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Diffstat (limited to 'arch/arm64/include/asm/percpu.h')
-rw-r--r-- | arch/arm64/include/asm/percpu.h | 49 |
1 files changed, 49 insertions, 0 deletions
diff --git a/arch/arm64/include/asm/percpu.h b/arch/arm64/include/asm/percpu.h new file mode 100644 index 000000000000..5279e5733386 --- /dev/null +++ b/arch/arm64/include/asm/percpu.h @@ -0,0 +1,49 @@ +/* + * Copyright (C) 2013 ARM Ltd. + * + * This program 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 program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#ifndef __ASM_PERCPU_H +#define __ASM_PERCPU_H + +#ifdef CONFIG_SMP + +static inline void set_my_cpu_offset(unsigned long off) +{ + asm volatile("msr tpidr_el1, %0" :: "r" (off) : "memory"); +} + +static inline unsigned long __my_cpu_offset(void) +{ + unsigned long off; + + /* + * We want to allow caching the value, so avoid using volatile and + * instead use a fake stack read to hazard against barrier(). + */ + asm("mrs %0, tpidr_el1" : "=r" (off) : + "Q" (*(const unsigned long *)current_stack_pointer)); + + return off; +} +#define __my_cpu_offset __my_cpu_offset() + +#else /* !CONFIG_SMP */ + +#define set_my_cpu_offset(x) do { } while (0) + +#endif /* CONFIG_SMP */ + +#include <asm-generic/percpu.h> + +#endif /* __ASM_PERCPU_H */ |