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Diffstat (limited to 'kernel/arch/mips/include/asm/barrier.h')
| -rw-r--r-- | kernel/arch/mips/include/asm/barrier.h | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/kernel/arch/mips/include/asm/barrier.h b/kernel/arch/mips/include/asm/barrier.h new file mode 100644 index 000000000..2b8bbbcb9 --- /dev/null +++ b/kernel/arch/mips/include/asm/barrier.h @@ -0,0 +1,150 @@ +/* + * 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 + * for more details. + * + * Copyright (C) 2006 by Ralf Baechle (ralf@linux-mips.org) + */ +#ifndef __ASM_BARRIER_H +#define __ASM_BARRIER_H + +#include <asm/addrspace.h> + +#define read_barrier_depends() do { } while(0) +#define smp_read_barrier_depends() do { } while(0) + +#ifdef CONFIG_CPU_HAS_SYNC +#define __sync() \ + __asm__ __volatile__( \ + ".set push\n\t" \ + ".set noreorder\n\t" \ + ".set mips2\n\t" \ + "sync\n\t" \ + ".set pop" \ + : /* no output */ \ + : /* no input */ \ + : "memory") +#else +#define __sync() do { } while(0) +#endif + +#define __fast_iob() \ + __asm__ __volatile__( \ + ".set push\n\t" \ + ".set noreorder\n\t" \ + "lw $0,%0\n\t" \ + "nop\n\t" \ + ".set pop" \ + : /* no output */ \ + : "m" (*(int *)CKSEG1) \ + : "memory") +#ifdef CONFIG_CPU_CAVIUM_OCTEON +# define OCTEON_SYNCW_STR ".set push\n.set arch=octeon\nsyncw\nsyncw\n.set pop\n" +# define __syncw() __asm__ __volatile__(OCTEON_SYNCW_STR : : : "memory") + +# define fast_wmb() __syncw() +# define fast_rmb() barrier() +# define fast_mb() __sync() +# define fast_iob() do { } while (0) +#else /* ! CONFIG_CPU_CAVIUM_OCTEON */ +# define fast_wmb() __sync() +# define fast_rmb() __sync() +# define fast_mb() __sync() +# ifdef CONFIG_SGI_IP28 +# define fast_iob() \ + __asm__ __volatile__( \ + ".set push\n\t" \ + ".set noreorder\n\t" \ + "lw $0,%0\n\t" \ + "sync\n\t" \ + "lw $0,%0\n\t" \ + ".set pop" \ + : /* no output */ \ + : "m" (*(int *)CKSEG1ADDR(0x1fa00004)) \ + : "memory") +# else +# define fast_iob() \ + do { \ + __sync(); \ + __fast_iob(); \ + } while (0) +# endif +#endif /* CONFIG_CPU_CAVIUM_OCTEON */ + +#ifdef CONFIG_CPU_HAS_WB + +#include <asm/wbflush.h> + +#define mb() wbflush() +#define iob() wbflush() + +#else /* !CONFIG_CPU_HAS_WB */ + +#define mb() fast_mb() +#define iob() fast_iob() + +#endif /* !CONFIG_CPU_HAS_WB */ + +#define wmb() fast_wmb() +#define rmb() fast_rmb() +#define dma_wmb() fast_wmb() +#define dma_rmb() fast_rmb() + +#if defined(CONFIG_WEAK_ORDERING) && defined(CONFIG_SMP) +# ifdef CONFIG_CPU_CAVIUM_OCTEON +# define smp_mb() __sync() +# define smp_rmb() barrier() +# define smp_wmb() __syncw() +# else +# define smp_mb() __asm__ __volatile__("sync" : : :"memory") +# define smp_rmb() __asm__ __volatile__("sync" : : :"memory") +# define smp_wmb() __asm__ __volatile__("sync" : : :"memory") +# endif +#else +#define smp_mb() barrier() +#define smp_rmb() barrier() +#define smp_wmb() barrier() +#endif + +#if defined(CONFIG_WEAK_REORDERING_BEYOND_LLSC) && defined(CONFIG_SMP) +#define __WEAK_LLSC_MB " sync \n" +#else +#define __WEAK_LLSC_MB " \n" +#endif + +#define set_mb(var, value) \ + do { var = value; smp_mb(); } while (0) + +#define smp_llsc_mb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory") + +#ifdef CONFIG_CPU_CAVIUM_OCTEON +#define smp_mb__before_llsc() smp_wmb() +/* Cause previous writes to become visible on all CPUs as soon as possible */ +#define nudge_writes() __asm__ __volatile__(".set push\n\t" \ + ".set arch=octeon\n\t" \ + "syncw\n\t" \ + ".set pop" : : : "memory") +#else +#define smp_mb__before_llsc() smp_llsc_mb() +#define nudge_writes() mb() +#endif + +#define smp_store_release(p, v) \ +do { \ + compiletime_assert_atomic_type(*p); \ + smp_mb(); \ + ACCESS_ONCE(*p) = (v); \ +} while (0) + +#define smp_load_acquire(p) \ +({ \ + typeof(*p) ___p1 = ACCESS_ONCE(*p); \ + compiletime_assert_atomic_type(*p); \ + smp_mb(); \ + ___p1; \ +}) + +#define smp_mb__before_atomic() smp_mb__before_llsc() +#define smp_mb__after_atomic() smp_llsc_mb() + +#endif /* __ASM_BARRIER_H */ |