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-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 000000000000..5b04dd0aecab
--- /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 */