linux/arch/sh/include/asm/mmiowb.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ASM_SH_MMIOWB_H
#define __ASM_SH_MMIOWB_H

#include <asm/barrier.h>

/* synco on SH-4A, otherwise a nop */
#define mmiowb()			wmb()

#include <asm-generic/mmiowb.h>

#endif	/* __ASM_SH_MMIOWB_H */
sh/mmiowb: Add unconditional mmiowb() to arch_spin_unlock() The mmiowb() macro is horribly difficult to use and drivers will continue to work most of the time if they omit a call when it is required. Rather than rely on driver authors getting this right, push mmiowb() into arch_spin_unlock() for sh. If this is deemed to be a performance issue, a subsequent optimisation could make use of ARCH_HAS_MMIOWB to elide the barrier in cases where no I/O writes were performed inside the critical section. Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Rich Felker <dalias@libc.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com> 2019-02-22 21:37:21 +08:00			`/* SPDX-License-Identifier: GPL-2.0 */`
			`#ifndef __ASM_SH_MMIOWB_H`
			`#define __ASM_SH_MMIOWB_H`

			`#include <asm/barrier.h>`

			`/* synco on SH-4A, otherwise a nop */`
			`#define mmiowb() wmb()`

			`#include <asm-generic/mmiowb.h>`

			`#endif /* __ASM_SH_MMIOWB_H */`