diff options
Diffstat (limited to 'arch/frv/include/asm/cmpxchg.h')
| -rw-r--r-- | arch/frv/include/asm/cmpxchg.h | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/arch/frv/include/asm/cmpxchg.h b/arch/frv/include/asm/cmpxchg.h new file mode 100644 index 00000000000..5b04dd0aeca --- /dev/null +++ b/arch/frv/include/asm/cmpxchg.h @@ -0,0 +1,172 @@ +/* xchg and cmpxchg operation emulation for FR-V + * + * For an explanation of how atomic ops work in this arch, see: + * Documentation/frv/atomic-ops.txt + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ +#ifndef _ASM_CMPXCHG_H +#define _ASM_CMPXCHG_H + +#include <linux/types.h> + +/*****************************************************************************/ +/* + * exchange value with memory + */ +extern uint64_t __xchg_64(uint64_t i, volatile void *v); + +#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS + +#define xchg(ptr, x) \ +({ \ + __typeof__(ptr) __xg_ptr = (ptr); \ + __typeof__(*(ptr)) __xg_orig; \ + \ + switch (sizeof(__xg_orig)) { \ + case 4: \ + asm volatile( \ + "swap%I0 %M0,%1" \ + : "+m"(*__xg_ptr), "=r"(__xg_orig) \ + : "1"(x) \ + : "memory" \ + ); \ + break; \ + \ + default: \ + __xg_orig = (__typeof__(__xg_orig))0; \ + asm volatile("break"); \ + break; \ + } \ + \ + __xg_orig; \ +}) + +#else + +extern uint32_t __xchg_32(uint32_t i, volatile void *v); + +#define xchg(ptr, x) \ +({ \ + __typeof__(ptr) __xg_ptr = (ptr); \ + __typeof__(*(ptr)) __xg_orig; \ + \ + switch (sizeof(__xg_orig)) { \ + case 4: __xg_orig = (__typeof__(*(ptr))) __xchg_32((uint32_t) x, __xg_ptr); break; \ + default: \ + __xg_orig = (__typeof__(__xg_orig))0; \ + asm volatile("break"); \ + break; \ + } \ + __xg_orig; \ +}) + +#endif + +#define tas(ptr) (xchg((ptr), 1)) + +/*****************************************************************************/ +/* + * compare and conditionally exchange value with memory + * - if (*ptr == test) then orig = *ptr; *ptr = test; + * - if (*ptr != test) then orig = *ptr; + */ +extern uint64_t __cmpxchg_64(uint64_t test, uint64_t new, volatile uint64_t *v); + +#ifndef CONFIG_FRV_OUTOFLINE_ATOMIC_OPS + +#define cmpxchg(ptr, test, new) \ +({ \ + __typeof__(ptr) __xg_ptr = (ptr); \ + __typeof__(*(ptr)) __xg_orig, __xg_tmp; \ + __typeof__(*(ptr)) __xg_test = (test); \ + __typeof__(*(ptr)) __xg_new = (new); \ + \ + switch (sizeof(__xg_orig)) { \ + case 4: \ + asm volatile( \ + "0: \n" \ + " orcc gr0,gr0,gr0,icc3 \n" \ + " ckeq icc3,cc7 \n" \ + " ld.p %M0,%1 \n" \ + " orcr cc7,cc7,cc3 \n" \ + " sub%I4cc %1,%4,%2,icc0 \n" \ + " bne icc0,#0,1f \n" \ + " cst.p %3,%M0 ,cc3,#1 \n" \ + " corcc gr29,gr29,gr0 ,cc3,#1 \n" \ + " beq icc3,#0,0b \n" \ + "1: \n" \ + : "+U"(*__xg_ptr), "=&r"(__xg_orig), "=&r"(__xg_tmp) \ + : "r"(__xg_new), "NPr"(__xg_test) \ + : "memory", "cc7", "cc3", "icc3", "icc0" \ + ); \ + break; \ + \ + default: \ + __xg_orig = (__typeof__(__xg_orig))0; \ + asm volatile("break"); \ + break; \ + } \ + \ + __xg_orig; \ +}) + +#else + +extern uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new); + +#define cmpxchg(ptr, test, new) \ +({ \ + __typeof__(ptr) __xg_ptr = (ptr); \ + __typeof__(*(ptr)) __xg_orig; \ + __typeof__(*(ptr)) __xg_test = (test); \ + __typeof__(*(ptr)) __xg_new = (new); \ + \ + switch (sizeof(__xg_orig)) { \ + case 4: __xg_orig = (__force __typeof__(*ptr)) \ + __cmpxchg_32((__force uint32_t *)__xg_ptr, \ + (__force uint32_t)__xg_test, \ + (__force uint32_t)__xg_new); break; \ + default: \ + __xg_orig = (__typeof__(__xg_orig))0; \ + asm volatile("break"); \ + break; \ + } \ + \ + __xg_orig; \ +}) + +#endif + +#include <asm-generic/cmpxchg-local.h> + +static inline unsigned long __cmpxchg_local(volatile void *ptr, + unsigned long old, + unsigned long new, int size) +{ + switch (size) { + case 4: + return cmpxchg((unsigned long *)ptr, old, new); + default: + return __cmpxchg_local_generic(ptr, old, new, size); + } + + return old; +} + +/* + * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make + * them available. + */ +#define cmpxchg_local(ptr, o, n) \ + ((__typeof__(*(ptr)))__cmpxchg_local((ptr), (unsigned long)(o), \ + (unsigned long)(n), sizeof(*(ptr)))) +#define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) + +#endif /* _ASM_CMPXCHG_H */ |