arch/m68k/kernel/entry.S - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0-or-later
  * -*- mode: asm -*-
  *
  *  linux/arch/m68k/kernel/entry.S
  *
  *  Copyright (C) 1991, 1992  Linus Torvalds
  *
  * Linux/m68k support by Hamish Macdonald
  *
  * 68060 fixes by Jesper Skov
  *
  */

 /*
  * entry.S  contains the system-call and fault low-level handling routines.
  * This also contains the timer-interrupt handler, as well as all interrupts
  * and faults that can result in a task-switch.
  *
  * NOTE: This code handles signal-recognition, which happens every time
  * after a timer-interrupt and after each system call.
  *
  */

 /*
  * 12/03/96 Jes: Currently we only support m68k single-cpu systems, so
  *               all pointers that used to be 'current' are now entry
  *               number 0 in the 'current_set' list.
  *
  *  6/05/00 RZ:	 addedd writeback completion after return from sighandler
  *		 for 68040
  */

 #include <linux/linkage.h>
 #include <asm/errno.h>
 #include <asm/setup.h>
 #include <asm/traps.h>
 #include <asm/unistd.h>
 #include <asm/asm-offsets.h>
 #include <asm/entry.h>

 .globl system_call, buserr, trap, resume
 .globl sys_call_table
 .globl __sys_fork, __sys_clone, __sys_vfork
 .globl bad_interrupt
 .globl auto_irqhandler_fixup
 .globl user_irqvec_fixup

 .text
 ENTRY(__sys_fork)
 	SAVE_SWITCH_STACK
 	jbsr	sys_fork
 	lea     %sp@(24),%sp
 	rts

 ENTRY(__sys_clone)
 	SAVE_SWITCH_STACK
 	pea	%sp@(SWITCH_STACK_SIZE)
 	jbsr	m68k_clone
 	lea     %sp@(28),%sp
 	rts

 ENTRY(__sys_vfork)
 	SAVE_SWITCH_STACK
 	jbsr	sys_vfork
 	lea     %sp@(24),%sp
 	rts

 ENTRY(__sys_clone3)
 	SAVE_SWITCH_STACK
 	pea	%sp@(SWITCH_STACK_SIZE)
 	jbsr	m68k_clone3
 	lea	%sp@(28),%sp
 	rts

 ENTRY(sys_sigreturn)
 	SAVE_SWITCH_STACK
 	movel	%sp,%a1			  	| switch_stack pointer
 	lea	%sp@(SWITCH_STACK_SIZE),%a0	| pt_regs pointer
 	lea     %sp@(-84),%sp			| leave a gap
 	movel	%a1,%sp@-
 	movel	%a0,%sp@-
 	jbsr	do_sigreturn
 	jra	1f				| shared with rt_sigreturn()

 ENTRY(sys_rt_sigreturn)
 	SAVE_SWITCH_STACK
 	movel	%sp,%a1			  	| switch_stack pointer
 	lea	%sp@(SWITCH_STACK_SIZE),%a0	| pt_regs pointer
 	lea     %sp@(-84),%sp			| leave a gap
 	movel	%a1,%sp@-
 	movel	%a0,%sp@-
 	| stack contents:
 	|   [original pt_regs address] [original switch_stack address]
 	|   [gap] [switch_stack] [pt_regs] [exception frame]
 	jbsr	do_rt_sigreturn

 1:
 	| stack contents now:
 	|   [original pt_regs address] [original switch_stack address]
 	|   [unused part of the gap] [moved switch_stack] [moved pt_regs]
 	|   [replacement exception frame]
 	| return value of do_{rt_,}sigreturn() points to moved switch_stack.

 	movel	%d0,%sp				| discard the leftover junk
 	RESTORE_SWITCH_STACK
 	| stack contents now is just [syscall return address] [pt_regs] [frame]
 	| return pt_regs.d0
 	movel	%sp@(PT_OFF_D0+4),%d0
 	rts

 ENTRY(buserr)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 	movel	%sp,%sp@-		| stack frame pointer argument
 	jbsr	buserr_c
 	addql	#4,%sp
 	jra	ret_from_exception

 ENTRY(trap)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 	movel	%sp,%sp@-		| stack frame pointer argument
 	jbsr	trap_c
 	addql	#4,%sp
 	jra	ret_from_exception

 	| After a fork we jump here directly from resume,
 	| so that %d1 contains the previous task
 	| schedule_tail now used regardless of CONFIG_SMP
 ENTRY(ret_from_fork)
 	movel	%d1,%sp@-
 	jsr	schedule_tail
 	addql	#4,%sp
 	jra	ret_from_exception

 ENTRY(ret_from_kernel_thread)
 	| a3 contains the kernel thread payload, d7 - its argument
 	movel	%d1,%sp@-
 	jsr	schedule_tail
 	movel	%d7,(%sp)
 	jsr	%a3@
 	addql	#4,%sp
 	jra	ret_from_exception

 #if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)

 #ifdef TRAP_DBG_INTERRUPT

 .globl dbginterrupt
 ENTRY(dbginterrupt)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 	movel	%sp,%sp@- 		/* stack frame pointer argument */
 	jsr	dbginterrupt_c
 	addql	#4,%sp
 	jra	ret_from_exception
 #endif

 ENTRY(reschedule)
 	/* save top of frame */
 	pea	%sp@
 	jbsr	set_esp0
 	addql	#4,%sp
 	pea	ret_from_exception
 	jmp	schedule

 ENTRY(ret_from_user_signal)
 	moveq #__NR_sigreturn,%d0
 	trap #0

 ENTRY(ret_from_user_rt_signal)
 	movel #__NR_rt_sigreturn,%d0
 	trap #0

 #else

 do_trace_entry:
 	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
 	addql	#1,%d0			| optimization for cmpil #-1,%d0
 	jeq	ret_from_syscall
 	movel	%sp@(PT_OFF_ORIG_D0),%d0
 	cmpl	#NR_syscalls,%d0
 	jcs	syscall
 	jra	ret_from_syscall
 badsys:
 	movel	#-ENOSYS,%sp@(PT_OFF_D0)
 	jra	ret_from_syscall

 do_trace_exit:
 	subql	#4,%sp
 	SAVE_SWITCH_STACK
 	jbsr	syscall_trace_leave
 	RESTORE_SWITCH_STACK
 	addql	#4,%sp
 	jra	.Lret_from_exception

 ENTRY(system_call)
 	SAVE_ALL_SYS

 	GET_CURRENT(%d1)
 	movel	%d1,%a1

 	| save top of frame
 	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)

 	| syscall trace?
 	tstb	%a1@(TINFO_FLAGS+2)
 	jmi	do_trace_entry
 	| seccomp filter active?
 	btst	#5,%a1@(TINFO_FLAGS+2)
 	bnes	do_trace_entry
 	cmpl	#NR_syscalls,%d0
 	jcc	badsys
 syscall:
 	jbsr	@(sys_call_table,%d0:l:4)@(0)
 	movel	%d0,%sp@(PT_OFF_D0)	| save the return value
 ret_from_syscall:
 	|oriw	#0x0700,%sr
 	movel	%curptr@(TASK_STACK),%a1
 	movew	%a1@(TINFO_FLAGS+2),%d0
 	jne	syscall_exit_work
 1:	RESTORE_ALL

 syscall_exit_work:
 	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
 	bnes	1b			| if so, skip resched, signals
 	lslw	#1,%d0
 	jcs	do_trace_exit
 	jmi	do_delayed_trace
 	lslw	#8,%d0
 	jne	do_signal_return
 	pea	resume_userspace
 	jra	schedule


 ENTRY(ret_from_exception)
 .Lret_from_exception:
 	btst	#5,%sp@(PT_OFF_SR)	| check if returning to kernel
 	bnes	1f			| if so, skip resched, signals
 	| 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

 resume_userspace:
 	movel	%curptr@(TASK_STACK),%a1
 	moveb	%a1@(TINFO_FLAGS+3),%d0
 	jne	exit_work
 1:	RESTORE_ALL

 exit_work:
 	| save top of frame
 	movel	%sp,%curptr@(TASK_THREAD+THREAD_ESP0)
 	lslb	#1,%d0
 	jne	do_signal_return
 	pea	resume_userspace
 	jra	schedule


 do_signal_return:
 	|andw	#ALLOWINT,%sr
 	subql	#4,%sp			| dummy return address
 	SAVE_SWITCH_STACK
 	pea	%sp@(SWITCH_STACK_SIZE)
 	bsrl	do_notify_resume
 	addql	#4,%sp
 	RESTORE_SWITCH_STACK
 	addql	#4,%sp
 	jbra	resume_userspace

 do_delayed_trace:
 	bclr	#7,%sp@(PT_OFF_SR)	| clear trace bit in SR
 	pea	1			| send SIGTRAP
 	movel	%curptr,%sp@-
 	pea	LSIGTRAP
 	jbsr	send_sig
 	addql	#8,%sp
 	addql	#4,%sp
 	jbra	resume_userspace


 /* This is the main interrupt handler for autovector interrupts */

 ENTRY(auto_inthandler)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 					|  put exception # in d0
 	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
 	subw	#VEC_SPUR,%d0

 	movel	%sp,%sp@-
 	movel	%d0,%sp@-		|  put vector # on stack
 auto_irqhandler_fixup = . + 2
 	jsr	do_IRQ			|  process the IRQ
 	addql	#8,%sp			|  pop parameters off stack
 	jra	ret_from_exception

 /* Handler for user defined interrupt vectors */

 ENTRY(user_inthandler)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)
 					|  put exception # in d0
 	bfextu	%sp@(PT_OFF_FORMATVEC){#4,#10},%d0
 user_irqvec_fixup = . + 2
 	subw	#VEC_USER,%d0

 	movel	%sp,%sp@-
 	movel	%d0,%sp@-		|  put vector # on stack
 	jsr	do_IRQ			|  process the IRQ
 	addql	#8,%sp			|  pop parameters off stack
 	jra	ret_from_exception

 /* Handler for uninitialized and spurious interrupts */

 ENTRY(bad_inthandler)
 	SAVE_ALL_INT
 	GET_CURRENT(%d0)

 	movel	%sp,%sp@-
 	jsr	handle_badint
 	addql	#4,%sp
 	jra	ret_from_exception

 resume:
 	/*
 	 * 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.
 	 */

 	/* save sr */
 	movew	%sr,%a0@(TASK_THREAD+THREAD_SR)

 	/* save fs (sfc,%dfc) (may be pointing to kernel memory) */
 	movec	%sfc,%d0
 	movew	%d0,%a0@(TASK_THREAD+THREAD_FC)

 	/* save usp */
 	/* it is better to use a movel here instead of a movew 8*) */
 	movec	%usp,%d0
 	movel	%d0,%a0@(TASK_THREAD+THREAD_USP)

 	/* save non-scratch registers on stack */
 	SAVE_SWITCH_STACK

 	/* save current kernel stack pointer */
 	movel	%sp,%a0@(TASK_THREAD+THREAD_KSP)

 	/* save floating point context */
 #ifndef CONFIG_M68KFPU_EMU_ONLY
 #ifdef CONFIG_M68KFPU_EMU
 	tstl	m68k_fputype
 	jeq	3f
 #endif
 	fsave	%a0@(TASK_THREAD+THREAD_FPSTATE)

 #if defined(CONFIG_M68060)
 #if !defined(CPU_M68060_ONLY)
 	btst	#3,m68k_cputype+3
 	beqs	1f
 #endif
 	/* The 060 FPU keeps status in bits 15-8 of the first longword */
 	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE+2)
 	jeq	3f
 #if !defined(CPU_M68060_ONLY)
 	jra	2f
 #endif
 #endif /* CONFIG_M68060 */
 #if !defined(CPU_M68060_ONLY)
 1:	tstb	%a0@(TASK_THREAD+THREAD_FPSTATE)
 	jeq	3f
 #endif
 2:	fmovemx	%fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
 	fmoveml	%fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
 3:
 #endif	/* CONFIG_M68KFPU_EMU_ONLY */
 	/* Return previous task in %d1 */
 	movel	%curptr,%d1

 	/* switch to new task (a1 contains new task) */
 	movel	%a1,%curptr

 	/* restore floating point context */
 #ifndef CONFIG_M68KFPU_EMU_ONLY
 #ifdef CONFIG_M68KFPU_EMU
 	tstl	m68k_fputype
 	jeq	4f
 #endif
 #if defined(CONFIG_M68060)
 #if !defined(CPU_M68060_ONLY)
 	btst	#3,m68k_cputype+3
 	beqs	1f
 #endif
 	/* The 060 FPU keeps status in bits 15-8 of the first longword */
 	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE+2)
 	jeq	3f
 #if !defined(CPU_M68060_ONLY)
 	jra	2f
 #endif
 #endif /* CONFIG_M68060 */
 #if !defined(CPU_M68060_ONLY)
 1:	tstb	%a1@(TASK_THREAD+THREAD_FPSTATE)
 	jeq	3f
 #endif
 2:	fmovemx	%a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
 	fmoveml	%a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
 3:	frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
 4:
 #endif	/* CONFIG_M68KFPU_EMU_ONLY */

 	/* restore the kernel stack pointer */
 	movel	%a1@(TASK_THREAD+THREAD_KSP),%sp

 	/* restore non-scratch registers */
 	RESTORE_SWITCH_STACK

 	/* restore user stack pointer */
 	movel	%a1@(TASK_THREAD+THREAD_USP),%a0
 	movel	%a0,%usp

 	/* restore fs (sfc,%dfc) */
 	movew	%a1@(TASK_THREAD+THREAD_FC),%a0
 	movec	%a0,%sfc
 	movec	%a0,%dfc

 	/* restore status register */
 	movew	%a1@(TASK_THREAD+THREAD_SR),%d0
 	oriw	#0x0700,%d0
 	movew	%d0,%sr

 	rts

 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
	/* SPDX-License-Identifier: GPL-2.0-or-later
	* -- mode: asm --
	*
	* linux/arch/m68k/kernel/entry.S
	*
	* Copyright (C) 1991, 1992 Linus Torvalds
	*
	* Linux/m68k support by Hamish Macdonald
	*
	* 68060 fixes by Jesper Skov
	*
	*/

	/*
	* entry.S contains the system-call and fault low-level handling routines.
	* This also contains the timer-interrupt handler, as well as all interrupts
	* and faults that can result in a task-switch.
	*
	* NOTE: This code handles signal-recognition, which happens every time
	* after a timer-interrupt and after each system call.
	*
	*/

	/*
	* 12/03/96 Jes: Currently we only support m68k single-cpu systems, so
	* all pointers that used to be 'current' are now entry
	* number 0 in the 'current_set' list.
	*
	* 6/05/00 RZ: addedd writeback completion after return from sighandler
	* for 68040
	*/

	#include <linux/linkage.h>
	#include <asm/errno.h>
	#include <asm/setup.h>
	#include <asm/traps.h>
	#include <asm/unistd.h>
	#include <asm/asm-offsets.h>
	#include <asm/entry.h>

	.globl system_call, buserr, trap, resume
	.globl sys_call_table
	.globl __sys_fork, __sys_clone, __sys_vfork
	.globl bad_interrupt
	.globl auto_irqhandler_fixup
	.globl user_irqvec_fixup

	.text
	ENTRY(__sys_fork)
	SAVE_SWITCH_STACK
	jbsr sys_fork
	lea %sp@(24),%sp
	rts

	ENTRY(__sys_clone)
	SAVE_SWITCH_STACK
	pea %sp@(SWITCH_STACK_SIZE)
	jbsr m68k_clone
	lea %sp@(28),%sp
	rts

	ENTRY(__sys_vfork)
	SAVE_SWITCH_STACK
	jbsr sys_vfork
	lea %sp@(24),%sp
	rts

	ENTRY(__sys_clone3)
	SAVE_SWITCH_STACK
	pea %sp@(SWITCH_STACK_SIZE)
	jbsr m68k_clone3
	lea %sp@(28),%sp
	rts

	ENTRY(sys_sigreturn)
	SAVE_SWITCH_STACK
	movel %sp,%a1 \| switch_stack pointer
	lea %sp@(SWITCH_STACK_SIZE),%a0 \| pt_regs pointer
	lea %sp@(-84),%sp \| leave a gap
	movel %a1,%sp@-
	movel %a0,%sp@-
	jbsr do_sigreturn
	jra 1f \| shared with rt_sigreturn()

	ENTRY(sys_rt_sigreturn)
	SAVE_SWITCH_STACK
	movel %sp,%a1 \| switch_stack pointer
	lea %sp@(SWITCH_STACK_SIZE),%a0 \| pt_regs pointer
	lea %sp@(-84),%sp \| leave a gap
	movel %a1,%sp@-
	movel %a0,%sp@-
	\| stack contents:
	\| [original pt_regs address] [original switch_stack address]
	\| [gap] [switch_stack] [pt_regs] [exception frame]
	jbsr do_rt_sigreturn

	1:
	\| stack contents now:
	\| [original pt_regs address] [original switch_stack address]
	\| [unused part of the gap] [moved switch_stack] [moved pt_regs]
	\| [replacement exception frame]
	\| return value of do_{rt_,}sigreturn() points to moved switch_stack.

	movel %d0,%sp \| discard the leftover junk
	RESTORE_SWITCH_STACK
	\| stack contents now is just [syscall return address] [pt_regs] [frame]
	\| return pt_regs.d0
	movel %sp@(PT_OFF_D0+4),%d0
	rts

	ENTRY(buserr)
	SAVE_ALL_INT
	GET_CURRENT(%d0)
	movel %sp,%sp@- \| stack frame pointer argument
	jbsr buserr_c
	addql #4,%sp
	jra ret_from_exception

	ENTRY(trap)
	SAVE_ALL_INT
	GET_CURRENT(%d0)
	movel %sp,%sp@- \| stack frame pointer argument
	jbsr trap_c
	addql #4,%sp
	jra ret_from_exception

	\| After a fork we jump here directly from resume,
	\| so that %d1 contains the previous task
	\| schedule_tail now used regardless of CONFIG_SMP
	ENTRY(ret_from_fork)
	movel %d1,%sp@-
	jsr schedule_tail
	addql #4,%sp
	jra ret_from_exception

	ENTRY(ret_from_kernel_thread)
	\| a3 contains the kernel thread payload, d7 - its argument
	movel %d1,%sp@-
	jsr schedule_tail
	movel %d7,(%sp)
	jsr %a3@
	addql #4,%sp
	jra ret_from_exception

	#if defined(CONFIG_COLDFIRE) \|\| !defined(CONFIG_MMU)

	#ifdef TRAP_DBG_INTERRUPT

	.globl dbginterrupt
	ENTRY(dbginterrupt)
	SAVE_ALL_INT
	GET_CURRENT(%d0)
	movel %sp,%sp@- /* stack frame pointer argument */
	jsr dbginterrupt_c
	addql #4,%sp
	jra ret_from_exception
	#endif

	ENTRY(reschedule)
	/* save top of frame */
	pea %sp@
	jbsr set_esp0
	addql #4,%sp
	pea ret_from_exception
	jmp schedule

	ENTRY(ret_from_user_signal)
	moveq #__NR_sigreturn,%d0
	trap #0

	ENTRY(ret_from_user_rt_signal)
	movel #__NR_rt_sigreturn,%d0
	trap #0

	#else

	do_trace_entry:
	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
	addql #1,%d0 \| optimization for cmpil #-1,%d0
	jeq ret_from_syscall
	movel %sp@(PT_OFF_ORIG_D0),%d0
	cmpl #NR_syscalls,%d0
	jcs syscall
	jra ret_from_syscall
	badsys:
	movel #-ENOSYS,%sp@(PT_OFF_D0)
	jra ret_from_syscall

	do_trace_exit:
	subql #4,%sp
	SAVE_SWITCH_STACK
	jbsr syscall_trace_leave
	RESTORE_SWITCH_STACK
	addql #4,%sp
	jra .Lret_from_exception

	ENTRY(system_call)
	SAVE_ALL_SYS

	GET_CURRENT(%d1)
	movel %d1,%a1

	\| save top of frame
	movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)

	\| syscall trace?
	tstb %a1@(TINFO_FLAGS+2)
	jmi do_trace_entry
	\| seccomp filter active?
	btst #5,%a1@(TINFO_FLAGS+2)
	bnes do_trace_entry
	cmpl #NR_syscalls,%d0
	jcc badsys
	syscall:
	jbsr @(sys_call_table,%d0:l:4)@(0)
	movel %d0,%sp@(PT_OFF_D0) \| save the return value
	ret_from_syscall:
	\|oriw #0x0700,%sr
	movel %curptr@(TASK_STACK),%a1
	movew %a1@(TINFO_FLAGS+2),%d0
	jne syscall_exit_work
	1: RESTORE_ALL

	syscall_exit_work:
	btst #5,%sp@(PT_OFF_SR) \| check if returning to kernel
	bnes 1b \| if so, skip resched, signals
	lslw #1,%d0
	jcs do_trace_exit
	jmi do_delayed_trace
	lslw #8,%d0
	jne do_signal_return
	pea resume_userspace
	jra schedule


	ENTRY(ret_from_exception)
	.Lret_from_exception:
	btst #5,%sp@(PT_OFF_SR) \| check if returning to kernel
	bnes 1f \| if so, skip resched, signals
	\| 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

	resume_userspace:
	movel %curptr@(TASK_STACK),%a1
	moveb %a1@(TINFO_FLAGS+3),%d0
	jne exit_work
	1: RESTORE_ALL

	exit_work:
	\| save top of frame
	movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
	lslb #1,%d0
	jne do_signal_return
	pea resume_userspace
	jra schedule


	do_signal_return:
	\|andw #ALLOWINT,%sr
	subql #4,%sp \| dummy return address
	SAVE_SWITCH_STACK
	pea %sp@(SWITCH_STACK_SIZE)
	bsrl do_notify_resume
	addql #4,%sp
	RESTORE_SWITCH_STACK
	addql #4,%sp
	jbra resume_userspace

	do_delayed_trace:
	bclr #7,%sp@(PT_OFF_SR) \| clear trace bit in SR
	pea 1 \| send SIGTRAP
	movel %curptr,%sp@-
	pea LSIGTRAP
	jbsr send_sig
	addql #8,%sp
	addql #4,%sp
	jbra resume_userspace


	/* This is the main interrupt handler for autovector interrupts */

	ENTRY(auto_inthandler)
	SAVE_ALL_INT
	GET_CURRENT(%d0)
	\| put exception # in d0
	bfextu %sp@(PT_OFF_FORMATVEC){#4,#10},%d0
	subw #VEC_SPUR,%d0

	movel %sp,%sp@-
	movel %d0,%sp@- \| put vector # on stack
	auto_irqhandler_fixup = . + 2
	jsr do_IRQ \| process the IRQ
	addql #8,%sp \| pop parameters off stack
	jra ret_from_exception

	/* Handler for user defined interrupt vectors */

	ENTRY(user_inthandler)
	SAVE_ALL_INT
	GET_CURRENT(%d0)
	\| put exception # in d0
	bfextu %sp@(PT_OFF_FORMATVEC){#4,#10},%d0
	user_irqvec_fixup = . + 2
	subw #VEC_USER,%d0

	movel %sp,%sp@-
	movel %d0,%sp@- \| put vector # on stack
	jsr do_IRQ \| process the IRQ
	addql #8,%sp \| pop parameters off stack
	jra ret_from_exception

	/* Handler for uninitialized and spurious interrupts */

	ENTRY(bad_inthandler)
	SAVE_ALL_INT
	GET_CURRENT(%d0)

	movel %sp,%sp@-
	jsr handle_badint
	addql #4,%sp
	jra ret_from_exception

	resume:
	/*
	* 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.
	*/

	/* save sr */
	movew %sr,%a0@(TASK_THREAD+THREAD_SR)

	/* save fs (sfc,%dfc) (may be pointing to kernel memory) */
	movec %sfc,%d0
	movew %d0,%a0@(TASK_THREAD+THREAD_FC)

	/* save usp */
	/* it is better to use a movel here instead of a movew 8) /
	movec %usp,%d0
	movel %d0,%a0@(TASK_THREAD+THREAD_USP)

	/* save non-scratch registers on stack */
	SAVE_SWITCH_STACK

	/* save current kernel stack pointer */
	movel %sp,%a0@(TASK_THREAD+THREAD_KSP)

	/* save floating point context */
	#ifndef CONFIG_M68KFPU_EMU_ONLY
	#ifdef CONFIG_M68KFPU_EMU
	tstl m68k_fputype
	jeq 3f
	#endif
	fsave %a0@(TASK_THREAD+THREAD_FPSTATE)

	#if defined(CONFIG_M68060)
	#if !defined(CPU_M68060_ONLY)
	btst #3,m68k_cputype+3
	beqs 1f
	#endif
	/* The 060 FPU keeps status in bits 15-8 of the first longword */
	tstb %a0@(TASK_THREAD+THREAD_FPSTATE+2)
	jeq 3f
	#if !defined(CPU_M68060_ONLY)
	jra 2f
	#endif
	#endif /* CONFIG_M68060 */
	#if !defined(CPU_M68060_ONLY)
	1: tstb %a0@(TASK_THREAD+THREAD_FPSTATE)
	jeq 3f
	#endif
	2: fmovemx %fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
	fmoveml %fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
	3:
	#endif /* CONFIG_M68KFPU_EMU_ONLY */
	/* Return previous task in %d1 */
	movel %curptr,%d1

	/* switch to new task (a1 contains new task) */
	movel %a1,%curptr

	/* restore floating point context */
	#ifndef CONFIG_M68KFPU_EMU_ONLY
	#ifdef CONFIG_M68KFPU_EMU
	tstl m68k_fputype
	jeq 4f
	#endif
	#if defined(CONFIG_M68060)
	#if !defined(CPU_M68060_ONLY)
	btst #3,m68k_cputype+3
	beqs 1f
	#endif
	/* The 060 FPU keeps status in bits 15-8 of the first longword */
	tstb %a1@(TASK_THREAD+THREAD_FPSTATE+2)
	jeq 3f
	#if !defined(CPU_M68060_ONLY)
	jra 2f
	#endif
	#endif /* CONFIG_M68060 */
	#if !defined(CPU_M68060_ONLY)
	1: tstb %a1@(TASK_THREAD+THREAD_FPSTATE)
	jeq 3f
	#endif
	2: fmovemx %a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
	fmoveml %a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
	3: frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
	4:
	#endif /* CONFIG_M68KFPU_EMU_ONLY */

	/* restore the kernel stack pointer */
	movel %a1@(TASK_THREAD+THREAD_KSP),%sp

	/* restore non-scratch registers */
	RESTORE_SWITCH_STACK

	/* restore user stack pointer */
	movel %a1@(TASK_THREAD+THREAD_USP),%a0
	movel %a0,%usp

	/* restore fs (sfc,%dfc) */
	movew %a1@(TASK_THREAD+THREAD_FC),%a0
	movec %a0,%sfc
	movec %a0,%dfc

	/* restore status register */
	movew %a1@(TASK_THREAD+THREAD_SR),%d0
	oriw #0x0700,%d0
	movew %d0,%sr

	rts

	#endif /* CONFIG_MMU && !CONFIG_COLDFIRE */