diff options
Diffstat (limited to 'arch/riscv/include/asm/bitops.h')
| -rw-r--r-- | arch/riscv/include/asm/bitops.h | 224 |
1 files changed, 199 insertions, 25 deletions
diff --git a/arch/riscv/include/asm/bitops.h b/arch/riscv/include/asm/bitops.h index 396a3303c537..d59310f74c2b 100644 --- a/arch/riscv/include/asm/bitops.h +++ b/arch/riscv/include/asm/bitops.h @@ -15,16 +15,175 @@ #include <asm/barrier.h> #include <asm/bitsperlong.h> +#if !(defined(CONFIG_RISCV_ISA_ZBB) && defined(CONFIG_TOOLCHAIN_HAS_ZBB)) || defined(NO_ALTERNATIVE) #include <asm-generic/bitops/__ffs.h> -#include <asm-generic/bitops/ffz.h> +#include <asm-generic/bitops/__fls.h> +#include <asm-generic/bitops/ffs.h> #include <asm-generic/bitops/fls.h> + +#else +#define __HAVE_ARCH___FFS +#define __HAVE_ARCH___FLS +#define __HAVE_ARCH_FFS +#define __HAVE_ARCH_FLS + +#include <asm-generic/bitops/__ffs.h> #include <asm-generic/bitops/__fls.h> +#include <asm-generic/bitops/ffs.h> +#include <asm-generic/bitops/fls.h> + +#include <asm/alternative-macros.h> +#include <asm/hwcap.h> + +#if (BITS_PER_LONG == 64) +#define CTZW "ctzw " +#define CLZW "clzw " +#elif (BITS_PER_LONG == 32) +#define CTZW "ctz " +#define CLZW "clz " +#else +#error "Unexpected BITS_PER_LONG" +#endif + +static __always_inline unsigned long variable__ffs(unsigned long word) +{ + asm goto(ALTERNATIVE("j %l[legacy]", "nop", 0, + RISCV_ISA_EXT_ZBB, 1) + : : : : legacy); + + asm volatile (".option push\n" + ".option arch,+zbb\n" + "ctz %0, %1\n" + ".option pop\n" + : "=r" (word) : "r" (word) :); + + return word; + +legacy: + return generic___ffs(word); +} + +/** + * __ffs - find first set bit in a long word + * @word: The word to search + * + * Undefined if no set bit exists, so code should check against 0 first. + */ +#define __ffs(word) \ + (__builtin_constant_p(word) ? \ + (unsigned long)__builtin_ctzl(word) : \ + variable__ffs(word)) + +static __always_inline unsigned long variable__fls(unsigned long word) +{ + asm goto(ALTERNATIVE("j %l[legacy]", "nop", 0, + RISCV_ISA_EXT_ZBB, 1) + : : : : legacy); + + asm volatile (".option push\n" + ".option arch,+zbb\n" + "clz %0, %1\n" + ".option pop\n" + : "=r" (word) : "r" (word) :); + + return BITS_PER_LONG - 1 - word; + +legacy: + return generic___fls(word); +} + +/** + * __fls - find last set bit in a long word + * @word: the word to search + * + * Undefined if no set bit exists, so code should check against 0 first. + */ +#define __fls(word) \ + (__builtin_constant_p(word) ? \ + (unsigned long)(BITS_PER_LONG - 1 - __builtin_clzl(word)) : \ + variable__fls(word)) + +static __always_inline int variable_ffs(int x) +{ + asm goto(ALTERNATIVE("j %l[legacy]", "nop", 0, + RISCV_ISA_EXT_ZBB, 1) + : : : : legacy); + + if (!x) + return 0; + + asm volatile (".option push\n" + ".option arch,+zbb\n" + CTZW "%0, %1\n" + ".option pop\n" + : "=r" (x) : "r" (x) :); + + return x + 1; + +legacy: + return generic_ffs(x); +} + +/** + * ffs - find first set bit in a word + * @x: the word to search + * + * This is defined the same way as the libc and compiler builtin ffs routines. + * + * ffs(value) returns 0 if value is 0 or the position of the first set bit if + * value is nonzero. The first (least significant) bit is at position 1. + */ +#define ffs(x) (__builtin_constant_p(x) ? __builtin_ffs(x) : variable_ffs(x)) + +static __always_inline int variable_fls(unsigned int x) +{ + asm goto(ALTERNATIVE("j %l[legacy]", "nop", 0, + RISCV_ISA_EXT_ZBB, 1) + : : : : legacy); + + if (!x) + return 0; + + asm volatile (".option push\n" + ".option arch,+zbb\n" + CLZW "%0, %1\n" + ".option pop\n" + : "=r" (x) : "r" (x) :); + + return 32 - x; + +legacy: + return generic_fls(x); +} + +/** + * fls - find last set bit in a word + * @x: the word to search + * + * This is defined in a similar way as ffs, but returns the position of the most + * significant set bit. + * + * fls(value) returns 0 if value is 0 or the position of the last set bit if + * value is nonzero. The last (most significant) bit is at position 32. + */ +#define fls(x) \ +({ \ + typeof(x) x_ = (x); \ + __builtin_constant_p(x_) ? \ + ((x_ != 0) ? (32 - __builtin_clz(x_)) : 0) \ + : \ + variable_fls(x_); \ +}) + +#endif /* !(defined(CONFIG_RISCV_ISA_ZBB) && defined(CONFIG_TOOLCHAIN_HAS_ZBB)) || defined(NO_ALTERNATIVE) */ + +#include <asm-generic/bitops/ffz.h> #include <asm-generic/bitops/fls64.h> -#include <asm-generic/bitops/find.h> #include <asm-generic/bitops/sched.h> -#include <asm-generic/bitops/ffs.h> -#include <asm-generic/bitops/hweight.h> +#include <asm/arch_hweight.h> + +#include <asm-generic/bitops/const_hweight.h> #if (BITS_PER_LONG == 64) #define __AMO(op) "amo" #op ".d" @@ -63,44 +222,44 @@ #define __NOT(x) (~(x)) /** - * test_and_set_bit - Set a bit and return its old value + * arch_test_and_set_bit - Set a bit and return its old value * @nr: Bit to set * @addr: Address to count from * - * This operation may be reordered on other architectures than x86. + * This is an atomic fully-ordered operation (implied full memory barrier). */ -static inline int test_and_set_bit(int nr, volatile unsigned long *addr) +static __always_inline int arch_test_and_set_bit(int nr, volatile unsigned long *addr) { return __test_and_op_bit(or, __NOP, nr, addr); } /** - * test_and_clear_bit - Clear a bit and return its old value + * arch_test_and_clear_bit - Clear a bit and return its old value * @nr: Bit to clear * @addr: Address to count from * - * This operation can be reordered on other architectures other than x86. + * This is an atomic fully-ordered operation (implied full memory barrier). */ -static inline int test_and_clear_bit(int nr, volatile unsigned long *addr) +static __always_inline int arch_test_and_clear_bit(int nr, volatile unsigned long *addr) { return __test_and_op_bit(and, __NOT, nr, addr); } /** - * test_and_change_bit - Change a bit and return its old value + * arch_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(int nr, volatile unsigned long *addr) +static __always_inline int arch_test_and_change_bit(int nr, volatile unsigned long *addr) { return __test_and_op_bit(xor, __NOP, nr, addr); } /** - * set_bit - Atomically set a bit in memory + * arch_set_bit - Atomically set a bit in memory * @nr: the bit to set * @addr: the address to start counting from * @@ -111,13 +270,13 @@ static inline int test_and_change_bit(int nr, volatile unsigned long *addr) * 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(int nr, volatile unsigned long *addr) +static __always_inline void arch_set_bit(int nr, volatile unsigned long *addr) { __op_bit(or, __NOP, nr, addr); } /** - * clear_bit - Clears a bit in memory + * arch_clear_bit - Clears a bit in memory * @nr: Bit to clear * @addr: Address to start counting from * @@ -125,13 +284,13 @@ static inline void set_bit(int nr, volatile unsigned long *addr) * on non x86 architectures, so if you are writing portable code, * make sure not to rely on its reordering guarantees. */ -static inline void clear_bit(int nr, volatile unsigned long *addr) +static __always_inline void arch_clear_bit(int nr, volatile unsigned long *addr) { __op_bit(and, __NOT, nr, addr); } /** - * change_bit - Toggle a bit in memory + * arch_change_bit - Toggle a bit in memory * @nr: Bit to change * @addr: Address to start counting from * @@ -139,40 +298,40 @@ static inline void clear_bit(int nr, volatile unsigned long *addr) * 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(int nr, volatile unsigned long *addr) +static __always_inline void arch_change_bit(int nr, volatile unsigned long *addr) { __op_bit(xor, __NOP, nr, addr); } /** - * test_and_set_bit_lock - Set a bit and return its old value, for lock + * arch_test_and_set_bit_lock - Set a bit and return its old value, for lock * @nr: Bit to set * @addr: Address to count from * * This operation is atomic and provides acquire barrier semantics. * It can be used to implement bit locks. */ -static inline int test_and_set_bit_lock( +static __always_inline int arch_test_and_set_bit_lock( unsigned long nr, volatile unsigned long *addr) { return __test_and_op_bit_ord(or, __NOP, nr, addr, .aq); } /** - * clear_bit_unlock - Clear a bit in memory, for unlock + * arch_clear_bit_unlock - Clear a bit in memory, for unlock * @nr: the bit to set * @addr: the address to start counting from * * This operation is atomic and provides release barrier semantics. */ -static inline void clear_bit_unlock( +static __always_inline void arch_clear_bit_unlock( unsigned long nr, volatile unsigned long *addr) { __op_bit_ord(and, __NOT, nr, addr, .rl); } /** - * __clear_bit_unlock - Clear a bit in memory, for unlock + * arch___clear_bit_unlock - Clear a bit in memory, for unlock * @nr: the bit to set * @addr: the address to start counting from * @@ -186,10 +345,22 @@ static inline void clear_bit_unlock( * non-atomic property here: it's a lot more instructions and we still have to * provide release semantics anyway. */ -static inline void __clear_bit_unlock( +static __always_inline void arch___clear_bit_unlock( unsigned long nr, volatile unsigned long *addr) { - clear_bit_unlock(nr, addr); + arch_clear_bit_unlock(nr, addr); +} + +static __always_inline bool arch_xor_unlock_is_negative_byte(unsigned long mask, + volatile unsigned long *addr) +{ + unsigned long res; + __asm__ __volatile__ ( + __AMO(xor) ".rl %0, %2, %1" + : "=r" (res), "+A" (*addr) + : "r" (__NOP(mask)) + : "memory"); + return (res & BIT(7)) != 0; } #undef __test_and_op_bit @@ -198,6 +369,9 @@ static inline void __clear_bit_unlock( #undef __NOT #undef __AMO +#include <asm-generic/bitops/instrumented-atomic.h> +#include <asm-generic/bitops/instrumented-lock.h> + #include <asm-generic/bitops/non-atomic.h> #include <asm-generic/bitops/le.h> #include <asm-generic/bitops/ext2-atomic.h> |