2 * linux/arch/m68knommu/platform/5307/entry.S
4 * Copyright (C) 1999-2002, Greg Ungerer (gerg@snapgear.com)
5 * Copyright (C) 1998 D. Jeff Dionne <jeff@lineo.ca>,
6 * Kenneth Albanowski <kjahds@kjahds.com>,
7 * Copyright (C) 2000 Lineo Inc. (www.lineo.com)
8 * Copyright (C) 2004-2006 Macq Electronique SA. (www.macqel.com)
12 * linux/arch/m68k/kernel/entry.S
14 * Copyright (C) 1991, 1992 Linus Torvalds
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file README.legal in the main directory of this archive
20 * Linux/m68k support by Hamish Macdonald
22 * 68060 fixes by Jesper Skov
23 * ColdFire support by Greg Ungerer (gerg@snapgear.com)
24 * 5307 fixes by David W. Miller
25 * linux 2.4 support David McCullough <davidm@snapgear.com>
26 * Bug, speed and maintainability fixes by Philippe De Muyter <phdm@macqel.be>
29 #include <linux/config.h>
30 #include <linux/sys.h>
31 #include <linux/linkage.h>
32 #include <asm/unistd.h>
33 #include <asm/thread_info.h>
34 #include <asm/errno.h>
35 #include <asm/setup.h>
36 #include <asm/segment.h>
37 #include <asm/asm-offsets.h>
38 #include <asm/entry.h>
52 .globl ret_from_exception
53 .globl ret_from_signal
55 .globl ret_from_interrupt
60 mov.l #sys_ni_syscall,%d3
65 move #0x2000,%sr /* enable intrs again */
69 lea sys_call_table,%a0
70 lsll #2,%d0 /* movel %a0@(%d0:l:4),%d3 */
75 movel %sp,%d2 /* get thread_info pointer */
76 andl #-THREAD_SIZE,%d2 /* at start of kernel stack */
78 movel %sp,%a0@(THREAD_ESP0) /* save top of frame */
79 btst #(TIF_SYSCALL_TRACE%8),%a0@(TI_FLAGS+(31-TIF_SYSCALL_TRACE)/8)
84 movel %d0,%sp@(PT_D0) /* save the return value */
85 jra ret_from_exception
94 movel %d0,%sp@(PT_D0) /* save the return value */
95 subql #4,%sp /* dummy return address */
104 btst #5,%sp@(PT_SR) /* check if returning to kernel */
105 jeq Luser_return /* if so, skip resched, signals */
108 moveml %sp@,%d1-%d5/%a0-%a2
109 lea %sp@(32),%sp /* space for 8 regs */
111 addql #4,%sp /* orig d0 */
112 addl %sp@+,%sp /* stk adj */
116 movel %sp,%d1 /* get thread_info pointer */
117 andl #-THREAD_SIZE,%d1 /* at base of kernel stack */
119 movel %a0@(TI_FLAGS),%d1 /* get thread_info->flags */
120 andl #_TIF_WORK_MASK,%d1
121 jne Lwork_to_do /* still work to do */
124 move #0x2700,%sr /* disable intrs */
125 movel sw_usp,%a0 /* get usp */
126 movel %sp@(PT_PC),%a0@- /* copy exception program counter */
127 movel %sp@(PT_FORMATVEC),%a0@-/* copy exception format/vector/sr */
128 moveml %sp@,%d1-%d5/%a0-%a2
129 lea %sp@(32),%sp /* space for 8 regs */
131 addql #4,%sp /* orig d0 */
132 addl %sp@+,%sp /* stk adj */
133 addql #8,%sp /* remove exception */
134 movel %sp,sw_ksp /* save ksp */
135 subql #8,sw_usp /* set exception */
136 movel sw_usp,%sp /* restore usp */
140 movel %a0@(TI_FLAGS),%d1 /* get thread_info->flags */
141 btst #TIF_NEED_RESCHED,%d1
144 /* GERG: do we need something here for TRACEing?? */
147 subql #4,%sp /* dummy return address */
149 pea %sp@(SWITCH_STACK_SIZE)
158 * This is the generic interrupt handler (for all hardware interrupt
159 * sources). It figures out the vector number and calls the appropriate
160 * interrupt service routine directly.
165 movel %d0,%sp@(PT_ORIG_D0)
166 addql #1,local_irq_count
168 movew %sp@(PT_FORMATVEC),%d0 /* put exception # in d0 */
169 andl #0x03fc,%d0 /* mask out vector only */
171 leal per_cpu__kstat+STAT_IRQ,%a0
174 lsrl #2,%d0 /* calculate real vector # */
175 movel %d0,%d1 /* calculate array offset */
178 addl %d1,%a0 /* pointer to array struct */
180 movel %sp,%sp@- /* push regs arg onto stack */
181 movel %a0@(8),%sp@- /* push devid arg */
182 movel %d0,%sp@- /* push vector # on stack */
184 movel %a0@,%a0 /* get function to call */
185 jbsr %a0@ /* call vector handler */
186 lea %sp@(12),%sp /* pop parameters off stack */
188 bra ret_from_interrupt /* this was fallthrough */
191 * This is the fast interrupt handler (for certain hardware interrupt
192 * sources). Unlike the normal interrupt handler it just uses the
193 * current stack (doesn't care if it is user or kernel). It also
194 * doesn't bother doing the bottom half handlers.
199 movew %sp@(PT_FORMATVEC),%d0
200 andl #0x03fc,%d0 /* mask out vector only */
202 leal per_cpu__kstat+STAT_IRQ,%a0
205 movel %sp,%sp@- /* push regs arg onto stack */
206 clrl %sp@- /* push devid arg */
207 lsrl #2,%d0 /* calculate real vector # */
208 movel %d0,%sp@- /* push vector # on stack */
210 lsll #4,%d0 /* adjust for array offset */
212 movel %a0@(%d0),%a0 /* get function to call */
213 jbsr %a0@ /* call vector handler */
214 lea %sp@(12),%sp /* pop parameters off stack */
218 ENTRY(ret_from_interrupt)
219 subql #1,local_irq_count
224 moveb %sp@(PT_SR),%d0
228 /* check if we need to do software interrupts */
229 movel irq_stat+CPUSTAT_SOFTIRQ_PENDING,%d0
230 jeq ret_from_exception
232 pea ret_from_exception
236 * Beware - when entering resume, prev (the current task) is
237 * in a0, next (the new task) is in a1,so don't change these
238 * registers until their contents are no longer needed.
241 movel %a0, %d1 /* get prev thread in d1 */
243 movew %sr,%d0 /* save thread status reg */
244 movew %d0,%a0@(TASK_THREAD+THREAD_SR)
246 oril #0x700,%d0 /* disable interrupts */
249 movel sw_usp,%d0 /* save usp */
250 movel %d0,%a0@(TASK_THREAD+THREAD_USP)
253 movel %sp,%a0@(TASK_THREAD+THREAD_KSP) /* save kernel stack pointer */
254 movel %a1@(TASK_THREAD+THREAD_KSP),%sp /* restore new thread stack */
257 movel %a1@(TASK_THREAD+THREAD_USP),%a0 /* restore thread user stack */
260 movew %a1@(TASK_THREAD+THREAD_SR),%d0 /* restore thread status reg */