| blob | c0163bf94a5001a3fe123d315e87ab83bc629a3d |
1 /* $Id: entry.S,v 1.28 2005/06/20 05:06:30 starvik Exp $
2 *
3 * linux/arch/cris/entry.S
4 *
5 * Copyright (C) 2000, 2001, 2002 Axis Communications AB
6 *
7 * Authors: Bjorn Wesen (bjornw@axis.com)
8 *
9 * $Log: entry.S,v $
10 * Revision 1.28 2005/06/20 05:06:30 starvik
11 * Remove unnecessary diff to kernel.org tree
12 *
13 * Revision 1.27 2005/03/04 08:16:16 starvik
14 * Merge of Linux 2.6.11.
15 *
16 * Revision 1.26 2005/01/11 13:49:47 starvik
17 * Added NMI handler.
18 *
19 * Revision 1.25 2004/12/27 11:18:32 starvik
20 * Merge of Linux 2.6.10 (not functional yet).
21 *
22 * Revision 1.24 2004/12/22 10:41:23 starvik
23 * Updates to make v10 compile with the latest SMP aware generic code (even
24 * though v10 will never have SMP).
25 *
26 * Revision 1.23 2004/10/19 13:07:37 starvik
27 * Merge of Linux 2.6.9
28 *
29 * Revision 1.22 2004/06/21 10:29:55 starvik
30 * Merge of Linux 2.6.7
31 *
32 * Revision 1.21 2004/06/09 05:30:27 starvik
33 * Clean up multiple interrupt handling.
34 * Prevent interrupts from interrupting each other.
35 * Handle all active interrupts.
36 *
37 * Revision 1.20 2004/06/08 08:55:32 starvik
38 * Removed unused code
39 *
40 * Revision 1.19 2004/06/04 11:56:15 starvik
41 * Implemented page table lookup for refills in assembler for improved performance.
42 *
43 * Revision 1.18 2004/05/11 12:28:25 starvik
44 * Merge of Linux 2.6.6
45 *
46 * Revision 1.17 2003/09/11 07:29:49 starvik
47 * Merge of Linux 2.6.0-test5
48 *
49 * Revision 1.16 2003/07/04 08:27:41 starvik
50 * Merge of Linux 2.5.74
51 *
52 * Revision 1.15 2003/04/09 07:32:55 starvik
53 * resume should return task_struct, not thread_info
54 *
55 * Revision 1.14 2003/04/09 05:20:44 starvik
56 * Merge of Linux 2.5.67
57 *
58 * Revision 1.13 2002/12/11 15:42:02 starvik
59 * Extracted v10 (ETRAX 100LX) specific stuff from arch/cris/kernel/*.c
60 *
61 * Revision 1.12 2002/12/10 09:00:10 starvik
62 * Merge of Linux 2.5.51
63 *
64 * Revision 1.11 2002/12/05 07:53:10 starvik
65 * Corrected constants used with btstq
66 *
67 * Revision 1.10 2002/11/27 08:45:10 starvik
68 * pid is in task_struct, not thread_info
69 *
70 * Revision 1.9 2002/11/26 09:52:05 starvik
71 * Added preemptive kernel scheduling (if CONFIG_PREEMPT)
72 *
73 * Revision 1.8 2002/11/20 11:56:11 starvik
74 * Merge of Linux 2.5.48
75 *
76 * Revision 1.7 2002/11/18 13:02:42 starvik
77 * Added fourth parameter to do_notify_resume
78 * Minor cleanup
79 *
80 * Revision 1.6 2002/11/11 10:37:50 starvik
81 * Use new asm-offset defines
82 * Modified for new location of current->work etc
83 * Removed SYMBOL_NAME from syscalls
84 * Added some new syscalls
85 *
86 * Revision 1.5 2002/11/05 06:45:11 starvik
87 * Merge of Linux 2.5.45
88 *
89 * Revision 1.4 2002/02/05 15:41:31 bjornw
90 * Rewritten to conform better to current 2.5 code (similar to arch/i386)
91 *
92 * Revision 1.3 2002/01/21 15:22:20 bjornw
93 * NICE_DOGGY fix from 2.4 arch/cris
94 *
95 * Revision 1.37 2001/12/07 17:03:55 bjornw
96 * Call a c-hook called watchdog_bite_hook instead of show_registers directly
97 *
98 * Revision 1.36 2001/11/22 13:36:36 bjornw
99 * * In ret_from_intr, check regs->dccr for usermode reentrance instead of
100 * DCCR explicitely (because the latter might not reflect current reality)
101 * * In mmu_bus_fault, set $r9 _after_ calling the C-code instead of before
102 * since $r9 is call-clobbered and is potentially needed afterwards
103 *
104 * Revision 1.35 2001/10/30 17:10:15 bjornw
105 * Add some syscalls
106 *
107 * Revision 1.34 2001/10/01 14:45:03 bjornw
108 * Removed underscores and added register prefixes
109 *
110 * Revision 1.33 2001/08/21 13:48:01 jonashg
111 * Added fix by HP to avoid oops when doing a hard_reset_now.
112 *
113 * Revision 1.32 2001/08/14 04:32:02 hp
114 * In _resume, add comment why R9 is saved; don't sound like it's call-saved.
115 *
116 * Revision 1.31 2001/07/25 16:07:42 bjornw
117 * softirq_active/mask -> softirq_pending only
118 *
119 * Revision 1.30 2001/07/05 01:03:32 hp
120 * - include asm/errno.h to get ENOSYS.
121 * - Use ENOSYS, not local constant LENOSYS; tweak comments.
122 * - Explain why .include, not #include is used.
123 * - Make oops-register-dump if watchdog bits and it's not expected.
124 * - Don't jsr, use jump _hard_reset_now, and skip spurious nop.
125 * - Use correct section attribute for section .rodata.
126 * - Adjust sys_ni_syscall fill number.
127 *
128 * Revision 1.29 2001/06/25 14:07:00 hp
129 * Fix review comment.
130 * * head.S: Use IO_STATE, IO_FIELD and IO_MASK constructs instead of
131 * magic numbers. Add comment that -traditional must not be used.
132 * * entry.S (SYMBOL_NAME): Change redefinition to use ## concatenation.
133 * Correct and update comment.
134 * * Makefile (.S.o): Don't use -traditional. Add comment why the
135 * toplevel rule can't be used (now that there's a reason).
136 *
137 * Revision 1.28 2001/06/21 02:00:40 hp
138 * * entry.S: Include asm/unistd.h.
139 * (_sys_call_table): Use section .rodata, not .data.
140 * (_kernel_thread): Move from...
141 * * process.c: ... here.
142 * * entryoffsets.c (VAL): Break out from...
143 * (OF): Use VAL.
144 * (LCLONE_VM): New asmified value from CLONE_VM.
145 *
146 * Revision 1.27 2001/05/29 11:25:27 markusl
147 * In case of "spurious_interrupt", do hard_reset instead of hanging system in a loop...
148 *
149 * Revision 1.26 2001/05/15 15:46:03 bjornw
150 * Include config.h now that we use some CONFIG_ options
151 *
152 * Revision 1.25 2001/05/15 05:38:47 hp
153 * Tweaked code in _ret_from_sys_call
154 *
155 * Revision 1.24 2001/05/15 05:27:49 hp
156 * Save r9 in r1 over function call rather than on stack.
157 *
158 * Revision 1.23 2001/05/15 05:10:00 hp
159 * Generate entry.S structure offsets from C
160 *
161 * Revision 1.22 2001/04/17 13:58:39 orjanf
162 * * Renamed CONFIG_KGDB to CONFIG_ETRAX_KGDB.
163 *
164 * Revision 1.21 2001/04/17 11:33:29 orjanf
165 * Updated according to review:
166 * * Included asm/sv_addr_ag.h to get macro for internal register.
167 * * Corrected comment regarding system call argument passing.
168 * * Removed comment about instruction being in a delay slot.
169 * * Added comment about SYMBOL_NAME macro.
170 *
171 * Revision 1.20 2001/04/12 08:51:07 hp
172 * - Add entry for sys_fcntl64. In fact copy last piece from i386 including ...
173 * - .rept to fill table to safe state with sys_ni_syscall.
174 *
175 * Revision 1.19 2001/04/04 09:43:32 orjanf
176 * * Moved do_sigtrap from traps.c to entry.S.
177 * * LTASK_PID need not be global anymore.
178 *
179 * Revision 1.18 2001/03/26 09:25:02 markusl
180 * Updated after review, should now handle USB interrupts correctly.
181 *
182 * Revision 1.17 2001/03/21 16:12:55 bjornw
183 * * Always make room for the cpu status record in the frame, in order to
184 * use the same framelength and layout for both mmu busfaults and normal
185 * irqs. No need to check for the explicit CRIS_FRAME_FIXUP type anymore.
186 * * Fixed bug with using addq for popping the stack in the epilogue - it
187 * destroyed the flag register. Use instructions that don't affect the
188 * flag register instead.
189 * * Removed write to R_PORT_PA_DATA during spurious_interrupt
190 *
191 * Revision 1.16 2001/03/20 19:43:02 bjornw
192 * * Get rid of esp0 setting
193 * * Give a 7th argument to a systemcall - the stackframe
194 *
195 * Revision 1.15 2001/03/05 13:14:30 bjornw
196 * Spelling fix
197 *
198 * Revision 1.14 2001/02/23 08:36:36 perf
199 * New ABI; syscallnr=r9, arg5=mof, arg6=srp.
200 * Corrected tracesys call check.
201 *
202 * Revision 1.13 2001/02/15 08:40:55 perf
203 * H-P by way of perf;
204 * - (_system_call): Don't read system call function address into r1.
205 * - (RBFExit): There is no such thing as a null pop. Adjust sp by addq.
206 * - (_system_call): Don't use r10 and don't save and restore it.
207 * - (THREAD_ESP0): New constant.
208 * - (_system_call): Inline set_esp0.
209 *
210 * Revision 1.12 2001/01/31 17:56:25 orjanf
211 * Added definition of LTASK_PID and made it global.
212 *
213 * Revision 1.11 2001/01/10 21:13:29 bjornw
214 * SYMBOL_NAME is defined incorrectly for the compiler options we currently use
215 *
216 * Revision 1.10 2000/12/18 23:47:56 bjornw
217 * * Added syscall trace support (ptrace), completely untested of course
218 * * Removed redundant check for NULL entries in syscall_table
219 *
220 * Revision 1.9 2000/11/21 16:40:51 bjornw
221 * * New frame type used when an SBFS frame needs to be popped without
222 * actually restarting the instruction
223 * * Enable interrupts in signal_return (they did so in x86, I hope it's a good
224 * idea)
225 *
226 * Revision 1.8 2000/11/17 16:53:35 bjornw
227 * Added detection of frame-type in Rexit, so that mmu_bus_fault can
228 * use ret_from_intr in the return-path to check for signals (like SEGV)
229 * and other foul things that might have occurred during the fault.
230 *
231 * Revision 1.7 2000/10/06 15:04:28 bjornw
232 * Include mof in register savings
233 *
234 * Revision 1.6 2000/09/12 16:02:44 bjornw
235 * Linux-2.4.0-test7 derived updates
236 *
237 * Revision 1.5 2000/08/17 15:35:15 bjornw
238 * 2.4.0-test6 changed local_irq_count and friends API
239 *
240 * Revision 1.4 2000/08/02 13:59:30 bjornw
241 * Removed olduname and uname from the syscall list
242 *
243 * Revision 1.3 2000/07/31 13:32:58 bjornw
244 * * Export ret_from_intr
245 * * _resume updated (prev/last tjohejsan)
246 * * timer_interrupt obsolete
247 * * SIGSEGV detection in mmu_bus_fault temporarily disabled
248 *
249 *
250 */
252 /*
253 * entry.S contains the system-call and fault low-level handling routines.
254 *
255 * NOTE: This code handles signal-recognition, which happens every time
256 * after a timer-interrupt and after each system call.
257 *
258 * Stack layout in 'ret_from_system_call':
259 * ptrace needs to have all regs on the stack.
260 * if the order here is changed, it needs to be
261 * updated in fork.c:copy_process, signal.c:do_signal,
262 * ptrace.c and ptrace.h
263 *
264 */
266 #include <linux/config.h>
267 #include <linux/linkage.h>
268 #include <linux/sys.h>
269 #include <asm/unistd.h>
270 #include <asm/arch/sv_addr_ag.h>
271 #include <asm/errno.h>
272 #include <asm/thread_info.h>
273 #include <asm/arch/offset.h>
274 #include <asm/page.h>
275 #include <asm/pgtable.h>
277 ;; functions exported from this file
279 .globl system_call
280 .globl ret_from_intr
281 .globl ret_from_fork
282 .globl resume
283 .globl multiple_interrupt
284 .globl hwbreakpoint
285 .globl IRQ1_interrupt
286 .globl spurious_interrupt
287 .globl hw_bp_trigs
288 .globl mmu_bus_fault
289 .globl do_sigtrap
290 .globl gdb_handle_breakpoint
291 .globl sys_call_table
293 ;; below are various parts of system_call which are not in the fast-path
295 #ifdef CONFIG_PREEMPT
296 ; Check if preemptive kernel scheduling should be done
297 _resume_kernel:
298 di
299 ; Load current task struct
300 movs.w -8192, $r0 ; THREAD_SIZE = 8192
301 and.d $sp, $r0
302 move.d [$r0+TI_preempt_count], $r10 ; Preemption disabled?
303 bne _Rexit
304 nop
305 _need_resched:
306 move.d [$r0+TI_flags], $r10
307 btstq TIF_NEED_RESCHED, $r10 ; Check if need_resched is set
308 bpl _Rexit
309 nop
310 ; Ok, lets's do some preemptive kernel scheduling
311 jsr preempt_schedule_irq
312 ; Load new task struct
313 movs.w -8192, $r0 ; THREAD_SIZE = 8192
314 and.d $sp, $r0
315 ; One more time (with new task)
316 ba _need_resched
317 nop
318 #else
319 #define _resume_kernel _Rexit
320 #endif
322 ; Called at exit from fork. schedule_tail must be called to drop
323 ; spinlock if CONFIG_PREEMPT
324 ret_from_fork:
325 jsr schedule_tail
326 ba ret_from_sys_call
327 nop
329 ret_from_intr:
330 ;; check for resched if preemptive kernel or if we're going back to user-mode
331 ;; this test matches the user_regs(regs) macro
332 ;; we cannot simply test $dccr, because that does not necessarily
333 ;; reflect what mode we'll return into.
335 move.d [$sp + PT_dccr], $r0; regs->dccr
336 btstq 8, $r0 ; U-flag
337 bpl _resume_kernel
338 ; Note that di below is in delay slot
340 _resume_userspace:
341 di ; so need_resched and sigpending don't change
343 movs.w -8192, $r0 ; THREAD_SIZE == 8192
344 and.d $sp, $r0
346 move.d [$r0+TI_flags], $r10 ; current->work
347 and.d _TIF_WORK_MASK, $r10 ; is there any work to be done on return
348 bne _work_pending
349 nop
350 ba _Rexit
351 nop
353 ;; The system_call is called by a BREAK instruction, which works like
354 ;; an interrupt call but it stores the return PC in BRP instead of IRP.
355 ;; Since we dont really want to have two epilogues (one for system calls
356 ;; and one for interrupts) we push the contents of BRP instead of IRP in the
357 ;; system call prologue, to make it look like an ordinary interrupt on the
358 ;; stackframe.
359 ;;
360 ;; Since we can't have system calls inside interrupts, it should not matter
361 ;; that we don't stack IRP.
362 ;;
363 ;; In r9 we have the wanted syscall number. Arguments come in r10,r11,r12,r13,mof,srp
364 ;;
365 ;; This function looks on the _surface_ like spaghetti programming, but it's
366 ;; really designed so that the fast-path does not force cache-loading of non-used
367 ;; instructions. Only the non-common cases cause the outlined code to run..
369 system_call:
370 ;; stack-frame similar to the irq heads, which is reversed in ret_from_sys_call
371 move $brp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
372 push $srp
373 push $dccr
374 push $mof
375 subq 14*4, $sp ; make room for r0-r13
376 movem $r13, [$sp] ; push r0-r13
377 push $r10 ; push orig_r10
378 clear.d [$sp=$sp-4] ; frametype == 0, normal stackframe
380 movs.w -ENOSYS, $r0
381 move.d $r0, [$sp+PT_r10] ; put the default return value in r10 in the frame
383 ;; check if this process is syscall-traced
385 movs.w -8192, $r0 ; THREAD_SIZE == 8192
386 and.d $sp, $r0
388 move.d [$r0+TI_flags], $r0
389 btstq TIF_SYSCALL_TRACE, $r0
390 bmi _syscall_trace_entry
391 nop
393 _syscall_traced:
395 ;; check for sanity in the requested syscall number
397 cmpu.w NR_syscalls, $r9
398 bcc ret_from_sys_call
399 lslq 2, $r9 ; multiply by 4, in the delay slot
401 ;; as a bonus 7th parameter, we give the location on the stack
402 ;; of the register structure itself. some syscalls need this.
404 push $sp
406 ;; the parameter carrying registers r10, r11, r12 and 13 are intact.
407 ;; the fifth and sixth parameters (if any) was in mof and srp
408 ;; respectively, and we need to put them on the stack.
410 push $srp
411 push $mof
413 jsr [$r9+sys_call_table] ; actually do the system call
414 addq 3*4, $sp ; pop the mof, srp and regs parameters
415 move.d $r10, [$sp+PT_r10] ; save the return value
417 moveq 1, $r9 ; "parameter" to ret_from_sys_call to show it was a sys call
419 ;; fall through into ret_from_sys_call to return
421 ret_from_sys_call:
422 ;; r9 is a parameter - if >=1 we came from a syscall, if 0, from an irq
424 ;; get the current task-struct pointer (see top for defs)
426 movs.w -8192, $r0 ; THREAD_SIZE == 8192
427 and.d $sp, $r0
429 di ; make sure need_resched and sigpending don't change
430 move.d [$r0+TI_flags],$r1
431 and.d _TIF_ALLWORK_MASK, $r1
432 bne _syscall_exit_work
433 nop
435 _Rexit:
436 ;; this epilogue MUST match the prologues in multiple_interrupt, irq.h and ptregs.h
437 pop $r10 ; frametype
438 bne _RBFexit ; was not CRIS_FRAME_NORMAL, handle otherwise
439 addq 4, $sp ; skip orig_r10, in delayslot
440 movem [$sp+], $r13 ; registers r0-r13
441 pop $mof ; multiply overflow register
442 pop $dccr ; condition codes
443 pop $srp ; subroutine return pointer
444 ;; now we have a 4-word SBFS frame which we do not want to restore
445 ;; using RBF since it was not stacked with SBFS. instead we would like to
446 ;; just get the PC value to restart it with, and skip the rest of
447 ;; the frame.
448 ;; Also notice that it's important to use instructions here that
449 ;; keep the interrupts disabled (since we've already popped DCCR)
450 move [$sp=$sp+16], $p8; pop the SBFS frame from the sp
451 jmpu [$sp-16] ; return through the irp field in the sbfs frame
453 _RBFexit:
454 movem [$sp+], $r13 ; registers r0-r13, in delay slot
455 pop $mof ; multiply overflow register
456 pop $dccr ; condition codes
457 pop $srp ; subroutine return pointer
458 rbf [$sp+] ; return by popping the CPU status
460 ;; We get here after doing a syscall if extra work might need to be done
461 ;; perform syscall exit tracing if needed
463 _syscall_exit_work:
464 ;; $r0 contains current at this point and irq's are disabled
466 move.d [$r0+TI_flags], $r1
467 btstq TIF_SYSCALL_TRACE, $r1
468 bpl _work_pending
469 nop
471 ei
473 move.d $r9, $r1 ; preserve r9
474 jsr do_syscall_trace
475 move.d $r1, $r9
477 ba _resume_userspace
478 nop
480 _work_pending:
481 move.d [$r0+TI_flags], $r1
482 btstq TIF_NEED_RESCHED, $r1
483 bpl _work_notifysig ; was neither trace nor sched, must be signal/notify
484 nop
486 _work_resched:
487 move.d $r9, $r1 ; preserve r9
488 jsr schedule
489 move.d $r1, $r9
490 di
492 move.d [$r0+TI_flags], $r1
493 and.d _TIF_WORK_MASK, $r1; ignore the syscall trace counter
494 beq _Rexit
495 nop
496 btstq TIF_NEED_RESCHED, $r1
497 bmi _work_resched ; current->work.need_resched
498 nop
500 _work_notifysig:
501 ;; deal with pending signals and notify-resume requests
503 move.d $r9, $r10 ; do_notify_resume syscall/irq param
504 moveq 0, $r11 ; oldset param - 0 in this case
505 move.d $sp, $r12 ; the regs param
506 move.d $r1, $r13 ; the thread_info_flags parameter
507 jsr do_notify_resume
509 ba _Rexit
510 nop
512 ;; We get here as a sidetrack when we've entered a syscall with the
513 ;; trace-bit set. We need to call do_syscall_trace and then continue
514 ;; with the call.
516 _syscall_trace_entry:
517 ;; PT_r10 in the frame contains -ENOSYS as required, at this point
519 jsr do_syscall_trace
521 ;; now re-enter the syscall code to do the syscall itself
522 ;; we need to restore $r9 here to contain the wanted syscall, and
523 ;; the other parameter-bearing registers
525 move.d [$sp+PT_r9], $r9
526 move.d [$sp+PT_orig_r10], $r10 ; PT_r10 is already filled with -ENOSYS.
527 move.d [$sp+PT_r11], $r11
528 move.d [$sp+PT_r12], $r12
529 move.d [$sp+PT_r13], $r13
530 move [$sp+PT_mof], $mof
531 move [$sp+PT_srp], $srp
533 ba _syscall_traced
534 nop
536 ;; resume performs the actual task-switching, by switching stack pointers
537 ;; input arguments: r10 = prev, r11 = next, r12 = thread offset in task struct
538 ;; returns old current in r10
539 ;;
540 ;; TODO: see the i386 version. The switch_to which calls resume in our version
541 ;; could really be an inline asm of this.
543 resume:
544 push $srp ; we keep the old/new PC on the stack
545 add.d $r12, $r10 ; r10 = current tasks tss
546 move $dccr, [$r10+THREAD_dccr]; save irq enable state
547 di
549 move $usp, [$r10+ THREAD_usp] ; save user-mode stackpointer
551 ;; See copy_thread for the reason why register R9 is saved.
552 subq 10*4, $sp
553 movem $r9, [$sp] ; save non-scratch registers and R9.
555 move.d $sp, [$r10+THREAD_ksp] ; save the kernel stack pointer for the old task
556 move.d $sp, $r10 ; return last running task in r10
557 and.d -8192, $r10 ; get thread_info from stackpointer
558 move.d [$r10+TI_task], $r10 ; get task
559 add.d $r12, $r11 ; find the new tasks tss
560 move.d [$r11+THREAD_ksp], $sp ; switch into the new stackframe by restoring kernel sp
562 movem [$sp+], $r9 ; restore non-scratch registers and R9.
564 move [$r11+THREAD_usp], $usp ; restore user-mode stackpointer
566 move [$r11+THREAD_dccr], $dccr ; restore irq enable status
567 jump [$sp+] ; restore PC
569 ;; This is the MMU bus fault handler.
570 ;; It needs to stack the CPU status and overall is different
571 ;; from the other interrupt handlers.
573 mmu_bus_fault:
574 ;; For refills we try to do a quick page table lookup. If it is
575 ;; a real fault we let the mm subsystem handle it.
577 ;; the first longword in the sbfs frame was the interrupted PC
578 ;; which fits nicely with the "IRP" slot in pt_regs normally used to
579 ;; contain the return address. used by Oops to print kernel errors.
580 sbfs [$sp=$sp-16] ; push the internal CPU status
581 push $dccr
582 di
583 subq 2*4, $sp
584 movem $r1, [$sp]
585 move.d [R_MMU_CAUSE], $r1
586 ;; ETRAX 100LX TR89 bugfix: if the second half of an unaligned
587 ;; write causes a MMU-fault, it will not be restarted correctly.
588 ;; This could happen if a write crosses a page-boundary and the
589 ;; second page is not yet COW'ed or even loaded. The workaround
590 ;; is to clear the unaligned bit in the CPU status record, so
591 ;; that the CPU will rerun both the first and second halves of
592 ;; the instruction. This will not have any sideeffects unless
593 ;; the first half goes to any device or memory that can't be
594 ;; written twice, and which is mapped through the MMU.
595 ;;
596 ;; We only need to do this for writes.
597 btstq 8, $r1 ; Write access?
598 bpl 1f
599 nop
600 move.d [$sp+16], $r0 ; Clear unaligned bit in csrinstr
601 and.d ~(1<<5), $r0
602 move.d $r0, [$sp+16]
603 1: btstq 12, $r1 ; Refill?
604 bpl 2f
605 lsrq 24, $r1 ; Get PGD index (bit 24-31)
606 move.d [per_cpu__current_pgd], $r0 ; PGD for the current process
607 move.d [$r0+$r1.d], $r0 ; Get PMD
608 beq 2f
609 nop
610 and.w PAGE_MASK, $r0 ; Remove PMD flags
611 move.d [R_MMU_CAUSE], $r1
612 lsrq PAGE_SHIFT, $r1
613 and.d 0x7ff, $r1 ; Get PTE index into PGD (bit 13-23)
614 move.d [$r0+$r1.d], $r1 ; Get PTE
615 beq 2f
616 nop
617 ;; Store in TLB
618 move.d $r1, [R_TLB_LO]
619 ;; Return
620 movem [$sp+], $r1
621 pop $dccr
622 rbf [$sp+] ; return by popping the CPU status
624 2: ; PMD or PTE missing, let the mm subsystem fix it up.
625 movem [$sp+], $r1
626 pop $dccr
628 ; Ok, not that easy, pass it on to the mm subsystem
629 ; The MMU status record is now on the stack
630 push $srp ; make a stackframe similar to pt_regs
631 push $dccr
632 push $mof
633 di
634 subq 14*4, $sp
635 movem $r13, [$sp]
636 push $r10 ; dummy orig_r10
637 moveq 1, $r10
638 push $r10 ; frametype == 1, BUSFAULT frame type
640 move.d $sp, $r10 ; pt_regs argument to handle_mmu_bus_fault
642 jsr handle_mmu_bus_fault ; in arch/cris/arch-v10/mm/fault.c
644 ;; now we need to return through the normal path, we cannot just
645 ;; do the RBFexit since we might have killed off the running
646 ;; process due to a SEGV, scheduled due to a page blocking or
647 ;; whatever.
649 moveq 0, $r9 ; busfault is equivalent to an irq
651 ba ret_from_intr
652 nop
654 ;; special handlers for breakpoint and NMI
655 hwbreakpoint:
656 push $dccr
657 di
658 push $r10
659 push $r11
660 move.d [hw_bp_trig_ptr],$r10
661 move $brp,$r11
662 move.d $r11,[$r10+]
663 move.d $r10,[hw_bp_trig_ptr]
664 1: pop $r11
665 pop $r10
666 pop $dccr
667 retb
668 nop
670 IRQ1_interrupt:
671 ;; this prologue MUST match the one in irq.h and the struct in ptregs.h!!!
672 move $brp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
673 push $srp
674 push $dccr
675 push $mof
676 di
677 subq 14*4, $sp
678 movem $r13, [$sp]
679 push $r10 ; push orig_r10
680 clear.d [$sp=$sp-4] ; frametype == 0, normal frame
682 move.d [R_IRQ_MASK0_RD], $r1 ; External NMI or watchdog?
683 and.d 0x80000000, $r1
684 beq wdog
685 move.d $sp, $r10
686 jsr handle_nmi
687 setf m ; Enable NMI again
688 retb ; Return from NMI
689 nop
690 wdog:
691 #if defined(CONFIG_ETRAX_WATCHDOG) && !defined(CONFIG_SVINTO_SIM)
692 ;; Check if we're waiting for reset to happen, as signalled by
693 ;; hard_reset_now setting cause_of_death to a magic value. If so, just
694 ;; get stuck until reset happens.
695 .comm cause_of_death, 4 ;; Don't declare this anywhere.
696 move.d [cause_of_death], $r10
697 cmp.d 0xbedead, $r10
698 _killed_by_death:
699 beq _killed_by_death
700 nop
702 ;; We'll see this in ksymoops dumps.
703 Watchdog_bite:
705 #ifdef CONFIG_ETRAX_WATCHDOG_NICE_DOGGY
706 ;; We just restart the watchdog here to be sure we dont get
707 ;; hit while printing the watchdogmsg below
708 ;; This restart is compatible with the rest of the C-code, so
709 ;; the C-code can keep restarting the watchdog after this point.
710 ;; The non-NICE_DOGGY code below though, disables the possibility
711 ;; to restart since it changes the watchdog key, to avoid any
712 ;; buggy loops etc. keeping the watchdog alive after this.
713 jsr reset_watchdog
714 #else
716 ;; We need to extend the 3.3ms after the NMI at watchdog bite, so we have
717 ;; time for an oops-dump over a 115k2 serial wire. Another 100ms should do.
719 ;; Change the watchdog key to an arbitrary 3-bit value and restart the
720 ;; watchdog.
721 #define WD_INIT 2
722 moveq IO_FIELD (R_WATCHDOG, key, WD_INIT), $r10
723 move.d R_WATCHDOG, $r11
725 move.d $r10, [$r11]
726 moveq IO_FIELD (R_WATCHDOG, key, \
727 IO_EXTRACT (R_WATCHDOG, key, \
728 IO_MASK (R_WATCHDOG, key)) \
729 ^ WD_INIT) \
730 | IO_STATE (R_WATCHDOG, enable, start), $r10
731 move.d $r10, [$r11]
733 #endif
735 ;; Note that we don't do "setf m" here (or after two necessary NOPs),
736 ;; since *not* doing that saves us from re-entrancy checks. We don't want
737 ;; to get here again due to possible subsequent NMIs; we want the watchdog
738 ;; to reset us.
740 move.d _watchdogmsg,$r10
741 jsr printk
743 move.d $sp, $r10
744 jsr watchdog_bite_hook
746 ;; This nop is here so we see the "Watchdog_bite" label in ksymoops dumps
747 ;; rather than "spurious_interrupt".
748 nop
749 ;; At this point we drop down into spurious_interrupt, which will do a
750 ;; hard reset.
752 .section .rodata,"a"
753 _watchdogmsg:
754 .ascii "Oops: bitten by watchdog\n\0"
755 .previous
757 #endif /* CONFIG_ETRAX_WATCHDOG and not CONFIG_SVINTO_SIM */
759 spurious_interrupt:
760 di
761 jump hard_reset_now
763 ;; this handles the case when multiple interrupts arrive at the same time
764 ;; we jump to the first set interrupt bit in a priority fashion
765 ;; the hardware will call the unserved interrupts after the handler finishes
767 multiple_interrupt:
768 ;; this prologue MUST match the one in irq.h and the struct in ptregs.h!!!
769 move $irp,[$sp=$sp-16]; instruction pointer and room for a fake SBFS frame
770 push $srp
771 push $dccr
772 push $mof
773 di
774 subq 14*4, $sp
775 movem $r13, [$sp]
776 push $r10 ; push orig_r10
777 clear.d [$sp=$sp-4] ; frametype == 0, normal frame
779 moveq 2, $r2 ; first bit we care about is the timer0 irq
780 move.d [R_VECT_MASK_RD], $r0; read the irq bits that triggered the multiple irq
781 move.d $r0, [R_VECT_MASK_CLR] ; Block all active IRQs
782 1:
783 btst $r2, $r0 ; check for the irq given by bit r2
784 bpl 2f
785 move.d $r2, $r10 ; First argument to do_IRQ
786 move.d $sp, $r11 ; second argument to do_IRQ
787 jsr do_IRQ
788 2:
789 addq 1, $r2 ; next vector bit
790 cmp.b 32, $r2
791 bne 1b ; process all irq's up to and including number 31
792 moveq 0, $r9 ; make ret_from_intr realise we came from an ir
794 move.d $r0, [R_VECT_MASK_SET] ; Unblock all the IRQs
795 jump ret_from_intr
797 do_sigtrap:
798 ;;
799 ;; SIGTRAP the process that executed the break instruction.
800 ;; Make a frame that Rexit in entry.S expects.
801 ;;
802 move $brp, [$sp=$sp-16] ; Push BRP while faking a cpu status record.
803 push $srp ; Push subroutine return pointer.
804 push $dccr ; Push condition codes.
805 push $mof ; Push multiply overflow reg.
806 di ; Need to disable irq's at this point.
807 subq 14*4, $sp ; Make room for r0-r13.
808 movem $r13, [$sp] ; Push the r0-r13 registers.
809 push $r10 ; Push orig_r10.
810 clear.d [$sp=$sp-4] ; Frametype - this is a normal stackframe.
812 movs.w -8192,$r9 ; THREAD_SIZE == 8192
813 and.d $sp, $r9
814 move.d [$r9+TI_task], $r10
815 move.d [$r10+TASK_pid], $r10 ; current->pid as arg1.
816 moveq 5, $r11 ; SIGTRAP as arg2.
817 jsr sys_kill
818 jump ret_from_intr ; Use the return routine for interrupts.
820 gdb_handle_breakpoint:
821 push $dccr
822 push $r0
823 #ifdef CONFIG_ETRAX_KGDB
824 move $dccr, $r0 ; U-flag not affected by previous insns.
825 btstq 8, $r0 ; Test the U-flag.
826 bmi _ugdb_handle_breakpoint ; Go to user mode debugging.
827 nop ; Empty delay slot (cannot pop r0 here).
828 pop $r0 ; Restore r0.
829 ba kgdb_handle_breakpoint ; Go to kernel debugging.
830 pop $dccr ; Restore dccr in delay slot.
831 #endif
833 _ugdb_handle_breakpoint:
834 move $brp, $r0 ; Use r0 temporarily for calculation.
835 subq 2, $r0 ; Set to address of previous instruction.
836 move $r0, $brp
837 pop $r0 ; Restore r0.
838 ba do_sigtrap ; SIGTRAP the offending process.
839 pop $dccr ; Restore dccr in delay slot.
841 .data
843 hw_bp_trigs:
844 .space 64*4
845 hw_bp_trig_ptr:
846 .dword hw_bp_trigs
848 .section .rodata,"a"
849 sys_call_table:
850 .long sys_restart_syscall /* 0 - old "setup()" system call, used for restarting */
851 .long sys_exit
852 .long sys_fork
853 .long sys_read
854 .long sys_write
855 .long sys_open /* 5 */
856 .long sys_close
857 .long sys_waitpid
858 .long sys_creat
859 .long sys_link
860 .long sys_unlink /* 10 */
861 .long sys_execve
862 .long sys_chdir
863 .long sys_time
864 .long sys_mknod
865 .long sys_chmod /* 15 */
866 .long sys_lchown16
867 .long sys_ni_syscall /* old break syscall holder */
868 .long sys_stat
869 .long sys_lseek
870 .long sys_getpid /* 20 */
871 .long sys_mount
872 .long sys_oldumount
873 .long sys_setuid16
874 .long sys_getuid16
875 .long sys_stime /* 25 */
876 .long sys_ptrace
877 .long sys_alarm
878 .long sys_fstat
879 .long sys_pause
880 .long sys_utime /* 30 */
881 .long sys_ni_syscall /* old stty syscall holder */
882 .long sys_ni_syscall /* old gtty syscall holder */
883 .long sys_access
884 .long sys_nice
885 .long sys_ni_syscall /* 35 old ftime syscall holder */
886 .long sys_sync
887 .long sys_kill
888 .long sys_rename
889 .long sys_mkdir
890 .long sys_rmdir /* 40 */
891 .long sys_dup
892 .long sys_pipe
893 .long sys_times
894 .long sys_ni_syscall /* old prof syscall holder */
895 .long sys_brk /* 45 */
896 .long sys_setgid16
897 .long sys_getgid16
898 .long sys_signal
899 .long sys_geteuid16
900 .long sys_getegid16 /* 50 */
901 .long sys_acct
902 .long sys_umount /* recycled never used phys( */
903 .long sys_ni_syscall /* old lock syscall holder */
904 .long sys_ioctl
905 .long sys_fcntl /* 55 */
906 .long sys_ni_syscall /* old mpx syscall holder */
907 .long sys_setpgid
908 .long sys_ni_syscall /* old ulimit syscall holder */
909 .long sys_ni_syscall /* old sys_olduname holder */
910 .long sys_umask /* 60 */
911 .long sys_chroot
912 .long sys_ustat
913 .long sys_dup2
914 .long sys_getppid
915 .long sys_getpgrp /* 65 */
916 .long sys_setsid
917 .long sys_sigaction
918 .long sys_sgetmask
919 .long sys_ssetmask
920 .long sys_setreuid16 /* 70 */
921 .long sys_setregid16
922 .long sys_sigsuspend
923 .long sys_sigpending
924 .long sys_sethostname
925 .long sys_setrlimit /* 75 */
926 .long sys_old_getrlimit
927 .long sys_getrusage
928 .long sys_gettimeofday
929 .long sys_settimeofday
930 .long sys_getgroups16 /* 80 */
931 .long sys_setgroups16
932 .long sys_select /* was old_select in Linux/E100 */
933 .long sys_symlink
934 .long sys_lstat
935 .long sys_readlink /* 85 */
936 .long sys_uselib
937 .long sys_swapon
938 .long sys_reboot
939 .long old_readdir
940 .long old_mmap /* 90 */
941 .long sys_munmap
942 .long sys_truncate
943 .long sys_ftruncate
944 .long sys_fchmod
945 .long sys_fchown16 /* 95 */
946 .long sys_getpriority
947 .long sys_setpriority
948 .long sys_ni_syscall /* old profil syscall holder */
949 .long sys_statfs
950 .long sys_fstatfs /* 100 */
951 .long sys_ni_syscall /* sys_ioperm in i386 */
952 .long sys_socketcall
953 .long sys_syslog
954 .long sys_setitimer
955 .long sys_getitimer /* 105 */
956 .long sys_newstat
957 .long sys_newlstat
958 .long sys_newfstat
959 .long sys_ni_syscall /* old sys_uname holder */
960 .long sys_ni_syscall /* sys_iopl in i386 */
961 .long sys_vhangup
962 .long sys_ni_syscall /* old "idle" system call */
963 .long sys_ni_syscall /* vm86old in i386 */
964 .long sys_wait4
965 .long sys_swapoff /* 115 */
966 .long sys_sysinfo
967 .long sys_ipc
968 .long sys_fsync
969 .long sys_sigreturn
970 .long sys_clone /* 120 */
971 .long sys_setdomainname
972 .long sys_newuname
973 .long sys_ni_syscall /* sys_modify_ldt */
974 .long sys_adjtimex
975 .long sys_mprotect /* 125 */
976 .long sys_sigprocmask
977 .long sys_ni_syscall /* old "create_module" */
978 .long sys_init_module
979 .long sys_delete_module
980 .long sys_ni_syscall /* 130: old "get_kernel_syms" */
981 .long sys_quotactl
982 .long sys_getpgid
983 .long sys_fchdir
984 .long sys_bdflush
985 .long sys_sysfs /* 135 */
986 .long sys_personality
987 .long sys_ni_syscall /* for afs_syscall */
988 .long sys_setfsuid16
989 .long sys_setfsgid16
990 .long sys_llseek /* 140 */
991 .long sys_getdents
992 .long sys_select
993 .long sys_flock
994 .long sys_msync
995 .long sys_readv /* 145 */
996 .long sys_writev
997 .long sys_getsid
998 .long sys_fdatasync
999 .long sys_sysctl
1000 .long sys_mlock /* 150 */
1001 .long sys_munlock
1002 .long sys_mlockall
1003 .long sys_munlockall
1004 .long sys_sched_setparam
1005 .long sys_sched_getparam /* 155 */
1006 .long sys_sched_setscheduler
1007 .long sys_sched_getscheduler
1008 .long sys_sched_yield
1009 .long sys_sched_get_priority_max
1010 .long sys_sched_get_priority_min /* 160 */
1011 .long sys_sched_rr_get_interval
1012 .long sys_nanosleep
1013 .long sys_mremap
1014 .long sys_setresuid16
1015 .long sys_getresuid16 /* 165 */
1016 .long sys_ni_syscall /* sys_vm86 */
1017 .long sys_ni_syscall /* Old sys_query_module */
1018 .long sys_poll
1019 .long sys_nfsservctl
1020 .long sys_setresgid16 /* 170 */
1021 .long sys_getresgid16
1022 .long sys_prctl
1023 .long sys_rt_sigreturn
1024 .long sys_rt_sigaction
1025 .long sys_rt_sigprocmask /* 175 */
1026 .long sys_rt_sigpending
1027 .long sys_rt_sigtimedwait
1028 .long sys_rt_sigqueueinfo
1029 .long sys_rt_sigsuspend
1030 .long sys_pread64 /* 180 */
1031 .long sys_pwrite64
1032 .long sys_chown16
1033 .long sys_getcwd
1034 .long sys_capget
1035 .long sys_capset /* 185 */
1036 .long sys_sigaltstack
1037 .long sys_sendfile
1038 .long sys_ni_syscall /* streams1 */
1039 .long sys_ni_syscall /* streams2 */
1040 .long sys_vfork /* 190 */
1041 .long sys_getrlimit
1042 .long sys_mmap2
1043 .long sys_truncate64
1044 .long sys_ftruncate64
1045 .long sys_stat64 /* 195 */
1046 .long sys_lstat64
1047 .long sys_fstat64
1048 .long sys_lchown
1049 .long sys_getuid
1050 .long sys_getgid /* 200 */
1051 .long sys_geteuid
1052 .long sys_getegid
1053 .long sys_setreuid
1054 .long sys_setregid
1055 .long sys_getgroups /* 205 */
1056 .long sys_setgroups
1057 .long sys_fchown
1058 .long sys_setresuid
1059 .long sys_getresuid
1060 .long sys_setresgid /* 210 */
1061 .long sys_getresgid
1062 .long sys_chown
1063 .long sys_setuid
1064 .long sys_setgid
1065 .long sys_setfsuid /* 215 */
1066 .long sys_setfsgid
1067 .long sys_pivot_root
1068 .long sys_mincore
1069 .long sys_madvise
1070 .long sys_getdents64 /* 220 */
1071 .long sys_fcntl64
1072 .long sys_ni_syscall /* reserved for TUX */
1073 .long sys_ni_syscall
1074 .long sys_gettid
1075 .long sys_readahead /* 225 */
1076 .long sys_setxattr
1077 .long sys_lsetxattr
1078 .long sys_fsetxattr
1079 .long sys_getxattr
1080 .long sys_lgetxattr /* 230 */
1081 .long sys_fgetxattr
1082 .long sys_listxattr
1083 .long sys_llistxattr
1084 .long sys_flistxattr
1085 .long sys_removexattr /* 235 */
1086 .long sys_lremovexattr
1087 .long sys_fremovexattr
1088 .long sys_tkill
1089 .long sys_sendfile64
1090 .long sys_futex /* 240 */
1091 .long sys_sched_setaffinity
1092 .long sys_sched_getaffinity
1093 .long sys_ni_syscall /* sys_set_thread_area */
1094 .long sys_ni_syscall /* sys_get_thread_area */
1095 .long sys_io_setup /* 245 */
1096 .long sys_io_destroy
1097 .long sys_io_getevents
1098 .long sys_io_submit
1099 .long sys_io_cancel
1100 .long sys_fadvise64 /* 250 */
1101 .long sys_ni_syscall
1102 .long sys_exit_group
1103 .long sys_lookup_dcookie
1104 .long sys_epoll_create
1105 .long sys_epoll_ctl /* 255 */
1106 .long sys_epoll_wait
1107 .long sys_remap_file_pages
1108 .long sys_set_tid_address
1109 .long sys_timer_create
1110 .long sys_timer_settime /* 260 */
1111 .long sys_timer_gettime
1112 .long sys_timer_getoverrun
1113 .long sys_timer_delete
1114 .long sys_clock_settime
1115 .long sys_clock_gettime /* 265 */
1116 .long sys_clock_getres
1117 .long sys_clock_nanosleep
1118 .long sys_statfs64
1119 .long sys_fstatfs64
1120 .long sys_tgkill /* 270 */
1121 .long sys_utimes
1122 .long sys_fadvise64_64
1123 .long sys_ni_syscall /* sys_vserver */
1124 .long sys_ni_syscall /* sys_mbind */
1125 .long sys_ni_syscall /* 275 sys_get_mempolicy */
1126 .long sys_ni_syscall /* sys_set_mempolicy */
1127 .long sys_mq_open
1128 .long sys_mq_unlink
1129 .long sys_mq_timedsend
1130 .long sys_mq_timedreceive /* 280 */
1131 .long sys_mq_notify
1132 .long sys_mq_getsetattr
1133 .long sys_ni_syscall /* reserved for kexec */
1134 .long sys_waitid
1135 .long sys_ni_syscall /* 285 */ /* available */
1136 .long sys_add_key
1137 .long sys_request_key
1138 .long sys_keyctl
1140 /*
1141 * NOTE!! This doesn't have to be exact - we just have
1142 * to make sure we have _enough_ of the "sys_ni_syscall"
1143 * entries. Don't panic if you notice that this hasn't
1144 * been shrunk every time we add a new system call.
1145 */
1147 .rept NR_syscalls-(.-sys_call_table)/4
1148 .long sys_ni_syscall
1149 .endr