diff options
author | Guo Ren <ren_guo@c-sky.com> | 2018-09-05 14:25:16 +0800 |
---|---|---|
committer | Guo Ren <ren_guo@c-sky.com> | 2018-10-26 00:54:23 +0800 |
commit | a0ae62806ff495b60235cc4f2fee3f3ab6a265c9 (patch) | |
tree | 6b48093798b6fefb1fd179db71c106b19457df2a /arch/csky | |
parent | e38a5272baaa81b31680389efdec0c9008e17446 (diff) |
csky: Atomic operations
This patch adds atomic, cmpxchg, spinlock files.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Peter Zijlstra <peterz@infradead.org>
Diffstat (limited to 'arch/csky')
-rw-r--r-- | arch/csky/include/asm/atomic.h | 212 | ||||
-rw-r--r-- | arch/csky/include/asm/cmpxchg.h | 73 | ||||
-rw-r--r-- | arch/csky/include/asm/spinlock.h | 256 | ||||
-rw-r--r-- | arch/csky/include/asm/spinlock_types.h | 37 | ||||
-rw-r--r-- | arch/csky/kernel/atomic.S | 87 |
5 files changed, 665 insertions, 0 deletions
diff --git a/arch/csky/include/asm/atomic.h b/arch/csky/include/asm/atomic.h new file mode 100644 index 000000000000..e369d73b13e3 --- /dev/null +++ b/arch/csky/include/asm/atomic.h @@ -0,0 +1,212 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_CSKY_ATOMIC_H +#define __ASM_CSKY_ATOMIC_H + +#include <linux/version.h> +#include <asm/cmpxchg.h> +#include <asm/barrier.h> + +#ifdef CONFIG_CPU_HAS_LDSTEX + +#define __atomic_add_unless __atomic_add_unless +static inline int __atomic_add_unless(atomic_t *v, int a, int u) +{ + unsigned long tmp, ret; + + smp_mb(); + + asm volatile ( + "1: ldex.w %0, (%3) \n" + " mov %1, %0 \n" + " cmpne %0, %4 \n" + " bf 2f \n" + " add %0, %2 \n" + " stex.w %0, (%3) \n" + " bez %0, 1b \n" + "2: \n" + : "=&r" (tmp), "=&r" (ret) + : "r" (a), "r"(&v->counter), "r"(u) + : "memory"); + + if (ret != u) + smp_mb(); + + return ret; +} + +#define ATOMIC_OP(op, c_op) \ +static inline void atomic_##op(int i, atomic_t *v) \ +{ \ + unsigned long tmp; \ + \ + asm volatile ( \ + "1: ldex.w %0, (%2) \n" \ + " " #op " %0, %1 \n" \ + " stex.w %0, (%2) \n" \ + " bez %0, 1b \n" \ + : "=&r" (tmp) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ +} + +#define ATOMIC_OP_RETURN(op, c_op) \ +static inline int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + unsigned long tmp, ret; \ + \ + smp_mb(); \ + asm volatile ( \ + "1: ldex.w %0, (%3) \n" \ + " " #op " %0, %2 \n" \ + " mov %1, %0 \n" \ + " stex.w %0, (%3) \n" \ + " bez %0, 1b \n" \ + : "=&r" (tmp), "=&r" (ret) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ + smp_mb(); \ + \ + return ret; \ +} + +#define ATOMIC_FETCH_OP(op, c_op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + unsigned long tmp, ret; \ + \ + smp_mb(); \ + asm volatile ( \ + "1: ldex.w %0, (%3) \n" \ + " mov %1, %0 \n" \ + " " #op " %0, %2 \n" \ + " stex.w %0, (%3) \n" \ + " bez %0, 1b \n" \ + : "=&r" (tmp), "=&r" (ret) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ + smp_mb(); \ + \ + return ret; \ +} + +#else /* CONFIG_CPU_HAS_LDSTEX */ + +#include <linux/irqflags.h> + +#define __atomic_add_unless __atomic_add_unless +static inline int __atomic_add_unless(atomic_t *v, int a, int u) +{ + unsigned long tmp, ret, flags; + + raw_local_irq_save(flags); + + asm volatile ( + " ldw %0, (%3) \n" + " mov %1, %0 \n" + " cmpne %0, %4 \n" + " bf 2f \n" + " add %0, %2 \n" + " stw %0, (%3) \n" + "2: \n" + : "=&r" (tmp), "=&r" (ret) + : "r" (a), "r"(&v->counter), "r"(u) + : "memory"); + + raw_local_irq_restore(flags); + + return ret; +} + +#define ATOMIC_OP(op, c_op) \ +static inline void atomic_##op(int i, atomic_t *v) \ +{ \ + unsigned long tmp, flags; \ + \ + raw_local_irq_save(flags); \ + \ + asm volatile ( \ + " ldw %0, (%2) \n" \ + " " #op " %0, %1 \n" \ + " stw %0, (%2) \n" \ + : "=&r" (tmp) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ + \ + raw_local_irq_restore(flags); \ +} + +#define ATOMIC_OP_RETURN(op, c_op) \ +static inline int atomic_##op##_return(int i, atomic_t *v) \ +{ \ + unsigned long tmp, ret, flags; \ + \ + raw_local_irq_save(flags); \ + \ + asm volatile ( \ + " ldw %0, (%3) \n" \ + " " #op " %0, %2 \n" \ + " stw %0, (%3) \n" \ + " mov %1, %0 \n" \ + : "=&r" (tmp), "=&r" (ret) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ + \ + raw_local_irq_restore(flags); \ + \ + return ret; \ +} + +#define ATOMIC_FETCH_OP(op, c_op) \ +static inline int atomic_fetch_##op(int i, atomic_t *v) \ +{ \ + unsigned long tmp, ret, flags; \ + \ + raw_local_irq_save(flags); \ + \ + asm volatile ( \ + " ldw %0, (%3) \n" \ + " mov %1, %0 \n" \ + " " #op " %0, %2 \n" \ + " stw %0, (%3) \n" \ + : "=&r" (tmp), "=&r" (ret) \ + : "r" (i), "r"(&v->counter) \ + : "memory"); \ + \ + raw_local_irq_restore(flags); \ + \ + return ret; \ +} + +#endif /* CONFIG_CPU_HAS_LDSTEX */ + +#define atomic_add_return atomic_add_return +ATOMIC_OP_RETURN(add, +) +#define atomic_sub_return atomic_sub_return +ATOMIC_OP_RETURN(sub, -) + +#define atomic_fetch_add atomic_fetch_add +ATOMIC_FETCH_OP(add, +) +#define atomic_fetch_sub atomic_fetch_sub +ATOMIC_FETCH_OP(sub, -) +#define atomic_fetch_and atomic_fetch_and +ATOMIC_FETCH_OP(and, &) +#define atomic_fetch_or atomic_fetch_or +ATOMIC_FETCH_OP(or, |) +#define atomic_fetch_xor atomic_fetch_xor +ATOMIC_FETCH_OP(xor, ^) + +#define atomic_and atomic_and +ATOMIC_OP(and, &) +#define atomic_or atomic_or +ATOMIC_OP(or, |) +#define atomic_xor atomic_xor +ATOMIC_OP(xor, ^) + +#undef ATOMIC_FETCH_OP +#undef ATOMIC_OP_RETURN +#undef ATOMIC_OP + +#include <asm-generic/atomic.h> + +#endif /* __ASM_CSKY_ATOMIC_H */ diff --git a/arch/csky/include/asm/cmpxchg.h b/arch/csky/include/asm/cmpxchg.h new file mode 100644 index 000000000000..89224530a0ee --- /dev/null +++ b/arch/csky/include/asm/cmpxchg.h @@ -0,0 +1,73 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_CSKY_CMPXCHG_H +#define __ASM_CSKY_CMPXCHG_H + +#ifdef CONFIG_CPU_HAS_LDSTEX +#include <asm/barrier.h> + +extern void __bad_xchg(void); + +#define __xchg(new, ptr, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(*(ptr)) __ret; \ + unsigned long tmp; \ + switch (size) { \ + case 4: \ + smp_mb(); \ + asm volatile ( \ + "1: ldex.w %0, (%3) \n" \ + " mov %1, %2 \n" \ + " stex.w %1, (%3) \n" \ + " bez %1, 1b \n" \ + : "=&r" (__ret), "=&r" (tmp) \ + : "r" (__new), "r"(__ptr) \ + :); \ + smp_mb(); \ + break; \ + default: \ + __bad_xchg(); \ + } \ + __ret; \ +}) + +#define xchg(ptr, x) (__xchg((x), (ptr), sizeof(*(ptr)))) + +#define __cmpxchg(ptr, old, new, size) \ +({ \ + __typeof__(ptr) __ptr = (ptr); \ + __typeof__(new) __new = (new); \ + __typeof__(new) __tmp; \ + __typeof__(old) __old = (old); \ + __typeof__(*(ptr)) __ret; \ + switch (size) { \ + case 4: \ + smp_mb(); \ + asm volatile ( \ + "1: ldex.w %0, (%3) \n" \ + " cmpne %0, %4 \n" \ + " bt 2f \n" \ + " mov %1, %2 \n" \ + " stex.w %1, (%3) \n" \ + " bez %1, 1b \n" \ + "2: \n" \ + : "=&r" (__ret), "=&r" (__tmp) \ + : "r" (__new), "r"(__ptr), "r"(__old) \ + :); \ + smp_mb(); \ + break; \ + default: \ + __bad_xchg(); \ + } \ + __ret; \ +}) + +#define cmpxchg(ptr, o, n) \ + (__cmpxchg((ptr), (o), (n), sizeof(*(ptr)))) +#else +#include <asm-generic/cmpxchg.h> +#endif + +#endif /* __ASM_CSKY_CMPXCHG_H */ diff --git a/arch/csky/include/asm/spinlock.h b/arch/csky/include/asm/spinlock.h new file mode 100644 index 000000000000..7cf3f2b34cea --- /dev/null +++ b/arch/csky/include/asm/spinlock.h @@ -0,0 +1,256 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_CSKY_SPINLOCK_H +#define __ASM_CSKY_SPINLOCK_H + +#include <linux/spinlock_types.h> +#include <asm/barrier.h> + +#ifdef CONFIG_QUEUED_RWLOCKS + +/* + * Ticket-based spin-locking. + */ +static inline void arch_spin_lock(arch_spinlock_t *lock) +{ + arch_spinlock_t lockval; + u32 ticket_next = 1 << TICKET_NEXT; + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%2) \n" + " mov %1, %0 \n" + " add %0, %3 \n" + " stex.w %0, (%2) \n" + " bez %0, 1b \n" + : "=&r" (tmp), "=&r" (lockval) + : "r"(p), "r"(ticket_next) + : "cc"); + + while (lockval.tickets.next != lockval.tickets.owner) + lockval.tickets.owner = READ_ONCE(lock->tickets.owner); + + smp_mb(); +} + +static inline int arch_spin_trylock(arch_spinlock_t *lock) +{ + u32 tmp, contended, res; + u32 ticket_next = 1 << TICKET_NEXT; + u32 *p = &lock->lock; + + do { + asm volatile ( + " ldex.w %0, (%3) \n" + " movi %2, 1 \n" + " rotli %1, %0, 16 \n" + " cmpne %1, %0 \n" + " bt 1f \n" + " movi %2, 0 \n" + " add %0, %0, %4 \n" + " stex.w %0, (%3) \n" + "1: \n" + : "=&r" (res), "=&r" (tmp), "=&r" (contended) + : "r"(p), "r"(ticket_next) + : "cc"); + } while (!res); + + if (!contended) + smp_mb(); + + return !contended; +} + +static inline void arch_spin_unlock(arch_spinlock_t *lock) +{ + smp_mb(); + WRITE_ONCE(lock->tickets.owner, lock->tickets.owner + 1); +} + +static inline int arch_spin_value_unlocked(arch_spinlock_t lock) +{ + return lock.tickets.owner == lock.tickets.next; +} + +static inline int arch_spin_is_locked(arch_spinlock_t *lock) +{ + return !arch_spin_value_unlocked(READ_ONCE(*lock)); +} + +static inline int arch_spin_is_contended(arch_spinlock_t *lock) +{ + struct __raw_tickets tickets = READ_ONCE(lock->tickets); + + return (tickets.next - tickets.owner) > 1; +} +#define arch_spin_is_contended arch_spin_is_contended + +#include <asm/qrwlock.h> + +/* See include/linux/spinlock.h */ +#define smp_mb__after_spinlock() smp_mb() + +#else /* CONFIG_QUEUED_RWLOCKS */ + +/* + * Test-and-set spin-locking. + */ +static inline void arch_spin_lock(arch_spinlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " bnez %0, 1b \n" + " movi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + smp_mb(); +} + +static inline void arch_spin_unlock(arch_spinlock_t *lock) +{ + smp_mb(); + WRITE_ONCE(lock->lock, 0); +} + +static inline int arch_spin_trylock(arch_spinlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " bnez %0, 2f \n" + " movi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + " movi %0, 0 \n" + "2: \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + + if (!tmp) + smp_mb(); + + return !tmp; +} + +#define arch_spin_is_locked(x) (READ_ONCE((x)->lock) != 0) + +/* + * read lock/unlock/trylock + */ +static inline void arch_read_lock(arch_rwlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " blz %0, 1b \n" + " addi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + smp_mb(); +} + +static inline void arch_read_unlock(arch_rwlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + smp_mb(); + asm volatile ( + "1: ldex.w %0, (%1) \n" + " subi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); +} + +static inline int arch_read_trylock(arch_rwlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " blz %0, 2f \n" + " addi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + " movi %0, 0 \n" + "2: \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + + if (!tmp) + smp_mb(); + + return !tmp; +} + +/* + * write lock/unlock/trylock + */ +static inline void arch_write_lock(arch_rwlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " bnez %0, 1b \n" + " subi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + smp_mb(); +} + +static inline void arch_write_unlock(arch_rwlock_t *lock) +{ + smp_mb(); + WRITE_ONCE(lock->lock, 0); +} + +static inline int arch_write_trylock(arch_rwlock_t *lock) +{ + u32 *p = &lock->lock; + u32 tmp; + + asm volatile ( + "1: ldex.w %0, (%1) \n" + " bnez %0, 2f \n" + " subi %0, 1 \n" + " stex.w %0, (%1) \n" + " bez %0, 1b \n" + " movi %0, 0 \n" + "2: \n" + : "=&r" (tmp) + : "r"(p) + : "cc"); + + if (!tmp) + smp_mb(); + + return !tmp; +} + +#endif /* CONFIG_QUEUED_RWLOCKS */ +#endif /* __ASM_CSKY_SPINLOCK_H */ diff --git a/arch/csky/include/asm/spinlock_types.h b/arch/csky/include/asm/spinlock_types.h new file mode 100644 index 000000000000..88b82438b182 --- /dev/null +++ b/arch/csky/include/asm/spinlock_types.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef __ASM_CSKY_SPINLOCK_TYPES_H +#define __ASM_CSKY_SPINLOCK_TYPES_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +# error "please don't include this file directly" +#endif + +#define TICKET_NEXT 16 + +typedef struct { + union { + u32 lock; + struct __raw_tickets { + /* little endian */ + u16 owner; + u16 next; + } tickets; + }; +} arch_spinlock_t; + +#define __ARCH_SPIN_LOCK_UNLOCKED { { 0 } } + +#ifdef CONFIG_QUEUED_RWLOCKS +#include <asm-generic/qrwlock_types.h> + +#else /* CONFIG_NR_CPUS > 2 */ + +typedef struct { + u32 lock; +} arch_rwlock_t; + +#define __ARCH_RW_LOCK_UNLOCKED { 0 } + +#endif /* CONFIG_QUEUED_RWLOCKS */ +#endif /* __ASM_CSKY_SPINLOCK_TYPES_H */ diff --git a/arch/csky/kernel/atomic.S b/arch/csky/kernel/atomic.S new file mode 100644 index 000000000000..d2357c8f85bd --- /dev/null +++ b/arch/csky/kernel/atomic.S @@ -0,0 +1,87 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. + +#include <linux/linkage.h> +#include <abi/entry.h> + +.text + +/* + * int csky_cmpxchg(int oldval, int newval, int *ptr) + * + * If *ptr != oldval && return 1, + * else *ptr = newval return 0. + */ +#ifdef CONFIG_CPU_HAS_LDSTEX +ENTRY(csky_cmpxchg) + USPTOKSP + mfcr a3, epc + INCTRAP a3 + + subi sp, 8 + stw a3, (sp, 0) + mfcr a3, epsr + stw a3, (sp, 4) + + psrset ee +1: + ldex a3, (a2) + cmpne a0, a3 + bt16 2f + mov a3, a1 + stex a3, (a2) + bez a3, 1b +2: + sync.is + mvc a0 + ldw a3, (sp, 0) + mtcr a3, epc + ldw a3, (sp, 4) + mtcr a3, epsr + addi sp, 8 + KSPTOUSP + rte +END(csky_cmpxchg) +#else +ENTRY(csky_cmpxchg) + USPTOKSP + mfcr a3, epc + INCTRAP a3 + + subi sp, 8 + stw a3, (sp, 0) + mfcr a3, epsr + stw a3, (sp, 4) + + psrset ee +1: + ldw a3, (a2) + cmpne a0, a3 + bt16 3f +2: + stw a1, (a2) +3: + mvc a0 + ldw a3, (sp, 0) + mtcr a3, epc + ldw a3, (sp, 4) + mtcr a3, epsr + addi sp, 8 + KSPTOUSP + rte +END(csky_cmpxchg) + +/* + * Called from tlbmodified exception + */ +ENTRY(csky_cmpxchg_fixup) + mfcr a0, epc + lrw a1, 2b + cmpne a1, a0 + bt 1f + subi a1, (2b - 1b) + stw a1, (sp, LSAVE_PC) +1: + rts +END(csky_cmpxchg_fixup) +#endif |