1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
|
/*
* linux/arch/m68knommu/platform/68328/entry.S
*
* Copyright (C) 1991, 1992 Linus Torvalds
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file README.legal in the main directory of this archive
* for more details.
*
* Linux/m68k support by Hamish Macdonald
*/
#include <linux/sys.h>
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
#include <asm/errno.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/traps.h>
#include <asm/asm-offsets.h>
#include <asm/entry.h>
.text
.globl system_call
.globl resume
.globl ret_from_exception
.globl ret_from_signal
.globl sys_call_table
.globl ret_from_interrupt
.globl bad_interrupt
.globl inthandler1
.globl inthandler2
.globl inthandler3
.globl inthandler4
.globl inthandler5
.globl inthandler6
.globl inthandler7
badsys:
movel #-ENOSYS,%sp@(PT_OFF_D0)
jra ret_from_exception
do_trace:
movel #-ENOSYS,%sp@(PT_OFF_D0) /* needed for strace*/
subql #4,%sp
SAVE_SWITCH_STACK
jbsr syscall_trace_enter
RESTORE_SWITCH_STACK
addql #4,%sp
movel %sp@(PT_OFF_ORIG_D0),%d1
movel #-ENOSYS,%d0
cmpl #NR_syscalls,%d1
jcc 1f
lsl #2,%d1
lea sys_call_table, %a0
jbsr %a0@(%d1)
1: movel %d0,%sp@(PT_OFF_D0) /* save the return value */
subql #4,%sp /* dummy return address */
SAVE_SWITCH_STACK
jbsr syscall_trace_leave
ret_from_signal:
RESTORE_SWITCH_STACK
addql #4,%sp
jra ret_from_exception
ENTRY(system_call)
SAVE_ALL
/* save top of frame*/
pea %sp@
jbsr set_esp0
addql #4,%sp
movel %sp@(PT_OFF_ORIG_D0),%d0
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1
movel %d1,%a2
btst #(TIF_SYSCALL_TRACE%8),%a2@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
jne do_trace
cmpl #NR_syscalls,%d0
jcc badsys
lsl #2,%d0
lea sys_call_table,%a0
movel %a0@(%d0), %a0
jbsr %a0@
movel %d0,%sp@(PT_OFF_D0) /* save the return value*/
ret_from_exception:
btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel*/
jeq Luser_return /* if so, skip resched, signals*/
Lkernel_return:
RESTORE_ALL
Luser_return:
/* only allow interrupts when we are really the last one on the*/
/* kernel stack, otherwise stack overflow can occur during*/
/* heavy interrupt load*/
andw #ALLOWINT,%sr
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1
movel %d1,%a2
1:
move %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
jne Lwork_to_do
RESTORE_ALL
Lwork_to_do:
movel %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
btst #TIF_NEED_RESCHED,%d1
jne reschedule
Lsignal_return:
subql #4,%sp /* dummy return address*/
SAVE_SWITCH_STACK
pea %sp@(SWITCH_STACK_SIZE)
bsrw do_signal
addql #4,%sp
RESTORE_SWITCH_STACK
addql #4,%sp
jra 1b
/*
* This is the main interrupt handler, responsible for calling process_int()
*/
inthandler1:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #65,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler2:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #66,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler3:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #67,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler4:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #68,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler5:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #69,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler6:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #70,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler7:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #71,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel %d0,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
ret_from_interrupt:
jeq 1f
2:
RESTORE_ALL
1:
moveb %sp@(PT_OFF_SR), %d0
and #7, %d0
jhi 2b
/* check if we need to do software interrupts */
jeq ret_from_exception
pea ret_from_exception
jra do_softirq
/*
* Handler for uninitialized and spurious interrupts.
*/
ENTRY(bad_interrupt)
addql #1,num_spurious
rte
/*
* Beware - when entering resume, prev (the current task) is
* in a0, next (the new task) is in a1,so don't change these
* registers until their contents are no longer needed.
*/
ENTRY(resume)
movel %a0,%d1 /* save prev thread in d1 */
movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */
movel %usp,%a2 /* save usp */
movel %a2,%a0@(TASK_THREAD+THREAD_USP)
SAVE_SWITCH_STACK
movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */
movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */
RESTORE_SWITCH_STACK
movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore user stack */
movel %a0,%usp
movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */
rts
|
