]> git.proxmox.com Git - mirror_ubuntu-zesty-kernel.git/blob - arch/m68k/68360/entry.S
Merge branch 'ib-mfd-iio-3.19' of git://git.kernel.org/pub/scm/linux/kernel/git/lee...
[mirror_ubuntu-zesty-kernel.git] / arch / m68k / 68360 / entry.S
1 /*
2 * entry.S - non-mmu 68360 interrupt and exceptions entry points
3 *
4 * Copyright (C) 1991, 1992 Linus Torvalds
5 * Copyright (C) 2001 SED Systems, a Division of Calian Ltd.
6 *
7 * This file is subject to the terms and conditions of the GNU General Public
8 * License. See the file README.legal in the main directory of this archive
9 * for more details.
10 *
11 * Linux/m68k support by Hamish Macdonald
12 * M68360 Port by SED Systems, and Lineo.
13 */
14
15 #include <linux/linkage.h>
16 #include <asm/thread_info.h>
17 #include <asm/unistd.h>
18 #include <asm/errno.h>
19 #include <asm/setup.h>
20 #include <asm/segment.h>
21 #include <asm/traps.h>
22 #include <asm/asm-offsets.h>
23 #include <asm/entry.h>
24
25 .text
26
27 .globl system_call
28 .globl resume
29 .globl ret_from_exception
30 .globl ret_from_signal
31 .globl sys_call_table
32 .globl bad_interrupt
33 .globl inthandler
34
35 badsys:
36 movel #-ENOSYS,%sp@(PT_OFF_D0)
37 jra ret_from_exception
38
39 do_trace:
40 movel #-ENOSYS,%sp@(PT_OFF_D0) /* needed for strace*/
41 subql #4,%sp
42 SAVE_SWITCH_STACK
43 jbsr syscall_trace_enter
44 RESTORE_SWITCH_STACK
45 addql #4,%sp
46 movel %sp@(PT_OFF_ORIG_D0),%d1
47 movel #-ENOSYS,%d0
48 cmpl #NR_syscalls,%d1
49 jcc 1f
50 lsl #2,%d1
51 lea sys_call_table, %a0
52 jbsr %a0@(%d1)
53
54 1: movel %d0,%sp@(PT_OFF_D0) /* save the return value */
55 subql #4,%sp /* dummy return address */
56 SAVE_SWITCH_STACK
57 jbsr syscall_trace_leave
58
59 ret_from_signal:
60 RESTORE_SWITCH_STACK
61 addql #4,%sp
62 jra ret_from_exception
63
64 ENTRY(system_call)
65 SAVE_ALL_SYS
66
67 /* save top of frame*/
68 pea %sp@
69 jbsr set_esp0
70 addql #4,%sp
71
72 movel %sp@(PT_OFF_ORIG_D0),%d0
73
74 movel %sp,%d1 /* get thread_info pointer */
75 andl #-THREAD_SIZE,%d1
76 movel %d1,%a2
77 btst #(TIF_SYSCALL_TRACE%8),%a2@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
78 jne do_trace
79 cmpl #NR_syscalls,%d0
80 jcc badsys
81 lsl #2,%d0
82 lea sys_call_table,%a0
83 movel %a0@(%d0), %a0
84 jbsr %a0@
85 movel %d0,%sp@(PT_OFF_D0) /* save the return value*/
86
87 ret_from_exception:
88 btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel*/
89 jeq Luser_return /* if so, skip resched, signals*/
90
91 Lkernel_return:
92 RESTORE_ALL
93
94 Luser_return:
95 /* only allow interrupts when we are really the last one on the*/
96 /* kernel stack, otherwise stack overflow can occur during*/
97 /* heavy interrupt load*/
98 andw #ALLOWINT,%sr
99
100 movel %sp,%d1 /* get thread_info pointer */
101 andl #-THREAD_SIZE,%d1
102 movel %d1,%a2
103 1:
104 move %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
105 jne Lwork_to_do
106 RESTORE_ALL
107
108 Lwork_to_do:
109 movel %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
110 btst #TIF_NEED_RESCHED,%d1
111 jne reschedule
112
113 Lsignal_return:
114 subql #4,%sp /* dummy return address*/
115 SAVE_SWITCH_STACK
116 pea %sp@(SWITCH_STACK_SIZE)
117 bsrw do_notify_resume
118 addql #4,%sp
119 RESTORE_SWITCH_STACK
120 addql #4,%sp
121 jra 1b
122
123 /*
124 * This is the main interrupt handler, responsible for calling do_IRQ()
125 */
126 inthandler:
127 SAVE_ALL_INT
128 movew %sp@(PT_OFF_FORMATVEC), %d0
129 and.l #0x3ff, %d0
130 lsr.l #0x02, %d0
131
132 movel %sp,%sp@-
133 movel %d0,%sp@- /* put vector # on stack*/
134 jbsr do_IRQ /* process the IRQ */
135 addql #8,%sp /* pop parameters off stack*/
136 jra ret_from_exception
137
138 /*
139 * Handler for uninitialized and spurious interrupts.
140 */
141 bad_interrupt:
142 addql #1,irq_err_count
143 rte
144
145 /*
146 * Beware - when entering resume, prev (the current task) is
147 * in a0, next (the new task) is in a1, so don't change these
148 * registers until their contents are no longer needed.
149 */
150 ENTRY(resume)
151 movel %a0,%d1 /* save prev thread in d1 */
152 movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */
153 SAVE_SWITCH_STACK
154 movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */
155 movel %usp,%a3 /* save usp */
156 movel %a3,%a0@(TASK_THREAD+THREAD_USP)
157
158 movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore user stack */
159 movel %a3,%usp
160 movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */
161 RESTORE_SWITCH_STACK
162 movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */
163 rts
164