diff options
author | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-13 09:49:04 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-10-13 09:49:04 -0700 |
commit | dcf397f037f52add9945eced57ca300ab6a4413c (patch) | |
tree | e78767d164589e9097a54bf564b072fb01f80820 /include/asm-sh/spinlock.h | |
parent | 6faf035cf9fdd8283c2b2b2c34b76b5445ec6fc4 (diff) | |
parent | 68ee0f9c98a42e36f9eab29155b2bb0e7e409ac6 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (124 commits)
sh: allow building for both r2d boards in same binary.
sh: fix r2d board detection
sh: Discard .exit.text/.exit.data at runtime.
sh: Fix up some section alignments in linker script.
sh: Fix SH-4 DMAC CHCR masking.
sh: Rip out left-over nommu cond syscall cruft.
sh: Make kgdb i-cache flushing less inept.
sh: kgdb section mismatches and tidying.
sh: cleanup struct irqaction initializers.
sh: early_printk tidying.
video: pvr2fb: Add TV (RGB) support to Dreamcast PVR driver.
sh: Conditionalize gUSA support.
sh: Follow gUSA preempt changes in __switch_to().
sh: Tidy up gUSA preempt handling.
sh: __copy_user() optimizations for small copies.
sh: clkfwk: Support multi-level clock propagation.
sh: Fix URAM start address on SH7785.
sh: Use boot_cpu_data for CPU probe.
sh: Support extended mode TLB on SH-X3.
sh: Bump MAX_ACTIVE_REGIONS for SH7785.
...
Diffstat (limited to 'include/asm-sh/spinlock.h')
-rw-r--r-- | include/asm-sh/spinlock.h | 181 |
1 files changed, 142 insertions, 39 deletions
diff --git a/include/asm-sh/spinlock.h b/include/asm-sh/spinlock.h index 92f6e2008b2..e793181d64d 100644 --- a/include/asm-sh/spinlock.h +++ b/include/asm-sh/spinlock.h @@ -2,6 +2,7 @@ * include/asm-sh/spinlock.h * * Copyright (C) 2002, 2003 Paul Mundt + * Copyright (C) 2006, 2007 Akio Idehara * * 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 @@ -10,17 +11,22 @@ #ifndef __ASM_SH_SPINLOCK_H #define __ASM_SH_SPINLOCK_H -#include <asm/atomic.h> -#include <asm/spinlock_types.h> +/* + * The only locking implemented here uses SH-4A opcodes. For others, + * split this out as per atomic-*.h. + */ +#ifndef CONFIG_CPU_SH4A +#error "Need movli.l/movco.l for spinlocks" +#endif /* * Your basic SMP spinlocks, allowing only a single CPU anywhere */ -#define __raw_spin_is_locked(x) ((x)->lock != 0) +#define __raw_spin_is_locked(x) ((x)->lock <= 0) #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) #define __raw_spin_unlock_wait(x) \ - do { cpu_relax(); } while (__raw_spin_is_locked(x)) + do { cpu_relax(); } while ((x)->lock) /* * Simple spin lock operations. There are two variants, one clears IRQ's @@ -30,12 +36,19 @@ */ static inline void __raw_spin_lock(raw_spinlock_t *lock) { + unsigned long tmp; + unsigned long oldval; + __asm__ __volatile__ ( - "1:\n\t" - "tas.b @%0\n\t" - "bf/s 1b\n\t" - "nop\n\t" - : "=r" (lock->lock) + "1: \n\t" + "movli.l @%2, %0 ! __raw_spin_lock \n\t" + "mov %0, %1 \n\t" + "mov #0, %0 \n\t" + "movco.l %0, @%2 \n\t" + "bf 1b \n\t" + "cmp/pl %1 \n\t" + "bf 1b \n\t" + : "=&z" (tmp), "=&r" (oldval) : "r" (&lock->lock) : "t", "memory" ); @@ -43,12 +56,36 @@ static inline void __raw_spin_lock(raw_spinlock_t *lock) static inline void __raw_spin_unlock(raw_spinlock_t *lock) { - //assert_spin_locked(lock); + unsigned long tmp; - lock->lock = 0; + __asm__ __volatile__ ( + "mov #1, %0 ! __raw_spin_unlock \n\t" + "mov.l %0, @%1 \n\t" + : "=&z" (tmp) + : "r" (&lock->lock) + : "t", "memory" + ); } -#define __raw_spin_trylock(x) (!test_and_set_bit(0, &(x)->lock)) +static inline int __raw_spin_trylock(raw_spinlock_t *lock) +{ + unsigned long tmp, oldval; + + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%2, %0 ! __raw_spin_trylock \n\t" + "mov %0, %1 \n\t" + "mov #0, %0 \n\t" + "movco.l %0, @%2 \n\t" + "bf 1b \n\t" + "synco \n\t" + : "=&z" (tmp), "=&r" (oldval) + : "r" (&lock->lock) + : "t", "memory" + ); + + return oldval; +} /* * Read-write spinlocks, allowing multiple readers but only one writer. @@ -59,58 +96,124 @@ static inline void __raw_spin_unlock(raw_spinlock_t *lock) * read-locks. */ +/** + * read_can_lock - would read_trylock() succeed? + * @lock: the rwlock in question. + */ +#define __raw_read_can_lock(x) ((x)->lock > 0) + +/** + * write_can_lock - would write_trylock() succeed? + * @lock: the rwlock in question. + */ +#define __raw_write_can_lock(x) ((x)->lock == RW_LOCK_BIAS) + static inline void __raw_read_lock(raw_rwlock_t *rw) { - __raw_spin_lock(&rw->lock); - - atomic_inc(&rw->counter); + unsigned long tmp; - __raw_spin_unlock(&rw->lock); + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%1, %0 ! __raw_read_lock \n\t" + "cmp/pl %0 \n\t" + "bf 1b \n\t" + "add #-1, %0 \n\t" + "movco.l %0, @%1 \n\t" + "bf 1b \n\t" + : "=&z" (tmp) + : "r" (&rw->lock) + : "t", "memory" + ); } static inline void __raw_read_unlock(raw_rwlock_t *rw) { - __raw_spin_lock(&rw->lock); - - atomic_dec(&rw->counter); + unsigned long tmp; - __raw_spin_unlock(&rw->lock); + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%1, %0 ! __raw_read_unlock \n\t" + "add #1, %0 \n\t" + "movco.l %0, @%1 \n\t" + "bf 1b \n\t" + : "=&z" (tmp) + : "r" (&rw->lock) + : "t", "memory" + ); } static inline void __raw_write_lock(raw_rwlock_t *rw) { - __raw_spin_lock(&rw->lock); - atomic_set(&rw->counter, -1); + unsigned long tmp; + + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%1, %0 ! __raw_write_lock \n\t" + "cmp/hs %2, %0 \n\t" + "bf 1b \n\t" + "sub %2, %0 \n\t" + "movco.l %0, @%1 \n\t" + "bf 1b \n\t" + : "=&z" (tmp) + : "r" (&rw->lock), "r" (RW_LOCK_BIAS) + : "t", "memory" + ); } static inline void __raw_write_unlock(raw_rwlock_t *rw) { - atomic_set(&rw->counter, 0); - __raw_spin_unlock(&rw->lock); + __asm__ __volatile__ ( + "mov.l %1, @%0 ! __raw_write_unlock \n\t" + : + : "r" (&rw->lock), "r" (RW_LOCK_BIAS) + : "t", "memory" + ); } -static inline int __raw_write_can_lock(raw_rwlock_t *rw) +static inline int __raw_read_trylock(raw_rwlock_t *rw) { - return (atomic_read(&rw->counter) == RW_LOCK_BIAS); -} + unsigned long tmp, oldval; -static inline int __raw_read_trylock(raw_rwlock_t *lock) -{ - atomic_t *count = (atomic_t*)lock; - if (atomic_dec_return(count) >= 0) - return 1; - atomic_inc(count); - return 0; + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%2, %0 ! __raw_read_trylock \n\t" + "mov %0, %1 \n\t" + "cmp/pl %0 \n\t" + "bf 2f \n\t" + "add #-1, %0 \n\t" + "movco.l %0, @%2 \n\t" + "bf 1b \n\t" + "2: \n\t" + "synco \n\t" + : "=&z" (tmp), "=&r" (oldval) + : "r" (&rw->lock) + : "t", "memory" + ); + + return (oldval > 0); } static inline int __raw_write_trylock(raw_rwlock_t *rw) { - if (atomic_sub_and_test(RW_LOCK_BIAS, &rw->counter)) - return 1; - - atomic_add(RW_LOCK_BIAS, &rw->counter); + unsigned long tmp, oldval; + + __asm__ __volatile__ ( + "1: \n\t" + "movli.l @%2, %0 ! __raw_write_trylock \n\t" + "mov %0, %1 \n\t" + "cmp/hs %3, %0 \n\t" + "bf 2f \n\t" + "sub %3, %0 \n\t" + "2: \n\t" + "movco.l %0, @%2 \n\t" + "bf 1b \n\t" + "synco \n\t" + : "=&z" (tmp), "=&r" (oldval) + : "r" (&rw->lock), "r" (RW_LOCK_BIAS) + : "t", "memory" + ); - return 0; + return (oldval > (RW_LOCK_BIAS - 1)); } #define _raw_spin_relax(lock) cpu_relax() |