Files
android/arch/sh/include/asm/barrier.h
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

46 lines
1.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
* Copyright (C) 2002 Paul Mundt
*/
#ifndef __ASM_SH_BARRIER_H
#define __ASM_SH_BARRIER_H
#if defined(CONFIG_CPU_SH4A) || defined(CONFIG_CPU_SH5)
#include <asm/cache_insns.h>
#endif
/*
* 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(CONFIG_CPU_SH4A) || defined(CONFIG_CPU_SH5)
#define mb() __asm__ __volatile__ ("synco": : :"memory")
#define rmb() mb()
#define wmb() mb()
#define ctrl_barrier() __icbi(PAGE_OFFSET)
#else
#if defined(CONFIG_CPU_J2) && defined(CONFIG_SMP)
#define __smp_mb() do { int tmp = 0; __asm__ __volatile__ ("cas.l %0,%0,@%1" : "+r"(tmp) : "z"(&tmp) : "memory", "t"); } while(0)
#define __smp_rmb() __smp_mb()
#define __smp_wmb() __smp_mb()
#endif
#define ctrl_barrier() __asm__ __volatile__ ("nop;nop;nop;nop;nop;nop;nop;nop")
#endif
#define __smp_store_mb(var, value) do { (void)xchg(&var, value); } while (0)
#include <asm-generic/barrier.h>
#endif /* __ASM_SH_BARRIER_H */