1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
|
/*
* Copyright (C) 2007-2009 Michal Simek <monstr@monstr.eu>
* Copyright (C) 2007-2009 PetaLogix
* Copyright (C) 2006 Atmark Techno, Inc.
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/linkage.h>
#include <asm/thread_info.h>
#include <linux/errno.h>
#include <asm/entry.h>
#include <asm/asm-offsets.h>
#include <asm/registers.h>
#include <asm/unistd.h>
#include <asm/percpu.h>
#include <asm/signal.h>
#if CONFIG_XILINX_MICROBLAZE0_USE_MSR_INSTR
.macro disable_irq
msrclr r0, MSR_IE
.endm
.macro enable_irq
msrset r0, MSR_IE
.endm
.macro clear_bip
msrclr r0, MSR_BIP
.endm
#else
.macro disable_irq
mfs r11, rmsr
andi r11, r11, ~MSR_IE
mts rmsr, r11
.endm
.macro enable_irq
mfs r11, rmsr
ori r11, r11, MSR_IE
mts rmsr, r11
.endm
.macro clear_bip
mfs r11, rmsr
andi r11, r11, ~MSR_BIP
mts rmsr, r11
.endm
#endif
ENTRY(_interrupt)
swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
lwi r11, r0, PER_CPU(KM) /* load mode indicator */
beqid r11, 1f
nop
brid 2f /* jump over */
addik r1, r1, (-PT_SIZE) /* room for pt_regs (delay slot) */
1: /* switch to kernel stack */
lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
lwi r1, r1, TS_THREAD_INFO /* get the thread info */
/* calculate kernel stack pointer */
addik r1, r1, THREAD_SIZE - PT_SIZE
2:
swi r11, r1, PT_MODE /* store the mode */
lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
swi r2, r1, PT_R2
swi r3, r1, PT_R3
swi r4, r1, PT_R4
swi r5, r1, PT_R5
swi r6, r1, PT_R6
swi r7, r1, PT_R7
swi r8, r1, PT_R8
swi r9, r1, PT_R9
swi r10, r1, PT_R10
swi r11, r1, PT_R11
swi r12, r1, PT_R12
swi r13, r1, PT_R13
swi r14, r1, PT_R14
swi r14, r1, PT_PC
swi r15, r1, PT_R15
swi r16, r1, PT_R16
swi r17, r1, PT_R17
swi r18, r1, PT_R18
swi r19, r1, PT_R19
swi r20, r1, PT_R20
swi r21, r1, PT_R21
swi r22, r1, PT_R22
swi r23, r1, PT_R23
swi r24, r1, PT_R24
swi r25, r1, PT_R25
swi r26, r1, PT_R26
swi r27, r1, PT_R27
swi r28, r1, PT_R28
swi r29, r1, PT_R29
swi r30, r1, PT_R30
swi r31, r1, PT_R31
/* special purpose registers */
mfs r11, rmsr
swi r11, r1, PT_MSR
mfs r11, rear
swi r11, r1, PT_EAR
mfs r11, resr
swi r11, r1, PT_ESR
mfs r11, rfsr
swi r11, r1, PT_FSR
/* reload original stack pointer and save it */
lwi r11, r0, PER_CPU(ENTRY_SP)
swi r11, r1, PT_R1
/* update mode indicator we are in kernel mode */
addik r11, r0, 1
swi r11, r0, PER_CPU(KM)
/* restore r31 */
lwi r31, r0, PER_CPU(CURRENT_SAVE)
/* prepare the link register, the argument and jump */
addik r15, r0, ret_from_intr - 8
addk r6, r0, r15
braid do_IRQ
add r5, r0, r1
ret_from_intr:
lwi r11, r1, PT_MODE
bneid r11, no_intr_resched
lwi r6, r31, TS_THREAD_INFO /* get thread info */
lwi r19, r6, TI_FLAGS /* get flags in thread info */
/* do an extra work if any bits are set */
andi r11, r19, _TIF_NEED_RESCHED
beqi r11, 1f
bralid r15, schedule
nop
1: andi r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME
beqid r11, no_intr_resched
addk r5, r1, r0
bralid r15, do_notify_resume
addk r6, r0, r0
no_intr_resched:
/* Disable interrupts, we are now committed to the state restore */
disable_irq
/* save mode indicator */
lwi r11, r1, PT_MODE
swi r11, r0, PER_CPU(KM)
/* save r31 */
swi r31, r0, PER_CPU(CURRENT_SAVE)
restore_context:
/* special purpose registers */
lwi r11, r1, PT_FSR
mts rfsr, r11
lwi r11, r1, PT_ESR
mts resr, r11
lwi r11, r1, PT_EAR
mts rear, r11
lwi r11, r1, PT_MSR
mts rmsr, r11
lwi r31, r1, PT_R31
lwi r30, r1, PT_R30
lwi r29, r1, PT_R29
lwi r28, r1, PT_R28
lwi r27, r1, PT_R27
lwi r26, r1, PT_R26
lwi r25, r1, PT_R25
lwi r24, r1, PT_R24
lwi r23, r1, PT_R23
lwi r22, r1, PT_R22
lwi r21, r1, PT_R21
lwi r20, r1, PT_R20
lwi r19, r1, PT_R19
lwi r18, r1, PT_R18
lwi r17, r1, PT_R17
lwi r16, r1, PT_R16
lwi r15, r1, PT_R15
lwi r14, r1, PT_PC
lwi r13, r1, PT_R13
lwi r12, r1, PT_R12
lwi r11, r1, PT_R11
lwi r10, r1, PT_R10
lwi r9, r1, PT_R9
lwi r8, r1, PT_R8
lwi r7, r1, PT_R7
lwi r6, r1, PT_R6
lwi r5, r1, PT_R5
lwi r4, r1, PT_R4
lwi r3, r1, PT_R3
lwi r2, r1, PT_R2
lwi r1, r1, PT_R1
rtid r14, 0
nop
ENTRY(_reset)
brai 0;
ENTRY(_user_exception)
swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
lwi r11, r0, PER_CPU(KM) /* load mode indicator */
beqid r11, 1f /* Already in kernel mode? */
nop
brid 2f /* jump over */
addik r1, r1, (-PT_SIZE) /* Room for pt_regs (delay slot) */
1: /* Switch to kernel stack */
lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
lwi r1, r1, TS_THREAD_INFO /* get the thread info */
/* calculate kernel stack pointer */
addik r1, r1, THREAD_SIZE - PT_SIZE
2:
swi r11, r1, PT_MODE /* store the mode */
lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
/* save them on stack */
swi r2, r1, PT_R2
swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
swi r5, r1, PT_R5
swi r6, r1, PT_R6
swi r7, r1, PT_R7
swi r8, r1, PT_R8
swi r9, r1, PT_R9
swi r10, r1, PT_R10
swi r11, r1, PT_R11
/* r12: _always_ in clobber list; see unistd.h */
swi r12, r1, PT_R12
swi r13, r1, PT_R13
/* r14: _always_ in clobber list; see unistd.h */
swi r14, r1, PT_R14
/* but we want to return to the next inst. */
addik r14, r14, 0x4
swi r14, r1, PT_PC /* increment by 4 and store in pc */
swi r15, r1, PT_R15
swi r16, r1, PT_R16
swi r17, r1, PT_R17
swi r18, r1, PT_R18
swi r19, r1, PT_R19
swi r20, r1, PT_R20
swi r21, r1, PT_R21
swi r22, r1, PT_R22
swi r23, r1, PT_R23
swi r24, r1, PT_R24
swi r25, r1, PT_R25
swi r26, r1, PT_R26
swi r27, r1, PT_R27
swi r28, r1, PT_R28
swi r29, r1, PT_R29
swi r30, r1, PT_R30
swi r31, r1, PT_R31
disable_irq
nop /* make sure IE bit is in effect */
clear_bip /* once IE is in effect it is safe to clear BIP */
nop
/* special purpose registers */
mfs r11, rmsr
swi r11, r1, PT_MSR
mfs r11, rear
swi r11, r1, PT_EAR
mfs r11, resr
swi r11, r1, PT_ESR
mfs r11, rfsr
swi r11, r1, PT_FSR
/* reload original stack pointer and save it */
lwi r11, r0, PER_CPU(ENTRY_SP)
swi r11, r1, PT_R1
/* update mode indicator we are in kernel mode */
addik r11, r0, 1
swi r11, r0, PER_CPU(KM)
/* restore r31 */
lwi r31, r0, PER_CPU(CURRENT_SAVE)
/* re-enable interrupts now we are in kernel mode */
enable_irq
/* See if the system call number is valid. */
addi r11, r12, -__NR_syscalls
bgei r11, 1f /* return to user if not valid */
/* Figure out which function to use for this system call. */
/* Note Microblaze barrel shift is optional, so don't rely on it */
add r12, r12, r12 /* convert num -> ptr */
add r12, r12, r12
lwi r12, r12, sys_call_table /* Get function pointer */
addik r15, r0, ret_to_user-8 /* set return address */
bra r12 /* Make the system call. */
bri 0 /* won't reach here */
1:
brid ret_to_user /* jump to syscall epilogue */
addi r3, r0, -ENOSYS /* set errno in delay slot */
/*
* Debug traps are like a system call, but entered via brki r14, 0x60
* All we need to do is send the SIGTRAP signal to current, ptrace and
* do_notify_resume will handle the rest
*/
ENTRY(_debug_exception)
swi r1, r0, PER_CPU(ENTRY_SP) /* save the current sp */
lwi r1, r0, PER_CPU(CURRENT_SAVE) /* get the saved current */
lwi r1, r1, TS_THREAD_INFO /* get the thread info */
addik r1, r1, THREAD_SIZE - PT_SIZE /* get the kernel stack */
swi r11, r0, PER_CPU(R11_SAVE) /* temporarily save r11 */
lwi r11, r0, PER_CPU(KM) /* load mode indicator */
//save_context:
swi r11, r1, PT_MODE /* store the mode */
lwi r11, r0, PER_CPU(R11_SAVE) /* reload r11 */
/* save them on stack */
swi r2, r1, PT_R2
swi r3, r1, PT_R3 /* r3: _always_ in clobber list; see unistd.h */
swi r4, r1, PT_R4 /* r4: _always_ in clobber list; see unistd.h */
swi r5, r1, PT_R5
swi r6, r1, PT_R6
swi r7, r1, PT_R7
swi r8, r1, PT_R8
swi r9, r1, PT_R9
swi r10, r1, PT_R10
swi r11, r1, PT_R11
/* r12: _always_ in clobber list; see unistd.h */
swi r12, r1, PT_R12
swi r13, r1, PT_R13
/* r14: _always_ in clobber list; see unistd.h */
swi r14, r1, PT_R14
swi r14, r1, PT_PC /* Will return to interrupted instruction */
swi r15, r1, PT_R15
swi r16, r1, PT_R16
swi r17, r1, PT_R17
swi r18, r1, PT_R18
swi r19, r1, PT_R19
swi r20, r1, PT_R20
swi r21, r1, PT_R21
swi r22, r1, PT_R22
swi r23, r1, PT_R23
swi r24, r1, PT_R24
swi r25, r1, PT_R25
swi r26, r1, PT_R26
swi r27, r1, PT_R27
swi r28, r1, PT_R28
swi r29, r1, PT_R29
swi r30, r1, PT_R30
swi r31, r1, PT_R31
disable_irq
nop /* make sure IE bit is in effect */
clear_bip /* once IE is in effect it is safe to clear BIP */
nop
/* special purpose registers */
mfs r11, rmsr
swi r11, r1, PT_MSR
mfs r11, rear
swi r11, r1, PT_EAR
mfs r11, resr
swi r11, r1, PT_ESR
mfs r11, rfsr
swi r11, r1, PT_FSR
/* reload original stack pointer and save it */
lwi r11, r0, PER_CPU(ENTRY_SP)
swi r11, r1, PT_R1
/* update mode indicator we are in kernel mode */
addik r11, r0, 1
swi r11, r0, PER_CPU(KM)
/* restore r31 */
lwi r31, r0, PER_CPU(CURRENT_SAVE)
/* re-enable interrupts now we are in kernel mode */
enable_irq
addi r5, r0, SIGTRAP /* sending the trap signal */
add r6, r0, r31 /* to current */
bralid r15, send_sig
add r7, r0, r0 /* 3rd param zero */
/* Restore r3/r4 to work around how ret_to_user works */
lwi r3, r1, PT_R3
lwi r4, r1, PT_R4
bri ret_to_user
ENTRY(_break)
bri 0
/* struct task_struct *_switch_to(struct thread_info *prev,
struct thread_info *next); */
ENTRY(_switch_to)
/* prepare return value */
addk r3, r0, r31
/* save registers in cpu_context */
/* use r11 and r12, volatile registers, as temp register */
addik r11, r5, TI_CPU_CONTEXT
swi r1, r11, CC_R1
swi r2, r11, CC_R2
/* skip volatile registers.
* they are saved on stack when we jumped to _switch_to() */
/* dedicated registers */
swi r13, r11, CC_R13
swi r14, r11, CC_R14
swi r15, r11, CC_R15
swi r16, r11, CC_R16
swi r17, r11, CC_R17
swi r18, r11, CC_R18
/* save non-volatile registers */
swi r19, r11, CC_R19
swi r20, r11, CC_R20
swi r21, r11, CC_R21
swi r22, r11, CC_R22
swi r23, r11, CC_R23
swi r24, r11, CC_R24
swi r25, r11, CC_R25
swi r26, r11, CC_R26
swi r27, r11, CC_R27
swi r28, r11, CC_R28
swi r29, r11, CC_R29
swi r30, r11, CC_R30
/* special purpose registers */
mfs r12, rmsr
swi r12, r11, CC_MSR
mfs r12, rear
swi r12, r11, CC_EAR
mfs r12, resr
swi r12, r11, CC_ESR
mfs r12, rfsr
swi r12, r11, CC_FSR
/* update r31, the current */
lwi r31, r6, TI_TASK
swi r31, r0, PER_CPU(CURRENT_SAVE)
/* get new process' cpu context and restore */
addik r11, r6, TI_CPU_CONTEXT
/* special purpose registers */
lwi r12, r11, CC_FSR
mts rfsr, r12
lwi r12, r11, CC_ESR
mts resr, r12
lwi r12, r11, CC_EAR
mts rear, r12
lwi r12, r11, CC_MSR
mts rmsr, r12
/* non-volatile registers */
lwi r30, r11, CC_R30
lwi r29, r11, CC_R29
lwi r28, r11, CC_R28
lwi r27, r11, CC_R27
lwi r26, r11, CC_R26
lwi r25, r11, CC_R25
lwi r24, r11, CC_R24
lwi r23, r11, CC_R23
lwi r22, r11, CC_R22
lwi r21, r11, CC_R21
lwi r20, r11, CC_R20
lwi r19, r11, CC_R19
/* dedicated registers */
lwi r18, r11, CC_R18
lwi r17, r11, CC_R17
lwi r16, r11, CC_R16
lwi r15, r11, CC_R15
lwi r14, r11, CC_R14
lwi r13, r11, CC_R13
/* skip volatile registers */
lwi r2, r11, CC_R2
lwi r1, r11, CC_R1
rtsd r15, 8
nop
ENTRY(ret_from_fork)
addk r5, r0, r3
addk r6, r0, r1
brlid r15, schedule_tail
nop
swi r31, r1, PT_R31 /* save r31 in user context. */
/* will soon be restored to r31 in ret_to_user */
addk r3, r0, r0
brid ret_to_user
nop
ENTRY(ret_from_kernel_thread)
brlid r15, schedule_tail
addk r5, r0, r3
brald r15, r20
addk r5, r0, r19
brid ret_to_user
addk r3, r0, r0
work_pending:
enable_irq
andi r11, r19, _TIF_NEED_RESCHED
beqi r11, 1f
bralid r15, schedule
nop
1: andi r11, r19, _TIF_SIGPENDING | _TIF_NOTIFY_RESUME
beqi r11, no_work_pending
addk r5, r1, r0
bralid r15, do_notify_resume
addik r6, r0, 1
bri no_work_pending
ENTRY(ret_to_user)
disable_irq
swi r4, r1, PT_R4 /* return val */
swi r3, r1, PT_R3 /* return val */
lwi r6, r31, TS_THREAD_INFO /* get thread info */
lwi r19, r6, TI_FLAGS /* get flags in thread info */
bnei r19, work_pending /* do an extra work if any bits are set */
no_work_pending:
disable_irq
/* save r31 */
swi r31, r0, PER_CPU(CURRENT_SAVE)
/* save mode indicator */
lwi r18, r1, PT_MODE
swi r18, r0, PER_CPU(KM)
//restore_context:
/* special purpose registers */
lwi r18, r1, PT_FSR
mts rfsr, r18
lwi r18, r1, PT_ESR
mts resr, r18
lwi r18, r1, PT_EAR
mts rear, r18
lwi r18, r1, PT_MSR
mts rmsr, r18
lwi r31, r1, PT_R31
lwi r30, r1, PT_R30
lwi r29, r1, PT_R29
lwi r28, r1, PT_R28
lwi r27, r1, PT_R27
lwi r26, r1, PT_R26
lwi r25, r1, PT_R25
lwi r24, r1, PT_R24
lwi r23, r1, PT_R23
lwi r22, r1, PT_R22
lwi r21, r1, PT_R21
lwi r20, r1, PT_R20
lwi r19, r1, PT_R19
lwi r18, r1, PT_R18
lwi r17, r1, PT_R17
lwi r16, r1, PT_R16
lwi r15, r1, PT_R15
lwi r14, r1, PT_PC
lwi r13, r1, PT_R13
lwi r12, r1, PT_R12
lwi r11, r1, PT_R11
lwi r10, r1, PT_R10
lwi r9, r1, PT_R9
lwi r8, r1, PT_R8
lwi r7, r1, PT_R7
lwi r6, r1, PT_R6
lwi r5, r1, PT_R5
lwi r4, r1, PT_R4 /* return val */
lwi r3, r1, PT_R3 /* return val */
lwi r2, r1, PT_R2
lwi r1, r1, PT_R1
rtid r14, 0
nop
sys_rt_sigreturn_wrapper:
brid sys_rt_sigreturn
addk r5, r1, r0
/* Interrupt vector table */
.section .init.ivt, "ax"
.org 0x0
brai _reset
brai _user_exception
brai _interrupt
brai _break
brai _hw_exception_handler
.org 0x60
brai _debug_exception
.section .rodata,"a"
#include "syscall_table.S"
syscall_table_size=(.-sys_call_table)
type_SYSCALL:
.ascii "SYSCALL\0"
type_IRQ:
.ascii "IRQ\0"
type_IRQ_PREEMPT:
.ascii "IRQ (PREEMPTED)\0"
type_SYSCALL_PREEMPT:
.ascii " SYSCALL (PREEMPTED)\0"
/*
* Trap decoding for stack unwinder
* Tuples are (start addr, end addr, string)
* If return address lies on [start addr, end addr],
* unwinder displays 'string'
*/
.align 4
.global microblaze_trap_handlers
microblaze_trap_handlers:
/* Exact matches come first */
.word ret_to_user ; .word ret_to_user ; .word type_SYSCALL
.word ret_from_intr; .word ret_from_intr ; .word type_IRQ
/* Fuzzy matches go here */
.word ret_from_intr; .word no_intr_resched; .word type_IRQ_PREEMPT
.word work_pending ; .word no_work_pending; .word type_SYSCALL_PREEMPT
/* End of table */
.word 0 ; .word 0 ; .word 0
|
