/* * Spinlock support for the Hexagon architecture * * Copyright (c) 2010-2011, The Linux Foundation. All rights reserved. * * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 and * only version 2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301, USA. */ #ifndef _ASM_SPINLOCK_H #define _ASM_SPINLOCK_H #include <asm/irqflags.h> #include <asm/barrier.h> #include <asm/processor.h> /* * This file is pulled in for SMP builds. * Really need to check all the barrier stuff for "true" SMP */ /* * Read locks: * - load the lock value * - increment it * - if the lock value is still negative, go back and try again. * - unsuccessful store is unsuccessful. Go back and try again. Loser. * - successful store new lock value if positive -> lock acquired */ static inline void arch_read_lock(arch_rwlock_t *lock) { __asm__ __volatile__( "1: R6 = memw_locked(%0);\n" " { P3 = cmp.ge(R6,#0); R6 = add(R6,#1);}\n" " { if (!P3) jump 1b; }\n" " memw_locked(%0,P3) = R6;\n" " { if (!P3) jump 1b; }\n" : : "r" (&lock->lock) : "memory", "r6", "p3" ); } static inline void arch_read_unlock(arch_rwlock_t *lock) { __asm__ __volatile__( "1: R6 = memw_locked(%0);\n" " R6 = add(R6,#-1);\n" " memw_locked(%0,P3) = R6\n" " if (!P3) jump 1b;\n" : : "r" (&lock->lock) : "memory", "r6", "p3" ); } /* I think this returns 0 on fail, 1 on success. */ static inline int arch_read_trylock(arch_rwlock_t *lock) { int temp; __asm__ __volatile__( " R6 = memw_locked(%1);\n" " { %0 = #0; P3 = cmp.ge(R6,#0); R6 = add(R6,#1);}\n" " { if (!P3) jump 1f; }\n" " memw_locked(%1,P3) = R6;\n" " { %0 = P3 }\n" "1:\n" : "=&r" (temp) : "r" (&lock->lock) : "memory", "r6", "p3" ); return temp; } /* Stuffs a -1 in the lock value? */ static inline void arch_write_lock(arch_rwlock_t *lock) { __asm__ __volatile__( "1: R6 = memw_locked(%0)\n" " { P3 = cmp.eq(R6,#0); R6 = #-1;}\n" " { if (!P3) jump 1b; }\n" " memw_locked(%0,P3) = R6;\n" " { if (!P3) jump 1b; }\n" : : "r" (&lock->lock) : "memory", "r6", "p3" ); } static inline int arch_write_trylock(arch_rwlock_t *lock) { int temp; __asm__ __volatile__( " R6 = memw_locked(%1)\n" " { %0 = #0; P3 = cmp.eq(R6,#0); R6 = #-1;}\n" " { if (!P3) jump 1f; }\n" " memw_locked(%1,P3) = R6;\n" " %0 = P3;\n" "1:\n" : "=&r" (temp) : "r" (&lock->lock) : "memory", "r6", "p3" ); return temp; } static inline void arch_write_unlock(arch_rwlock_t *lock) { smp_mb(); lock->lock = 0; } static inline void arch_spin_lock(arch_spinlock_t *lock) { __asm__ __volatile__( "1: R6 = memw_locked(%0);\n" " P3 = cmp.eq(R6,#0);\n" " { if (!P3) jump 1b; R6 = #1; }\n" " memw_locked(%0,P3) = R6;\n" " { if (!P3) jump 1b; }\n" : : "r" (&lock->lock) : "memory", "r6", "p3" ); } static inline void arch_spin_unlock(arch_spinlock_t *lock) { smp_mb(); lock->lock = 0; } static inline unsigned int arch_spin_trylock(arch_spinlock_t *lock) { int temp; __asm__ __volatile__( " R6 = memw_locked(%1);\n" " P3 = cmp.eq(R6,#0);\n" " { if (!P3) jump 1f; R6 = #1; %0 = #0; }\n" " memw_locked(%1,P3) = R6;\n" " %0 = P3;\n" "1:\n" : "=&r" (temp) : "r" (&lock->lock) : "memory", "r6", "p3" ); return temp; } /* * SMP spinlocks are intended to allow only a single CPU at the lock */ #define arch_spin_is_locked(x) ((x)->lock != 0) #endif
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Kbuild | File | 886 B | 0644 |
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asm-offsets.h | File | 35 B | 0644 |
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atomic.h | File | 5.27 KB | 0644 |
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bitops.h | File | 6.62 KB | 0644 |
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cache.h | File | 1.16 KB | 0644 |
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cacheflush.h | File | 3.8 KB | 0644 |
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checksum.h | File | 1.61 KB | 0644 |
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cmpxchg.h | File | 2.55 KB | 0644 |
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delay.h | File | 978 B | 0644 |
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dma-mapping.h | File | 1.31 KB | 0644 |
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dma.h | File | 934 B | 0644 |
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elf.h | File | 6.34 KB | 0644 |
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exec.h | File | 1.01 KB | 0644 |
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fixmap.h | File | 1.11 KB | 0644 |
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fpu.h | File | 90 B | 0644 |
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futex.h | File | 2.25 KB | 0644 |
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hexagon_vm.h | File | 6.39 KB | 0644 |
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intrinsics.h | File | 1003 B | 0644 |
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io.h | File | 6.95 KB | 0644 |
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irq.h | File | 1.13 KB | 0644 |
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irqflags.h | File | 1.46 KB | 0644 |
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kgdb.h | File | 1.36 KB | 0644 |
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linkage.h | File | 871 B | 0644 |
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mem-layout.h | File | 3.42 KB | 0644 |
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mmu.h | File | 1.1 KB | 0644 |
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mmu_context.h | File | 2.59 KB | 0644 |
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module.h | File | 910 B | 0644 |
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page.h | File | 4.74 KB | 0644 |
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perf_event.h | File | 841 B | 0644 |
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pgalloc.h | File | 4.08 KB | 0644 |
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pgtable.h | File | 14.15 KB | 0644 |
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processor.h | File | 3.8 KB | 0644 |
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smp.h | File | 1.31 KB | 0644 |
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spinlock.h | File | 3.84 KB | 0644 |
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spinlock_types.h | File | 1.15 KB | 0644 |
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string.h | File | 1.08 KB | 0644 |
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suspend.h | File | 872 B | 0644 |
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switch_to.h | File | 1.09 KB | 0644 |
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syscall.h | File | 1.38 KB | 0644 |
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thread_info.h | File | 4.05 KB | 0644 |
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time.h | File | 980 B | 0644 |
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timer-regs.h | File | 1.23 KB | 0644 |
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timex.h | File | 1.13 KB | 0644 |
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tlb.h | File | 1.21 KB | 0644 |
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tlbflush.h | File | 2.08 KB | 0644 |
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traps.h | File | 1.02 KB | 0644 |
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uaccess.h | File | 3.67 KB | 0644 |
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vdso.h | File | 941 B | 0644 |
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vm_fault.h | File | 993 B | 0644 |
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vm_mmu.h | File | 3.37 KB | 0644 |
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