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
|
/*
* entry.S -- interrupt and exception processing for ColdFire
*
* Copyright (C) 1999-2007, Greg Ungerer (gerg@snapgear.com)
* Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
* Kenneth Albanowski <kjahds@kjahds.com>,
* Copyright (C) 2000 Lineo Inc. (www.lineo.com)
* Copyright (C) 2004-2006 Macq Electronique SA. (www.macqel.com)
*
* Based on:
*
* linux/arch/m68k/kernel/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
*
* 68060 fixes by Jesper Skov
* ColdFire support by Greg Ungerer (gerg@snapgear.com)
* 5307 fixes by David W. Miller
* linux 2.4 support David McCullough <davidm@snapgear.com>
* Bug, speed and maintainability fixes by Philippe De Muyter <phdm@macqel.be>
*/
#include <linux/linkage.h>
#include <asm/unistd.h>
#include <asm/thread_info.h>
#include <asm/errno.h>
#include <asm/setup.h>
#include <asm/asm-offsets.h>
#include <asm/entry.h>
#ifdef CONFIG_COLDFIRE_SW_A7
/*
* Define software copies of the supervisor and user stack pointers.
*/
.bss
sw_ksp:
.long 0
sw_usp:
.long 0
#endif /* CONFIG_COLDFIRE_SW_A7 */
.text
.globl system_call
.globl resume
.globl ret_from_exception
.globl sys_call_table
.globl inthandler
enosys:
mov.l #sys_ni_syscall,%d3
bra 1f
ENTRY(system_call)
SAVE_ALL_SYS
move #0x2000,%sr /* enable intrs again */
GET_CURRENT(%d2)
cmpl #NR_syscalls,%d0
jcc enosys
lea sys_call_table,%a0
lsll #2,%d0 /* movel %a0@(%d0:l:4),%d3 */
movel %a0@(%d0),%d3
jeq enosys
1:
movel %sp,%d2 /* get thread_info pointer */
andl #-THREAD_SIZE,%d2 /* at start of kernel stack */
movel %d2,%a0
movel %a0@,%a1 /* save top of frame */
movel %sp,%a1@(TASK_THREAD+THREAD_ESP0)
btst #(TIF_SYSCALL_TRACE%8),%a0@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
bnes 1f
movel %d3,%a0
jbsr %a0@
movel %d0,%sp@(PT_OFF_D0) /* save the return value */
jra ret_from_exception
1:
movel #-ENOSYS,%d2 /* strace needs -ENOSYS in PT_OFF_D0 */
movel %d2,PT_OFF_D0(%sp) /* on syscall entry */
subql #4,%sp
SAVE_SWITCH_STACK
jbsr syscall_trace_enter
RESTORE_SWITCH_STACK
addql #4,%sp
addql #1,%d0
jeq ret_from_exception
movel %d3,%a0
jbsr %a0@
movel %d0,%sp@(PT_OFF_D0) /* save the return value */
subql #4,%sp /* dummy return address */
SAVE_SWITCH_STACK
jbsr syscall_trace_leave
RESTORE_SWITCH_STACK
addql #4,%sp
ret_from_exception:
move #0x2700,%sr /* disable intrs */
btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel */
jeq Luser_return /* if so, skip resched, signals */
#ifdef CONFIG_PREEMPTION
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1 /* at base of kernel stack */
movel %d1,%a0
movel %a0@(TINFO_FLAGS),%d1 /* get thread_info->flags */
andl #(1<<TIF_NEED_RESCHED),%d1
jeq Lkernel_return
movel %a0@(TINFO_PREEMPT),%d1
cmpl #0,%d1
jne Lkernel_return
pea Lkernel_return
jmp preempt_schedule_irq /* preempt the kernel */
#endif
Lkernel_return:
moveml %sp@,%d1-%d5/%a0-%a2
lea %sp@(32),%sp /* space for 8 regs */
movel %sp@+,%d0
addql #4,%sp /* orig d0 */
addl %sp@+,%sp /* stk adj */
rte
Luser_return:
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1 /* at base of kernel stack */
movel %d1,%a0
moveb %a0@(TINFO_FLAGS+3),%d1 /* thread_info->flags (low 8 bits) */
jne Lwork_to_do /* still work to do */
Lreturn:
RESTORE_USER
Lwork_to_do:
movel %a0@(TINFO_FLAGS),%d1 /* get thread_info->flags */
move #0x2000,%sr /* enable intrs again */
btst #TIF_NEED_RESCHED,%d1
jne reschedule
Lsignal_return:
subql #4,%sp /* dummy return address */
SAVE_SWITCH_STACK
pea %sp@(SWITCH_STACK_SIZE)
jsr do_notify_resume
addql #4,%sp
RESTORE_SWITCH_STACK
addql #4,%sp
jmp Luser_return
/*
* This is the generic interrupt handler (for all hardware interrupt
* sources). Calls up to high level code to do all the work.
*/
ENTRY(inthandler)
SAVE_ALL_INT
GET_CURRENT(%d2)
movew %sp@(PT_OFF_FORMATVEC),%d0 /* put exception # in d0 */
andl #0x03fc,%d0 /* mask out vector only */
movel %sp,%sp@- /* push regs arg */
lsrl #2,%d0 /* calculate real vector # */
movel %d0,%sp@- /* push vector number */
jbsr do_IRQ /* call high level irq handler */
lea %sp@(8),%sp /* pop args off stack */
bra ret_from_exception
/*
* 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)
movew %sr,%d1 /* save current status */
movew %d1,%a0@(TASK_THREAD+THREAD_SR)
movel %a0,%d1 /* get prev thread in d1 */
SAVE_SWITCH_STACK
movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack pointer */
RDUSP /* movel %usp,%a3 */
movel %a3,%a0@(TASK_THREAD+THREAD_USP) /* save thread user stack */
#ifdef CONFIG_MMU
movel %a1,%a2 /* set new current */
#endif
movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore thread user stack */
WRUSP /* movel %a3,%usp */
movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new kernel stack */
movew %a1@(TASK_THREAD+THREAD_SR),%d7 /* restore new status */
movew %d7,%sr
RESTORE_SWITCH_STACK
rts
|
