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ef016f83 MF |
1 | /* Blackfin Core Event Controller (CEC) model. |
2 | ||
b811d2c2 | 3 | Copyright (C) 2010-2020 Free Software Foundation, Inc. |
ef016f83 MF |
4 | Contributed by Analog Devices, Inc. |
5 | ||
6 | This file is part of simulators. | |
7 | ||
8 | This program is free software; you can redistribute it and/or modify | |
9 | it under the terms of the GNU General Public License as published by | |
10 | the Free Software Foundation; either version 3 of the License, or | |
11 | (at your option) any later version. | |
12 | ||
13 | This program is distributed in the hope that it will be useful, | |
14 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
16 | GNU General Public License for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ | |
20 | ||
21 | #include "config.h" | |
22 | ||
23 | #include "sim-main.h" | |
24 | #include "devices.h" | |
25 | #include "dv-bfin_cec.h" | |
26 | #include "dv-bfin_evt.h" | |
27 | #include "dv-bfin_mmu.h" | |
28 | ||
29 | struct bfin_cec | |
30 | { | |
31 | bu32 base; | |
32 | SIM_CPU *cpu; | |
33 | struct hw *me; | |
34 | struct hw_event *pending; | |
35 | ||
36 | /* Order after here is important -- matches hardware MMR layout. */ | |
37 | bu32 evt_override, imask, ipend, ilat, iprio; | |
38 | }; | |
39 | #define mmr_base() offsetof(struct bfin_cec, evt_override) | |
40 | #define mmr_offset(mmr) (offsetof(struct bfin_cec, mmr) - mmr_base()) | |
41 | ||
990d19fd MF |
42 | static const char * const mmr_names[] = |
43 | { | |
ef016f83 MF |
44 | "EVT_OVERRIDE", "IMASK", "IPEND", "ILAT", "IPRIO", |
45 | }; | |
46 | #define mmr_name(off) mmr_names[(off) / 4] | |
47 | ||
48 | static void _cec_raise (SIM_CPU *, struct bfin_cec *, int); | |
49 | ||
50 | static void | |
51 | bfin_cec_hw_event_callback (struct hw *me, void *data) | |
52 | { | |
53 | struct bfin_cec *cec = data; | |
54 | hw_event_queue_deschedule (me, cec->pending); | |
55 | _cec_raise (cec->cpu, cec, -1); | |
56 | cec->pending = NULL; | |
57 | } | |
58 | static void | |
59 | bfin_cec_check_pending (struct hw *me, struct bfin_cec *cec) | |
60 | { | |
61 | if (cec->pending) | |
62 | return; | |
63 | cec->pending = hw_event_queue_schedule (me, 0, bfin_cec_hw_event_callback, cec); | |
64 | } | |
65 | static void | |
66 | _cec_check_pending (SIM_CPU *cpu, struct bfin_cec *cec) | |
67 | { | |
68 | bfin_cec_check_pending (cec->me, cec); | |
69 | } | |
70 | ||
71 | static void | |
72 | _cec_imask_write (struct bfin_cec *cec, bu32 value) | |
73 | { | |
74 | cec->imask = (value & IVG_MASKABLE_B) | (cec->imask & IVG_UNMASKABLE_B); | |
75 | } | |
76 | ||
77 | static unsigned | |
78 | bfin_cec_io_write_buffer (struct hw *me, const void *source, | |
79 | int space, address_word addr, unsigned nr_bytes) | |
80 | { | |
81 | struct bfin_cec *cec = hw_data (me); | |
82 | bu32 mmr_off; | |
83 | bu32 value; | |
84 | ||
466b619e MF |
85 | /* Invalid access mode is higher priority than missing register. */ |
86 | if (!dv_bfin_mmr_require_32 (me, addr, nr_bytes, true)) | |
87 | return 0; | |
88 | ||
ef016f83 MF |
89 | value = dv_load_4 (source); |
90 | mmr_off = addr - cec->base; | |
91 | ||
92 | HW_TRACE_WRITE (); | |
93 | ||
94 | switch (mmr_off) | |
95 | { | |
96 | case mmr_offset(evt_override): | |
97 | cec->evt_override = value; | |
98 | break; | |
99 | case mmr_offset(imask): | |
100 | _cec_imask_write (cec, value); | |
101 | bfin_cec_check_pending (me, cec); | |
102 | break; | |
103 | case mmr_offset(ipend): | |
104 | /* Read-only register. */ | |
105 | break; | |
106 | case mmr_offset(ilat): | |
9922f803 | 107 | dv_w1c_4 (&cec->ilat, value, 0xffee); |
ef016f83 MF |
108 | break; |
109 | case mmr_offset(iprio): | |
110 | cec->iprio = (value & IVG_UNMASKABLE_B); | |
111 | break; | |
112 | } | |
113 | ||
114 | return nr_bytes; | |
115 | } | |
116 | ||
117 | static unsigned | |
118 | bfin_cec_io_read_buffer (struct hw *me, void *dest, | |
119 | int space, address_word addr, unsigned nr_bytes) | |
120 | { | |
121 | struct bfin_cec *cec = hw_data (me); | |
122 | bu32 mmr_off; | |
123 | bu32 *valuep; | |
124 | ||
466b619e MF |
125 | /* Invalid access mode is higher priority than missing register. */ |
126 | if (!dv_bfin_mmr_require_32 (me, addr, nr_bytes, false)) | |
127 | return 0; | |
128 | ||
ef016f83 MF |
129 | mmr_off = addr - cec->base; |
130 | valuep = (void *)((unsigned long)cec + mmr_base() + mmr_off); | |
131 | ||
132 | HW_TRACE_READ (); | |
133 | ||
134 | dv_store_4 (dest, *valuep); | |
135 | ||
136 | return nr_bytes; | |
137 | } | |
138 | ||
990d19fd MF |
139 | static const struct hw_port_descriptor bfin_cec_ports[] = |
140 | { | |
ef016f83 MF |
141 | { "emu", IVG_EMU, 0, input_port, }, |
142 | { "rst", IVG_RST, 0, input_port, }, | |
143 | { "nmi", IVG_NMI, 0, input_port, }, | |
144 | { "evx", IVG_EVX, 0, input_port, }, | |
145 | { "ivhw", IVG_IVHW, 0, input_port, }, | |
146 | { "ivtmr", IVG_IVTMR, 0, input_port, }, | |
147 | { "ivg7", IVG7, 0, input_port, }, | |
148 | { "ivg8", IVG8, 0, input_port, }, | |
149 | { "ivg9", IVG9, 0, input_port, }, | |
150 | { "ivg10", IVG10, 0, input_port, }, | |
151 | { "ivg11", IVG11, 0, input_port, }, | |
152 | { "ivg12", IVG12, 0, input_port, }, | |
153 | { "ivg13", IVG13, 0, input_port, }, | |
154 | { "ivg14", IVG14, 0, input_port, }, | |
155 | { "ivg15", IVG15, 0, input_port, }, | |
156 | { NULL, 0, 0, 0, }, | |
157 | }; | |
158 | ||
159 | static void | |
160 | bfin_cec_port_event (struct hw *me, int my_port, struct hw *source, | |
161 | int source_port, int level) | |
162 | { | |
163 | struct bfin_cec *cec = hw_data (me); | |
164 | _cec_raise (cec->cpu, cec, my_port); | |
165 | } | |
166 | ||
167 | static void | |
168 | attach_bfin_cec_regs (struct hw *me, struct bfin_cec *cec) | |
169 | { | |
170 | address_word attach_address; | |
171 | int attach_space; | |
172 | unsigned attach_size; | |
173 | reg_property_spec reg; | |
174 | ||
175 | if (hw_find_property (me, "reg") == NULL) | |
176 | hw_abort (me, "Missing \"reg\" property"); | |
177 | ||
178 | if (!hw_find_reg_array_property (me, "reg", 0, ®)) | |
179 | hw_abort (me, "\"reg\" property must contain three addr/size entries"); | |
180 | ||
181 | hw_unit_address_to_attach_address (hw_parent (me), | |
182 | ®.address, | |
183 | &attach_space, &attach_address, me); | |
184 | hw_unit_size_to_attach_size (hw_parent (me), ®.size, &attach_size, me); | |
185 | ||
186 | if (attach_size != BFIN_COREMMR_CEC_SIZE) | |
187 | hw_abort (me, "\"reg\" size must be %#x", BFIN_COREMMR_CEC_SIZE); | |
188 | ||
189 | hw_attach_address (hw_parent (me), | |
190 | 0, attach_space, attach_address, attach_size, me); | |
191 | ||
192 | cec->base = attach_address; | |
193 | /* XXX: should take from the device tree. */ | |
194 | cec->cpu = STATE_CPU (hw_system (me), 0); | |
195 | cec->me = me; | |
196 | } | |
197 | ||
198 | static void | |
199 | bfin_cec_finish (struct hw *me) | |
200 | { | |
201 | struct bfin_cec *cec; | |
202 | ||
203 | cec = HW_ZALLOC (me, struct bfin_cec); | |
204 | ||
205 | set_hw_data (me, cec); | |
206 | set_hw_io_read_buffer (me, bfin_cec_io_read_buffer); | |
207 | set_hw_io_write_buffer (me, bfin_cec_io_write_buffer); | |
208 | set_hw_ports (me, bfin_cec_ports); | |
209 | set_hw_port_event (me, bfin_cec_port_event); | |
210 | ||
211 | attach_bfin_cec_regs (me, cec); | |
212 | ||
213 | /* Initialize the CEC. */ | |
214 | cec->imask = IVG_UNMASKABLE_B; | |
215 | cec->ipend = IVG_RST_B | IVG_IRPTEN_B; | |
216 | } | |
217 | ||
81d126c3 MF |
218 | const struct hw_descriptor dv_bfin_cec_descriptor[] = |
219 | { | |
ef016f83 MF |
220 | {"bfin_cec", bfin_cec_finish,}, |
221 | {NULL, NULL}, | |
222 | }; | |
223 | ||
990d19fd MF |
224 | static const char * const excp_decoded[] = |
225 | { | |
ef016f83 MF |
226 | [VEC_SYS ] = "Custom exception 0 (system call)", |
227 | [VEC_EXCPT01 ] = "Custom exception 1 (software breakpoint)", | |
228 | [VEC_EXCPT02 ] = "Custom exception 2 (KGDB hook)", | |
229 | [VEC_EXCPT03 ] = "Custom exception 3 (userspace stack overflow)", | |
230 | [VEC_EXCPT04 ] = "Custom exception 4 (dump trace buffer)", | |
231 | [VEC_EXCPT05 ] = "Custom exception 5", | |
232 | [VEC_EXCPT06 ] = "Custom exception 6", | |
233 | [VEC_EXCPT07 ] = "Custom exception 7", | |
234 | [VEC_EXCPT08 ] = "Custom exception 8", | |
235 | [VEC_EXCPT09 ] = "Custom exception 9", | |
236 | [VEC_EXCPT10 ] = "Custom exception 10", | |
237 | [VEC_EXCPT11 ] = "Custom exception 11", | |
238 | [VEC_EXCPT12 ] = "Custom exception 12", | |
239 | [VEC_EXCPT13 ] = "Custom exception 13", | |
240 | [VEC_EXCPT14 ] = "Custom exception 14", | |
241 | [VEC_EXCPT15 ] = "Custom exception 15", | |
242 | [VEC_STEP ] = "Hardware single step", | |
243 | [VEC_OVFLOW ] = "Trace buffer overflow", | |
244 | [VEC_UNDEF_I ] = "Undefined instruction", | |
245 | [VEC_ILGAL_I ] = "Illegal instruction combo (multi-issue)", | |
246 | [VEC_CPLB_VL ] = "DCPLB protection violation", | |
247 | [VEC_MISALI_D ] = "Unaligned data access", | |
248 | [VEC_UNCOV ] = "Unrecoverable event (double fault)", | |
249 | [VEC_CPLB_M ] = "DCPLB miss", | |
250 | [VEC_CPLB_MHIT ] = "Multiple DCPLB hit", | |
251 | [VEC_WATCH ] = "Watchpoint match", | |
252 | [VEC_ISTRU_VL ] = "ADSP-BF535 only", | |
253 | [VEC_MISALI_I ] = "Unaligned instruction access", | |
254 | [VEC_CPLB_I_VL ] = "ICPLB protection violation", | |
255 | [VEC_CPLB_I_M ] = "ICPLB miss", | |
256 | [VEC_CPLB_I_MHIT] = "Multiple ICPLB hit", | |
257 | [VEC_ILL_RES ] = "Illegal supervisor resource", | |
258 | }; | |
259 | ||
260 | #define CEC_STATE(cpu) DV_STATE_CACHED (cpu, cec) | |
261 | ||
262 | #define __cec_get_ivg(val) (ffs ((val) & ~IVG_IRPTEN_B) - 1) | |
263 | #define _cec_get_ivg(cec) __cec_get_ivg ((cec)->ipend & ~IVG_EMU_B) | |
264 | ||
265 | int | |
266 | cec_get_ivg (SIM_CPU *cpu) | |
267 | { | |
268 | switch (STATE_ENVIRONMENT (CPU_STATE (cpu))) | |
269 | { | |
270 | case OPERATING_ENVIRONMENT: | |
271 | return _cec_get_ivg (CEC_STATE (cpu)); | |
272 | default: | |
273 | return IVG_USER; | |
274 | } | |
275 | } | |
276 | ||
277 | static bool | |
278 | _cec_is_supervisor_mode (struct bfin_cec *cec) | |
279 | { | |
280 | return (cec->ipend & ~(IVG_EMU_B | IVG_IRPTEN_B)); | |
281 | } | |
282 | bool | |
283 | cec_is_supervisor_mode (SIM_CPU *cpu) | |
284 | { | |
285 | switch (STATE_ENVIRONMENT (CPU_STATE (cpu))) | |
286 | { | |
287 | case OPERATING_ENVIRONMENT: | |
288 | return _cec_is_supervisor_mode (CEC_STATE (cpu)); | |
289 | case USER_ENVIRONMENT: | |
290 | return false; | |
291 | default: | |
292 | return true; | |
293 | } | |
294 | } | |
295 | static bool | |
296 | _cec_is_user_mode (struct bfin_cec *cec) | |
297 | { | |
298 | return !_cec_is_supervisor_mode (cec); | |
299 | } | |
300 | bool | |
301 | cec_is_user_mode (SIM_CPU *cpu) | |
302 | { | |
303 | return !cec_is_supervisor_mode (cpu); | |
304 | } | |
305 | static void | |
306 | _cec_require_supervisor (SIM_CPU *cpu, struct bfin_cec *cec) | |
307 | { | |
308 | if (_cec_is_user_mode (cec)) | |
309 | cec_exception (cpu, VEC_ILL_RES); | |
310 | } | |
311 | void | |
312 | cec_require_supervisor (SIM_CPU *cpu) | |
313 | { | |
314 | /* Do not call _cec_require_supervisor() to avoid CEC_STATE() | |
315 | as that macro requires OS operating mode. */ | |
316 | if (cec_is_user_mode (cpu)) | |
317 | cec_exception (cpu, VEC_ILL_RES); | |
318 | } | |
319 | ||
320 | #define excp_to_sim_halt(reason, sigrc) \ | |
321 | sim_engine_halt (CPU_STATE (cpu), cpu, NULL, PCREG, reason, sigrc) | |
322 | void | |
323 | cec_exception (SIM_CPU *cpu, int excp) | |
324 | { | |
325 | SIM_DESC sd = CPU_STATE (cpu); | |
326 | int sigrc = -1; | |
327 | ||
328 | TRACE_EVENTS (cpu, "processing exception %#x in EVT%i", excp, | |
329 | cec_get_ivg (cpu)); | |
330 | ||
331 | /* Ideally what would happen here for real hardware exceptions (not | |
332 | fake sim ones) is that: | |
333 | - For service exceptions (excp <= 0x11): | |
334 | RETX is the _next_ PC which can be tricky with jumps/hardware loops/... | |
335 | - For error exceptions (excp > 0x11): | |
336 | RETX is the _current_ PC (i.e. the one causing the exception) | |
337 | - PC is loaded with EVT3 MMR | |
338 | - ILAT/IPEND in CEC is updated depending on current IVG level | |
339 | - the fault address MMRs get updated with data/instruction info | |
340 | - Execution continues on in the EVT3 handler */ | |
341 | ||
342 | /* Handle simulator exceptions first. */ | |
343 | switch (excp) | |
344 | { | |
345 | case VEC_SIM_HLT: | |
346 | excp_to_sim_halt (sim_exited, 0); | |
347 | return; | |
348 | case VEC_SIM_ABORT: | |
349 | excp_to_sim_halt (sim_exited, 1); | |
350 | return; | |
351 | case VEC_SIM_TRAP: | |
352 | /* GDB expects us to step over EMUEXCPT. */ | |
353 | /* XXX: What about hwloops and EMUEXCPT at the end? | |
354 | Pretty sure gdb doesn't handle this already... */ | |
355 | SET_PCREG (PCREG + 2); | |
356 | /* Only trap when we are running in gdb. */ | |
357 | if (STATE_OPEN_KIND (sd) == SIM_OPEN_DEBUG) | |
358 | excp_to_sim_halt (sim_stopped, SIM_SIGTRAP); | |
359 | return; | |
360 | case VEC_SIM_DBGA: | |
361 | /* If running in gdb, simply trap. */ | |
362 | if (STATE_OPEN_KIND (sd) == SIM_OPEN_DEBUG) | |
363 | excp_to_sim_halt (sim_stopped, SIM_SIGTRAP); | |
364 | else | |
365 | excp_to_sim_halt (sim_exited, 2); | |
366 | } | |
367 | ||
368 | if (excp <= 0x3f) | |
369 | { | |
370 | SET_EXCAUSE (excp); | |
371 | if (STATE_ENVIRONMENT (sd) == OPERATING_ENVIRONMENT) | |
372 | { | |
373 | /* ICPLB regs always get updated. */ | |
374 | /* XXX: Should optimize this call path ... */ | |
375 | if (excp != VEC_MISALI_I && excp != VEC_MISALI_D | |
376 | && excp != VEC_CPLB_I_M && excp != VEC_CPLB_M | |
377 | && excp != VEC_CPLB_I_VL && excp != VEC_CPLB_VL | |
378 | && excp != VEC_CPLB_I_MHIT && excp != VEC_CPLB_MHIT) | |
379 | mmu_log_ifault (cpu); | |
380 | _cec_raise (cpu, CEC_STATE (cpu), IVG_EVX); | |
381 | /* We need to restart the engine so that we don't return | |
382 | and continue processing this bad insn. */ | |
383 | if (EXCAUSE >= 0x20) | |
384 | sim_engine_restart (sd, cpu, NULL, PCREG); | |
385 | return; | |
386 | } | |
387 | } | |
388 | ||
389 | TRACE_EVENTS (cpu, "running virtual exception handler"); | |
390 | ||
391 | switch (excp) | |
392 | { | |
393 | case VEC_SYS: | |
394 | bfin_syscall (cpu); | |
395 | break; | |
396 | ||
397 | case VEC_EXCPT01: /* Userspace gdb breakpoint. */ | |
398 | sigrc = SIM_SIGTRAP; | |
399 | break; | |
400 | ||
401 | case VEC_UNDEF_I: /* Undefined instruction. */ | |
402 | sigrc = SIM_SIGILL; | |
403 | break; | |
404 | ||
405 | case VEC_ILL_RES: /* Illegal supervisor resource. */ | |
406 | case VEC_MISALI_I: /* Misaligned instruction. */ | |
407 | sigrc = SIM_SIGBUS; | |
408 | break; | |
409 | ||
410 | case VEC_CPLB_M: | |
411 | case VEC_CPLB_I_M: | |
412 | sigrc = SIM_SIGSEGV; | |
413 | break; | |
414 | ||
415 | default: | |
416 | sim_io_eprintf (sd, "Unhandled exception %#x at 0x%08x (%s)\n", | |
417 | excp, PCREG, excp_decoded[excp]); | |
418 | sigrc = SIM_SIGILL; | |
419 | break; | |
420 | } | |
421 | ||
422 | if (sigrc != -1) | |
423 | excp_to_sim_halt (sim_stopped, sigrc); | |
424 | } | |
425 | ||
426 | bu32 cec_cli (SIM_CPU *cpu) | |
427 | { | |
428 | struct bfin_cec *cec; | |
429 | bu32 old_mask; | |
430 | ||
431 | if (STATE_ENVIRONMENT (CPU_STATE (cpu)) != OPERATING_ENVIRONMENT) | |
432 | return 0; | |
433 | ||
434 | cec = CEC_STATE (cpu); | |
435 | _cec_require_supervisor (cpu, cec); | |
436 | ||
437 | /* XXX: what about IPEND[4] ? */ | |
438 | old_mask = cec->imask; | |
439 | _cec_imask_write (cec, 0); | |
440 | ||
441 | TRACE_EVENTS (cpu, "CLI changed IMASK from %#x to %#x", old_mask, cec->imask); | |
442 | ||
443 | return old_mask; | |
444 | } | |
445 | ||
446 | void cec_sti (SIM_CPU *cpu, bu32 ints) | |
447 | { | |
448 | struct bfin_cec *cec; | |
449 | bu32 old_mask; | |
450 | ||
451 | if (STATE_ENVIRONMENT (CPU_STATE (cpu)) != OPERATING_ENVIRONMENT) | |
452 | return; | |
453 | ||
454 | cec = CEC_STATE (cpu); | |
455 | _cec_require_supervisor (cpu, cec); | |
456 | ||
457 | /* XXX: what about IPEND[4] ? */ | |
458 | old_mask = cec->imask; | |
459 | _cec_imask_write (cec, ints); | |
460 | ||
461 | TRACE_EVENTS (cpu, "STI changed IMASK from %#x to %#x", old_mask, cec->imask); | |
462 | ||
463 | /* Check for pending interrupts that are now enabled. */ | |
464 | _cec_check_pending (cpu, cec); | |
465 | } | |
466 | ||
467 | static void | |
468 | cec_irpten_enable (SIM_CPU *cpu, struct bfin_cec *cec) | |
469 | { | |
470 | /* Globally mask interrupts. */ | |
471 | TRACE_EVENTS (cpu, "setting IPEND[4] to globally mask interrupts"); | |
472 | cec->ipend |= IVG_IRPTEN_B; | |
473 | } | |
474 | ||
475 | static void | |
476 | cec_irpten_disable (SIM_CPU *cpu, struct bfin_cec *cec) | |
477 | { | |
478 | /* Clear global interrupt mask. */ | |
479 | TRACE_EVENTS (cpu, "clearing IPEND[4] to not globally mask interrupts"); | |
480 | cec->ipend &= ~IVG_IRPTEN_B; | |
481 | } | |
482 | ||
483 | static void | |
484 | _cec_raise (SIM_CPU *cpu, struct bfin_cec *cec, int ivg) | |
485 | { | |
486 | SIM_DESC sd = CPU_STATE (cpu); | |
487 | int curr_ivg = _cec_get_ivg (cec); | |
488 | bool snen; | |
489 | bool irpten; | |
490 | ||
491 | TRACE_EVENTS (cpu, "processing request for EVT%i while at EVT%i", | |
492 | ivg, curr_ivg); | |
493 | ||
494 | irpten = (cec->ipend & IVG_IRPTEN_B); | |
495 | snen = (SYSCFGREG & SYSCFG_SNEN); | |
496 | ||
497 | if (curr_ivg == -1) | |
498 | curr_ivg = IVG_USER; | |
499 | ||
500 | /* Just check for higher latched interrupts. */ | |
501 | if (ivg == -1) | |
502 | { | |
503 | if (irpten) | |
504 | goto done; /* All interrupts are masked anyways. */ | |
505 | ||
506 | ivg = __cec_get_ivg (cec->ilat & cec->imask); | |
507 | if (ivg < 0) | |
508 | goto done; /* Nothing latched. */ | |
509 | ||
510 | if (ivg > curr_ivg) | |
511 | goto done; /* Nothing higher latched. */ | |
512 | ||
513 | if (!snen && ivg == curr_ivg) | |
514 | goto done; /* Self nesting disabled. */ | |
515 | ||
516 | /* Still here, so fall through to raise to higher pending. */ | |
517 | } | |
518 | ||
519 | cec->ilat |= (1 << ivg); | |
520 | ||
521 | if (ivg <= IVG_EVX) | |
522 | { | |
523 | /* These two are always processed. */ | |
524 | if (ivg == IVG_EMU || ivg == IVG_RST) | |
525 | goto process_int; | |
526 | ||
527 | /* Anything lower might trigger a double fault. */ | |
528 | if (curr_ivg <= ivg) | |
529 | { | |
530 | /* Double fault ! :( */ | |
531 | SET_EXCAUSE (VEC_UNCOV); | |
532 | /* XXX: SET_RETXREG (...); */ | |
533 | sim_io_error (sd, "%s: double fault at 0x%08x ! :(", __func__, PCREG); | |
534 | excp_to_sim_halt (sim_stopped, SIM_SIGABRT); | |
535 | } | |
536 | ||
537 | /* No double fault -> always process. */ | |
538 | goto process_int; | |
539 | } | |
540 | else if (irpten && curr_ivg != IVG_USER) | |
541 | { | |
542 | /* Interrupts are globally masked. */ | |
543 | } | |
544 | else if (!(cec->imask & (1 << ivg))) | |
545 | { | |
546 | /* This interrupt is masked. */ | |
547 | } | |
548 | else if (ivg < curr_ivg || (snen && ivg == curr_ivg)) | |
549 | { | |
550 | /* Do transition! */ | |
551 | bu32 oldpc; | |
552 | ||
553 | process_int: | |
554 | cec->ipend |= (1 << ivg); | |
555 | cec->ilat &= ~(1 << ivg); | |
556 | ||
557 | /* Interrupts are processed in between insns which means the return | |
558 | point is the insn-to-be-executed (which is the current PC). But | |
559 | exceptions are handled while executing an insn, so we may have to | |
560 | advance the PC ourselves when setting RETX. | |
561 | XXX: Advancing the PC should only be for "service" exceptions, and | |
562 | handling them after executing the insn should be OK, which | |
563 | means we might be able to use the event interface for it. */ | |
564 | ||
565 | oldpc = PCREG; | |
566 | switch (ivg) | |
567 | { | |
568 | case IVG_EMU: | |
569 | /* Signal the JTAG ICE. */ | |
570 | /* XXX: what happens with 'raise 0' ? */ | |
571 | SET_RETEREG (oldpc); | |
572 | excp_to_sim_halt (sim_stopped, SIM_SIGTRAP); | |
573 | /* XXX: Need an easy way for gdb to signal it isnt here. */ | |
574 | cec->ipend &= ~IVG_EMU_B; | |
575 | break; | |
576 | case IVG_RST: | |
577 | /* Have the core reset simply exit (i.e. "shutdown"). */ | |
578 | excp_to_sim_halt (sim_exited, 0); | |
579 | break; | |
580 | case IVG_NMI: | |
581 | /* XXX: Should check this. */ | |
582 | SET_RETNREG (oldpc); | |
583 | break; | |
584 | case IVG_EVX: | |
585 | /* Non-service exceptions point to the excepting instruction. */ | |
586 | if (EXCAUSE >= 0x20) | |
587 | SET_RETXREG (oldpc); | |
588 | else | |
589 | { | |
590 | bu32 nextpc = hwloop_get_next_pc (cpu, oldpc, INSN_LEN); | |
591 | SET_RETXREG (nextpc); | |
592 | } | |
593 | ||
594 | break; | |
595 | case IVG_IRPTEN: | |
596 | /* XXX: what happens with 'raise 4' ? */ | |
597 | sim_io_error (sd, "%s: what to do with 'raise 4' ?", __func__); | |
598 | break; | |
599 | default: | |
600 | SET_RETIREG (oldpc | (ivg == curr_ivg ? 1 : 0)); | |
601 | break; | |
602 | } | |
603 | ||
604 | /* If EVT_OVERRIDE is in effect (IVG7+), use the reset address. */ | |
605 | if ((cec->evt_override & 0xff80) & (1 << ivg)) | |
606 | SET_PCREG (cec_get_reset_evt (cpu)); | |
607 | else | |
608 | SET_PCREG (cec_get_evt (cpu, ivg)); | |
609 | ||
bb11f3ed | 610 | BFIN_TRACE_BRANCH (cpu, oldpc, PCREG, -1, "CEC changed PC (to EVT%i):", ivg); |
ef016f83 MF |
611 | BFIN_CPU_STATE.did_jump = true; |
612 | ||
613 | /* Enable the global interrupt mask upon interrupt entry. */ | |
614 | if (ivg >= IVG_IVHW) | |
615 | cec_irpten_enable (cpu, cec); | |
616 | } | |
617 | ||
618 | /* When moving between states, don't let internal states bleed through. */ | |
619 | DIS_ALGN_EXPT &= ~1; | |
620 | ||
621 | /* When going from user to super, we set LSB in LB regs to avoid | |
622 | misbehavior and/or malicious code. | |
623 | Also need to load SP alias with KSP. */ | |
624 | if (curr_ivg == IVG_USER) | |
625 | { | |
626 | int i; | |
627 | for (i = 0; i < 2; ++i) | |
628 | if (!(LBREG (i) & 1)) | |
629 | SET_LBREG (i, LBREG (i) | 1); | |
630 | SET_USPREG (SPREG); | |
631 | SET_SPREG (KSPREG); | |
632 | } | |
633 | ||
634 | done: | |
635 | TRACE_EVENTS (cpu, "now at EVT%i", _cec_get_ivg (cec)); | |
636 | } | |
637 | ||
638 | static bu32 | |
639 | cec_read_ret_reg (SIM_CPU *cpu, int ivg) | |
640 | { | |
641 | switch (ivg) | |
642 | { | |
643 | case IVG_EMU: return RETEREG; | |
644 | case IVG_NMI: return RETNREG; | |
645 | case IVG_EVX: return RETXREG; | |
646 | default: return RETIREG; | |
647 | } | |
648 | } | |
649 | ||
650 | void | |
651 | cec_latch (SIM_CPU *cpu, int ivg) | |
652 | { | |
653 | struct bfin_cec *cec; | |
654 | ||
655 | if (STATE_ENVIRONMENT (CPU_STATE (cpu)) != OPERATING_ENVIRONMENT) | |
656 | { | |
657 | bu32 oldpc = PCREG; | |
658 | SET_PCREG (cec_read_ret_reg (cpu, ivg)); | |
bb11f3ed | 659 | BFIN_TRACE_BRANCH (cpu, oldpc, PCREG, -1, "CEC changed PC"); |
ef016f83 MF |
660 | return; |
661 | } | |
662 | ||
663 | cec = CEC_STATE (cpu); | |
664 | cec->ilat |= (1 << ivg); | |
665 | _cec_check_pending (cpu, cec); | |
666 | } | |
667 | ||
668 | void | |
669 | cec_hwerr (SIM_CPU *cpu, int hwerr) | |
670 | { | |
671 | SET_HWERRCAUSE (hwerr); | |
672 | cec_latch (cpu, IVG_IVHW); | |
673 | } | |
674 | ||
675 | void | |
676 | cec_return (SIM_CPU *cpu, int ivg) | |
677 | { | |
678 | SIM_DESC sd = CPU_STATE (cpu); | |
679 | struct bfin_cec *cec; | |
680 | bool snen; | |
681 | int curr_ivg; | |
682 | bu32 oldpc, newpc; | |
683 | ||
684 | oldpc = PCREG; | |
685 | ||
686 | BFIN_CPU_STATE.did_jump = true; | |
687 | if (STATE_ENVIRONMENT (sd) != OPERATING_ENVIRONMENT) | |
688 | { | |
689 | SET_PCREG (cec_read_ret_reg (cpu, ivg)); | |
bb11f3ed | 690 | BFIN_TRACE_BRANCH (cpu, oldpc, PCREG, -1, "CEC changed PC"); |
ef016f83 MF |
691 | return; |
692 | } | |
693 | ||
694 | cec = CEC_STATE (cpu); | |
695 | ||
696 | /* XXX: This isn't entirely correct ... */ | |
697 | cec->ipend &= ~IVG_EMU_B; | |
698 | ||
699 | curr_ivg = _cec_get_ivg (cec); | |
700 | if (curr_ivg == -1) | |
701 | curr_ivg = IVG_USER; | |
702 | if (ivg == -1) | |
703 | ivg = curr_ivg; | |
704 | ||
705 | TRACE_EVENTS (cpu, "returning from EVT%i (should be EVT%i)", curr_ivg, ivg); | |
706 | ||
707 | /* Not allowed to return from usermode. */ | |
708 | if (curr_ivg == IVG_USER) | |
709 | cec_exception (cpu, VEC_ILL_RES); | |
710 | ||
711 | if (ivg > IVG15 || ivg < 0) | |
712 | sim_io_error (sd, "%s: ivg %i out of range !", __func__, ivg); | |
713 | ||
714 | _cec_require_supervisor (cpu, cec); | |
715 | ||
716 | switch (ivg) | |
717 | { | |
718 | case IVG_EMU: | |
719 | /* RTE -- only valid in emulation mode. */ | |
720 | /* XXX: What does the hardware do ? */ | |
721 | if (curr_ivg != IVG_EMU) | |
722 | cec_exception (cpu, VEC_ILL_RES); | |
723 | break; | |
724 | case IVG_NMI: | |
725 | /* RTN -- only valid in NMI. */ | |
726 | /* XXX: What does the hardware do ? */ | |
727 | if (curr_ivg != IVG_NMI) | |
728 | cec_exception (cpu, VEC_ILL_RES); | |
729 | break; | |
730 | case IVG_EVX: | |
731 | /* RTX -- only valid in exception. */ | |
732 | /* XXX: What does the hardware do ? */ | |
733 | if (curr_ivg != IVG_EVX) | |
734 | cec_exception (cpu, VEC_ILL_RES); | |
735 | break; | |
736 | default: | |
737 | /* RTI -- not valid in emulation, nmi, exception, or user. */ | |
738 | /* XXX: What does the hardware do ? */ | |
739 | if (curr_ivg == IVG_EMU || curr_ivg == IVG_NMI | |
740 | || curr_ivg == IVG_EVX || curr_ivg == IVG_USER) | |
741 | cec_exception (cpu, VEC_ILL_RES); | |
742 | break; | |
743 | case IVG_IRPTEN: | |
744 | /* XXX: Is this even possible ? */ | |
745 | excp_to_sim_halt (sim_stopped, SIM_SIGABRT); | |
746 | break; | |
747 | } | |
748 | newpc = cec_read_ret_reg (cpu, ivg); | |
749 | ||
750 | /* XXX: Does this nested trick work on EMU/NMI/EVX ? */ | |
751 | snen = (newpc & 1); | |
752 | /* XXX: Delayed clear shows bad PCREG register trace above ? */ | |
753 | SET_PCREG (newpc & ~1); | |
754 | ||
bb11f3ed | 755 | BFIN_TRACE_BRANCH (cpu, oldpc, PCREG, -1, "CEC changed PC (from EVT%i)", ivg); |
ef016f83 | 756 | |
bb11f3ed | 757 | /* Update ipend after the BFIN_TRACE_BRANCH so dv-bfin_trace |
ef016f83 MF |
758 | knows current CEC state wrt overflow. */ |
759 | if (!snen) | |
760 | cec->ipend &= ~(1 << ivg); | |
761 | ||
762 | /* Disable global interrupt mask to let any interrupt take over, but | |
763 | only when we were already in a RTI level. Only way we could have | |
764 | raised at that point is if it was cleared in the first place. */ | |
765 | if (ivg >= IVG_IVHW || ivg == IVG_RST) | |
766 | cec_irpten_disable (cpu, cec); | |
767 | ||
768 | /* When going from super to user, we clear LSB in LB regs in case | |
769 | it was set on the transition up. | |
770 | Also need to load SP alias with USP. */ | |
771 | if (_cec_get_ivg (cec) == -1) | |
772 | { | |
773 | int i; | |
774 | for (i = 0; i < 2; ++i) | |
775 | if (LBREG (i) & 1) | |
776 | SET_LBREG (i, LBREG (i) & ~1); | |
777 | SET_KSPREG (SPREG); | |
778 | SET_SPREG (USPREG); | |
779 | } | |
780 | ||
781 | /* Check for pending interrupts before we return to usermode. */ | |
782 | _cec_check_pending (cpu, cec); | |
783 | } | |
784 | ||
785 | void | |
786 | cec_push_reti (SIM_CPU *cpu) | |
787 | { | |
788 | /* XXX: Need to check hardware with popped RETI value | |
789 | and bit 1 is set (when handling nested interrupts). | |
790 | Also need to check behavior wrt SNEN in SYSCFG. */ | |
791 | struct bfin_cec *cec; | |
792 | ||
793 | if (STATE_ENVIRONMENT (CPU_STATE (cpu)) != OPERATING_ENVIRONMENT) | |
794 | return; | |
795 | ||
796 | TRACE_EVENTS (cpu, "pushing RETI"); | |
797 | ||
798 | cec = CEC_STATE (cpu); | |
799 | cec_irpten_disable (cpu, cec); | |
800 | /* Check for pending interrupts. */ | |
801 | _cec_check_pending (cpu, cec); | |
802 | } | |
803 | ||
804 | void | |
805 | cec_pop_reti (SIM_CPU *cpu) | |
806 | { | |
807 | /* XXX: Need to check hardware with popped RETI value | |
808 | and bit 1 is set (when handling nested interrupts). | |
809 | Also need to check behavior wrt SNEN in SYSCFG. */ | |
810 | struct bfin_cec *cec; | |
811 | ||
812 | if (STATE_ENVIRONMENT (CPU_STATE (cpu)) != OPERATING_ENVIRONMENT) | |
813 | return; | |
814 | ||
815 | TRACE_EVENTS (cpu, "popping RETI"); | |
816 | ||
817 | cec = CEC_STATE (cpu); | |
818 | cec_irpten_enable (cpu, cec); | |
819 | } |