From b81947c646bfefdf98e2fde5d7d39cbbda8525d4 Mon Sep 17 00:00:00 2001 From: David Howells Date: Wed, 28 Mar 2012 18:30:02 +0100 Subject: Disintegrate asm/system.h for MIPS Disintegrate asm/system.h for MIPS. Signed-off-by: David Howells Acked-by: Ralf Baechle cc: linux-mips@linux-mips.org --- arch/mips/include/asm/cmpxchg.h | 124 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 124 insertions(+) (limited to 'arch/mips/include/asm/cmpxchg.h') diff --git a/arch/mips/include/asm/cmpxchg.h b/arch/mips/include/asm/cmpxchg.h index d8d1c2805ac7..285a41fa0b18 100644 --- a/arch/mips/include/asm/cmpxchg.h +++ b/arch/mips/include/asm/cmpxchg.h @@ -9,6 +9,130 @@ #define __ASM_CMPXCHG_H #include +#include + +static inline unsigned long __xchg_u32(volatile int * m, unsigned int val) +{ + __u32 retval; + + smp_mb__before_llsc(); + + if (kernel_uses_llsc && R10000_LLSC_WAR) { + unsigned long dummy; + + __asm__ __volatile__( + " .set mips3 \n" + "1: ll %0, %3 # xchg_u32 \n" + " .set mips0 \n" + " move %2, %z4 \n" + " .set mips3 \n" + " sc %2, %1 \n" + " beqzl %2, 1b \n" + " .set mips0 \n" + : "=&r" (retval), "=m" (*m), "=&r" (dummy) + : "R" (*m), "Jr" (val) + : "memory"); + } else if (kernel_uses_llsc) { + unsigned long dummy; + + do { + __asm__ __volatile__( + " .set mips3 \n" + " ll %0, %3 # xchg_u32 \n" + " .set mips0 \n" + " move %2, %z4 \n" + " .set mips3 \n" + " sc %2, %1 \n" + " .set mips0 \n" + : "=&r" (retval), "=m" (*m), "=&r" (dummy) + : "R" (*m), "Jr" (val) + : "memory"); + } while (unlikely(!dummy)); + } else { + unsigned long flags; + + raw_local_irq_save(flags); + retval = *m; + *m = val; + raw_local_irq_restore(flags); /* implies memory barrier */ + } + + smp_llsc_mb(); + + return retval; +} + +#ifdef CONFIG_64BIT +static inline __u64 __xchg_u64(volatile __u64 * m, __u64 val) +{ + __u64 retval; + + smp_mb__before_llsc(); + + if (kernel_uses_llsc && R10000_LLSC_WAR) { + unsigned long dummy; + + __asm__ __volatile__( + " .set mips3 \n" + "1: lld %0, %3 # xchg_u64 \n" + " move %2, %z4 \n" + " scd %2, %1 \n" + " beqzl %2, 1b \n" + " .set mips0 \n" + : "=&r" (retval), "=m" (*m), "=&r" (dummy) + : "R" (*m), "Jr" (val) + : "memory"); + } else if (kernel_uses_llsc) { + unsigned long dummy; + + do { + __asm__ __volatile__( + " .set mips3 \n" + " lld %0, %3 # xchg_u64 \n" + " move %2, %z4 \n" + " scd %2, %1 \n" + " .set mips0 \n" + : "=&r" (retval), "=m" (*m), "=&r" (dummy) + : "R" (*m), "Jr" (val) + : "memory"); + } while (unlikely(!dummy)); + } else { + unsigned long flags; + + raw_local_irq_save(flags); + retval = *m; + *m = val; + raw_local_irq_restore(flags); /* implies memory barrier */ + } + + smp_llsc_mb(); + + return retval; +} +#else +extern __u64 __xchg_u64_unsupported_on_32bit_kernels(volatile __u64 * m, __u64 val); +#define __xchg_u64 __xchg_u64_unsupported_on_32bit_kernels +#endif + +static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) +{ + switch (size) { + case 4: + return __xchg_u32(ptr, x); + case 8: + return __xchg_u64(ptr, x); + } + + return x; +} + +#define xchg(ptr, x) \ +({ \ + BUILD_BUG_ON(sizeof(*(ptr)) & ~0xc); \ + \ + ((__typeof__(*(ptr))) \ + __xchg((unsigned long)(x), (ptr), sizeof(*(ptr)))); \ +}) #define __HAVE_ARCH_CMPXCHG 1 -- cgit v1.2.1