| blob | b350dd279ed21f914caf7c417d6cc7f9a092e33e |
1 /*
2 * Copyright (C) 2004 Axis Communications AB
3 *
4 * Code for handling break 8, hardware breakpoint, single step, and serial
5 * port exceptions for kernel debugging purposes.
6 */
8 #include <linux/config.h>
9 #include <asm/arch/hwregs/intr_vect.h>
11 ;; Exported functions.
12 .globl kgdb_handle_exception
14 kgdb_handle_exception:
16 ;; Create a register image of the caller.
17 ;;
18 ;; First of all, save the ACR on the stack since we need it for address calculations.
19 ;; We put it into the register struct later.
21 subq 4, $sp
22 move.d $acr, [$sp]
24 ;; Now we are free to use ACR all we want.
25 ;; If we were running this handler with interrupts on, we would have to be careful
26 ;; to save and restore CCS manually, but since we aren't we treat it like every other
27 ;; register.
29 move.d reg, $acr
30 move.d $r0, [$acr] ; Save R0 (start of register struct)
31 addq 4, $acr
32 move.d $r1, [$acr] ; Save R1
33 addq 4, $acr
34 move.d $r2, [$acr] ; Save R2
35 addq 4, $acr
36 move.d $r3, [$acr] ; Save R3
37 addq 4, $acr
38 move.d $r4, [$acr] ; Save R4
39 addq 4, $acr
40 move.d $r5, [$acr] ; Save R5
41 addq 4, $acr
42 move.d $r6, [$acr] ; Save R6
43 addq 4, $acr
44 move.d $r7, [$acr] ; Save R7
45 addq 4, $acr
46 move.d $r8, [$acr] ; Save R8
47 addq 4, $acr
48 move.d $r9, [$acr] ; Save R9
49 addq 4, $acr
50 move.d $r10, [$acr] ; Save R10
51 addq 4, $acr
52 move.d $r11, [$acr] ; Save R11
53 addq 4, $acr
54 move.d $r12, [$acr] ; Save R12
55 addq 4, $acr
56 move.d $r13, [$acr] ; Save R13
57 addq 4, $acr
58 move.d $sp, [$acr] ; Save SP (R14)
59 addq 4, $acr
61 ;; The ACR register is already saved on the stack, so pop it from there.
62 move.d [$sp],$r0
63 move.d $r0, [$acr]
64 addq 4, $acr
66 move $bz, [$acr]
67 addq 1, $acr
68 move $vr, [$acr]
69 addq 1, $acr
70 move $pid, [$acr]
71 addq 4, $acr
72 move $srs, [$acr]
73 addq 1, $acr
74 move $wz, [$acr]
75 addq 2, $acr
76 move $exs, [$acr]
77 addq 4, $acr
78 move $eda, [$acr]
79 addq 4, $acr
80 move $mof, [$acr]
81 addq 4, $acr
82 move $dz, [$acr]
83 addq 4, $acr
84 move $ebp, [$acr]
85 addq 4, $acr
86 move $erp, [$acr]
87 addq 4, $acr
88 move $srp, [$acr]
89 addq 4, $acr
90 move $nrp, [$acr]
91 addq 4, $acr
92 move $ccs, [$acr]
93 addq 4, $acr
94 move $usp, [$acr]
95 addq 4, $acr
96 move $spc, [$acr]
97 addq 4, $acr
99 ;; Skip the pseudo-PC.
100 addq 4, $acr
102 ;; Save the support registers in bank 0 - 3.
103 clear.d $r1 ; Bank counter
104 move.d sreg, $acr
106 ;; Bank 0
107 move $r1, $srs
108 nop
109 nop
110 nop
111 move $s0, $r0
112 move.d $r0, [$acr]
113 addq 4, $acr
114 move $s1, $r0
115 move.d $r0, [$acr]
116 addq 4, $acr
117 move $s2, $r0
118 move.d $r0, [$acr]
119 addq 4, $acr
120 move $s3, $r0
121 move.d $r0, [$acr]
122 addq 4, $acr
123 move $s4, $r0
124 move.d $r0, [$acr]
125 addq 4, $acr
126 move $s5, $r0
127 move.d $r0, [$acr]
128 addq 4, $acr
129 move $s6, $r0
130 move.d $r0, [$acr]
131 addq 4, $acr
132 move $s7, $r0
133 move.d $r0, [$acr]
134 addq 4, $acr
135 move $s8, $r0
136 move.d $r0, [$acr]
137 addq 4, $acr
138 move $s9, $r0
139 move.d $r0, [$acr]
140 addq 4, $acr
141 move $s10, $r0
142 move.d $r0, [$acr]
143 addq 4, $acr
144 move $s11, $r0
145 move.d $r0, [$acr]
146 addq 4, $acr
147 move $s12, $r0
148 move.d $r0, [$acr]
149 addq 4, $acr
151 ;; Nothing in S13 - S15, bank 0
152 clear.d [$acr]
153 addq 4, $acr
154 clear.d [$acr]
155 addq 4, $acr
156 clear.d [$acr]
157 addq 4, $acr
159 ;; Bank 1 and bank 2 have the same layout, hence the loop.
160 addq 1, $r1
161 1:
162 move $r1, $srs
163 nop
164 nop
165 nop
166 move $s0, $r0
167 move.d $r0, [$acr]
168 addq 4, $acr
169 move $s1, $r0
170 move.d $r0, [$acr]
171 addq 4, $acr
172 move $s2, $r0
173 move.d $r0, [$acr]
174 addq 4, $acr
175 move $s3, $r0
176 move.d $r0, [$acr]
177 addq 4, $acr
178 move $s4, $r0
179 move.d $r0, [$acr]
180 addq 4, $acr
181 move $s5, $r0
182 move.d $r0, [$acr]
183 addq 4, $acr
184 move $s6, $r0
185 move.d $r0, [$acr]
186 addq 4, $acr
188 ;; Nothing in S7 - S15, bank 1 and 2
189 clear.d [$acr]
190 addq 4, $acr
191 clear.d [$acr]
192 addq 4, $acr
193 clear.d [$acr]
194 addq 4, $acr
195 clear.d [$acr]
196 addq 4, $acr
197 clear.d [$acr]
198 addq 4, $acr
199 clear.d [$acr]
200 addq 4, $acr
201 clear.d [$acr]
202 addq 4, $acr
203 clear.d [$acr]
204 addq 4, $acr
205 clear.d [$acr]
206 addq 4, $acr
208 addq 1, $r1
209 cmpq 3, $r1
210 bne 1b
211 nop
213 ;; Bank 3
214 move $r1, $srs
215 nop
216 nop
217 nop
218 move $s0, $r0
219 move.d $r0, [$acr]
220 addq 4, $acr
221 move $s1, $r0
222 move.d $r0, [$acr]
223 addq 4, $acr
224 move $s2, $r0
225 move.d $r0, [$acr]
226 addq 4, $acr
227 move $s3, $r0
228 move.d $r0, [$acr]
229 addq 4, $acr
230 move $s4, $r0
231 move.d $r0, [$acr]
232 addq 4, $acr
233 move $s5, $r0
234 move.d $r0, [$acr]
235 addq 4, $acr
236 move $s6, $r0
237 move.d $r0, [$acr]
238 addq 4, $acr
239 move $s7, $r0
240 move.d $r0, [$acr]
241 addq 4, $acr
242 move $s8, $r0
243 move.d $r0, [$acr]
244 addq 4, $acr
245 move $s9, $r0
246 move.d $r0, [$acr]
247 addq 4, $acr
248 move $s10, $r0
249 move.d $r0, [$acr]
250 addq 4, $acr
251 move $s11, $r0
252 move.d $r0, [$acr]
253 addq 4, $acr
254 move $s12, $r0
255 move.d $r0, [$acr]
256 addq 4, $acr
257 move $s13, $r0
258 move.d $r0, [$acr]
259 addq 4, $acr
260 move $s14, $r0
261 move.d $r0, [$acr]
262 addq 4, $acr
263 ;; Nothing in S15, bank 3
264 clear.d [$acr]
265 addq 4, $acr
267 ;; Check what got us here: get IDX field of EXS.
268 move $exs, $r10
269 and.d 0xff00, $r10
270 lsrq 8, $r10
271 #if defined(CONFIG_ETRAX_KGDB_PORT0)
272 cmp.d SER0_INTR_VECT, $r10 ; IRQ for serial port 0
273 beq sigint
274 nop
275 #elif defined(CONFIG_ETRAX_KGDB_PORT1)
276 cmp.d SER1_INTR_VECT, $r10 ; IRQ for serial port 1
277 beq sigint
278 nop
279 #elif defined(CONFIG_ETRAX_KGDB_PORT2)
280 cmp.d SER2_INTR_VECT, $r10 ; IRQ for serial port 2
281 beq sigint
282 nop
283 #elif defined(CONFIG_ETRAX_KGDB_PORT3)
284 cmp.d SER3_INTR_VECT, $r10 ; IRQ for serial port 3
285 beq sigint
286 nop
287 #endif
288 ;; Multiple interrupt must be due to serial break.
289 cmp.d 0x30, $r10 ; Multiple interrupt
290 beq sigint
291 nop
292 ;; Neither of those? Then it's a sigtrap.
293 ba handle_comm
294 moveq 5, $r10 ; Set SIGTRAP (delay slot)
296 sigint:
297 ;; Serial interrupt; get character
298 jsr getDebugChar
299 nop ; Delay slot
300 cmp.b 3, $r10 ; \003 (Ctrl-C)?
301 bne return ; No, get out of here
302 nop
303 moveq 2, $r10 ; Set SIGINT
305 ;;
306 ;; Handle the communication
307 ;;
308 handle_comm:
309 move.d internal_stack+1020, $sp ; Use the internal stack which grows upwards
310 jsr handle_exception ; Interactive routine
311 nop
313 ;;
314 ;; Return to the caller
315 ;;
316 return:
318 ;; First of all, write the support registers.
319 clear.d $r1 ; Bank counter
320 move.d sreg, $acr
322 ;; Bank 0
323 move $r1, $srs
324 nop
325 nop
326 nop
327 move.d [$acr], $r0
328 move $r0, $s0
329 addq 4, $acr
330 move.d [$acr], $r0
331 move $r0, $s1
332 addq 4, $acr
333 move.d [$acr], $r0
334 move $r0, $s2
335 addq 4, $acr
336 move.d [$acr], $r0
337 move $r0, $s3
338 addq 4, $acr
339 move.d [$acr], $r0
340 move $r0, $s4
341 addq 4, $acr
342 move.d [$acr], $r0
343 move $r0, $s5
344 addq 4, $acr
346 ;; Nothing in S6 - S7, bank 0.
347 addq 4, $acr
348 addq 4, $acr
350 move.d [$acr], $r0
351 move $r0, $s8
352 addq 4, $acr
353 move.d [$acr], $r0
354 move $r0, $s9
355 addq 4, $acr
356 move.d [$acr], $r0
357 move $r0, $s10
358 addq 4, $acr
359 move.d [$acr], $r0
360 move $r0, $s11
361 addq 4, $acr
362 move.d [$acr], $r0
363 move $r0, $s12
364 addq 4, $acr
366 ;; Nothing in S13 - S15, bank 0
367 addq 4, $acr
368 addq 4, $acr
369 addq 4, $acr
371 ;; Bank 1 and bank 2 have the same layout, hence the loop.
372 addq 1, $r1
373 2:
374 move $r1, $srs
375 nop
376 nop
377 nop
378 move.d [$acr], $r0
379 move $r0, $s0
380 addq 4, $acr
381 move.d [$acr], $r0
382 move $r0, $s1
383 addq 4, $acr
384 move.d [$acr], $r0
385 move $r0, $s2
386 addq 4, $acr
388 ;; S3 (MM_CAUSE) is read-only.
389 addq 4, $acr
391 move.d [$acr], $r0
392 move $r0, $s4
393 addq 4, $acr
395 ;; FIXME: Actually write S5/S6? (Affects MM_CAUSE.)
396 addq 4, $acr
397 addq 4, $acr
399 ;; Nothing in S7 - S15, bank 1 and 2
400 addq 4, $acr
401 addq 4, $acr
402 addq 4, $acr
403 addq 4, $acr
404 addq 4, $acr
405 addq 4, $acr
406 addq 4, $acr
407 addq 4, $acr
408 addq 4, $acr
410 addq 1, $r1
411 cmpq 3, $r1
412 bne 2b
413 nop
415 ;; Bank 3
416 move $r1, $srs
417 nop
418 nop
419 nop
420 move.d [$acr], $r0
421 move $r0, $s0
422 addq 4, $acr
423 move.d [$acr], $r0
424 move $r0, $s1
425 addq 4, $acr
426 move.d [$acr], $r0
427 move $r0, $s2
428 addq 4, $acr
429 move.d [$acr], $r0
430 move $r0, $s3
431 addq 4, $acr
432 move.d [$acr], $r0
433 move $r0, $s4
434 addq 4, $acr
435 move.d [$acr], $r0
436 move $r0, $s5
437 addq 4, $acr
438 move.d [$acr], $r0
439 move $r0, $s6
440 addq 4, $acr
441 move.d [$acr], $r0
442 move $r0, $s7
443 addq 4, $acr
444 move.d [$acr], $r0
445 move $r0, $s8
446 addq 4, $acr
447 move.d [$acr], $r0
448 move $r0, $s9
449 addq 4, $acr
450 move.d [$acr], $r0
451 move $r0, $s10
452 addq 4, $acr
453 move.d [$acr], $r0
454 move $r0, $s11
455 addq 4, $acr
456 move.d [$acr], $r0
457 move $r0, $s12
458 addq 4, $acr
459 move.d [$acr], $r0
460 move $r0, $s13
461 addq 4, $acr
462 move.d [$acr], $r0
463 move $r0, $s14
464 addq 4, $acr
466 ;; Nothing in S15, bank 3
467 addq 4, $acr
469 ;; Now, move on to the regular register restoration process.
471 move.d reg, $acr ; Reset ACR to point at the beginning of the register image
472 move.d [$acr], $r0 ; Restore R0
473 addq 4, $acr
474 move.d [$acr], $r1 ; Restore R1
475 addq 4, $acr
476 move.d [$acr], $r2 ; Restore R2
477 addq 4, $acr
478 move.d [$acr], $r3 ; Restore R3
479 addq 4, $acr
480 move.d [$acr], $r4 ; Restore R4
481 addq 4, $acr
482 move.d [$acr], $r5 ; Restore R5
483 addq 4, $acr
484 move.d [$acr], $r6 ; Restore R6
485 addq 4, $acr
486 move.d [$acr], $r7 ; Restore R7
487 addq 4, $acr
488 move.d [$acr], $r8 ; Restore R8
489 addq 4, $acr
490 move.d [$acr], $r9 ; Restore R9
491 addq 4, $acr
492 move.d [$acr], $r10 ; Restore R10
493 addq 4, $acr
494 move.d [$acr], $r11 ; Restore R11
495 addq 4, $acr
496 move.d [$acr], $r12 ; Restore R12
497 addq 4, $acr
498 move.d [$acr], $r13 ; Restore R13
500 ;;
501 ;; We restore all registers, even though some of them probably haven't changed.
502 ;;
504 addq 4, $acr
505 move.d [$acr], $sp ; Restore SP (R14)
507 ;; ACR cannot be restored just yet.
508 addq 8, $acr
510 ;; Skip BZ, VR.
511 addq 2, $acr
513 move [$acr], $pid ; Restore PID
514 addq 4, $acr
515 move [$acr], $srs ; Restore SRS
516 nop
517 nop
518 nop
519 addq 1, $acr
521 ;; Skip WZ.
522 addq 2, $acr
524 move [$acr], $exs ; Restore EXS.
525 addq 4, $acr
526 move [$acr], $eda ; Restore EDA.
527 addq 4, $acr
528 move [$acr], $mof ; Restore MOF.
530 ;; Skip DZ.
531 addq 8, $acr
533 move [$acr], $ebp ; Restore EBP.
534 addq 4, $acr
535 move [$acr], $erp ; Restore ERP.
536 addq 4, $acr
537 move [$acr], $srp ; Restore SRP.
538 addq 4, $acr
539 move [$acr], $nrp ; Restore NRP.
540 addq 4, $acr
541 move [$acr], $ccs ; Restore CCS like an ordinary register.
542 addq 4, $acr
543 move [$acr], $usp ; Restore USP
544 addq 4, $acr
545 move [$acr], $spc ; Restore SPC
546 ; No restoration of pseudo-PC of course.
548 move.d reg, $acr ; Reset ACR to point at the beginning of the register image
549 add.d 15*4, $acr
550 move.d [$acr], $acr ; Finally, restore ACR.
551 rete ; Same as jump ERP
552 rfe ; Shifts CCS