summaryrefslogtreecommitdiff
path: root/arch/frv/include/asm/cmpxchg.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/frv/include/asm/cmpxchg.h')
-rw-r--r--arch/frv/include/asm/cmpxchg.h172
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 000000000..5b04dd0ae
--- /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 */