1 /* SPDX-License-Identifier: GPL-2.0-only */ !! 1 /* SPDX-License-Identifier: GPL-2.0-or-later
2 /* !! 2 * -*- mode: asm -*-
3 * Common Low Level Interrupts/Traps/Exception !! 3 *
4 * (included from entry-<isa>.S !! 4 * linux/arch/m68k/kernel/entry.S
>> 5 *
>> 6 * Copyright (C) 1991, 1992 Linus Torvalds
>> 7 *
>> 8 * Linux/m68k support by Hamish Macdonald
>> 9 *
>> 10 * 68060 fixes by Jesper Skov
5 * 11 *
6 * Copyright (C) 2014-15 Synopsys, Inc. (www.s <<
7 * Copyright (C) 2004, 2007-2010, 2011-2012 Sy <<
8 */ 12 */
9 13
10 /*-------------------------------------------- !! 14 /*
11 * Function ABI !! 15 * entry.S contains the system-call and fault low-level handling routines.
12 *-------------------------------------------- !! 16 * This also contains the timer-interrupt handler, as well as all interrupts
>> 17 * and faults that can result in a task-switch.
>> 18 *
>> 19 * NOTE: This code handles signal-recognition, which happens every time
>> 20 * after a timer-interrupt and after each system call.
13 * 21 *
14 * Arguments r0 - r <<
15 * Caller Saved Registers r0 - r <<
16 * Callee Saved Registers r13- r <<
17 * Global Pointer (gp) r26 <<
18 * Frame Pointer (fp) r27 <<
19 * Stack Pointer (sp) r28 <<
20 * Branch link register (blink) r31 <<
21 *-------------------------------------------- <<
22 */ 22 */
23 23
24 ;################### Special Sys Call Wrappers !! 24 /*
25 !! 25 * 12/03/96 Jes: Currently we only support m68k single-cpu systems, so
26 ENTRY(sys_clone_wrapper) !! 26 * all pointers that used to be 'current' are now entry
27 SAVE_CALLEE_SAVED_USER !! 27 * number 0 in the 'current_set' list.
28 bl @sys_clone !! 28 *
29 DISCARD_CALLEE_SAVED_USER !! 29 * 6/05/00 RZ: addedd writeback completion after return from sighandler
30 !! 30 * for 68040
31 GET_CURR_THR_INFO_FLAGS r10 !! 31 */
32 and.f 0, r10, _TIF_SYSCALL_WORK <<
33 bnz tracesys_exit <<
34 <<
35 b .Lret_from_system_call <<
36 END(sys_clone_wrapper) <<
37 <<
38 ENTRY(sys_clone3_wrapper) <<
39 SAVE_CALLEE_SAVED_USER <<
40 bl @sys_clone3 <<
41 DISCARD_CALLEE_SAVED_USER <<
42 <<
43 GET_CURR_THR_INFO_FLAGS r10 <<
44 and.f 0, r10, _TIF_SYSCALL_WORK <<
45 bnz tracesys_exit <<
46 <<
47 b .Lret_from_system_call <<
48 END(sys_clone3_wrapper) <<
49 <<
50 ENTRY(ret_from_fork) <<
51 ; when the forked child comes here fro <<
52 ; r0 has the last task pointer. <<
53 ; put last task in scheduler queue <<
54 jl @schedule_tail <<
55 <<
56 ld r9, [sp, PT_status32] <<
57 brne r9, 0, 1f <<
58 <<
59 jl.d [r14] ; kernel threa <<
60 mov r0, r13 ; (see PF_KTHR <<
61 <<
62 1: <<
63 ; Return to user space <<
64 ; 1. Any forked task (Reach here via B <<
65 ; 2. First ever init task (Reach here <<
66 ; This is the historic "kernel_exec <<
67 ; user mode, in a round about way s <<
68 ; a kernel thread which is executed <<
69 ; out whenever kernel_execve (now i <<
70 b ret_from_exception <<
71 END(ret_from_fork) <<
72 <<
73 ;################### Non TLB Exception Handlin <<
74 <<
75 ; -------------------------------------------- <<
76 ; Instruction Error Exception Handler <<
77 ; -------------------------------------------- <<
78 <<
79 ENTRY(instr_service) <<
80 <<
81 EXCEPTION_PROLOGUE <<
82 <<
83 bl do_insterror_or_kprobe <<
84 b ret_from_exception <<
85 END(instr_service) <<
86 <<
87 ; -------------------------------------------- <<
88 ; Machine Check Exception Handler <<
89 ; -------------------------------------------- <<
90 <<
91 ENTRY(EV_MachineCheck) <<
92 <<
93 EXCEPTION_PROLOGUE_KEEP_AE ; ECR <<
94 <<
95 lr r0, [efa] <<
96 mov r1, sp <<
97 <<
98 ; MC exceptions disable MMU <<
99 ARC_MMU_REENABLE r3 <<
100 <<
101 lsr r3, r10, 8 <<
102 bmsk r3, r3, 7 <<
103 brne r3, ECR_C_MCHK_DUP_TLB, 1f <<
104 32
105 bl do_tlb_overlap_fault !! 33 #include <linux/linkage.h>
106 b ret_from_exception !! 34 #include <asm/errno.h>
>> 35 #include <asm/setup.h>
>> 36 #include <asm/traps.h>
>> 37 #include <asm/unistd.h>
>> 38 #include <asm/asm-offsets.h>
>> 39 #include <asm/entry.h>
>> 40
>> 41 .globl system_call, buserr, trap, resume
>> 42 .globl sys_call_table
>> 43 .globl __sys_fork, __sys_clone, __sys_vfork
>> 44 .globl bad_interrupt
>> 45 .globl auto_irqhandler_fixup
>> 46 .globl user_irqvec_fixup
>> 47
>> 48 .text
>> 49 ENTRY(__sys_fork)
>> 50 SAVE_SWITCH_STACK
>> 51 jbsr sys_fork
>> 52 lea %sp@(24),%sp
>> 53 rts
>> 54
>> 55 ENTRY(__sys_clone)
>> 56 SAVE_SWITCH_STACK
>> 57 pea %sp@(SWITCH_STACK_SIZE)
>> 58 jbsr m68k_clone
>> 59 lea %sp@(28),%sp
>> 60 rts
>> 61
>> 62 ENTRY(__sys_vfork)
>> 63 SAVE_SWITCH_STACK
>> 64 jbsr sys_vfork
>> 65 lea %sp@(24),%sp
>> 66 rts
>> 67
>> 68 ENTRY(__sys_clone3)
>> 69 SAVE_SWITCH_STACK
>> 70 pea %sp@(SWITCH_STACK_SIZE)
>> 71 jbsr m68k_clone3
>> 72 lea %sp@(28),%sp
>> 73 rts
>> 74
>> 75 ENTRY(sys_sigreturn)
>> 76 SAVE_SWITCH_STACK
>> 77 movel %sp,%a1 | switch_stack pointer
>> 78 lea %sp@(SWITCH_STACK_SIZE),%a0 | pt_regs pointer
>> 79 lea %sp@(-84),%sp | leave a gap
>> 80 movel %a1,%sp@-
>> 81 movel %a0,%sp@-
>> 82 jbsr do_sigreturn
>> 83 jra 1f | shared with rt_sigreturn()
>> 84
>> 85 ENTRY(sys_rt_sigreturn)
>> 86 SAVE_SWITCH_STACK
>> 87 movel %sp,%a1 | switch_stack pointer
>> 88 lea %sp@(SWITCH_STACK_SIZE),%a0 | pt_regs pointer
>> 89 lea %sp@(-84),%sp | leave a gap
>> 90 movel %a1,%sp@-
>> 91 movel %a0,%sp@-
>> 92 | stack contents:
>> 93 | [original pt_regs address] [original switch_stack address]
>> 94 | [gap] [switch_stack] [pt_regs] [exception frame]
>> 95 jbsr do_rt_sigreturn
107 96
108 1: 97 1:
109 ; DEAD END: can't do much, display Reg !! 98 | stack contents now:
110 SAVE_CALLEE_SAVED_USER !! 99 | [original pt_regs address] [original switch_stack address]
111 !! 100 | [unused part of the gap] [moved switch_stack] [moved pt_regs]
112 GET_CURR_TASK_FIELD_PTR TASK_THREAD, !! 101 | [replacement exception frame]
113 st sp, [r10, THREAD_CALLEE_REG] !! 102 | return value of do_{rt_,}sigreturn() points to moved switch_stack.
114 !! 103
115 j do_machine_check_fault !! 104 movel %d0,%sp | discard the leftover junk
116 !! 105 RESTORE_SWITCH_STACK
117 END(EV_MachineCheck) !! 106 | stack contents now is just [syscall return address] [pt_regs] [frame]
118 !! 107 | return pt_regs.d0
119 ; -------------------------------------------- !! 108 movel %sp@(PT_OFF_D0+4),%d0
120 ; Privilege Violation Exception Handler !! 109 rts
121 ; -------------------------------------------- !! 110
122 ENTRY(EV_PrivilegeV) !! 111 ENTRY(buserr)
123 !! 112 SAVE_ALL_INT
124 EXCEPTION_PROLOGUE !! 113 GET_CURRENT(%d0)
125 !! 114 movel %sp,%sp@- | stack frame pointer argument
126 bl do_privilege_fault !! 115 jbsr buserr_c
127 b ret_from_exception !! 116 addql #4,%sp
128 END(EV_PrivilegeV) !! 117 jra ret_from_exception
129 !! 118
130 ; -------------------------------------------- !! 119 ENTRY(trap)
131 ; Extension Instruction Exception Handler !! 120 SAVE_ALL_INT
132 ; -------------------------------------------- !! 121 GET_CURRENT(%d0)
133 ENTRY(EV_Extension) !! 122 movel %sp,%sp@- | stack frame pointer argument
134 !! 123 jbsr trap_c
135 EXCEPTION_PROLOGUE !! 124 addql #4,%sp
136 !! 125 jra ret_from_exception
137 bl do_extension_fault !! 126
138 b ret_from_exception !! 127 | After a fork we jump here directly from resume,
139 END(EV_Extension) !! 128 | so that %d1 contains the previous task
140 !! 129 | schedule_tail now used regardless of CONFIG_SMP
141 ;################ Trap Handling (Syscall, Brea !! 130 ENTRY(ret_from_fork)
142 !! 131 movel %d1,%sp@-
143 ; -------------------------------------------- !! 132 jsr schedule_tail
144 ; syscall Tracing !! 133 addql #4,%sp
145 ; -------------------------------------------- !! 134 jra ret_from_exception
146 tracesys: !! 135
147 ; safekeep EFA (r12) if syscall tracer !! 136 ENTRY(ret_from_kernel_thread)
148 ; for traps, ERET is pre-commit so poi !! 137 | a3 contains the kernel thread payload, d7 - its argument
149 GET_CURR_TASK_FIELD_PTR TASK_THREAD, !! 138 movel %d1,%sp@-
150 st r12, [r11, THREAD_FAULT_ADDR] !! 139 jsr schedule_tail
151 !! 140 movel %d7,(%sp)
152 ; PRE syscall trace hook !! 141 jsr %a3@
153 mov r0, sp !! 142 addql #4,%sp
154 bl @syscall_trace_enter !! 143 jra ret_from_exception
155 !! 144
156 ; Tracing code now returns the syscall !! 145 #if defined(CONFIG_COLDFIRE) || !defined(CONFIG_MMU)
157 mov r8, r0 !! 146
158 !! 147 #ifdef TRAP_DBG_INTERRUPT
159 ; Do the Sys Call as we normally would !! 148
160 cmp r8, NR_syscalls - 1 !! 149 .globl dbginterrupt
161 mov.hi r0, -ENOSYS !! 150 ENTRY(dbginterrupt)
162 bhi tracesys_exit !! 151 SAVE_ALL_INT
163 !! 152 GET_CURRENT(%d0)
164 ; Restore the sys-call args. Mere invo !! 153 movel %sp,%sp@- /* stack frame pointer argument */
165 ; clobbered them (since they are in sc !! 154 jsr dbginterrupt_c
166 ; have deliberately changed the syscal !! 155 addql #4,%sp
167 ld r0, [sp, PT_r0] !! 156 jra ret_from_exception
168 ld r1, [sp, PT_r1] !! 157 #endif
169 ld r2, [sp, PT_r2] <<
170 ld r3, [sp, PT_r3] <<
171 ld r4, [sp, PT_r4] <<
172 ld r5, [sp, PT_r5] <<
173 ld r6, [sp, PT_r6] <<
174 ld r7, [sp, PT_r7] <<
175 ld.as r9, [sys_call_table, r8] <<
176 jl [r9] <<
177 <<
178 tracesys_exit: <<
179 st r0, [sp, PT_r0] <<
180 <<
181 ; POST syscall trace hook <<
182 mov r0, sp ; pt_regs need <<
183 bl @syscall_trace_exit <<
184 <<
185 ; don't call ret_from_system_call as i <<
186 b ret_from_exception <<
187 <<
188 ; -------------------------------------------- <<
189 ; Breakpoint TRAP <<
190 ; -------------------------------------------- <<
191 trap_with_param: <<
192 mov r0, r12 ; EFA in case ptracer/ <<
193 mov r1, sp ; pt_regs <<
194 <<
195 ; save callee regs in case tracer/gdb <<
196 SAVE_CALLEE_SAVED_USER <<
197 <<
198 ; safekeep ref to callee regs <<
199 GET_CURR_TASK_FIELD_PTR TASK_THREAD, <<
200 st sp, [r10, THREAD_CALLEE_REG] <<
201 <<
202 ; call the non syscall trap handler <<
203 bl do_non_swi_trap <<
204 <<
205 ; unwind stack to discard callee regs <<
206 DISCARD_CALLEE_SAVED_USER <<
207 <<
208 b ret_from_exception <<
209 <<
210 ; -------------------------------------------- <<
211 ; syscall TRAP <<
212 ; ABI: (r0-r7) up to 8 args, (r8) syscall numb <<
213 ; -------------------------------------------- <<
214 <<
215 ENTRY(EV_Trap) <<
216 <<
217 EXCEPTION_PROLOGUE_KEEP_AE <<
218 <<
219 lr r12, [efa] <<
220 <<
221 FAKE_RET_FROM_EXCPN <<
222 <<
223 ;============ TRAP N : breakpoints, kp <<
224 bmsk.f 0, r10, 7 <<
225 bnz trap_with_param <<
226 <<
227 ;============ TRAP 0 (no param): sysca <<
228 <<
229 ; syscall tracing ongoing, invoke pre- <<
230 GET_CURR_THR_INFO_FLAGS r10 <<
231 and.f 0, r10, _TIF_SYSCALL_WORK <<
232 bnz tracesys ; this never comes bac <<
233 <<
234 ;============ Normal syscall case <<
235 <<
236 cmp r8, NR_syscalls - 1 <<
237 mov.hi r0, -ENOSYS <<
238 bhi .Lret_from_system_call <<
239 <<
240 ld.as r9,[sys_call_table, r8] <<
241 jl [r9] <<
242 <<
243 .Lret_from_system_call: <<
244 st r0, [sp, PT_r0] ; sys call ret <<
245 158
246 ; fall through to ret_from_exception !! 159 ENTRY(reschedule)
247 END(EV_Trap) !! 160 /* save top of frame */
>> 161 pea %sp@
>> 162 jbsr set_esp0
>> 163 addql #4,%sp
>> 164 pea ret_from_exception
>> 165 jmp schedule
>> 166
>> 167 ENTRY(ret_from_user_signal)
>> 168 moveq #__NR_sigreturn,%d0
>> 169 trap #0
>> 170
>> 171 ENTRY(ret_from_user_rt_signal)
>> 172 movel #__NR_rt_sigreturn,%d0
>> 173 trap #0
>> 174
>> 175 #else
>> 176
>> 177 do_trace_entry:
>> 178 movel #-ENOSYS,%sp@(PT_OFF_D0)| needed for strace
>> 179 subql #4,%sp
>> 180 SAVE_SWITCH_STACK
>> 181 jbsr syscall_trace_enter
>> 182 RESTORE_SWITCH_STACK
>> 183 addql #4,%sp
>> 184 addql #1,%d0 | optimization for cmpil #-1,%d0
>> 185 jeq ret_from_syscall
>> 186 movel %sp@(PT_OFF_ORIG_D0),%d0
>> 187 cmpl #NR_syscalls,%d0
>> 188 jcs syscall
>> 189 jra ret_from_syscall
>> 190 badsys:
>> 191 movel #-ENOSYS,%sp@(PT_OFF_D0)
>> 192 jra ret_from_syscall
>> 193
>> 194 do_trace_exit:
>> 195 subql #4,%sp
>> 196 SAVE_SWITCH_STACK
>> 197 jbsr syscall_trace_leave
>> 198 RESTORE_SWITCH_STACK
>> 199 addql #4,%sp
>> 200 jra .Lret_from_exception
>> 201
>> 202 ENTRY(system_call)
>> 203 SAVE_ALL_SYS
>> 204
>> 205 GET_CURRENT(%d1)
>> 206 movel %d1,%a1
>> 207
>> 208 | save top of frame
>> 209 movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
>> 210
>> 211 | syscall trace?
>> 212 tstb %a1@(TINFO_FLAGS+2)
>> 213 jmi do_trace_entry
>> 214 | seccomp filter active?
>> 215 btst #5,%a1@(TINFO_FLAGS+2)
>> 216 bnes do_trace_entry
>> 217 cmpl #NR_syscalls,%d0
>> 218 jcc badsys
>> 219 syscall:
>> 220 jbsr @(sys_call_table,%d0:l:4)@(0)
>> 221 movel %d0,%sp@(PT_OFF_D0) | save the return value
>> 222 ret_from_syscall:
>> 223 |oriw #0x0700,%sr
>> 224 movel %curptr@(TASK_STACK),%a1
>> 225 movew %a1@(TINFO_FLAGS+2),%d0
>> 226 jne syscall_exit_work
>> 227 1: RESTORE_ALL
>> 228
>> 229 syscall_exit_work:
>> 230 btst #5,%sp@(PT_OFF_SR) | check if returning to kernel
>> 231 bnes 1b | if so, skip resched, signals
>> 232 lslw #1,%d0
>> 233 jcs do_trace_exit
>> 234 jmi do_delayed_trace
>> 235 lslw #8,%d0
>> 236 jne do_signal_return
>> 237 pea resume_userspace
>> 238 jra schedule
248 239
249 ;############# Return from Intr/Excp/Trap (Lin <<
250 ; <<
251 ; If ret to user mode do we need to handle sig <<
252 240
253 ENTRY(ret_from_exception) 241 ENTRY(ret_from_exception)
254 !! 242 .Lret_from_exception:
255 ; Pre-{IRQ,Trap,Exception} K/U mode fr !! 243 btst #5,%sp@(PT_OFF_SR) | check if returning to kernel
256 ld r8, [sp, PT_status32] ; returnin !! 244 bnes 1f | if so, skip resched, signals
257 !! 245 | only allow interrupts when we are really the last one on the
258 bbit0 r8, STATUS_U_BIT, resume_kernel !! 246 | kernel stack, otherwise stack overflow can occur during
259 !! 247 | heavy interrupt load
260 ; Before returning to User mode check- !! 248 andw #ALLOWINT,%sr
261 ; such as rescheduling/signal-delivery !! 249
262 resume_user_mode_begin: !! 250 resume_userspace:
263 !! 251 movel %curptr@(TASK_STACK),%a1
264 ; Disable IRQs to ensures that chk for !! 252 moveb %a1@(TINFO_FLAGS+3),%d0
265 ; (and we don't end up missing a NEED_ !! 253 jne exit_work
266 ; interim IRQ). !! 254 1: RESTORE_ALL
267 IRQ_DISABLE r10 !! 255
268 !! 256 exit_work:
269 ; Fast Path return to user mode if no !! 257 | save top of frame
270 GET_CURR_THR_INFO_FLAGS r9 !! 258 movel %sp,%curptr@(TASK_THREAD+THREAD_ESP0)
271 and.f 0, r9, _TIF_WORK_MASK !! 259 lslb #1,%d0
272 bz .Lrestore_regs !! 260 jne do_signal_return
273 !! 261 pea resume_userspace
274 ; --- (Slow Path #1) task preemption - !! 262 jra schedule
275 bbit0 r9, TIF_NEED_RESCHED, .Lchk_pen !! 263
276 mov blink, resume_user_mode_begin !! 264
277 j @schedule ; BTST+Bnz cau !! 265 do_signal_return:
278 !! 266 |andw #ALLOWINT,%sr
279 .Lchk_pend_signals: !! 267 subql #4,%sp | dummy return address
280 IRQ_ENABLE r10 !! 268 SAVE_SWITCH_STACK
281 !! 269 pea %sp@(SWITCH_STACK_SIZE)
282 ; --- (Slow Path #2) pending signal - !! 270 bsrl do_notify_resume
283 mov r0, sp ; pt_regs for arg to d !! 271 addql #4,%sp
284 !! 272 RESTORE_SWITCH_STACK
285 GET_CURR_THR_INFO_FLAGS r9 !! 273 addql #4,%sp
286 and.f 0, r9, _TIF_SIGPENDING|_TIF_NO !! 274 jbra resume_userspace
287 bz .Lchk_notify_resume !! 275
288 !! 276 do_delayed_trace:
289 ; Normal Trap/IRQ entry only saves Scr !! 277 bclr #7,%sp@(PT_OFF_SR) | clear trace bit in SR
290 ; in pt_reg since the "C" ABI (kernel !! 278 pea 1 | send SIGTRAP
291 ; save/restore callee-saved regs. !! 279 movel %curptr,%sp@-
292 ; !! 280 pea LSIGTRAP
293 ; However, here we need to explicitly !! 281 jbsr send_sig
294 ; (i) If this signal causes coredump !! 282 addql #8,%sp
295 ; (ii) If signal is SIGTRAP/SIGSTOP, t !! 283 addql #4,%sp
296 ; tracer might call PEEKUSR(CALLE !! 284 jbra resume_userspace
297 ; !! 285
298 ; NOTE: SP will grow up by size of CAL !! 286
299 SAVE_CALLEE_SAVED_USER !! 287 /* This is the main interrupt handler for autovector interrupts */
300 !! 288
301 ; save location of saved Callee Regs @ !! 289 ENTRY(auto_inthandler)
302 GET_CURR_TASK_FIELD_PTR TASK_THREAD, !! 290 SAVE_ALL_INT
303 st sp, [r10, THREAD_CALLEE_REG] !! 291 GET_CURRENT(%d0)
304 !! 292 | put exception # in d0
305 bl @do_signal !! 293 bfextu %sp@(PT_OFF_FORMATVEC){#4,#10},%d0
306 !! 294 subw #VEC_SPUR,%d0
307 ; Ideally we want to discard the Calle !! 295
308 ; a tracing signal, tracer could have !! 296 movel %sp,%sp@-
309 RESTORE_CALLEE_SAVED_USER !! 297 movel %d0,%sp@- | put vector # on stack
310 !! 298 auto_irqhandler_fixup = . + 2
311 b resume_user_mode_begin ; loop !! 299 jsr do_IRQ | process the IRQ
312 !! 300 addql #8,%sp | pop parameters off stack
313 ; --- (Slow Path #3) notify_resume --- !! 301 jra ret_from_exception
314 .Lchk_notify_resume: !! 302
315 btst r9, TIF_NOTIFY_RESUME !! 303 /* Handler for user defined interrupt vectors */
316 blnz @do_notify_resume !! 304
317 b resume_user_mode_begin ; unco !! 305 ENTRY(user_inthandler)
318 ; for !! 306 SAVE_ALL_INT
319 !! 307 GET_CURRENT(%d0)
320 resume_kernel_mode: !! 308 | put exception # in d0
321 !! 309 bfextu %sp@(PT_OFF_FORMATVEC){#4,#10},%d0
322 ; Disable Interrupts from this point o !! 310 user_irqvec_fixup = . + 2
323 ; CONFIG_PREEMPTION: This is a must fo !! 311 subw #VEC_USER,%d0
324 ; !CONFIG_PREEMPTION: To ensure restor !! 312
325 IRQ_DISABLE r9 !! 313 movel %sp,%sp@-
326 !! 314 movel %d0,%sp@- | put vector # on stack
327 #ifdef CONFIG_PREEMPTION !! 315 jsr do_IRQ | process the IRQ
328 !! 316 addql #8,%sp | pop parameters off stack
329 ; Can't preempt if preemption disabled !! 317 jra ret_from_exception
330 GET_CURR_THR_INFO_FROM_SP r10 !! 318
331 ld r8, [r10, THREAD_INFO_PREEMPT_COUN !! 319 /* Handler for uninitialized and spurious interrupts */
332 brne r8, 0, .Lrestore_regs !! 320
333 !! 321 ENTRY(bad_inthandler)
334 ; check if this task's NEED_RESCHED fl !! 322 SAVE_ALL_INT
335 ld r9, [r10, THREAD_INFO_FLAGS] !! 323 GET_CURRENT(%d0)
336 bbit0 r9, TIF_NEED_RESCHED, .Lrestore !! 324
337 !! 325 movel %sp,%sp@-
338 ; Invoke PREEMPTION !! 326 jsr handle_badint
339 jl preempt_schedule_irq !! 327 addql #4,%sp
340 !! 328 jra ret_from_exception
341 ; preempt_schedule_irq() always return !! 329
>> 330 resume:
>> 331 /*
>> 332 * Beware - when entering resume, prev (the current task) is
>> 333 * in a0, next (the new task) is in a1,so don't change these
>> 334 * registers until their contents are no longer needed.
>> 335 */
>> 336
>> 337 /* save sr */
>> 338 movew %sr,%a0@(TASK_THREAD+THREAD_SR)
>> 339
>> 340 /* save fs (sfc,%dfc) (may be pointing to kernel memory) */
>> 341 movec %sfc,%d0
>> 342 movew %d0,%a0@(TASK_THREAD+THREAD_FC)
>> 343
>> 344 /* save usp */
>> 345 /* it is better to use a movel here instead of a movew 8*) */
>> 346 movec %usp,%d0
>> 347 movel %d0,%a0@(TASK_THREAD+THREAD_USP)
>> 348
>> 349 /* save non-scratch registers on stack */
>> 350 SAVE_SWITCH_STACK
>> 351
>> 352 /* save current kernel stack pointer */
>> 353 movel %sp,%a0@(TASK_THREAD+THREAD_KSP)
>> 354
>> 355 /* save floating point context */
>> 356 #ifndef CONFIG_M68KFPU_EMU_ONLY
>> 357 #ifdef CONFIG_M68KFPU_EMU
>> 358 tstl m68k_fputype
>> 359 jeq 3f
342 #endif 360 #endif
>> 361 fsave %a0@(TASK_THREAD+THREAD_FPSTATE)
343 362
344 b .Lrestore_regs !! 363 #if defined(CONFIG_M68060)
>> 364 #if !defined(CPU_M68060_ONLY)
>> 365 btst #3,m68k_cputype+3
>> 366 beqs 1f
>> 367 #endif
>> 368 /* The 060 FPU keeps status in bits 15-8 of the first longword */
>> 369 tstb %a0@(TASK_THREAD+THREAD_FPSTATE+2)
>> 370 jeq 3f
>> 371 #if !defined(CPU_M68060_ONLY)
>> 372 jra 2f
>> 373 #endif
>> 374 #endif /* CONFIG_M68060 */
>> 375 #if !defined(CPU_M68060_ONLY)
>> 376 1: tstb %a0@(TASK_THREAD+THREAD_FPSTATE)
>> 377 jeq 3f
>> 378 #endif
>> 379 2: fmovemx %fp0-%fp7,%a0@(TASK_THREAD+THREAD_FPREG)
>> 380 fmoveml %fpcr/%fpsr/%fpiar,%a0@(TASK_THREAD+THREAD_FPCNTL)
>> 381 3:
>> 382 #endif /* CONFIG_M68KFPU_EMU_ONLY */
>> 383 /* Return previous task in %d1 */
>> 384 movel %curptr,%d1
>> 385
>> 386 /* switch to new task (a1 contains new task) */
>> 387 movel %a1,%curptr
>> 388
>> 389 /* restore floating point context */
>> 390 #ifndef CONFIG_M68KFPU_EMU_ONLY
>> 391 #ifdef CONFIG_M68KFPU_EMU
>> 392 tstl m68k_fputype
>> 393 jeq 4f
>> 394 #endif
>> 395 #if defined(CONFIG_M68060)
>> 396 #if !defined(CPU_M68060_ONLY)
>> 397 btst #3,m68k_cputype+3
>> 398 beqs 1f
>> 399 #endif
>> 400 /* The 060 FPU keeps status in bits 15-8 of the first longword */
>> 401 tstb %a1@(TASK_THREAD+THREAD_FPSTATE+2)
>> 402 jeq 3f
>> 403 #if !defined(CPU_M68060_ONLY)
>> 404 jra 2f
>> 405 #endif
>> 406 #endif /* CONFIG_M68060 */
>> 407 #if !defined(CPU_M68060_ONLY)
>> 408 1: tstb %a1@(TASK_THREAD+THREAD_FPSTATE)
>> 409 jeq 3f
>> 410 #endif
>> 411 2: fmovemx %a1@(TASK_THREAD+THREAD_FPREG),%fp0-%fp7
>> 412 fmoveml %a1@(TASK_THREAD+THREAD_FPCNTL),%fpcr/%fpsr/%fpiar
>> 413 3: frestore %a1@(TASK_THREAD+THREAD_FPSTATE)
>> 414 4:
>> 415 #endif /* CONFIG_M68KFPU_EMU_ONLY */
>> 416
>> 417 /* restore the kernel stack pointer */
>> 418 movel %a1@(TASK_THREAD+THREAD_KSP),%sp
>> 419
>> 420 /* restore non-scratch registers */
>> 421 RESTORE_SWITCH_STACK
>> 422
>> 423 /* restore user stack pointer */
>> 424 movel %a1@(TASK_THREAD+THREAD_USP),%a0
>> 425 movel %a0,%usp
>> 426
>> 427 /* restore fs (sfc,%dfc) */
>> 428 movew %a1@(TASK_THREAD+THREAD_FC),%a0
>> 429 movec %a0,%sfc
>> 430 movec %a0,%dfc
>> 431
>> 432 /* restore status register */
>> 433 movew %a1@(TASK_THREAD+THREAD_SR),%d0
>> 434 oriw #0x0700,%d0
>> 435 movew %d0,%sr
345 436
346 ##### DONT ADD CODE HERE - .Lrestore_regs actu !! 437 rts
347 438
>> 439 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */
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