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 15 #define PPC_NOP_INSTR 0x60000000 16 #define PPC_LWSYNC_INSTR 0x7c2004ac 17 18 /* Flags for create_branch: 19 * "b" == create_branch(addr, target, 0); 20 * "ba" == create_branch(addr, target, BRANCH_ABSOLUTE); 21 * "bl" == create_branch(addr, target, BRANCH_SET_LINK); 22 * "bla" == create_branch(addr, target, BRANCH_ABSOLUTE | BRANCH_SET_LINK); 23 */ 24 #define BRANCH_SET_LINK 0x1 25 #define BRANCH_ABSOLUTE 0x2 26 27 unsigned int create_branch(const unsigned int *addr, 28 unsigned long target, int flags); 29 unsigned int create_cond_branch(const unsigned int *addr, 30 unsigned long target, int flags); 31 void patch_branch(unsigned int *addr, unsigned long target, int flags); 32 void patch_instruction(unsigned int *addr, unsigned int instr); 33 34 int instr_is_relative_branch(unsigned int instr); 35 int instr_is_branch_to_addr(const unsigned int *instr, unsigned long addr); 36 unsigned long branch_target(const unsigned int *instr); 37 unsigned int translate_branch(const unsigned int *dest, 38 const unsigned int *src); 39 40 static inline unsigned long ppc_function_entry(void *func) 41 { 42 #ifdef CONFIG_PPC64 43 /* 44 * On PPC64 the function pointer actually points to the function's 45 * descriptor. The first entry in the descriptor is the address 46 * of the function text. 47 */ 48 return ((func_descr_t *)func)->entry; 49 #else 50 return (unsigned long)func; 51 #endif 52 } 53 54 #endif /* _ASM_POWERPC_CODE_PATCHING_H */ 55