| /* |
| * linux/arch/m68knommu/platform/5307/entry.S |
| * |
| * Copyright (C) 1999-2007, Greg Ungerer (gerg@snapgear.com) |
| * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>, |
| * Kenneth Albanowski <kjahds@kjahds.com>, |
| * Copyright (C) 2000 Lineo Inc. (www.lineo.com) |
| * Copyright (C) 2004-2006 Macq Electronique SA. (www.macqel.com) |
| * |
| * Based on: |
| * |
| * linux/arch/m68k/kernel/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 |
| * |
| * 68060 fixes by Jesper Skov |
| * ColdFire support by Greg Ungerer (gerg@snapgear.com) |
| * 5307 fixes by David W. Miller |
| * linux 2.4 support David McCullough <davidm@snapgear.com> |
| * Bug, speed and maintainability fixes by Philippe De Muyter <phdm@macqel.be> |
| */ |
| |
| #include <linux/sys.h> |
| #include <linux/linkage.h> |
| #include <asm/unistd.h> |
| #include <asm/thread_info.h> |
| #include <asm/errno.h> |
| #include <asm/setup.h> |
| #include <asm/segment.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/entry.h> |
| |
| .bss |
| |
| sw_ksp: |
| .long 0 |
| |
| sw_usp: |
| .long 0 |
| |
| .text |
| |
| .globl system_call |
| .globl resume |
| .globl ret_from_exception |
| .globl ret_from_signal |
| .globl sys_call_table |
| .globl ret_from_interrupt |
| .globl inthandler |
| .globl fasthandler |
| |
| enosys: |
| mov.l #sys_ni_syscall,%d3 |
| bra 1f |
| |
| ENTRY(system_call) |
| SAVE_ALL |
| move #0x2000,%sr /* enable intrs again */ |
| |
| cmpl #NR_syscalls,%d0 |
| jcc enosys |
| lea sys_call_table,%a0 |
| lsll #2,%d0 /* movel %a0@(%d0:l:4),%d3 */ |
| movel %a0@(%d0),%d3 |
| jeq enosys |
| |
| 1: |
| movel %sp,%d2 /* get thread_info pointer */ |
| andl #-THREAD_SIZE,%d2 /* at start of kernel stack */ |
| movel %d2,%a0 |
| movel %a0@,%a1 /* save top of frame */ |
| movel %sp,%a1@(TASK_THREAD+THREAD_ESP0) |
| btst #(TIF_SYSCALL_TRACE%8),%a0@(TI_FLAGS+(31-TIF_SYSCALL_TRACE)/8) |
| bnes 1f |
| |
| movel %d3,%a0 |
| jbsr %a0@ |
| movel %d0,%sp@(PT_OFF_D0) /* save the return value */ |
| jra ret_from_exception |
| 1: |
| movel #-ENOSYS,%d2 /* strace needs -ENOSYS in PT_OFF_D0 */ |
| movel %d2,PT_OFF_D0(%sp) /* on syscall entry */ |
| subql #4,%sp |
| SAVE_SWITCH_STACK |
| jbsr syscall_trace_enter |
| RESTORE_SWITCH_STACK |
| addql #4,%sp |
| movel %d3,%a0 |
| jbsr %a0@ |
| 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 |
| |
| ret_from_exception: |
| move #0x2700,%sr /* disable intrs */ |
| btst #5,%sp@(PT_OFF_SR) /* check if returning to kernel */ |
| jeq Luser_return /* if so, skip resched, signals */ |
| |
| #ifdef CONFIG_PREEMPT |
| movel %sp,%d1 /* get thread_info pointer */ |
| andl #-THREAD_SIZE,%d1 /* at base of kernel stack */ |
| movel %d1,%a0 |
| movel %a0@(TI_FLAGS),%d1 /* get thread_info->flags */ |
| andl #(1<<TIF_NEED_RESCHED),%d1 |
| jeq Lkernel_return |
| |
| movel %a0@(TI_PREEMPTCOUNT),%d1 |
| cmpl #0,%d1 |
| jne Lkernel_return |
| |
| pea Lkernel_return |
| jmp preempt_schedule_irq /* preempt the kernel */ |
| #endif |
| |
| Lkernel_return: |
| moveml %sp@,%d1-%d5/%a0-%a2 |
| lea %sp@(32),%sp /* space for 8 regs */ |
| movel %sp@+,%d0 |
| addql #4,%sp /* orig d0 */ |
| addl %sp@+,%sp /* stk adj */ |
| rte |
| |
| Luser_return: |
| movel %sp,%d1 /* get thread_info pointer */ |
| andl #-THREAD_SIZE,%d1 /* at base of kernel stack */ |
| movel %d1,%a0 |
| movel %a0@(TI_FLAGS),%d1 /* get thread_info->flags */ |
| andl #0xefff,%d1 |
| jne Lwork_to_do /* still work to do */ |
| |
| Lreturn: |
| move #0x2700,%sr /* disable intrs */ |
| movel sw_usp,%a0 /* get usp */ |
| movel %sp@(PT_OFF_PC),%a0@- /* copy exception program counter */ |
| movel %sp@(PT_OFF_FORMATVEC),%a0@- /* copy exception format/vector/sr */ |
| moveml %sp@,%d1-%d5/%a0-%a2 |
| lea %sp@(32),%sp /* space for 8 regs */ |
| movel %sp@+,%d0 |
| addql #4,%sp /* orig d0 */ |
| addl %sp@+,%sp /* stk adj */ |
| addql #8,%sp /* remove exception */ |
| movel %sp,sw_ksp /* save ksp */ |
| subql #8,sw_usp /* set exception */ |
| movel sw_usp,%sp /* restore usp */ |
| rte |
| |
| Lwork_to_do: |
| movel %a0@(TI_FLAGS),%d1 /* get thread_info->flags */ |
| move #0x2000,%sr /* enable intrs again */ |
| btst #TIF_NEED_RESCHED,%d1 |
| jne reschedule |
| |
| /* GERG: do we need something here for TRACEing?? */ |
| |
| Lsignal_return: |
| subql #4,%sp /* dummy return address */ |
| SAVE_SWITCH_STACK |
| pea %sp@(SWITCH_STACK_SIZE) |
| jsr do_signal |
| addql #4,%sp |
| RESTORE_SWITCH_STACK |
| addql #4,%sp |
| jmp Luser_return |
| |
| /* |
| * This is the generic interrupt handler (for all hardware interrupt |
| * sources). Calls upto high level code to do all the work. |
| */ |
| ENTRY(inthandler) |
| SAVE_ALL |
| moveq #-1,%d0 |
| movel %d0,%sp@(PT_OFF_ORIG_D0) |
| |
| movew %sp@(PT_OFF_FORMATVEC),%d0 /* put exception # in d0 */ |
| andl #0x03fc,%d0 /* mask out vector only */ |
| |
| movel %sp,%sp@- /* push regs arg */ |
| lsrl #2,%d0 /* calculate real vector # */ |
| movel %d0,%sp@- /* push vector number */ |
| jbsr do_IRQ /* call high level irq handler */ |
| lea %sp@(8),%sp /* pop args off stack */ |
| |
| bra ret_from_interrupt /* this was fallthrough */ |
| |
| /* |
| * This is the fast interrupt handler (for certain hardware interrupt |
| * sources). Unlike the normal interrupt handler it just uses the |
| * current stack (doesn't care if it is user or kernel). It also |
| * doesn't bother doing the bottom half handlers. |
| */ |
| ENTRY(fasthandler) |
| SAVE_LOCAL |
| |
| movew %sp@(PT_OFF_FORMATVEC),%d0 |
| andl #0x03fc,%d0 /* mask out vector only */ |
| |
| movel %sp,%sp@- /* push regs arg */ |
| lsrl #2,%d0 /* calculate real vector # */ |
| movel %d0,%sp@- /* push vector number */ |
| jbsr do_IRQ /* call high level irq handler */ |
| lea %sp@(8),%sp /* pop args off stack */ |
| |
| RESTORE_LOCAL |
| |
| ENTRY(ret_from_interrupt) |
| /* the fasthandler is confusing me, haven't seen any user */ |
| jmp ret_from_exception |
| |
| /* |
| * 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. |
| * This is always called in supervisor mode, so don't bother to save |
| * and restore sr; user's process sr is actually in the stack. |
| */ |
| ENTRY(resume) |
| movel %a0, %d1 /* get prev thread in d1 */ |
| |
| movel sw_usp,%d0 /* save usp */ |
| movel %d0,%a0@(TASK_THREAD+THREAD_USP) |
| |
| SAVE_SWITCH_STACK |
| movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack pointer */ |
| movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */ |
| RESTORE_SWITCH_STACK |
| |
| movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */ |
| movel %a0, sw_usp |
| rts |