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diff --git a/arch/mips/include/asm/octeon/cvmx-spinlock.h b/arch/mips/include/asm/octeon/cvmx-spinlock.h
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+/***********************license start***************
+ * Author: Cavium Networks
+ *
+ * Contact: support@caviumnetworks.com
+ * This file is part of the OCTEON SDK
+ *
+ * Copyright (c) 2003-2008 Cavium Networks
+ *
+ * This file is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License, Version 2, as
+ * published by the Free Software Foundation.
+ *
+ * This file is distributed in the hope that it will be useful, but
+ * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
+ * NONINFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this file; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ * or visit http://www.gnu.org/licenses/.
+ *
+ * This file may also be available under a different license from Cavium.
+ * Contact Cavium Networks for more information
+ ***********************license end**************************************/
+
+/**
+ * Implementation of spinlocks for Octeon CVMX. Although similar in
+ * function to Linux kernel spinlocks, they are not compatible.
+ * Octeon CVMX spinlocks are only used to synchronize with the boot
+ * monitor and other non-Linux programs running in the system.
+ */
+
+#ifndef __CVMX_SPINLOCK_H__
+#define __CVMX_SPINLOCK_H__
+
+#include "cvmx-asm.h"
+
+/* Spinlocks for Octeon */
+
+/* define these to enable recursive spinlock debugging */
+/*#define CVMX_SPINLOCK_DEBUG */
+
+/**
+ * Spinlocks for Octeon CVMX
+ */
+typedef struct {
+ volatile uint32_t value;
+} cvmx_spinlock_t;
+
+/* note - macros not expanded in inline ASM, so values hardcoded */
+#define CVMX_SPINLOCK_UNLOCKED_VAL 0
+#define CVMX_SPINLOCK_LOCKED_VAL 1
+
+#define CVMX_SPINLOCK_UNLOCKED_INITIALIZER {CVMX_SPINLOCK_UNLOCKED_VAL}
+
+/**
+ * Initialize a spinlock
+ *
+ * @lock: Lock to initialize
+ */
+static inline void cvmx_spinlock_init(cvmx_spinlock_t *lock)
+{
+ lock->value = CVMX_SPINLOCK_UNLOCKED_VAL;
+}
+
+/**
+ * Return non-zero if the spinlock is currently locked
+ *
+ * @lock: Lock to check
+ * Returns Non-zero if locked
+ */
+static inline int cvmx_spinlock_locked(cvmx_spinlock_t *lock)
+{
+ return lock->value != CVMX_SPINLOCK_UNLOCKED_VAL;
+}
+
+/**
+ * Releases lock
+ *
+ * @lock: pointer to lock structure
+ */
+static inline void cvmx_spinlock_unlock(cvmx_spinlock_t *lock)
+{
+ CVMX_SYNCWS;
+ lock->value = 0;
+ CVMX_SYNCWS;
+}
+
+/**
+ * Attempts to take the lock, but does not spin if lock is not available.
+ * May take some time to acquire the lock even if it is available
+ * due to the ll/sc not succeeding.
+ *
+ * @lock: pointer to lock structure
+ *
+ * Returns 0: lock successfully taken
+ * 1: lock not taken, held by someone else
+ * These return values match the Linux semantics.
+ */
+
+static inline unsigned int cvmx_spinlock_trylock(cvmx_spinlock_t *lock)
+{
+ unsigned int tmp;
+
+ __asm__ __volatile__(".set noreorder \n"
+ "1: ll %[tmp], %[val] \n"
+ /* if lock held, fail immediately */
+ " bnez %[tmp], 2f \n"
+ " li %[tmp], 1 \n"
+ " sc %[tmp], %[val] \n"
+ " beqz %[tmp], 1b \n"
+ " li %[tmp], 0 \n"
+ "2: \n"
+ ".set reorder \n" :
+ [val] "+m"(lock->value), [tmp] "=&r"(tmp)
+ : : "memory");
+
+ return tmp != 0; /* normalize to 0 or 1 */
+}
+
+/**
+ * Gets lock, spins until lock is taken
+ *
+ * @lock: pointer to lock structure
+ */
+static inline void cvmx_spinlock_lock(cvmx_spinlock_t *lock)
+{
+ unsigned int tmp;
+
+ __asm__ __volatile__(".set noreorder \n"
+ "1: ll %[tmp], %[val] \n"
+ " bnez %[tmp], 1b \n"
+ " li %[tmp], 1 \n"
+ " sc %[tmp], %[val] \n"
+ " beqz %[tmp], 1b \n"
+ " nop \n"
+ ".set reorder \n" :
+ [val] "+m"(lock->value), [tmp] "=&r"(tmp)
+ : : "memory");
+
+}
+
+/** ********************************************************************
+ * Bit spinlocks
+ * These spinlocks use a single bit (bit 31) of a 32 bit word for locking.
+ * The rest of the bits in the word are left undisturbed. This enables more
+ * compact data structures as only 1 bit is consumed for the lock.
+ *
+ */
+
+/**
+ * Gets lock, spins until lock is taken
+ * Preserves the low 31 bits of the 32 bit
+ * word used for the lock.
+ *
+ *
+ * @word: word to lock bit 31 of
+ */
+static inline void cvmx_spinlock_bit_lock(uint32_t *word)
+{
+ unsigned int tmp;
+ unsigned int sav;
+
+ __asm__ __volatile__(".set noreorder \n"
+ ".set noat \n"
+ "1: ll %[tmp], %[val] \n"
+ " bbit1 %[tmp], 31, 1b \n"
+ " li $at, 1 \n"
+ " ins %[tmp], $at, 31, 1 \n"
+ " sc %[tmp], %[val] \n"
+ " beqz %[tmp], 1b \n"
+ " nop \n"
+ ".set at \n"
+ ".set reorder \n" :
+ [val] "+m"(*word), [tmp] "=&r"(tmp), [sav] "=&r"(sav)
+ : : "memory");
+
+}
+
+/**
+ * Attempts to get lock, returns immediately with success/failure
+ * Preserves the low 31 bits of the 32 bit
+ * word used for the lock.
+ *
+ *
+ * @word: word to lock bit 31 of
+ * Returns 0: lock successfully taken
+ * 1: lock not taken, held by someone else
+ * These return values match the Linux semantics.
+ */
+static inline unsigned int cvmx_spinlock_bit_trylock(uint32_t *word)
+{
+ unsigned int tmp;
+
+ __asm__ __volatile__(".set noreorder\n\t"
+ ".set noat\n"
+ "1: ll %[tmp], %[val] \n"
+ /* if lock held, fail immediately */
+ " bbit1 %[tmp], 31, 2f \n"
+ " li $at, 1 \n"
+ " ins %[tmp], $at, 31, 1 \n"
+ " sc %[tmp], %[val] \n"
+ " beqz %[tmp], 1b \n"
+ " li %[tmp], 0 \n"
+ "2: \n"
+ ".set at \n"
+ ".set reorder \n" :
+ [val] "+m"(*word), [tmp] "=&r"(tmp)
+ : : "memory");
+
+ return tmp != 0; /* normalize to 0 or 1 */
+}
+
+/**
+ * Releases bit lock
+ *
+ * Unconditionally clears bit 31 of the lock word. Note that this is
+ * done non-atomically, as this implementation assumes that the rest
+ * of the bits in the word are protected by the lock.
+ *
+ * @word: word to unlock bit 31 in
+ */
+static inline void cvmx_spinlock_bit_unlock(uint32_t *word)
+{
+ CVMX_SYNCWS;
+ *word &= ~(1UL << 31);
+ CVMX_SYNCWS;
+}
+
+#endif /* __CVMX_SPINLOCK_H__ */
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