2 * Copyright 2012 Calxeda, Inc.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program. If not, see <http://www.gnu.org/licenses/>.
16 #ifndef _ASM_ARM_PERCPU_H_
17 #define _ASM_ARM_PERCPU_H_
19 #include <asm/thread_info.h>
22 * Same as asm-generic/percpu.h, except that we store the per cpu offset
23 * in the TPIDRPRW. TPIDRPRW only exists on V6K and V7
25 #if defined(CONFIG_SMP) && !defined(CONFIG_CPU_V6)
26 static inline void set_my_cpu_offset(unsigned long off)
29 asm volatile("mcr p15, 0, %0, c13, c0, 4" : : "r" (off) : "memory");
32 static inline unsigned long __my_cpu_offset(void)
38 * We want to allow caching the value, so avoid using volatile and
39 * instead use a fake stack read to hazard against barrier().
41 asm("mrc p15, 0, %0, c13, c0, 4" : "=r" (off)
42 : "Q" (*(const unsigned long *)current_stack_pointer));
46 #define __my_cpu_offset __my_cpu_offset()
48 #define set_my_cpu_offset(x) do {} while(0)
50 #endif /* CONFIG_SMP */
52 #include <asm-generic/percpu.h>
54 #endif /* _ASM_ARM_PERCPU_H_ */