/* * Atomic xchg and cmpxchg operations. * * 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) 2001 - 2005 Tensilica Inc. */ #ifndef _XTENSA_CMPXCHG_H #define _XTENSA_CMPXCHG_H #ifndef __ASSEMBLY__ #include <linux/stringify.h> /* * cmpxchg */ static inline unsigned long __cmpxchg_u32(volatile int *p, int old, int new) { #if XCHAL_HAVE_S32C1I __asm__ __volatile__( " wsr %2, scompare1\n" " s32c1i %0, %1, 0\n" : "+a" (new) : "a" (p), "a" (old) : "memory" ); return new; #else __asm__ __volatile__( " rsil a15, "__stringify(TOPLEVEL)"\n" " l32i %0, %1, 0\n" " bne %0, %2, 1f\n" " s32i %3, %1, 0\n" "1:\n" " wsr a15, ps\n" " rsync\n" : "=&a" (old) : "a" (p), "a" (old), "r" (new) : "a15", "memory"); return old; #endif } /* This function doesn't exist, so you'll get a linker error * if something tries to do an invalid cmpxchg(). */ extern void __cmpxchg_called_with_bad_pointer(void); static __inline__ unsigned long __cmpxchg(volatile void *ptr, unsigned long old, unsigned long new, int size) { switch (size) { case 4: return __cmpxchg_u32(ptr, old, new); default: __cmpxchg_called_with_bad_pointer(); return old; } } #define cmpxchg(ptr,o,n) \ ({ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \ (unsigned long)_n_, sizeof (*(ptr))); \ }) #include <asm-generic/cmpxchg-local.h> static inline unsigned long __cmpxchg_local(volatile void *ptr, unsigned long old, unsigned long new, int size) { switch (size) { case 4: return __cmpxchg_u32(ptr, old, new); default: return __cmpxchg_local_generic(ptr, old, new, size); } return old; } /* * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make * them available. */ #define cmpxchg_local(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ (unsigned long)(n), sizeof(*(ptr)))) #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n)) /* * xchg_u32 * * Note that a15 is used here because the register allocation * done by the compiler is not guaranteed and a window overflow * may not occur between the rsil and wsr instructions. By using * a15 in the rsil, the machine is guaranteed to be in a state * where no register reference will cause an overflow. */ static inline unsigned long xchg_u32(volatile int * m, unsigned long val) { #if XCHAL_HAVE_S32C1I unsigned long tmp, result; __asm__ __volatile__( "1: l32i %1, %2, 0\n" " mov %0, %3\n" " wsr %1, scompare1\n" " s32c1i %0, %2, 0\n" " bne %0, %1, 1b\n" : "=&a" (result), "=&a" (tmp) : "a" (m), "a" (val) : "memory" ); return result; #else unsigned long tmp; __asm__ __volatile__( " rsil a15, "__stringify(TOPLEVEL)"\n" " l32i %0, %1, 0\n" " s32i %2, %1, 0\n" " wsr a15, ps\n" " rsync\n" : "=&a" (tmp) : "a" (m), "a" (val) : "a15", "memory"); return tmp; #endif } #define xchg(ptr,x) \ ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) /* * This only works if the compiler isn't horribly bad at optimizing. * gcc-2.5.8 reportedly can't handle this, but I define that one to * be dead anyway. */ extern void __xchg_called_with_bad_pointer(void); static __inline__ unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { switch (size) { case 4: return xchg_u32(ptr, x); } __xchg_called_with_bad_pointer(); return x; } #endif /* __ASSEMBLY__ */ #endif /* _XTENSA_CMPXCHG_H */
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Kbuild | File | 685 B | 0644 |
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asm-offsets.h | File | 35 B | 0644 |
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asm-uaccess.h | File | 4.11 KB | 0644 |
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asmmacro.h | File | 2.76 KB | 0644 |
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atomic.h | File | 7.38 KB | 0644 |
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barrier.h | File | 542 B | 0644 |
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bitops.h | File | 5.08 KB | 0644 |
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bootparam.h | File | 1.37 KB | 0644 |
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bugs.h | File | 451 B | 0644 |
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cache.h | File | 969 B | 0644 |
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cacheasm.h | File | 3.77 KB | 0644 |
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cacheflush.h | File | 5.76 KB | 0644 |
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checksum.h | File | 6 KB | 0644 |
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cmpxchg.h | File | 3.9 KB | 0644 |
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coprocessor.h | File | 5.05 KB | 0644 |
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current.h | File | 675 B | 0644 |
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delay.h | File | 1.63 KB | 0644 |
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dma-mapping.h | File | 855 B | 0644 |
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dma.h | File | 1.79 KB | 0644 |
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elf.h | File | 5.75 KB | 0644 |
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fixmap.h | File | 2.5 KB | 0644 |
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flat.h | File | 686 B | 0644 |
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ftrace.h | File | 979 B | 0644 |
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futex.h | File | 2.59 KB | 0644 |
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highmem.h | File | 2.33 KB | 0644 |
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hw_breakpoint.h | File | 1.45 KB | 0644 |
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hw_irq.h | File | 320 B | 0644 |
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initialize_mmu.h | File | 4.58 KB | 0644 |
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io.h | File | 2.09 KB | 0644 |
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irq.h | File | 1.46 KB | 0644 |
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irqflags.h | File | 1.99 KB | 0644 |
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kmem_layout.h | File | 2.07 KB | 0644 |
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mmu.h | File | 462 B | 0644 |
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mmu_context.h | File | 3.62 KB | 0644 |
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module.h | File | 525 B | 0644 |
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mxregs.h | File | 1.3 KB | 0644 |
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nommu_context.h | File | 602 B | 0644 |
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page.h | File | 5.69 KB | 0644 |
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pci-bridge.h | File | 2.16 KB | 0644 |
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pci.h | File | 1.37 KB | 0644 |
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perf_event.h | File | 108 B | 0644 |
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pgalloc.h | File | 1.84 KB | 0644 |
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pgtable.h | File | 14.89 KB | 0644 |
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platform.h | File | 1.75 KB | 0644 |
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processor.h | File | 7.44 KB | 0644 |
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ptrace.h | File | 3.74 KB | 0644 |
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regs.h | File | 3.87 KB | 0644 |
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segment.h | File | 376 B | 0644 |
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serial.h | File | 443 B | 0644 |
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shmparam.h | File | 561 B | 0644 |
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signal.h | File | 502 B | 0644 |
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smp.h | File | 967 B | 0644 |
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spinlock.h | File | 4.6 KB | 0644 |
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spinlock_types.h | File | 412 B | 0644 |
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stacktrace.h | File | 1.13 KB | 0644 |
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string.h | File | 2.65 KB | 0644 |
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switch_to.h | File | 601 B | 0644 |
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syscall.h | File | 982 B | 0644 |
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sysmem.h | File | 426 B | 0644 |
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thread_info.h | File | 3.62 KB | 0644 |
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timex.h | File | 1.79 KB | 0644 |
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tlb.h | File | 1.1 KB | 0644 |
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tlbflush.h | File | 5.53 KB | 0644 |
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traps.h | File | 1.87 KB | 0644 |
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types.h | File | 501 B | 0644 |
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uaccess.h | File | 8.67 KB | 0644 |
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ucontext.h | File | 540 B | 0644 |
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unaligned.h | File | 864 B | 0644 |
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unistd.h | File | 639 B | 0644 |
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user.h | File | 507 B | 0644 |
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vectors.h | File | 4.05 KB | 0644 |
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vga.h | File | 434 B | 0644 |
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