diff options
Diffstat (limited to 'arch/arm/include/asm/spinlock.h')
| -rw-r--r-- | arch/arm/include/asm/spinlock.h | 48 |
1 files changed, 44 insertions, 4 deletions
diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index 2b41ebbfa7ff..cfc6f6dc98c4 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h @@ -23,15 +23,38 @@ #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) +#ifdef CONFIG_ARM_ERRATA_351422 +#define spinlock_backoff_delay() \ +{ \ + unsigned int delay; \ + __asm__ __volatile__( \ + "1: mrc p15, 0, %0, c0, c0, 5\n" \ + " and %0, %0, #0xf\n" \ + " mov %0, %0, lsl #8\n" \ + "2: subs %0, %0, #1\n" \ + " bpl 2b\n" \ + : "=&r" (delay) \ + : \ + : "cc" ); \ +} +#else +#define spinlock_backoff_delay() \ + __asm__ __volatile__("1: \n"); +#endif + static inline void __raw_spin_lock(raw_spinlock_t *lock) { unsigned long tmp; + spinlock_backoff_delay(); __asm__ __volatile__( -"1: ldrex %0, [%1]\n" +" ldrex %0, [%1]\n" " teq %0, #0\n" #ifdef CONFIG_CPU_32v6K +" itee ne\n" " wfene\n" +#else +" itt eq\n" #endif " strexeq %0, %2, [%1]\n" " teqeq %0, #0\n" @@ -47,9 +70,11 @@ static inline int __raw_spin_trylock(raw_spinlock_t *lock) { unsigned long tmp; + spinlock_backoff_delay(); __asm__ __volatile__( " ldrex %0, [%1]\n" " teq %0, #0\n" +" it eq\n" " strexeq %0, %2, [%1]" : "=&r" (tmp) : "r" (&lock->lock), "r" (1) @@ -90,11 +115,15 @@ static inline void __raw_write_lock(raw_rwlock_t *rw) { unsigned long tmp; + spinlock_backoff_delay(); __asm__ __volatile__( -"1: ldrex %0, [%1]\n" +" ldrex %0, [%1]\n" " teq %0, #0\n" #ifdef CONFIG_CPU_32v6K +" ite ne\n" " wfene\n" +#else +" it eq\n" #endif " strexeq %0, %2, [%1]\n" " teq %0, #0\n" @@ -110,9 +139,11 @@ static inline int __raw_write_trylock(raw_rwlock_t *rw) { unsigned long tmp; + spinlock_backoff_delay(); __asm__ __volatile__( "1: ldrex %0, [%1]\n" " teq %0, #0\n" +" it eq\n" " strexeq %0, %2, [%1]" : "=&r" (tmp) : "r" (&rw->lock), "r" (0x80000000) @@ -160,9 +191,15 @@ static inline void __raw_read_lock(raw_rwlock_t *rw) { unsigned long tmp, tmp2; + spinlock_backoff_delay(); __asm__ __volatile__( -"1: ldrex %0, [%2]\n" +" ldrex %0, [%2]\n" " adds %0, %0, #1\n" +#ifdef CONFIG_CPU_32v6K +" itet pl\n" +#else +" itt pl\n" +#endif " strexpl %1, %0, [%2]\n" #ifdef CONFIG_CPU_32v6K " wfemi\n" @@ -182,14 +219,16 @@ static inline void __raw_read_unlock(raw_rwlock_t *rw) smp_mb(); + spinlock_backoff_delay(); __asm__ __volatile__( -"1: ldrex %0, [%2]\n" +" ldrex %0, [%2]\n" " sub %0, %0, #1\n" " strex %1, %0, [%2]\n" " teq %1, #0\n" " bne 1b" #ifdef CONFIG_CPU_32v6K "\n cmp %0, #0\n" +" itt eq\n" " mcreq p15, 0, %0, c7, c10, 4\n" " seveq" #endif @@ -205,6 +244,7 @@ static inline int __raw_read_trylock(raw_rwlock_t *rw) __asm__ __volatile__( "1: ldrex %0, [%2]\n" " adds %0, %0, #1\n" +" it pl\n" " strexpl %1, %0, [%2]\n" : "=&r" (tmp), "+r" (tmp2) : "r" (&rw->lock) |