From c5113b61baf7a9a8616eca83e20847e7fecdc679 Mon Sep 17 00:00:00 2001 From: Rabin Vincent Date: Mon, 25 Jan 2010 19:43:03 +0100 Subject: [PATCH] ARM: 5897/1: spinlock: don't use deprecated barriers on ARMv7 On ARMv7, the use of the cp15 operations for barriers is deprecated in favour of the isb, dsb, and dmb instructions. Change the locking functions to use the appropriate type of dsb for the architecture being built for. Signed-off-by: Rabin Vincent Signed-off-by: Russell King --- arch/arm/include/asm/spinlock.h | 36 +++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 13 deletions(-) diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h index c91c64cab922..17eb355707dd 100644 --- a/arch/arm/include/asm/spinlock.h +++ b/arch/arm/include/asm/spinlock.h @@ -5,6 +5,22 @@ #error SMP not supported on pre-ARMv6 CPUs #endif +static inline void dsb_sev(void) +{ +#if __LINUX_ARM_ARCH__ >= 7 + __asm__ __volatile__ ( + "dsb\n" + "sev" + ); +#elif defined(CONFIG_CPU_32v6K) + __asm__ __volatile__ ( + "mcr p15, 0, %0, c7, c10, 4\n" + "sev" + : : "r" (0) + ); +#endif +} + /* * ARMv6 Spin-locking. * @@ -69,13 +85,11 @@ static inline void arch_spin_unlock(arch_spinlock_t *lock) __asm__ __volatile__( " str %1, [%0]\n" -#ifdef CONFIG_CPU_32v6K -" mcr p15, 0, %1, c7, c10, 4\n" /* DSB */ -" sev" -#endif : : "r" (&lock->lock), "r" (0) : "cc"); + + dsb_sev(); } /* @@ -132,13 +146,11 @@ static inline void arch_write_unlock(arch_rwlock_t *rw) __asm__ __volatile__( "str %1, [%0]\n" -#ifdef CONFIG_CPU_32v6K -" mcr p15, 0, %1, c7, c10, 4\n" /* DSB */ -" sev\n" -#endif : : "r" (&rw->lock), "r" (0) : "cc"); + + dsb_sev(); } /* write_can_lock - would write_trylock() succeed? */ @@ -188,14 +200,12 @@ static inline void arch_read_unlock(arch_rwlock_t *rw) " strex %1, %0, [%2]\n" " teq %1, #0\n" " bne 1b" -#ifdef CONFIG_CPU_32v6K -"\n cmp %0, #0\n" -" mcreq p15, 0, %0, c7, c10, 4\n" -" seveq" -#endif : "=&r" (tmp), "=&r" (tmp2) : "r" (&rw->lock) : "cc"); + + if (tmp == 0) + dsb_sev(); } static inline int arch_read_trylock(arch_rwlock_t *rw) -- 2.20.1