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v6.8
  1/* SPDX-License-Identifier: GPL-2.0-or-later
  2 * -*- mode: asm -*-
  3 *
  4 *  linux/arch/m68k/kernel/entry.S
  5 *
  6 *  Copyright (C) 1991, 1992  Linus Torvalds
  7 *
 
 
 
 
  8 * Linux/m68k support by Hamish Macdonald
  9 *
 10 * 68060 fixes by Jesper Skov
 11 *
 12 */
 13
 14/*
 15 * entry.S  contains the system-call and fault low-level handling routines.
 16 * This also contains the timer-interrupt handler, as well as all interrupts
 17 * and faults that can result in a task-switch.
 18 *
 19 * NOTE: This code handles signal-recognition, which happens every time
 20 * after a timer-interrupt and after each system call.
 21 *
 22 */
 23
 24/*
 25 * 12/03/96 Jes: Currently we only support m68k single-cpu systems, so
 26 *               all pointers that used to be 'current' are now entry
 27 *               number 0 in the 'current_set' list.
 28 *
 29 *  6/05/00 RZ:	 addedd writeback completion after return from sighandler
 30 *		 for 68040
 31 */
 32
 33#include <linux/linkage.h>
 34#include <asm/errno.h>
 35#include <asm/setup.h>
 
 36#include <asm/traps.h>
 37#include <asm/unistd.h>
 38#include <asm/asm-offsets.h>
 39#include <asm/entry.h>
 40
 41.globl system_call, buserr, trap, resume
 42.globl sys_call_table
 43.globl __sys_fork, __sys_clone, __sys_vfork
 44.globl bad_interrupt
 45.globl auto_irqhandler_fixup
 46.globl user_irqvec_fixup
 47
 48.text
 49ENTRY(__sys_fork)
 50	SAVE_SWITCH_STACK
 51	jbsr	sys_fork
 52	lea     %sp@(24),%sp
 53	rts
 54
 55ENTRY(__sys_clone)
 56	SAVE_SWITCH_STACK
 57	pea	%sp@(SWITCH_STACK_SIZE)
 58	jbsr	m68k_clone
 59	lea     %sp@(28),%sp
 60	rts
 61
 62ENTRY(__sys_vfork)
 63	SAVE_SWITCH_STACK
 64	jbsr	sys_vfork
 65	lea     %sp@(24),%sp
 66	rts
 67
 68ENTRY(__sys_clone3)
 69	SAVE_SWITCH_STACK
 70	pea	%sp@(SWITCH_STACK_SIZE)
 71	jbsr	m68k_clone3
 72	lea	%sp@(28),%sp
 73	rts
 74
 75ENTRY(sys_sigreturn)
 76	SAVE_SWITCH_STACK
 77	movel	%sp,%a1			  	| switch_stack pointer
 78	lea	%sp@(SWITCH_STACK_SIZE),%a0	| pt_regs pointer
 79	lea     %sp@(-84),%sp			| leave a gap
 80	movel	%a1,%sp@-
 81	movel	%a0,%sp@-
 82	jbsr	do_sigreturn
 83	jra	1f				| shared with rt_sigreturn()
 
 
 84
 85ENTRY(sys_rt_sigreturn)
 86	SAVE_SWITCH_STACK
 87	movel	%sp,%a1			  	| switch_stack pointer
 88	lea	%sp@(SWITCH_STACK_SIZE),%a0	| pt_regs pointer
 89	lea     %sp@(-84),%sp			| leave a gap
 90	movel	%a1,%sp@-
 91	movel	%a0,%sp@-
 92	| stack contents:
 93	|   [original pt_regs address] [original switch_stack address]
 94	|   [gap] [switch_stack] [pt_regs] [exception frame]
 95	jbsr	do_rt_sigreturn
 96
 971:
 98	| stack contents now:
 99	|   [original pt_regs address] [original switch_stack address]
100	|   [unused part of the gap] [moved switch_stack] [moved pt_regs]
101	|   [replacement exception frame]
102	| return value of do_{rt_,}sigreturn() points to moved switch_stack.
103
104	movel	%d0,%sp				| discard the leftover junk
105	RESTORE_SWITCH_STACK
106	| stack contents now is just [syscall return address] [pt_regs] [frame]
107	| return pt_regs.d0
108	movel	%sp@(PT_OFF_D0+4),%d0
109	rts
110
111ENTRY(buserr)
112	SAVE_ALL_INT
113	GET_CURRENT(%d0)
114	movel	%sp,%sp@-		| stack frame pointer argument
115	jbsr	buserr_c
116	addql	#4,%sp
117	jra	ret_from_exception
118
119ENTRY(trap)
120	SAVE_ALL_INT
121	GET_CURRENT(%d0)
122	movel	%sp,%sp@-		| stack frame pointer argument
123	jbsr	trap_c
124	addql	#4,%sp
125	jra	ret_from_exception
126
127	| After a fork we jump here directly from resume,
128	| so that %d1 contains the previous task
129	| schedule_tail now used regardless of CONFIG_SMP
130ENTRY(ret_from_fork)
131	movel	%d1,%sp@-
132	jsr	schedule_tail
133	addql	#4,%sp
134	jra	ret_from_exception
135
136ENTRY(ret_from_kernel_thread)
137	| a3 contains the kernel thread payload, d7 - its argument
138	movel	%d1,%sp@-
139	jsr	schedule_tail
140	movel	%d7,(%sp)
141	jsr	%a3@
142	addql	#4,%sp
143	jra	ret_from_exception
144
145#if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
146
147#ifdef TRAP_DBG_INTERRUPT
148
149.globl dbginterrupt
150ENTRY(dbginterrupt)
151	SAVE_ALL_INT
152	GET_CURRENT(%d0)
153	movel	%sp,%sp@- 		/* stack frame pointer argument */
154	jsr	dbginterrupt_c
155	addql	#4,%sp
156	jra	ret_from_exception
157#endif
158
159ENTRY(reschedule)
160	/* save top of frame */
161	pea	%sp@
162	jbsr	set_esp0
163	addql	#4,%sp
164	pea	ret_from_exception
165	jmp	schedule
166
167ENTRY(ret_from_user_signal)
168	moveq #__NR_sigreturn,%d0
169	trap #0
170
171ENTRY(ret_from_user_rt_signal)
172	movel #__NR_rt_sigreturn,%d0
173	trap #0
174
175#else
176
177do_trace_entry:
178	movel	#-ENOSYS,%sp@(PT_OFF_D0)| needed for strace
179	subql	#4,%sp
180	SAVE_SWITCH_STACK
181	jbsr	syscall_trace_enter
182	RESTORE_SWITCH_STACK
183	addql	#4,%sp
184	addql	#1,%d0			| optimization for cmpil #-1,%d0
185	jeq	ret_from_syscall
186	movel	%sp@(PT_OFF_ORIG_D0),%d0
187	cmpl	#NR_syscalls,%d0
188	jcs	syscall
189	jra	ret_from_syscall
190badsys:
191	movel	#-ENOSYS,%sp@(PT_OFF_D0)
192	jra	ret_from_syscall
193
194do_trace_exit:
195	subql	#4,%sp
196	SAVE_SWITCH_STACK
197	jbsr	syscall_trace_leave
198	RESTORE_SWITCH_STACK
199	addql	#4,%sp
200	jra	.Lret_from_exception
201
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
202ENTRY(system_call)
203	SAVE_ALL_SYS
204
205	GET_CURRENT(%d1)
206	movel	%d1,%a1
207
208	| save top of frame
209	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
210
211	| syscall trace?
212	tstb	%a1@(TINFO_FLAGS+2)
213	jmi	do_trace_entry
214	| seccomp filter active?
215	btst	#5,%a1@(TINFO_FLAGS+2)
216	bnes	do_trace_entry
217	cmpl	#NR_syscalls,%d0
218	jcc	badsys
219syscall:
220	jbsr	@(sys_call_table,%d0:l:4)@(0)
221	movel	%d0,%sp@(PT_OFF_D0)	| save the return value
222ret_from_syscall:
223	|oriw	#0x0700,%sr
224	movel	%curptr@(TASK_STACK),%a1
225	movew	%a1@(TINFO_FLAGS+2),%d0
226	jne	syscall_exit_work
2271:	RESTORE_ALL
228
229syscall_exit_work:
230	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
231	bnes	1b			| if so, skip resched, signals
232	lslw	#1,%d0
233	jcs	do_trace_exit
234	jmi	do_delayed_trace
235	lslw	#8,%d0
236	jne	do_signal_return
237	pea	resume_userspace
238	jra	schedule
239
240
241ENTRY(ret_from_exception)
242.Lret_from_exception:
243	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
244	bnes	1f			| if so, skip resched, signals
245	| only allow interrupts when we are really the last one on the
246	| kernel stack, otherwise stack overflow can occur during
247	| heavy interrupt load
248	andw	#ALLOWINT,%sr
249
250resume_userspace:
251	movel	%curptr@(TASK_STACK),%a1
252	moveb	%a1@(TINFO_FLAGS+3),%d0
253	jne	exit_work
2541:	RESTORE_ALL
255
256exit_work:
257	| save top of frame
258	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
259	lslb	#1,%d0
260	jne	do_signal_return
261	pea	resume_userspace
262	jra	schedule
263
264
265do_signal_return:
266	|andw	#ALLOWINT,%sr
267	subql	#4,%sp			| dummy return address
268	SAVE_SWITCH_STACK
269	pea	%sp@(SWITCH_STACK_SIZE)
270	bsrl	do_notify_resume
271	addql	#4,%sp
272	RESTORE_SWITCH_STACK
273	addql	#4,%sp
274	jbra	resume_userspace
275
276do_delayed_trace:
277	bclr	#7,%sp@(PT_OFF_SR)	| clear trace bit in SR
278	pea	1			| send SIGTRAP
279	movel	%curptr,%sp@-
280	pea	LSIGTRAP
281	jbsr	send_sig
282	addql	#8,%sp
283	addql	#4,%sp
284	jbra	resume_userspace
285
286
287/* This is the main interrupt handler for autovector interrupts */
288
289ENTRY(auto_inthandler)
290	SAVE_ALL_INT
291	GET_CURRENT(%d0)
292					|  put exception # in d0
293	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
294	subw	#VEC_SPUR,%d0
295
296	movel	%sp,%sp@-
297	movel	%d0,%sp@-		|  put vector # on stack
298auto_irqhandler_fixup = . + 2
299	jsr	do_IRQ			|  process the IRQ
300	addql	#8,%sp			|  pop parameters off stack
301	jra	ret_from_exception
302
303/* Handler for user defined interrupt vectors */
304
305ENTRY(user_inthandler)
306	SAVE_ALL_INT
307	GET_CURRENT(%d0)
308					|  put exception # in d0
309	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
310user_irqvec_fixup = . + 2
311	subw	#VEC_USER,%d0
312
313	movel	%sp,%sp@-
314	movel	%d0,%sp@-		|  put vector # on stack
315	jsr	do_IRQ			|  process the IRQ
316	addql	#8,%sp			|  pop parameters off stack
317	jra	ret_from_exception
318
319/* Handler for uninitialized and spurious interrupts */
320
321ENTRY(bad_inthandler)
322	SAVE_ALL_INT
323	GET_CURRENT(%d0)
324
325	movel	%sp,%sp@-
326	jsr	handle_badint
327	addql	#4,%sp
328	jra	ret_from_exception
329
330resume:
331	/*
332	 * Beware - when entering resume, prev (the current task) is
333	 * in a0, next (the new task) is in a1,so don't change these
334	 * registers until their contents are no longer needed.
335	 */
336
337	/* save sr */
338	movew	%sr,%a0@(TASK_THREAD+THREAD_SR)
339
340	/* save fs (sfc,%dfc) (may be pointing to kernel memory) */
341	movec	%sfc,%d0
342	movew	%d0,%a0@(TASK_THREAD+THREAD_FC)
343
344	/* save usp */
345	/* it is better to use a movel here instead of a movew 8*) */
346	movec	%usp,%d0
347	movel	%d0,%a0@(TASK_THREAD+THREAD_USP)
348
349	/* save non-scratch registers on stack */
350	SAVE_SWITCH_STACK
351
352	/* save current kernel stack pointer */
353	movel	%sp,%a0@(TASK_THREAD+THREAD_KSP)
354
355	/* save floating point context */
356#ifndef CONFIG_M68KFPU_EMU_ONLY
357#ifdef CONFIG_M68KFPU_EMU
358	tstl	m68k_fputype
359	jeq	3f
360#endif
361	fsave	%a0@(TASK_THREAD+THREAD_FPSTATE)
362
363#if defined(CONFIG_M68060)
364#if !defined(CPU_M68060_ONLY)
365	btst	#3,m68k_cputype+3
366	beqs	1f
367#endif
368	/* The 060 FPU keeps status in bits 15-8 of the first longword */
369	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE+2)
370	jeq	3f
371#if !defined(CPU_M68060_ONLY)
372	jra	2f
373#endif
374#endif /* CONFIG_M68060 */
375#if !defined(CPU_M68060_ONLY)
3761:	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE)
377	jeq	3f
378#endif
3792:	fmovemx	%fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
380	fmoveml	%fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
3813:
382#endif	/* CONFIG_M68KFPU_EMU_ONLY */
383	/* Return previous task in %d1 */
384	movel	%curptr,%d1
385
386	/* switch to new task (a1 contains new task) */
387	movel	%a1,%curptr
388
389	/* restore floating point context */
390#ifndef CONFIG_M68KFPU_EMU_ONLY
391#ifdef CONFIG_M68KFPU_EMU
392	tstl	m68k_fputype
393	jeq	4f
394#endif
395#if defined(CONFIG_M68060)
396#if !defined(CPU_M68060_ONLY)
397	btst	#3,m68k_cputype+3
398	beqs	1f
399#endif
400	/* The 060 FPU keeps status in bits 15-8 of the first longword */
401	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE+2)
402	jeq	3f
403#if !defined(CPU_M68060_ONLY)
404	jra	2f
405#endif
406#endif /* CONFIG_M68060 */
407#if !defined(CPU_M68060_ONLY)
4081:	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE)
409	jeq	3f
410#endif
4112:	fmovemx	%a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
412	fmoveml	%a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
4133:	frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
4144:
415#endif	/* CONFIG_M68KFPU_EMU_ONLY */
416
417	/* restore the kernel stack pointer */
418	movel	%a1@(TASK_THREAD+THREAD_KSP),%sp
419
420	/* restore non-scratch registers */
421	RESTORE_SWITCH_STACK
422
423	/* restore user stack pointer */
424	movel	%a1@(TASK_THREAD+THREAD_USP),%a0
425	movel	%a0,%usp
426
427	/* restore fs (sfc,%dfc) */
428	movew	%a1@(TASK_THREAD+THREAD_FC),%a0
429	movec	%a0,%sfc
430	movec	%a0,%dfc
431
432	/* restore status register */
433	movew	%a1@(TASK_THREAD+THREAD_SR),%sr
434
435	rts
436
437#endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
v4.6
  1/* -*- mode: asm -*-
 
  2 *
  3 *  linux/arch/m68k/kernel/entry.S
  4 *
  5 *  Copyright (C) 1991, 1992  Linus Torvalds
  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 *
 13 * 68060 fixes by Jesper Skov
 14 *
 15 */
 16
 17/*
 18 * entry.S  contains the system-call and fault low-level handling routines.
 19 * This also contains the timer-interrupt handler, as well as all interrupts
 20 * and faults that can result in a task-switch.
 21 *
 22 * NOTE: This code handles signal-recognition, which happens every time
 23 * after a timer-interrupt and after each system call.
 24 *
 25 */
 26
 27/*
 28 * 12/03/96 Jes: Currently we only support m68k single-cpu systems, so
 29 *               all pointers that used to be 'current' are now entry
 30 *               number 0 in the 'current_set' list.
 31 *
 32 *  6/05/00 RZ:	 addedd writeback completion after return from sighandler
 33 *		 for 68040
 34 */
 35
 36#include <linux/linkage.h>
 37#include <asm/errno.h>
 38#include <asm/setup.h>
 39#include <asm/segment.h>
 40#include <asm/traps.h>
 41#include <asm/unistd.h>
 42#include <asm/asm-offsets.h>
 43#include <asm/entry.h>
 44
 45.globl system_call, buserr, trap, resume
 46.globl sys_call_table
 47.globl __sys_fork, __sys_clone, __sys_vfork
 48.globl bad_interrupt
 49.globl auto_irqhandler_fixup
 50.globl user_irqvec_fixup
 51
 52.text
 53ENTRY(__sys_fork)
 54	SAVE_SWITCH_STACK
 55	jbsr	sys_fork
 56	lea     %sp@(24),%sp
 57	rts
 58
 59ENTRY(__sys_clone)
 60	SAVE_SWITCH_STACK
 61	pea	%sp@(SWITCH_STACK_SIZE)
 62	jbsr	m68k_clone
 63	lea     %sp@(28),%sp
 64	rts
 65
 66ENTRY(__sys_vfork)
 67	SAVE_SWITCH_STACK
 68	jbsr	sys_vfork
 69	lea     %sp@(24),%sp
 70	rts
 71
 
 
 
 
 
 
 
 72ENTRY(sys_sigreturn)
 73	SAVE_SWITCH_STACK
 74	movel	%sp,%sp@-		  | switch_stack pointer
 75	pea	%sp@(SWITCH_STACK_SIZE+4) | pt_regs pointer
 
 
 
 76	jbsr	do_sigreturn
 77	addql	#8,%sp
 78	RESTORE_SWITCH_STACK
 79	rts
 80
 81ENTRY(sys_rt_sigreturn)
 82	SAVE_SWITCH_STACK
 83	movel	%sp,%sp@-		  | switch_stack pointer
 84	pea	%sp@(SWITCH_STACK_SIZE+4) | pt_regs pointer
 
 
 
 
 
 
 85	jbsr	do_rt_sigreturn
 86	addql	#8,%sp
 
 
 
 
 
 
 
 
 87	RESTORE_SWITCH_STACK
 
 
 
 88	rts
 89
 90ENTRY(buserr)
 91	SAVE_ALL_INT
 92	GET_CURRENT(%d0)
 93	movel	%sp,%sp@-		| stack frame pointer argument
 94	jbsr	buserr_c
 95	addql	#4,%sp
 96	jra	ret_from_exception
 97
 98ENTRY(trap)
 99	SAVE_ALL_INT
100	GET_CURRENT(%d0)
101	movel	%sp,%sp@-		| stack frame pointer argument
102	jbsr	trap_c
103	addql	#4,%sp
104	jra	ret_from_exception
105
106	| After a fork we jump here directly from resume,
107	| so that %d1 contains the previous task
108	| schedule_tail now used regardless of CONFIG_SMP
109ENTRY(ret_from_fork)
110	movel	%d1,%sp@-
111	jsr	schedule_tail
112	addql	#4,%sp
113	jra	ret_from_exception
114
115ENTRY(ret_from_kernel_thread)
116	| a3 contains the kernel thread payload, d7 - its argument
117	movel	%d1,%sp@-
118	jsr	schedule_tail
119	movel	%d7,(%sp)
120	jsr	%a3@
121	addql	#4,%sp
122	jra	ret_from_exception
123
124#if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
125
126#ifdef TRAP_DBG_INTERRUPT
127
128.globl dbginterrupt
129ENTRY(dbginterrupt)
130	SAVE_ALL_INT
131	GET_CURRENT(%d0)
132	movel	%sp,%sp@- 		/* stack frame pointer argument */
133	jsr	dbginterrupt_c
134	addql	#4,%sp
135	jra	ret_from_exception
136#endif
137
138ENTRY(reschedule)
139	/* save top of frame */
140	pea	%sp@
141	jbsr	set_esp0
142	addql	#4,%sp
143	pea	ret_from_exception
144	jmp	schedule
145
146ENTRY(ret_from_user_signal)
147	moveq #__NR_sigreturn,%d0
148	trap #0
149
150ENTRY(ret_from_user_rt_signal)
151	movel #__NR_rt_sigreturn,%d0
152	trap #0
153
154#else
155
156do_trace_entry:
157	movel	#-ENOSYS,%sp@(PT_OFF_D0)| needed for strace
158	subql	#4,%sp
159	SAVE_SWITCH_STACK
160	jbsr	syscall_trace
161	RESTORE_SWITCH_STACK
162	addql	#4,%sp
 
 
163	movel	%sp@(PT_OFF_ORIG_D0),%d0
164	cmpl	#NR_syscalls,%d0
165	jcs	syscall
 
166badsys:
167	movel	#-ENOSYS,%sp@(PT_OFF_D0)
168	jra	ret_from_syscall
169
170do_trace_exit:
171	subql	#4,%sp
172	SAVE_SWITCH_STACK
173	jbsr	syscall_trace
174	RESTORE_SWITCH_STACK
175	addql	#4,%sp
176	jra	.Lret_from_exception
177
178ENTRY(ret_from_signal)
179	movel	%curptr@(TASK_STACK),%a1
180	tstb	%a1@(TINFO_FLAGS+2)
181	jge	1f
182	jbsr	syscall_trace
1831:	RESTORE_SWITCH_STACK
184	addql	#4,%sp
185/* on 68040 complete pending writebacks if any */
186#ifdef CONFIG_M68040
187	bfextu	%sp@(PT_OFF_FORMATVEC){#0,#4},%d0
188	subql	#7,%d0				| bus error frame ?
189	jbne	1f
190	movel	%sp,%sp@-
191	jbsr	berr_040cleanup
192	addql	#4,%sp
1931:
194#endif
195	jra	.Lret_from_exception
196
197ENTRY(system_call)
198	SAVE_ALL_SYS
199
200	GET_CURRENT(%d1)
201	movel	%d1,%a1
202
203	| save top of frame
204	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
205
206	| syscall trace?
207	tstb	%a1@(TINFO_FLAGS+2)
208	jmi	do_trace_entry
 
 
 
209	cmpl	#NR_syscalls,%d0
210	jcc	badsys
211syscall:
212	jbsr	@(sys_call_table,%d0:l:4)@(0)
213	movel	%d0,%sp@(PT_OFF_D0)	| save the return value
214ret_from_syscall:
215	|oriw	#0x0700,%sr
216	movel	%curptr@(TASK_STACK),%a1
217	movew	%a1@(TINFO_FLAGS+2),%d0
218	jne	syscall_exit_work
2191:	RESTORE_ALL
220
221syscall_exit_work:
222	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
223	bnes	1b			| if so, skip resched, signals
224	lslw	#1,%d0
225	jcs	do_trace_exit
226	jmi	do_delayed_trace
227	lslw	#8,%d0
228	jne	do_signal_return
229	pea	resume_userspace
230	jra	schedule
231
232
233ENTRY(ret_from_exception)
234.Lret_from_exception:
235	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
236	bnes	1f			| if so, skip resched, signals
237	| only allow interrupts when we are really the last one on the
238	| kernel stack, otherwise stack overflow can occur during
239	| heavy interrupt load
240	andw	#ALLOWINT,%sr
241
242resume_userspace:
243	movel	%curptr@(TASK_STACK),%a1
244	moveb	%a1@(TINFO_FLAGS+3),%d0
245	jne	exit_work
2461:	RESTORE_ALL
247
248exit_work:
249	| save top of frame
250	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
251	lslb	#1,%d0
252	jne	do_signal_return
253	pea	resume_userspace
254	jra	schedule
255
256
257do_signal_return:
258	|andw	#ALLOWINT,%sr
259	subql	#4,%sp			| dummy return address
260	SAVE_SWITCH_STACK
261	pea	%sp@(SWITCH_STACK_SIZE)
262	bsrl	do_notify_resume
263	addql	#4,%sp
264	RESTORE_SWITCH_STACK
265	addql	#4,%sp
266	jbra	resume_userspace
267
268do_delayed_trace:
269	bclr	#7,%sp@(PT_OFF_SR)	| clear trace bit in SR
270	pea	1			| send SIGTRAP
271	movel	%curptr,%sp@-
272	pea	LSIGTRAP
273	jbsr	send_sig
274	addql	#8,%sp
275	addql	#4,%sp
276	jbra	resume_userspace
277
278
279/* This is the main interrupt handler for autovector interrupts */
280
281ENTRY(auto_inthandler)
282	SAVE_ALL_INT
283	GET_CURRENT(%d0)
284					|  put exception # in d0
285	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
286	subw	#VEC_SPUR,%d0
287
288	movel	%sp,%sp@-
289	movel	%d0,%sp@-		|  put vector # on stack
290auto_irqhandler_fixup = . + 2
291	jsr	do_IRQ			|  process the IRQ
292	addql	#8,%sp			|  pop parameters off stack
293	jra	ret_from_exception
294
295/* Handler for user defined interrupt vectors */
296
297ENTRY(user_inthandler)
298	SAVE_ALL_INT
299	GET_CURRENT(%d0)
300					|  put exception # in d0
301	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
302user_irqvec_fixup = . + 2
303	subw	#VEC_USER,%d0
304
305	movel	%sp,%sp@-
306	movel	%d0,%sp@-		|  put vector # on stack
307	jsr	do_IRQ			|  process the IRQ
308	addql	#8,%sp			|  pop parameters off stack
309	jra	ret_from_exception
310
311/* Handler for uninitialized and spurious interrupts */
312
313ENTRY(bad_inthandler)
314	SAVE_ALL_INT
315	GET_CURRENT(%d0)
316
317	movel	%sp,%sp@-
318	jsr	handle_badint
319	addql	#4,%sp
320	jra	ret_from_exception
321
322resume:
323	/*
324	 * Beware - when entering resume, prev (the current task) is
325	 * in a0, next (the new task) is in a1,so don't change these
326	 * registers until their contents are no longer needed.
327	 */
328
329	/* save sr */
330	movew	%sr,%a0@(TASK_THREAD+THREAD_SR)
331
332	/* save fs (sfc,%dfc) (may be pointing to kernel memory) */
333	movec	%sfc,%d0
334	movew	%d0,%a0@(TASK_THREAD+THREAD_FS)
335
336	/* save usp */
337	/* it is better to use a movel here instead of a movew 8*) */
338	movec	%usp,%d0
339	movel	%d0,%a0@(TASK_THREAD+THREAD_USP)
340
341	/* save non-scratch registers on stack */
342	SAVE_SWITCH_STACK
343
344	/* save current kernel stack pointer */
345	movel	%sp,%a0@(TASK_THREAD+THREAD_KSP)
346
347	/* save floating point context */
348#ifndef CONFIG_M68KFPU_EMU_ONLY
349#ifdef CONFIG_M68KFPU_EMU
350	tstl	m68k_fputype
351	jeq	3f
352#endif
353	fsave	%a0@(TASK_THREAD+THREAD_FPSTATE)
354
355#if defined(CONFIG_M68060)
356#if !defined(CPU_M68060_ONLY)
357	btst	#3,m68k_cputype+3
358	beqs	1f
359#endif
360	/* The 060 FPU keeps status in bits 15-8 of the first longword */
361	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE+2)
362	jeq	3f
363#if !defined(CPU_M68060_ONLY)
364	jra	2f
365#endif
366#endif /* CONFIG_M68060 */
367#if !defined(CPU_M68060_ONLY)
3681:	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE)
369	jeq	3f
370#endif
3712:	fmovemx	%fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
372	fmoveml	%fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
3733:
374#endif	/* CONFIG_M68KFPU_EMU_ONLY */
375	/* Return previous task in %d1 */
376	movel	%curptr,%d1
377
378	/* switch to new task (a1 contains new task) */
379	movel	%a1,%curptr
380
381	/* restore floating point context */
382#ifndef CONFIG_M68KFPU_EMU_ONLY
383#ifdef CONFIG_M68KFPU_EMU
384	tstl	m68k_fputype
385	jeq	4f
386#endif
387#if defined(CONFIG_M68060)
388#if !defined(CPU_M68060_ONLY)
389	btst	#3,m68k_cputype+3
390	beqs	1f
391#endif
392	/* The 060 FPU keeps status in bits 15-8 of the first longword */
393	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE+2)
394	jeq	3f
395#if !defined(CPU_M68060_ONLY)
396	jra	2f
397#endif
398#endif /* CONFIG_M68060 */
399#if !defined(CPU_M68060_ONLY)
4001:	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE)
401	jeq	3f
402#endif
4032:	fmovemx	%a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
404	fmoveml	%a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
4053:	frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
4064:
407#endif	/* CONFIG_M68KFPU_EMU_ONLY */
408
409	/* restore the kernel stack pointer */
410	movel	%a1@(TASK_THREAD+THREAD_KSP),%sp
411
412	/* restore non-scratch registers */
413	RESTORE_SWITCH_STACK
414
415	/* restore user stack pointer */
416	movel	%a1@(TASK_THREAD+THREAD_USP),%a0
417	movel	%a0,%usp
418
419	/* restore fs (sfc,%dfc) */
420	movew	%a1@(TASK_THREAD+THREAD_FS),%a0
421	movec	%a0,%sfc
422	movec	%a0,%dfc
423
424	/* restore status register */
425	movew	%a1@(TASK_THREAD+THREAD_SR),%sr
426
427	rts
428
429#endif /* CONFIG_MMU && !CONFIG_COLDFIRE */