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Diffstat (limited to 'include/asm-mips/barrier.h')
| -rw-r--r-- | include/asm-mips/barrier.h | 155 |
1 files changed, 0 insertions, 155 deletions
diff --git a/include/asm-mips/barrier.h b/include/asm-mips/barrier.h deleted file mode 100644 index 8e9ac313ca3..00000000000 --- a/include/asm-mips/barrier.h +++ /dev/null @@ -1,155 +0,0 @@ -/* - * 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 - -/* - * read_barrier_depends - Flush all pending reads that subsequents reads - * depend on. - * - * No data-dependent reads from memory-like regions are ever reordered - * over this barrier. All reads preceding this primitive are guaranteed - * to access memory (but not necessarily other CPUs' caches) before any - * reads following this primitive that depend on the data return by - * any of the preceding reads. This primitive is much lighter weight than - * rmb() on most CPUs, and is never heavier weight than is - * rmb(). - * - * These ordering constraints are respected by both the local CPU - * and the compiler. - * - * Ordering is not guaranteed by anything other than these primitives, - * not even by data dependencies. See the documentation for - * memory_barrier() for examples and URLs to more information. - * - * For example, the following code would force ordering (the initial - * value of "a" is zero, "b" is one, and "p" is "&a"): - * - * <programlisting> - * CPU 0 CPU 1 - * - * b = 2; - * memory_barrier(); - * p = &b; q = p; - * read_barrier_depends(); - * d = *q; - * </programlisting> - * - * because the read of "*q" depends on the read of "p" and these - * two reads are separated by a read_barrier_depends(). However, - * the following code, with the same initial values for "a" and "b": - * - * <programlisting> - * CPU 0 CPU 1 - * - * a = 2; - * memory_barrier(); - * b = 3; y = b; - * read_barrier_depends(); - * x = a; - * </programlisting> - * - * does not enforce ordering, since there is no data dependency between - * the read of "a" and the read of "b". Therefore, on some CPUs, such - * as Alpha, "y" could be set to 3 and "x" to 0. Use rmb() - * in cases like this where there are no data dependencies. - */ - -#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") - -#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 - -#ifdef CONFIG_CPU_HAS_WB - -#include <asm/wbflush.h> - -#define wmb() fast_wmb() -#define rmb() fast_rmb() -#define mb() wbflush() -#define iob() wbflush() - -#else /* !CONFIG_CPU_HAS_WB */ - -#define wmb() fast_wmb() -#define rmb() fast_rmb() -#define mb() fast_mb() -#define iob() fast_iob() - -#endif /* !CONFIG_CPU_HAS_WB */ - -#if defined(CONFIG_WEAK_ORDERING) && defined(CONFIG_SMP) -#define __WEAK_ORDERING_MB " sync \n" -#else -#define __WEAK_ORDERING_MB " \n" -#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 smp_mb() __asm__ __volatile__(__WEAK_ORDERING_MB : : :"memory") -#define smp_rmb() __asm__ __volatile__(__WEAK_ORDERING_MB : : :"memory") -#define smp_wmb() __asm__ __volatile__(__WEAK_ORDERING_MB : : :"memory") - -#define set_mb(var, value) \ - do { var = value; smp_mb(); } while (0) - -#define smp_llsc_mb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory") -#define smp_llsc_rmb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory") -#define smp_llsc_wmb() __asm__ __volatile__(__WEAK_LLSC_MB : : :"memory") - -#endif /* __ASM_BARRIER_H */ |