91 lines
3.5 KiB
C
91 lines
3.5 KiB
C
|
/****************************************************************************
|
|||
|
|
* arch/arm64/include/spinlock.h
|
|||
|
|
*
|
|||
|
|
* Licensed to the Apache Software Foundation (ASF) under one or more
|
|||
|
|
* contributor license agreements. See the NOTICE file distributed with
|
|||
|
|
* this work for additional information regarding copyright ownership. The
|
|||
|
|
* ASF licenses this file to you under the Apache License, Version 2.0 (the
|
|||
|
|
* "License"); you may not use this file except in compliance with the
|
|||
|
|
* License. You may obtain a copy of the License at
|
|||
|
|
*
|
|||
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|||
|
|
*
|
|||
|
|
* Unless required by applicable law or agreed to in writing, software
|
|||
|
|
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
|
|||
|
|
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
|
|||
|
|
* License for the specific language governing permissions and limitations
|
|||
|
|
* under the License.
|
|||
|
|
*
|
|||
|
|
****************************************************************************/
|
|||
|
|
|
|||
|
|
#ifndef __ARCH_ARM64_INCLUDE_SPINLOCK_H
|
|||
|
|
#define __ARCH_ARM64_INCLUDE_SPINLOCK_H
|
|||
|
|
|
|||
|
|
/****************************************************************************
|
|||
|
|
* Included Files
|
|||
|
|
****************************************************************************/
|
|||
|
|
|
|||
|
|
#ifndef __ASSEMBLY__
|
|||
|
|
# include <stdint.h>
|
|||
|
|
#endif /* __ASSEMBLY__ */
|
|||
|
|
|
|||
|
|
/****************************************************************************
|
|||
|
|
* Pre-processor Prototypes
|
|||
|
|
****************************************************************************/
|
|||
|
|
|
|||
|
|
/* Spinlock states */
|
|||
|
|
|
|||
|
|
#define SP_UNLOCKED 0 /* The Un-locked state */
|
|||
|
|
#define SP_LOCKED 1 /* The Locked state */
|
|||
|
|
|
|||
|
|
/* Memory barriers for use with NuttX spinlock logic
|
|||
|
|
*
|
|||
|
|
* Data Memory Barrier (DMB) acts as a memory barrier. It ensures that all
|
|||
|
|
* explicit memory accesses that appear in program order before the DMB
|
|||
|
|
* instruction are observed before any explicit memory accesses that appear
|
|||
|
|
* in program order after the DMB instruction. It does not affect the
|
|||
|
|
* ordering of any other instructions executing on the processor
|
|||
|
|
*
|
|||
|
|
* dmb st - Data memory barrier. Wait for stores to complete.
|
|||
|
|
*
|
|||
|
|
* Data Synchronization Barrier (DSB) acts as a special kind of memory
|
|||
|
|
* barrier. No instruction in program order after this instruction executes
|
|||
|
|
* until this instruction completes. This instruction completes when: (1) All
|
|||
|
|
* explicit memory accesses before this instruction complete, and (2) all
|
|||
|
|
* Cache, Branch predictor and TLB maintenance operations before this
|
|||
|
|
* instruction complete.
|
|||
|
|
*
|
|||
|
|
* dsb sy - Data synchronization barrier. Assures that the CPU waits until
|
|||
|
|
* all memory accesses are complete
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
#define SP_DSB(n) __asm__ __volatile__ ("dsb sy" : : : "memory")
|
|||
|
|
#define SP_DMB(n) __asm__ __volatile__ ("dmb st" : : : "memory")
|
|||
|
|
|
|||
|
|
#define SP_WFE() __asm__ __volatile__ ("wfe" : : : "memory")
|
|||
|
|
#define SP_SEV() __asm__ __volatile__ ("sev" : : : "memory")
|
|||
|
|
|
|||
|
|
#ifndef __ASSEMBLY__
|
|||
|
|
|
|||
|
|
/* The Type of a spinlock.
|
|||
|
|
* ARM official document
|
|||
|
|
* ARM® Cortex®-A Series, Version: 1.0, Programmer’s Guide for ARMv8-A
|
|||
|
|
* ARM DEN0024A (ID050815)
|
|||
|
|
*
|
|||
|
|
* chapter 14.1.4 Synchronization
|
|||
|
|
*
|
|||
|
|
* The A64 instruction set has instructions for implementing
|
|||
|
|
* synchronization functions:
|
|||
|
|
* -- Load Exclusive (LDXR): LDXR W|Xt, [Xn]
|
|||
|
|
* -- Store Exclusive (STXR): STXR Ws, W|Xt, [Xn] where Ws
|
|||
|
|
* indicates whether the store completed successfully.
|
|||
|
|
* 0 = success.
|
|||
|
|
* -- Clear Exclusive access monitor (CLREX) This is used to
|
|||
|
|
* clear the state of the Local Exclusive Monitor.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
typedef uint64_t spinlock_t;
|
|||
|
|
|
|||
|
|
#endif /* __ASSEMBLY__ */
|
|||
|
|
#endif /* __ARCH_ARM64_INCLUDE_SPINLOCK_H */
|