diff options
Diffstat (limited to 'arch/ppc64/lib/sstep.c')
-rw-r--r-- | arch/ppc64/lib/sstep.c | 141 |
1 files changed, 0 insertions, 141 deletions
diff --git a/arch/ppc64/lib/sstep.c b/arch/ppc64/lib/sstep.c deleted file mode 100644 index e79123d1485c..000000000000 --- a/arch/ppc64/lib/sstep.c +++ /dev/null | |||
@@ -1,141 +0,0 @@ | |||
1 | /* | ||
2 | * Single-step support. | ||
3 | * | ||
4 | * Copyright (C) 2004 Paul Mackerras <paulus@au.ibm.com>, IBM | ||
5 | * | ||
6 | * This program is free software; you can redistribute it and/or | ||
7 | * modify it under the terms of the GNU General Public License | ||
8 | * as published by the Free Software Foundation; either version | ||
9 | * 2 of the License, or (at your option) any later version. | ||
10 | */ | ||
11 | #include <linux/kernel.h> | ||
12 | #include <linux/ptrace.h> | ||
13 | #include <asm/sstep.h> | ||
14 | #include <asm/processor.h> | ||
15 | |||
16 | extern char system_call_common[]; | ||
17 | |||
18 | /* Bits in SRR1 that are copied from MSR */ | ||
19 | #define MSR_MASK 0xffffffff87c0ffff | ||
20 | |||
21 | /* | ||
22 | * Determine whether a conditional branch instruction would branch. | ||
23 | */ | ||
24 | static int branch_taken(unsigned int instr, struct pt_regs *regs) | ||
25 | { | ||
26 | unsigned int bo = (instr >> 21) & 0x1f; | ||
27 | unsigned int bi; | ||
28 | |||
29 | if ((bo & 4) == 0) { | ||
30 | /* decrement counter */ | ||
31 | --regs->ctr; | ||
32 | if (((bo >> 1) & 1) ^ (regs->ctr == 0)) | ||
33 | return 0; | ||
34 | } | ||
35 | if ((bo & 0x10) == 0) { | ||
36 | /* check bit from CR */ | ||
37 | bi = (instr >> 16) & 0x1f; | ||
38 | if (((regs->ccr >> (31 - bi)) & 1) != ((bo >> 3) & 1)) | ||
39 | return 0; | ||
40 | } | ||
41 | return 1; | ||
42 | } | ||
43 | |||
44 | /* | ||
45 | * Emulate instructions that cause a transfer of control. | ||
46 | * Returns 1 if the step was emulated, 0 if not, | ||
47 | * or -1 if the instruction is one that should not be stepped, | ||
48 | * such as an rfid, or a mtmsrd that would clear MSR_RI. | ||
49 | */ | ||
50 | int emulate_step(struct pt_regs *regs, unsigned int instr) | ||
51 | { | ||
52 | unsigned int opcode, rd; | ||
53 | unsigned long int imm; | ||
54 | |||
55 | opcode = instr >> 26; | ||
56 | switch (opcode) { | ||
57 | case 16: /* bc */ | ||
58 | imm = (signed short)(instr & 0xfffc); | ||
59 | if ((instr & 2) == 0) | ||
60 | imm += regs->nip; | ||
61 | regs->nip += 4; | ||
62 | if ((regs->msr & MSR_SF) == 0) | ||
63 | regs->nip &= 0xffffffffUL; | ||
64 | if (instr & 1) | ||
65 | regs->link = regs->nip; | ||
66 | if (branch_taken(instr, regs)) | ||
67 | regs->nip = imm; | ||
68 | return 1; | ||
69 | case 17: /* sc */ | ||
70 | /* | ||
71 | * N.B. this uses knowledge about how the syscall | ||
72 | * entry code works. If that is changed, this will | ||
73 | * need to be changed also. | ||
74 | */ | ||
75 | regs->gpr[9] = regs->gpr[13]; | ||
76 | regs->gpr[11] = regs->nip + 4; | ||
77 | regs->gpr[12] = regs->msr & MSR_MASK; | ||
78 | regs->gpr[13] = (unsigned long) get_paca(); | ||
79 | regs->nip = (unsigned long) &system_call_common; | ||
80 | regs->msr = MSR_KERNEL; | ||
81 | return 1; | ||
82 | case 18: /* b */ | ||
83 | imm = instr & 0x03fffffc; | ||
84 | if (imm & 0x02000000) | ||
85 | imm -= 0x04000000; | ||
86 | if ((instr & 2) == 0) | ||
87 | imm += regs->nip; | ||
88 | if (instr & 1) { | ||
89 | regs->link = regs->nip + 4; | ||
90 | if ((regs->msr & MSR_SF) == 0) | ||
91 | regs->link &= 0xffffffffUL; | ||
92 | } | ||
93 | if ((regs->msr & MSR_SF) == 0) | ||
94 | imm &= 0xffffffffUL; | ||
95 | regs->nip = imm; | ||
96 | return 1; | ||
97 | case 19: | ||
98 | switch (instr & 0x7fe) { | ||
99 | case 0x20: /* bclr */ | ||
100 | case 0x420: /* bcctr */ | ||
101 | imm = (instr & 0x400)? regs->ctr: regs->link; | ||
102 | regs->nip += 4; | ||
103 | if ((regs->msr & MSR_SF) == 0) { | ||
104 | regs->nip &= 0xffffffffUL; | ||
105 | imm &= 0xffffffffUL; | ||
106 | } | ||
107 | if (instr & 1) | ||
108 | regs->link = regs->nip; | ||
109 | if (branch_taken(instr, regs)) | ||
110 | regs->nip = imm; | ||
111 | return 1; | ||
112 | case 0x24: /* rfid, scary */ | ||
113 | return -1; | ||
114 | } | ||
115 | case 31: | ||
116 | rd = (instr >> 21) & 0x1f; | ||
117 | switch (instr & 0x7fe) { | ||
118 | case 0xa6: /* mfmsr */ | ||
119 | regs->gpr[rd] = regs->msr & MSR_MASK; | ||
120 | regs->nip += 4; | ||
121 | if ((regs->msr & MSR_SF) == 0) | ||
122 | regs->nip &= 0xffffffffUL; | ||
123 | return 1; | ||
124 | case 0x164: /* mtmsrd */ | ||
125 | /* only MSR_EE and MSR_RI get changed if bit 15 set */ | ||
126 | /* mtmsrd doesn't change MSR_HV and MSR_ME */ | ||
127 | imm = (instr & 0x10000)? 0x8002: 0xefffffffffffefffUL; | ||
128 | imm = (regs->msr & MSR_MASK & ~imm) | ||
129 | | (regs->gpr[rd] & imm); | ||
130 | if ((imm & MSR_RI) == 0) | ||
131 | /* can't step mtmsrd that would clear MSR_RI */ | ||
132 | return -1; | ||
133 | regs->msr = imm; | ||
134 | regs->nip += 4; | ||
135 | if ((imm & MSR_SF) == 0) | ||
136 | regs->nip &= 0xffffffffUL; | ||
137 | return 1; | ||
138 | } | ||
139 | } | ||
140 | return 0; | ||
141 | } | ||