3 * linux/arch/m68k/kernel/entry.S
5 * Copyright (C) 1991, 1992 Linus Torvalds
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
11 * Linux/m68k support by Hamish Macdonald
13 * 68060 fixes by Jesper Skov
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.
22 * NOTE: This code handles signal-recognition, which happens every time
23 * after a timer-interrupt and after each system call.
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.
32 * 6/05/00 RZ: addedd writeback completion after return from sighandler
36 #include <linux/config.h>
37 #include <linux/linkage.h>
38 #include <asm/entry.h>
39 #include <asm/errno.h>
40 #include <asm/setup.h>
41 #include <asm/segment.h>
42 #include <asm/traps.h>
43 #include <asm/unistd.h>
45 #include <asm/asm-offsets.h>
47 .globl system_call, buserr, trap, resume
49 .globl sys_fork, sys_clone, sys_vfork
50 .globl ret_from_interrupt, bad_interrupt
51 .globl auto_irqhandler_fixup
52 .globl user_irqvec_fixup, user_irqhandler_fixup
58 movel %sp,%sp@- | stack frame pointer argument
61 jra .Lret_from_exception
66 movel %sp,%sp@- | stack frame pointer argument
69 jra .Lret_from_exception
71 | After a fork we jump here directly from resume,
72 | so that %d1 contains the previous task
73 | schedule_tail now used regardless of CONFIG_SMP
78 jra .Lret_from_exception
81 movel #-ENOSYS,%sp@(PT_D0) | needed for strace
87 movel %sp@(PT_ORIG_D0),%d0
91 movel #-ENOSYS,%sp@(PT_D0)
100 jra .Lret_from_exception
102 ENTRY(ret_from_signal)
105 /* on 68040 complete pending writebacks if any */
107 bfextu %sp@(PT_VECTOR){#0,#4},%d0
108 subql #7,%d0 | bus error frame ?
115 jra .Lret_from_exception
122 movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
125 tstb %curptr@(TASK_INFO+TINFO_FLAGS+2)
127 cmpl #NR_syscalls,%d0
130 jbsr @(sys_call_table,%d0:l:4)@(0)
131 movel %d0,%sp@(PT_D0) | save the return value
134 movew %curptr@(TASK_INFO+TINFO_FLAGS+2),%d0
135 jne syscall_exit_work
139 btst #5,%sp@(PT_SR) | check if returning to kernel
140 bnes 1b | if so, skip resched, signals
150 ENTRY(ret_from_exception)
151 .Lret_from_exception:
152 btst #5,%sp@(PT_SR) | check if returning to kernel
153 bnes 1f | if so, skip resched, signals
154 | only allow interrupts when we are really the last one on the
155 | kernel stack, otherwise stack overflow can occur during
156 | heavy interrupt load
160 moveb %curptr@(TASK_INFO+TINFO_FLAGS+3),%d0
166 movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
175 subql #4,%sp | dummy return address
177 pea %sp@(SWITCH_STACK_SIZE)
183 jbra resume_userspace
186 bclr #7,%sp@(PT_SR) | clear trace bit in SR
193 jbra resume_userspace
196 /* This is the main interrupt handler for autovector interrupts */
198 ENTRY(auto_inthandler)
201 addqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
202 | put exception # in d0
203 bfextu %sp@(PT_VECTOR){#4,#10},%d0
207 movel %d0,%sp@- | put vector # on stack
208 #if defined(MACH_Q40_ONLY) && defined(CONFIG_BLK_DEV_FD)
209 btstb #4,0xff000000 | Q40 floppy needs very special treatment ...
217 auto_irqhandler_fixup = . + 2
218 jsr m68k_handle_int | process the IRQ
219 3: addql #8,%sp | pop parameters off stack
222 subqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
223 jeq ret_from_last_interrupt
227 ret_from_last_interrupt:
228 moveq #(~ALLOWINT>>8)&0xff,%d0
232 /* check if we need to do software interrupts */
233 tstl irq_stat+CPUSTAT_SOFTIRQ_PENDING
234 jeq .Lret_from_exception
235 pea ret_from_exception
238 /* Handler for user defined interrupt vectors */
240 ENTRY(user_inthandler)
243 addqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
244 | put exception # in d0
245 bfextu %sp@(PT_VECTOR){#4,#10},%d0
246 user_irqvec_fixup = . + 2
250 movel %d0,%sp@- | put vector # on stack
251 user_irqhandler_fixup = . + 2
252 jsr m68k_handle_int | process the IRQ
253 addql #8,%sp | pop parameters off stack
255 subqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
256 jeq ret_from_last_interrupt
259 /* Handler for uninitialized and spurious interrupts */
261 ENTRY(bad_inthandler)
264 addqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
270 subqb #1,%curptr@(TASK_INFO+TINFO_PREEMPT+1)
271 jeq ret_from_last_interrupt
277 pea %sp@(SWITCH_STACK_SIZE)
285 pea %sp@(SWITCH_STACK_SIZE)
293 pea %sp@(SWITCH_STACK_SIZE)
299 ENTRY(sys_sigsuspend)
301 pea %sp@(SWITCH_STACK_SIZE)
307 ENTRY(sys_rt_sigsuspend)
309 pea %sp@(SWITCH_STACK_SIZE)
310 jbsr do_rt_sigsuspend
321 ENTRY(sys_rt_sigreturn)
329 * Beware - when entering resume, prev (the current task) is
330 * in a0, next (the new task) is in a1,so don't change these
331 * registers until their contents are no longer needed.
335 movew %sr,%a0@(TASK_THREAD+THREAD_SR)
337 /* save fs (sfc,%dfc) (may be pointing to kernel memory) */
339 movew %d0,%a0@(TASK_THREAD+THREAD_FS)
342 /* it is better to use a movel here instead of a movew 8*) */
344 movel %d0,%a0@(TASK_THREAD+THREAD_USP)
346 /* save non-scratch registers on stack */
349 /* save current kernel stack pointer */
350 movel %sp,%a0@(TASK_THREAD+THREAD_KSP)
352 /* save floating point context */
353 #ifndef CONFIG_M68KFPU_EMU_ONLY
354 #ifdef CONFIG_M68KFPU_EMU
358 fsave %a0@(TASK_THREAD+THREAD_FPSTATE)
360 #if defined(CONFIG_M68060)
361 #if !defined(CPU_M68060_ONLY)
362 btst #3,m68k_cputype+3
365 /* The 060 FPU keeps status in bits 15-8 of the first longword */
366 tstb %a0@(TASK_THREAD+THREAD_FPSTATE+2)
368 #if !defined(CPU_M68060_ONLY)
371 #endif /* CONFIG_M68060 */
372 #if !defined(CPU_M68060_ONLY)
373 1: tstb %a0@(TASK_THREAD+THREAD_FPSTATE)
376 2: fmovemx %fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
377 fmoveml %fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
379 #endif /* CONFIG_M68KFPU_EMU_ONLY */
380 /* Return previous task in %d1 */
383 /* switch to new task (a1 contains new task) */
386 /* restore floating point context */
387 #ifndef CONFIG_M68KFPU_EMU_ONLY
388 #ifdef CONFIG_M68KFPU_EMU
392 #if defined(CONFIG_M68060)
393 #if !defined(CPU_M68060_ONLY)
394 btst #3,m68k_cputype+3
397 /* The 060 FPU keeps status in bits 15-8 of the first longword */
398 tstb %a1@(TASK_THREAD+THREAD_FPSTATE+2)
400 #if !defined(CPU_M68060_ONLY)
403 #endif /* CONFIG_M68060 */
404 #if !defined(CPU_M68060_ONLY)
405 1: tstb %a1@(TASK_THREAD+THREAD_FPSTATE)
408 2: fmovemx %a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
409 fmoveml %a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
410 3: frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
412 #endif /* CONFIG_M68KFPU_EMU_ONLY */
414 /* restore the kernel stack pointer */
415 movel %a1@(TASK_THREAD+THREAD_KSP),%sp
417 /* restore non-scratch registers */
420 /* restore user stack pointer */
421 movel %a1@(TASK_THREAD+THREAD_USP),%a0
424 /* restore fs (sfc,%dfc) */
425 movew %a1@(TASK_THREAD+THREAD_FS),%a0
429 /* restore status register */
430 movew %a1@(TASK_THREAD+THREAD_SR),%sr
437 .long sys_ni_syscall /* 0 - old "setup()" system call*/
442 .long sys_open /* 5 */
447 .long sys_unlink /* 10 */
452 .long sys_chmod /* 15 */
454 .long sys_ni_syscall /* old break syscall holder */
457 .long sys_getpid /* 20 */
462 .long sys_stime /* 25 */
467 .long sys_utime /* 30 */
468 .long sys_ni_syscall /* old stty syscall holder */
469 .long sys_ni_syscall /* old gtty syscall holder */
472 .long sys_ni_syscall /* 35 */ /* old ftime syscall holder */
477 .long sys_rmdir /* 40 */
481 .long sys_ni_syscall /* old prof syscall holder */
482 .long sys_brk /* 45 */
487 .long sys_getegid16 /* 50 */
489 .long sys_umount /* recycled never used phys() */
490 .long sys_ni_syscall /* old lock syscall holder */
492 .long sys_fcntl /* 55 */
493 .long sys_ni_syscall /* old mpx syscall holder */
495 .long sys_ni_syscall /* old ulimit syscall holder */
497 .long sys_umask /* 60 */
502 .long sys_getpgrp /* 65 */
507 .long sys_setreuid16 /* 70 */
511 .long sys_sethostname
512 .long sys_setrlimit /* 75 */
513 .long sys_old_getrlimit
515 .long sys_gettimeofday
516 .long sys_settimeofday
517 .long sys_getgroups16 /* 80 */
518 .long sys_setgroups16
522 .long sys_readlink /* 85 */
527 .long old_mmap /* 90 */
532 .long sys_fchown16 /* 95 */
533 .long sys_getpriority
534 .long sys_setpriority
535 .long sys_ni_syscall /* old profil syscall holder */
537 .long sys_fstatfs /* 100 */
538 .long sys_ni_syscall /* ioperm for i386 */
542 .long sys_getitimer /* 105 */
547 .long sys_ni_syscall /* 110 */ /* iopl for i386 */
549 .long sys_ni_syscall /* obsolete idle() syscall */
550 .long sys_ni_syscall /* vm86old for i386 */
552 .long sys_swapoff /* 115 */
557 .long sys_clone /* 120 */
558 .long sys_setdomainname
560 .long sys_cacheflush /* modify_ldt for i386 */
562 .long sys_mprotect /* 125 */
563 .long sys_sigprocmask
564 .long sys_ni_syscall /* old "create_module" */
565 .long sys_init_module
566 .long sys_delete_module
567 .long sys_ni_syscall /* 130 - old "get_kernel_syms" */
572 .long sys_sysfs /* 135 */
573 .long sys_personality
574 .long sys_ni_syscall /* for afs_syscall */
577 .long sys_llseek /* 140 */
582 .long sys_readv /* 145 */
587 .long sys_mlock /* 150 */
591 .long sys_sched_setparam
592 .long sys_sched_getparam /* 155 */
593 .long sys_sched_setscheduler
594 .long sys_sched_getscheduler
595 .long sys_sched_yield
596 .long sys_sched_get_priority_max
597 .long sys_sched_get_priority_min /* 160 */
598 .long sys_sched_rr_get_interval
601 .long sys_setresuid16
602 .long sys_getresuid16 /* 165 */
603 .long sys_getpagesize
604 .long sys_ni_syscall /* old sys_query_module */
607 .long sys_setresgid16 /* 170 */
608 .long sys_getresgid16
610 .long sys_rt_sigreturn
611 .long sys_rt_sigaction
612 .long sys_rt_sigprocmask /* 175 */
613 .long sys_rt_sigpending
614 .long sys_rt_sigtimedwait
615 .long sys_rt_sigqueueinfo
616 .long sys_rt_sigsuspend
617 .long sys_pread64 /* 180 */
622 .long sys_capset /* 185 */
623 .long sys_sigaltstack
625 .long sys_ni_syscall /* streams1 */
626 .long sys_ni_syscall /* streams2 */
627 .long sys_vfork /* 190 */
631 .long sys_ftruncate64
632 .long sys_stat64 /* 195 */
637 .long sys_getgid /* 200 */
642 .long sys_getgroups /* 205 */
647 .long sys_setresgid /* 210 */
652 .long sys_setfsuid /* 215 */
657 .long sys_getdents64 /* 220 */
662 .long sys_fsetxattr /* 225 */
667 .long sys_llistxattr /* 230 */
669 .long sys_removexattr
670 .long sys_lremovexattr
671 .long sys_fremovexattr
672 .long sys_futex /* 235 */
677 .long sys_readahead /* 240 */
680 .long sys_io_getevents
682 .long sys_io_cancel /* 245 */
685 .long sys_lookup_dcookie
686 .long sys_epoll_create
687 .long sys_epoll_ctl /* 250 */
689 .long sys_remap_file_pages
690 .long sys_set_tid_address
691 .long sys_timer_create
692 .long sys_timer_settime /* 255 */
693 .long sys_timer_gettime
694 .long sys_timer_getoverrun
695 .long sys_timer_delete
696 .long sys_clock_settime
697 .long sys_clock_gettime /* 260 */
698 .long sys_clock_getres
699 .long sys_clock_nanosleep
702 .long sys_tgkill /* 265 */
704 .long sys_fadvise64_64
706 .long sys_get_mempolicy
707 .long sys_set_mempolicy /* 270 */
710 .long sys_mq_timedsend
711 .long sys_mq_timedreceive
712 .long sys_mq_notify /* 275 */
713 .long sys_mq_getsetattr
715 .long sys_ni_syscall /* for sys_vserver */
717 .long sys_request_key /* 280 */