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/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copied from the kernel sources:
*
* Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
* Copyright (C) 2002 Paul Mundt
*/
#ifndef __TOOLS_LINUX_ASM_SH_BARRIER_H
#define __TOOLS_LINUX_ASM_SH_BARRIER_H
/*
* A brief note on ctrl_barrier(), the control register write barrier.
*
* Legacy SH cores typically require a sequence of 8 nops after
* modification of a control register in order for the changes to take
* effect. On newer cores (like the sh4a and sh5) this is accomplished
* with icbi.
*
* Also note that on sh4a in the icbi case we can forego a synco for the
* write barrier, as it's not necessary for control registers.
*
* Historically we have only done this type of barrier for the MMUCR, but
* it's also necessary for the CCR, so we make it generic here instead.
*/
#if defined(__SH4A__)
#define mb() __asm__ __volatile__ ("synco": : :"memory")
#define rmb() mb()
#define wmb() mb()
#endif
#include <asm-generic/barrier.h>
#endif /* __TOOLS_LINUX_ASM_SH_BARRIER_H */
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