1 files changed, 54 insertions, 0 deletions
diff --git a/include/asm-powerpc/code-patching.h b/include/asm-powerpc/code-patching.h
new file mode 100644
index 00000000000..107d9b915e3
--- /dev/null
+++ b/include/asm-powerpc/code-patching.h
@@ -0,0 +1,54 @@
+#ifndef _ASM_POWERPC_CODE_PATCHING_H
+#define _ASM_POWERPC_CODE_PATCHING_H
+
+/*
+ * Copyright 2008, Michael Ellerman, IBM Corporation.
+ *
+ * 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.
+ */
+
+#include <asm/types.h>
+
+#define PPC_NOP_INSTR		0x60000000
+#define PPC_LWSYNC_INSTR	0x7c2004ac
+
+/* Flags for create_branch:
+ * "b"   == create_branch(addr, target, 0);
+ * "ba"  == create_branch(addr, target, BRANCH_ABSOLUTE);
+ * "bl"  == create_branch(addr, target, BRANCH_SET_LINK);
+ * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
+ */
+#define BRANCH_SET_LINK	0x1
+#define BRANCH_ABSOLUTE	0x2
+
+unsigned int create_branch(const unsigned int *addr,
+			   unsigned long target, int flags);
+unsigned int create_cond_branch(const unsigned int *addr,
+				unsigned long target, int flags);
+void patch_branch(unsigned int *addr, unsigned long target, int flags);
+void patch_instruction(unsigned int *addr, unsigned int instr);
+
+int instr_is_relative_branch(unsigned int instr);
+int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr);
+unsigned long branch_target(const unsigned int *instr);
+unsigned int translate_branch(const unsigned int *dest,
+			      const unsigned int *src);
+
+static inline unsigned long ppc_function_entry(void *func)
+{
+#ifdef CONFIG_PPC64
+	/*
+	 * On PPC64 the function pointer actually points to the function's
+	 * descriptor. The first entry in the descriptor is the address
+	 * of the function text.
+	 */
+	return ((func_descr_t *)func)->entry;
+#else
+	return (unsigned long)func;
+#endif
+}
+
+#endif /* _ASM_POWERPC_CODE_PATCHING_H */