xref: /openbmc/linux/arch/arc/include/asm/disasm.h (revision 75bf465f0bc33e9b776a46d6a1b9b990f5fb7c37)
1  /* SPDX-License-Identifier: GPL-2.0-only */
2  /*
3   * several functions that help interpret ARC instructions
4   * used for unaligned accesses, kprobes and kgdb
5   *
6   * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
7   */
8  
9  #ifndef __ARC_DISASM_H__
10  #define __ARC_DISASM_H__
11  
12  enum {
13  	op_Bcc = 0, op_BLcc = 1, op_LD = 2, op_ST = 3, op_MAJOR_4 = 4,
14  	op_MAJOR_5 = 5, op_LD_ADD = 12, op_ADD_SUB_SHIFT = 13,
15  	op_ADD_MOV_CMP = 14, op_S = 15, op_LD_S = 16, op_LDB_S = 17,
16  	op_LDW_S = 18, op_LDWX_S = 19, op_ST_S = 20, op_STB_S = 21,
17  	op_STW_S = 22, op_Su5 = 23, op_SP = 24, op_GP = 25,
18  	op_Pcl = 26, op_MOV_S = 27, op_ADD_CMP = 28, op_BR_S = 29,
19  	op_B_S = 30, op_BL_S = 31
20  };
21  
22  enum flow {
23  	noflow,
24  	direct_jump,
25  	direct_call,
26  	indirect_jump,
27  	indirect_call,
28  	invalid_instr
29  };
30  
31  #define IS_BIT(word, n)		((word) & (1<<n))
32  #define BITS(word, s, e)	(((word) >> (s)) & (~((-2) << ((e) - (s)))))
33  
34  #define MAJOR_OPCODE(word)	(BITS((word), 27, 31))
35  #define MINOR_OPCODE(word)	(BITS((word), 16, 21))
36  #define FIELD_A(word)		(BITS((word), 0, 5))
37  #define FIELD_B(word)		((BITS((word), 12, 14)<<3) | \
38  				(BITS((word), 24, 26)))
39  #define FIELD_C(word)		(BITS((word), 6, 11))
40  #define FIELD_u6(word)		FIELDC(word)
41  #define FIELD_s12(word)		sign_extend(((BITS((word), 0, 5) << 6) | \
42  					BITS((word), 6, 11)), 12)
43  
44  /* note that for BL/BRcc these two macro's need another AND statement to mask
45   * out bit 1 (make the result a multiple of 4) */
46  #define FIELD_s9(word)		sign_extend(((BITS(word, 15, 15) << 8) | \
47  					BITS(word, 16, 23)), 9)
48  #define FIELD_s21(word)		sign_extend(((BITS(word, 6, 15) << 11) | \
49  					(BITS(word, 17, 26) << 1)), 12)
50  #define FIELD_s25(word)		sign_extend(((BITS(word, 0, 3) << 21) | \
51  					(BITS(word, 6, 15) << 11) | \
52  					(BITS(word, 17, 26) << 1)), 12)
53  
54  /* note: these operate on 16 bits! */
55  #define FIELD_S_A(word)		((BITS((word), 2, 2)<<3) | BITS((word), 0, 2))
56  #define FIELD_S_B(word)		((BITS((word), 10, 10)<<3) | \
57  				BITS((word), 8, 10))
58  #define FIELD_S_C(word)		((BITS((word), 7, 7)<<3) | BITS((word), 5, 7))
59  #define FIELD_S_H(word)		((BITS((word), 0, 2)<<3) | BITS((word), 5, 8))
60  #define FIELD_S_u5(word)	(BITS((word), 0, 4))
61  #define FIELD_S_u6(word)	(BITS((word), 0, 4) << 1)
62  #define FIELD_S_u7(word)	(BITS((word), 0, 4) << 2)
63  #define FIELD_S_u10(word)	(BITS((word), 0, 7) << 2)
64  #define FIELD_S_s7(word)	sign_extend(BITS((word), 0, 5) << 1, 9)
65  #define FIELD_S_s8(word)	sign_extend(BITS((word), 0, 7) << 1, 9)
66  #define FIELD_S_s9(word)	sign_extend(BITS((word), 0, 8), 9)
67  #define FIELD_S_s10(word)	sign_extend(BITS((word), 0, 8) << 1, 10)
68  #define FIELD_S_s11(word)	sign_extend(BITS((word), 0, 8) << 2, 11)
69  #define FIELD_S_s13(word)	sign_extend(BITS((word), 0, 10) << 2, 13)
70  
71  #define STATUS32_L		0x00000100
72  #define REG_LIMM		62
73  
74  struct disasm_state {
75  	/* generic info */
76  	unsigned long words[2];
77  	int instr_len;
78  	int major_opcode;
79  	/* info for branch/jump */
80  	int is_branch;
81  	int target;
82  	int delay_slot;
83  	enum flow flow;
84  	/* info for load/store */
85  	int src1, src2, src3, dest, wb_reg;
86  	int zz, aa, x, pref, di;
87  	int fault, write;
88  };
89  
sign_extend(int value,int bits)90  static inline int sign_extend(int value, int bits)
91  {
92  	if (IS_BIT(value, (bits - 1)))
93  		value |= (0xffffffff << bits);
94  
95  	return value;
96  }
97  
is_short_instr(unsigned long addr)98  static inline int is_short_instr(unsigned long addr)
99  {
100  	uint16_t word = *((uint16_t *)addr);
101  	int opcode = (word >> 11) & 0x1F;
102  	return (opcode >= 0x0B);
103  }
104  
105  void disasm_instr(unsigned long addr, struct disasm_state *state,
106  	int userspace, struct pt_regs *regs, struct callee_regs *cregs);
107  int disasm_next_pc(unsigned long pc, struct pt_regs *regs, struct callee_regs
108  	*cregs, unsigned long *fall_thru, unsigned long *target);
109  long get_reg(int reg, struct pt_regs *regs, struct callee_regs *cregs);
110  void set_reg(int reg, long val, struct pt_regs *regs,
111  		struct callee_regs *cregs);
112  
113  #endif	/* __ARC_DISASM_H__ */
114