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
|
/*
* linux/arch/m68knommu/platform/68360/entry.S
*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 2001 SED Systems, a Division of Calian Ltd.
*
* 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
* M68360 Port by SED Systems, and Lineo.
*/
#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 inthandler
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@(TI_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@(TI_FLAGS),%d1 /* thread_info->flags */
jne Lwork_to_do
RESTORE_ALL
Lwork_to_do:
movel %a2@(TI_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 do_IRQ()
*/
inthandler:
SAVE_ALL
movew %sp@(PT_OFF_FORMATVEC), %d0
and.l #0x3ff, %d0
lsr.l #0x02, %d0
movel %sp,%sp@-
movel %d0,%sp@- /* put vector # on stack*/
jbsr do_IRQ /* 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 */
movel irq_stat+CPUSTAT_SOFTIRQ_PENDING,%d0
jeq ret_from_exception
pea ret_from_exception
jra do_softirq
/*
* Handler for uninitialized and spurious interrupts.
*/
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
|
