1 #ifndef _ASM_POWERPC_CODE_PATCHING_H
2 #define _ASM_POWERPC_CODE_PATCHING_H
3
4 /*
5 * Copyright 2008, Michael Ellerman, IBM Corporation.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 */
12
13 #include <asm/types.h>
14 #include <asm/ppc-opcode.h>
15
16 /* Flags for create_branch:
17 * "b" == create_branch(addr, target, 0);
18 * "ba" == create_branch(addr, target, BRANCH_ABSOLUTE);
19 * "bl" == create_branch(addr, target, BRANCH_SET_LINK);
20 * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK);
21 */
22 #define BRANCH_SET_LINK 0x1
23 #define BRANCH_ABSOLUTE 0x2
24
25 unsigned int create_branch(const unsigned int *addr,
26 unsigned long target, int flags);
27 unsigned int create_cond_branch(const unsigned int *addr,
28 unsigned long target, int flags);
29 void patch_branch(unsigned int *addr, unsigned long target, int flags);
30 void patch_instruction(unsigned int *addr, unsigned int instr);
31
32 int instr_is_relative_branch(unsigned int instr);
33 int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr);
34 unsigned long branch_target(const unsigned int *instr);
35 unsigned int translate_branch(const unsigned int *dest,
36 const unsigned int *src);
37
ppc_function_entry(void * func)38 static inline unsigned long ppc_function_entry(void *func)
39 {
40 #ifdef CONFIG_PPC64
41 /*
42 * On PPC64 the function pointer actually points to the function's
43 * descriptor. The first entry in the descriptor is the address
44 * of the function text.
45 */
46 return ((func_descr_t *)func)->entry;
47 #else
48 return (unsigned long)func;
49 #endif
50 }
51
52 #endif /* _ASM_POWERPC_CODE_PATCHING_H */
53