;

 }

 /**
  * test_and_change_bit - toggle a bit and return its old value
  * @nr:  bit number to set
  * @addr:  pointer to memory
  */
 static inline int test_and_change_bit(int nr, volatile void *addr)
 {
 	int oldval;

 	__asm__ __volatile__ (
 	"	{R10 = %1; R11 = asr(%2,#5); }\n"
 	"	{R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
 	"1:	R12 = memw_locked(R10);\n"
 	"	{ P0 = tstbit(R12,R11); R12 = togglebit(R12,R11); }\n"
 	"	memw_locked(R10,P1) = R12;\n"
 	"	{if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
 	: "=&r" (oldval)
 	: "r" (addr), "r" (nr)
 	: "r10", "r11", "r12", "p0", "p1", "memory"
 	);

 	return oldval;

 }

 /*
  * Atomic, but doesn't care about the return value.
  * Rewrite later to save a cycle or two.
  */

 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);
 }


 /*
  * These are allowed to be non-atomic.  In fact the generic flavors are
  * in non-atomic.h.  Would it be better to use intrinsics for this?
  *
  * OK, writes in our architecture do not invalidate LL/SC, so this has to
  * be atomic, particularly for things like slab_lock and slab_unlock.
  *
  */
 static __always_inline void
 arch___clear_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	test_and_clear_bit(nr, addr);
 }

 static __always_inline void
 arch___set_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	test_and_set_bit(nr, addr);
 }

 static __always_inline void
 arch___change_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	test_and_change_bit(nr, addr);
 }

 /*  Apparently, at least some of these are allowed to be non-atomic  */
 static __always_inline bool
 arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	return test_and_clear_bit(nr, addr);
 }

 static __always_inline bool
 arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	return test_and_set_bit(nr, addr);
 }

 static __always_inline bool
 arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
 {
 	return test_and_change_bit(nr, addr);
 }

 static __always_inline bool
 arch_test_bit(unsigned long nr, const volatile unsigned long *addr)
 {
 	int retval;

 	asm volatile(
 	"{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
 	: "=&r" (retval)
 	: "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
 	: "p0"
 	);

 	return retval;
 }

 static __always_inline bool
 arch_test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
 {
 	int retval;

 	asm volatile(
 	"{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
 	: "=&r" (retval)
 	: "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
 	: "p0", "memory"
 	);

 	return retval;
 }

 /*
  * ffz - find first zero in word.
  * @word: The word to search
  *
  * Undefined if no zero exists, so code should check against ~0UL first.
  */
 static inline long ffz(int x)
 {
 	int r;

 	asm("%0 = ct1(%1);\n"
 		: "=&r" (r)
 		: "r" (x));
 	return r;
 }

 /*
  * fls - find last (most-significant) bit set
  * @x: 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(unsigned int x)
 {
 	int r;

 	asm("{ %0 = cl0(%1);}\n"
 		"%0 = sub(#32,%0);\n"
 		: "=&r" (r)
 		: "r" (x)
 		: "p0");

 	return r;
 }

 /*
  * ffs - find first bit set
  * @x: 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 x)
 {
 	int r;

 	asm("{ P0 = cmp.eq(%1,#0); %0 = ct0(%1);}\n"
 		"{ if (P0) %0 = #0; if (!P0) %0 = add(%0,#1);}\n"
 		: "=&r" (r)
 		: "r" (x)
 		: "p0");

 	return r;
 }

 /*
  * __ffs - find first bit in word.
  * @word: The word to search
  *
  * Undefined if no bit exists, so code should check against 0 first.
  *
  * bits_per_long assumed to be 32
  * numbering starts at 0 I think (instead of 1 like ffs)
  */
 static inline unsigned long __ffs(unsigned long word)
 {
 	int num;

 	asm("%0 = ct0(%1);\n"
 		: "=&r" (num)
 		: "r" (word));

 	return num;
 }

 /*
  * __fls - find last (most-significant) set bit in a long word
  * @word: the word to search
  *
  * Undefined if no set bit exists, so code should check against 0 first.
  * bits_per_long assumed to be 32
  */
 static inline unsigned long __fls(unsigned long word)
 {
 	int num;

 	asm("%0 = cl0(%1);\n"
 		"%0 = sub(#31,%0);\n"
 		: "=&r" (num)
 		: "r" (word));

 	return num;
 }

 #include <asm-generic/bitops/lock.h>
 #include <asm-generic/bitops/non-instrumented-non-atomic.h>

 #include <asm-generic/bitops/fls64.h>
 #include <asm-generic/bitops/sched.h>
 #include <asm-generic/bitops/hweight.h>

 #include <asm-generic/bitops/le.h>
 #include <asm-generic/bitops/ext2-atomic.h>

 #endif /* __KERNEL__ */
 #endif
	/* SPDX-License-Identifier: GPL-2.0-only */
	/*
	* Bit operations for the Hexagon architecture
	*
	* Copyright (c) 2010-2011, The Linux Foundation. All rights reserved.
	*/

	#ifndef _ASM_BITOPS_H
	#define _ASM_BITOPS_H

	#include <linux/compiler.h>
	#include <asm/byteorder.h>
	#include <asm/atomic.h>
	#include <asm/barrier.h>

	#ifdef __KERNEL__

	/*
	* The offset calculations for these are based on BITS_PER_LONG == 32
	* (i.e. I get to shift by #5-2 (32 bits per long, 4 bytes per access),
	* mask by 0x0000001F)
	*
	* Typically, R10 is clobbered for address, R11 bit nr, and R12 is temp
	*/

	/**
	* test_and_clear_bit - clear a bit and return its old value
	* @nr: bit number to clear
	* @addr: pointer to memory
	*/
	static inline int test_and_clear_bit(int nr, volatile void *addr)
	{
	int oldval;

	__asm__ __volatile__ (
	" {R10 = %1; R11 = asr(%2,#5); }\n"
	" {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
	"1: R12 = memw_locked(R10);\n"
	" { P0 = tstbit(R12,R11); R12 = clrbit(R12,R11); }\n"
	" memw_locked(R10,P1) = R12;\n"
	" {if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
	: "=&r" (oldval)
	: "r" (addr), "r" (nr)
	: "r10", "r11", "r12", "p0", "p1", "memory"
	);

	return oldval;
	}

	/**
	* test_and_set_bit - set a bit and return its old value
	* @nr: bit number to set
	* @addr: pointer to memory
	*/
	static inline int test_and_set_bit(int nr, volatile void *addr)
	{
	int oldval;

	__asm__ __volatile__ (
	" {R10 = %1; R11 = asr(%2,#5); }\n"
	" {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
	"1: R12 = memw_locked(R10);\n"
	" { P0 = tstbit(R12,R11); R12 = setbit(R12,R11); }\n"
	" memw_locked(R10,P1) = R12;\n"
	" {if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
	: "=&r" (oldval)
	: "r" (addr), "r" (nr)
	: "r10", "r11", "r12", "p0", "p1", "memory"
	);


	return oldval;

	}

	/**
	* test_and_change_bit - toggle a bit and return its old value
	* @nr: bit number to set
	* @addr: pointer to memory
	*/
	static inline int test_and_change_bit(int nr, volatile void *addr)
	{
	int oldval;

	__asm__ __volatile__ (
	" {R10 = %1; R11 = asr(%2,#5); }\n"
	" {R10 += asl(R11,#2); R11 = and(%2,#0x1f)}\n"
	"1: R12 = memw_locked(R10);\n"
	" { P0 = tstbit(R12,R11); R12 = togglebit(R12,R11); }\n"
	" memw_locked(R10,P1) = R12;\n"
	" {if (!P1) jump 1b; %0 = mux(P0,#1,#0);}\n"
	: "=&r" (oldval)
	: "r" (addr), "r" (nr)
	: "r10", "r11", "r12", "p0", "p1", "memory"
	);

	return oldval;

	}

	/*
	* Atomic, but doesn't care about the return value.
	* Rewrite later to save a cycle or two.
	*/

	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);
	}


	/*
	* These are allowed to be non-atomic. In fact the generic flavors are
	* in non-atomic.h. Would it be better to use intrinsics for this?
	*
	* OK, writes in our architecture do not invalidate LL/SC, so this has to
	* be atomic, particularly for things like slab_lock and slab_unlock.
	*
	*/
	static __always_inline void
	arch___clear_bit(unsigned long nr, volatile unsigned long *addr)
	{
	test_and_clear_bit(nr, addr);
	}

	static __always_inline void
	arch___set_bit(unsigned long nr, volatile unsigned long *addr)
	{
	test_and_set_bit(nr, addr);
	}

	static __always_inline void
	arch___change_bit(unsigned long nr, volatile unsigned long *addr)
	{
	test_and_change_bit(nr, addr);
	}

	/* Apparently, at least some of these are allowed to be non-atomic */
	static __always_inline bool
	arch___test_and_clear_bit(unsigned long nr, volatile unsigned long *addr)
	{
	return test_and_clear_bit(nr, addr);
	}

	static __always_inline bool
	arch___test_and_set_bit(unsigned long nr, volatile unsigned long *addr)
	{
	return test_and_set_bit(nr, addr);
	}

	static __always_inline bool
	arch___test_and_change_bit(unsigned long nr, volatile unsigned long *addr)
	{
	return test_and_change_bit(nr, addr);
	}

	static __always_inline bool
	arch_test_bit(unsigned long nr, const volatile unsigned long *addr)
	{
	int retval;

	asm volatile(
	"{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
	: "=&r" (retval)
	: "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
	: "p0"
	);

	return retval;
	}

	static __always_inline bool
	arch_test_bit_acquire(unsigned long nr, const volatile unsigned long *addr)
	{
	int retval;

	asm volatile(
	"{P0 = tstbit(%1,%2); if (P0.new) %0 = #1; if (!P0.new) %0 = #0;}\n"
	: "=&r" (retval)
	: "r" (addr[BIT_WORD(nr)]), "r" (nr % BITS_PER_LONG)
	: "p0", "memory"
	);

	return retval;
	}

	/*
	* ffz - find first zero in word.
	* @word: The word to search
	*
	* Undefined if no zero exists, so code should check against ~0UL first.
	*/
	static inline long ffz(int x)
	{
	int r;

	asm("%0 = ct1(%1);\n"
	: "=&r" (r)
	: "r" (x));
	return r;
	}

	/*
	* fls - find last (most-significant) bit set
	* @x: 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(unsigned int x)
	{
	int r;

	asm("{ %0 = cl0(%1);}\n"
	"%0 = sub(#32,%0);\n"
	: "=&r" (r)
	: "r" (x)
	: "p0");

	return r;
	}

	/*
	* ffs - find first bit set
	* @x: 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 x)
	{
	int r;

	asm("{ P0 = cmp.eq(%1,#0); %0 = ct0(%1);}\n"
	"{ if (P0) %0 = #0; if (!P0) %0 = add(%0,#1);}\n"
	: "=&r" (r)
	: "r" (x)
	: "p0");

	return r;
	}

	/*
	* __ffs - find first bit in word.
	* @word: The word to search
	*
	* Undefined if no bit exists, so code should check against 0 first.
	*
	* bits_per_long assumed to be 32
	* numbering starts at 0 I think (instead of 1 like ffs)
	*/
	static inline unsigned long __ffs(unsigned long word)
	{
	int num;

	asm("%0 = ct0(%1);\n"
	: "=&r" (num)
	: "r" (word));

	return num;
	}

	/*
	* __fls - find last (most-significant) set bit in a long word
	* @word: the word to search
	*
	* Undefined if no set bit exists, so code should check against 0 first.
	* bits_per_long assumed to be 32
	*/
	static inline unsigned long __fls(unsigned long word)
	{
	int num;

	asm("%0 = cl0(%1);\n"
	"%0 = sub(#31,%0);\n"
	: "=&r" (num)
	: "r" (word));

	return num;
	}

	#include <asm-generic/bitops/lock.h>
	#include <asm-generic/bitops/non-instrumented-non-atomic.h>

	#include <asm-generic/bitops/fls64.h>
	#include <asm-generic/bitops/sched.h>
	#include <asm-generic/bitops/hweight.h>

	#include <asm-generic/bitops/le.h>
	#include <asm-generic/bitops/ext2-atomic.h>

	#endif /* __KERNEL__ */
	#endif