linux/arch/m68k/platform/68328/entry.S
Greg Ungerer 61619b1207 m68k: merge mmu and non-mmu include/asm/entry.h files
The changes in the mmu version of entry.h (entry_mm.h) and the non-mmu
version (entry_no.h) are not about the presence or use of an MMU at all.
The main changes are to support the ColdFire processors. The code for
trap entry and exit for all types of 68k processor outside coldfire is
the same.

So merge the files back to a single entry.h and share the common 68k
entry/exit code. Some changes are required for the non-mmu entry
handlers to adopt the differing macros for system call and interrupt
entry, but this is quite strait forward. The changes for the ColdFire
remove a couple of instructions for the separate a7 register case, and
are no worse for the older single a7 register case.

Signed-off-by: Greg Ungerer <gerg@uclinux.org>
2011-10-18 14:22:25 +10:00

262 lines
5.8 KiB
ArmAsm

/*
* linux/arch/m68knommu/platform/68328/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
*/
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <asm/unistd.h>
#include <asm/errno.h>
#include <asm/setup.h>
#include <asm/segment.h>
#include <asm/traps.h>
#include <asm/asm-offsets.h>
#include <asm/entry.h>
.text
.globl system_call
.globl resume
.globl ret_from_exception
.globl ret_from_signal
.globl sys_call_table
.globl ret_from_interrupt
.globl bad_interrupt
.globl inthandler1
.globl inthandler2
.globl inthandler3
.globl inthandler4
.globl inthandler5
.globl inthandler6
.globl inthandler7
badsys:
movel #-ENOSYS,%sp@(PT_OFF_D0)
jra ret_from_exception
do_trace:
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
movel %sp@(PT_OFF_ORIG_D0),%d1
movel #-ENOSYS,%d0
cmpl #NR_syscalls,%d1
jcc 1f
lsl #2,%d1
lea sys_call_table, %a0
jbsr %a0@(%d1)
1: movel %d0,%sp@(PT_OFF_D0) /* save the return value */
subql #4,%sp /* dummy return address */
SAVE_SWITCH_STACK
jbsr syscall_trace_leave
ret_from_signal:
RESTORE_SWITCH_STACK
addql #4,%sp
jra ret_from_exception
ENTRY(system_call)
SAVE_ALL_SYS
/* save top of frame*/
pea %sp@
jbsr set_esp0
addql #4,%sp
movel %sp@(PT_OFF_ORIG_D0),%d0
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1
movel %d1,%a2
btst #(TIF_SYSCALL_TRACE%8),%a2@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
jne do_trace
cmpl #NR_syscalls,%d0
jcc badsys
lsl #2,%d0
lea sys_call_table,%a0
movel %a0@(%d0), %a0
jbsr %a0@
movel %d0,%sp@(PT_OFF_D0) /* save the return value*/
ret_from_exception:
btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel*/
jeq Luser_return /* if so, skip resched, signals*/
Lkernel_return:
RESTORE_ALL
Luser_return:
/* 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
movel %sp,%d1 /* get thread_info pointer */
andl #-THREAD_SIZE,%d1
movel %d1,%a2
1:
move %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
jne Lwork_to_do
RESTORE_ALL
Lwork_to_do:
movel %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
btst #TIF_NEED_RESCHED,%d1
jne reschedule
Lsignal_return:
subql #4,%sp /* dummy return address*/
SAVE_SWITCH_STACK
pea %sp@(SWITCH_STACK_SIZE)
bsrw do_signal
addql #4,%sp
RESTORE_SWITCH_STACK
addql #4,%sp
jra 1b
/*
* This is the main interrupt handler, responsible for calling process_int()
*/
inthandler1:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #65,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler2:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #66,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler3:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #67,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler4:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #68,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler5:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #69,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler6:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #70,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler7:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel #71,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
inthandler:
SAVE_ALL_INT
movew %sp@(PT_OFF_FORMATVEC), %d0
and #0x3ff, %d0
movel %sp,%sp@-
movel %d0,%sp@- /* put vector # on stack*/
jbsr process_int /* process the IRQ*/
3: addql #8,%sp /* pop parameters off stack*/
bra ret_from_interrupt
ret_from_interrupt:
jeq 1f
2:
RESTORE_ALL
1:
moveb %sp@(PT_OFF_SR), %d0
and #7, %d0
jhi 2b
/* check if we need to do software interrupts */
jeq ret_from_exception
pea ret_from_exception
jra do_softirq
/*
* Handler for uninitialized and spurious interrupts.
*/
ENTRY(bad_interrupt)
addql #1,irq_err_count
rte
/*
* 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)
movel %a0,%d1 /* save prev thread in d1 */
movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */
SAVE_SWITCH_STACK
movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */
movel %usp,%a3 /* save usp */
movel %a3,%a0@(TASK_THREAD+THREAD_USP)
movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore user stack */
movel %a3,%usp
movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */
RESTORE_SWITCH_STACK
movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */
rts