xref: /openbmc/linux/arch/powerpc/include/asm/sstep.h (revision 9cfc5c90)
1 /*
2  * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * as published by the Free Software Foundation; either version
7  * 2 of the License, or (at your option) any later version.
8  */
9 
10 struct pt_regs;
11 
12 /*
13  * We don't allow single-stepping an mtmsrd that would clear
14  * MSR_RI, since that would make the exception unrecoverable.
15  * Since we need to single-step to proceed from a breakpoint,
16  * we don't allow putting a breakpoint on an mtmsrd instruction.
17  * Similarly we don't allow breakpoints on rfid instructions.
18  * These macros tell us if an instruction is a mtmsrd or rfid.
19  * Note that IS_MTMSRD returns true for both an mtmsr (32-bit)
20  * and an mtmsrd (64-bit).
21  */
22 #define IS_MTMSRD(instr)	(((instr) & 0xfc0007be) == 0x7c000124)
23 #define IS_RFID(instr)		(((instr) & 0xfc0007fe) == 0x4c000024)
24 #define IS_RFI(instr)		(((instr) & 0xfc0007fe) == 0x4c000064)
25 
26 /* Emulate instructions that cause a transfer of control. */
27 extern int emulate_step(struct pt_regs *regs, unsigned int instr);
28 
29 enum instruction_type {
30 	COMPUTE,		/* arith/logical/CR op, etc. */
31 	LOAD,
32 	LOAD_MULTI,
33 	LOAD_FP,
34 	LOAD_VMX,
35 	LOAD_VSX,
36 	STORE,
37 	STORE_MULTI,
38 	STORE_FP,
39 	STORE_VMX,
40 	STORE_VSX,
41 	LARX,
42 	STCX,
43 	BRANCH,
44 	MFSPR,
45 	MTSPR,
46 	CACHEOP,
47 	BARRIER,
48 	SYSCALL,
49 	MFMSR,
50 	MTMSR,
51 	RFI,
52 	INTERRUPT,
53 	UNKNOWN
54 };
55 
56 #define INSTR_TYPE_MASK	0x1f
57 
58 /* Load/store flags, ORed in with type */
59 #define SIGNEXT		0x20
60 #define UPDATE		0x40	/* matches bit in opcode 31 instructions */
61 #define BYTEREV		0x80
62 
63 /* Cacheop values, ORed in with type */
64 #define CACHEOP_MASK	0x700
65 #define DCBST		0
66 #define DCBF		0x100
67 #define DCBTST		0x200
68 #define DCBT		0x300
69 #define ICBI		0x400
70 
71 /* Size field in type word */
72 #define SIZE(n)		((n) << 8)
73 #define GETSIZE(w)	((w) >> 8)
74 
75 #define MKOP(t, f, s)	((t) | (f) | SIZE(s))
76 
77 struct instruction_op {
78 	int type;
79 	int reg;
80 	unsigned long val;
81 	/* For LOAD/STORE/LARX/STCX */
82 	unsigned long ea;
83 	int update_reg;
84 	/* For MFSPR */
85 	int spr;
86 };
87 
88 extern int analyse_instr(struct instruction_op *op, struct pt_regs *regs,
89 			 unsigned int instr);
90