forked from Minki/linux
61619b1207
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>
183 lines
4.0 KiB
ArmAsm
183 lines
4.0 KiB
ArmAsm
/*
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* linux/arch/m68knommu/platform/68360/entry.S
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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* Copyright (C) 2001 SED Systems, a Division of Calian Ltd.
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file README.legal in the main directory of this archive
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* for more details.
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*
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* Linux/m68k support by Hamish Macdonald
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* M68360 Port by SED Systems, and Lineo.
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*/
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#include <linux/linkage.h>
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#include <asm/thread_info.h>
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#include <asm/unistd.h>
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#include <asm/errno.h>
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#include <asm/setup.h>
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#include <asm/segment.h>
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#include <asm/traps.h>
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#include <asm/asm-offsets.h>
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#include <asm/entry.h>
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.text
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.globl system_call
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.globl resume
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.globl ret_from_exception
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.globl ret_from_signal
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.globl sys_call_table
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.globl ret_from_interrupt
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.globl bad_interrupt
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.globl inthandler
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badsys:
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movel #-ENOSYS,%sp@(PT_OFF_D0)
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jra ret_from_exception
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do_trace:
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movel #-ENOSYS,%sp@(PT_OFF_D0) /* needed for strace*/
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subql #4,%sp
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SAVE_SWITCH_STACK
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jbsr syscall_trace_enter
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RESTORE_SWITCH_STACK
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addql #4,%sp
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movel %sp@(PT_OFF_ORIG_D0),%d1
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movel #-ENOSYS,%d0
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cmpl #NR_syscalls,%d1
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jcc 1f
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lsl #2,%d1
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lea sys_call_table, %a0
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jbsr %a0@(%d1)
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1: movel %d0,%sp@(PT_OFF_D0) /* save the return value */
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subql #4,%sp /* dummy return address */
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SAVE_SWITCH_STACK
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jbsr syscall_trace_leave
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ret_from_signal:
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RESTORE_SWITCH_STACK
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addql #4,%sp
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jra ret_from_exception
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ENTRY(system_call)
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SAVE_ALL_SYS
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/* save top of frame*/
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pea %sp@
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jbsr set_esp0
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addql #4,%sp
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movel %sp@(PT_OFF_ORIG_D0),%d0
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movel %sp,%d1 /* get thread_info pointer */
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andl #-THREAD_SIZE,%d1
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movel %d1,%a2
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btst #(TIF_SYSCALL_TRACE%8),%a2@(TINFO_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
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jne do_trace
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cmpl #NR_syscalls,%d0
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jcc badsys
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lsl #2,%d0
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lea sys_call_table,%a0
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movel %a0@(%d0), %a0
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jbsr %a0@
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movel %d0,%sp@(PT_OFF_D0) /* save the return value*/
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ret_from_exception:
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btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel*/
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jeq Luser_return /* if so, skip resched, signals*/
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Lkernel_return:
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RESTORE_ALL
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Luser_return:
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/* only allow interrupts when we are really the last one on the*/
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/* kernel stack, otherwise stack overflow can occur during*/
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/* heavy interrupt load*/
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andw #ALLOWINT,%sr
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movel %sp,%d1 /* get thread_info pointer */
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andl #-THREAD_SIZE,%d1
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movel %d1,%a2
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1:
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move %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
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jne Lwork_to_do
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RESTORE_ALL
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Lwork_to_do:
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movel %a2@(TINFO_FLAGS),%d1 /* thread_info->flags */
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btst #TIF_NEED_RESCHED,%d1
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jne reschedule
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Lsignal_return:
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subql #4,%sp /* dummy return address*/
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SAVE_SWITCH_STACK
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pea %sp@(SWITCH_STACK_SIZE)
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bsrw do_signal
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addql #4,%sp
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RESTORE_SWITCH_STACK
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addql #4,%sp
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jra 1b
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/*
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* This is the main interrupt handler, responsible for calling do_IRQ()
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*/
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inthandler:
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SAVE_ALL_INT
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movew %sp@(PT_OFF_FORMATVEC), %d0
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and.l #0x3ff, %d0
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lsr.l #0x02, %d0
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movel %sp,%sp@-
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movel %d0,%sp@- /* put vector # on stack*/
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jbsr do_IRQ /* process the IRQ*/
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3: addql #8,%sp /* pop parameters off stack*/
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bra ret_from_interrupt
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ret_from_interrupt:
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jeq 1f
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2:
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RESTORE_ALL
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1:
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moveb %sp@(PT_OFF_SR), %d0
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and #7, %d0
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jhi 2b
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/* check if we need to do software interrupts */
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movel irq_stat+CPUSTAT_SOFTIRQ_PENDING,%d0
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jeq ret_from_exception
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pea ret_from_exception
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jra do_softirq
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/*
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* Handler for uninitialized and spurious interrupts.
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*/
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bad_interrupt:
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addql #1,irq_err_count
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rte
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/*
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* Beware - when entering resume, prev (the current task) is
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* in a0, next (the new task) is in a1, so don't change these
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* registers until their contents are no longer needed.
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*/
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ENTRY(resume)
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movel %a0,%d1 /* save prev thread in d1 */
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movew %sr,%a0@(TASK_THREAD+THREAD_SR) /* save sr */
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SAVE_SWITCH_STACK
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movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack */
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movel %usp,%a3 /* save usp */
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movel %a3,%a0@(TASK_THREAD+THREAD_USP)
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movel %a1@(TASK_THREAD+THREAD_USP),%a3 /* restore user stack */
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movel %a3,%usp
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movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */
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RESTORE_SWITCH_STACK
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movew %a1@(TASK_THREAD+THREAD_SR),%sr /* restore thread status reg */
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rts
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