cortex_m: Fix single stepping will not return to debug mode sometimes
[fw/openocd] / src / target / cortex_m.c
1 /***************************************************************************
2  *   Copyright (C) 2005 by Dominic Rath                                    *
3  *   Dominic.Rath@gmx.de                                                   *
4  *                                                                         *
5  *   Copyright (C) 2006 by Magnus Lundin                                   *
6  *   lundin@mlu.mine.nu                                                    *
7  *                                                                         *
8  *   Copyright (C) 2008 by Spencer Oliver                                  *
9  *   spen@spen-soft.co.uk                                                  *
10  *                                                                         *
11  *   This program is free software; you can redistribute it and/or modify  *
12  *   it under the terms of the GNU General Public License as published by  *
13  *   the Free Software Foundation; either version 2 of the License, or     *
14  *   (at your option) any later version.                                   *
15  *                                                                         *
16  *   This program is distributed in the hope that it will be useful,       *
17  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
18  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
19  *   GNU General Public License for more details.                          *
20  *                                                                         *
21  *   You should have received a copy of the GNU General Public License     *
22  *   along with this program; if not, write to the                         *
23  *   Free Software Foundation, Inc.,                                       *
24  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
25  *                                                                         *
26  *                                                                         *
27  *   Cortex-M3(tm) TRM, ARM DDI 0337E (r1p1) and 0337G (r2p0)              *
28  *                                                                         *
29  ***************************************************************************/
30 #ifdef HAVE_CONFIG_H
31 #include "config.h"
32 #endif
33
34 #include "jtag/interface.h"
35 #include "breakpoints.h"
36 #include "cortex_m.h"
37 #include "target_request.h"
38 #include "target_type.h"
39 #include "arm_disassembler.h"
40 #include "register.h"
41 #include "arm_opcodes.h"
42 #include "arm_semihosting.h"
43 #include <helper/time_support.h>
44
45 /* NOTE:  most of this should work fine for the Cortex-M1 and
46  * Cortex-M0 cores too, although they're ARMv6-M not ARMv7-M.
47  * Some differences:  M0/M1 doesn't have FBP remapping or the
48  * DWT tracing/profiling support.  (So the cycle counter will
49  * not be usable; the other stuff isn't currently used here.)
50  *
51  * Although there are some workarounds for errata seen only in r0p0
52  * silicon, such old parts are hard to find and thus not much tested
53  * any longer.
54  */
55
56 /**
57  * Returns the type of a break point required by address location
58  */
59 #define BKPT_TYPE_BY_ADDR(addr) ((addr) < 0x20000000 ? BKPT_HARD : BKPT_SOFT)
60
61
62 /* forward declarations */
63 static int cortex_m3_store_core_reg_u32(struct target *target,
64         enum armv7m_regtype type, uint32_t num, uint32_t value);
65
66 static int cortexm3_dap_read_coreregister_u32(struct adiv5_dap *swjdp,
67         uint32_t *value, int regnum)
68 {
69         int retval;
70         uint32_t dcrdr;
71
72         /* because the DCB_DCRDR is used for the emulated dcc channel
73          * we have to save/restore the DCB_DCRDR when used */
74
75         retval = mem_ap_read_u32(swjdp, DCB_DCRDR, &dcrdr);
76         if (retval != ERROR_OK)
77                 return retval;
78
79         /* mem_ap_write_u32(swjdp, DCB_DCRSR, regnum); */
80         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
81         if (retval != ERROR_OK)
82                 return retval;
83         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum);
84         if (retval != ERROR_OK)
85                 return retval;
86
87         /* mem_ap_read_u32(swjdp, DCB_DCRDR, value); */
88         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
89         if (retval != ERROR_OK)
90                 return retval;
91         retval = dap_queue_ap_read(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
92         if (retval != ERROR_OK)
93                 return retval;
94
95         retval = dap_run(swjdp);
96         if (retval != ERROR_OK)
97                 return retval;
98
99         /* restore DCB_DCRDR - this needs to be in a seperate
100          * transaction otherwise the emulated DCC channel breaks */
101         if (retval == ERROR_OK)
102                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DCRDR, dcrdr);
103
104         return retval;
105 }
106
107 static int cortexm3_dap_write_coreregister_u32(struct adiv5_dap *swjdp,
108         uint32_t value, int regnum)
109 {
110         int retval;
111         uint32_t dcrdr;
112
113         /* because the DCB_DCRDR is used for the emulated dcc channel
114          * we have to save/restore the DCB_DCRDR when used */
115
116         retval = mem_ap_read_u32(swjdp, DCB_DCRDR, &dcrdr);
117         if (retval != ERROR_OK)
118                 return retval;
119
120         /* mem_ap_write_u32(swjdp, DCB_DCRDR, core_regs[i]); */
121         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRDR & 0xFFFFFFF0);
122         if (retval != ERROR_OK)
123                 return retval;
124         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRDR & 0xC), value);
125         if (retval != ERROR_OK)
126                 return retval;
127
128         /* mem_ap_write_u32(swjdp, DCB_DCRSR, i | DCRSR_WnR); */
129         retval = dap_setup_accessport(swjdp, CSW_32BIT | CSW_ADDRINC_OFF, DCB_DCRSR & 0xFFFFFFF0);
130         if (retval != ERROR_OK)
131                 return retval;
132         retval = dap_queue_ap_write(swjdp, AP_REG_BD0 | (DCB_DCRSR & 0xC), regnum | DCRSR_WnR);
133         if (retval != ERROR_OK)
134                 return retval;
135
136         retval = dap_run(swjdp);
137         if (retval != ERROR_OK)
138                 return retval;
139
140         /* restore DCB_DCRDR - this needs to be in a seperate
141          * transaction otherwise the emulated DCC channel breaks */
142         if (retval == ERROR_OK)
143                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DCRDR, dcrdr);
144
145         return retval;
146 }
147
148 static int cortex_m3_write_debug_halt_mask(struct target *target,
149         uint32_t mask_on, uint32_t mask_off)
150 {
151         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
152         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
153
154         /* mask off status bits */
155         cortex_m3->dcb_dhcsr &= ~((0xFFFF << 16) | mask_off);
156         /* create new register mask */
157         cortex_m3->dcb_dhcsr |= DBGKEY | C_DEBUGEN | mask_on;
158
159         return mem_ap_write_atomic_u32(swjdp, DCB_DHCSR, cortex_m3->dcb_dhcsr);
160 }
161
162 static int cortex_m3_clear_halt(struct target *target)
163 {
164         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
165         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
166         int retval;
167
168         /* clear step if any */
169         cortex_m3_write_debug_halt_mask(target, C_HALT, C_STEP);
170
171         /* Read Debug Fault Status Register */
172         retval = mem_ap_read_atomic_u32(swjdp, NVIC_DFSR, &cortex_m3->nvic_dfsr);
173         if (retval != ERROR_OK)
174                 return retval;
175
176         /* Clear Debug Fault Status */
177         retval = mem_ap_write_atomic_u32(swjdp, NVIC_DFSR, cortex_m3->nvic_dfsr);
178         if (retval != ERROR_OK)
179                 return retval;
180         LOG_DEBUG(" NVIC_DFSR 0x%" PRIx32 "", cortex_m3->nvic_dfsr);
181
182         return ERROR_OK;
183 }
184
185 static int cortex_m3_single_step_core(struct target *target)
186 {
187         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
188         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
189         uint32_t dhcsr_save;
190         int retval;
191
192         /* backup dhcsr reg */
193         dhcsr_save = cortex_m3->dcb_dhcsr;
194
195         /* Mask interrupts before clearing halt, if done already.  This avoids
196          * Erratum 377497 (fixed in r1p0) where setting MASKINTS while clearing
197          * HALT can put the core into an unknown state.
198          */
199         if (!(cortex_m3->dcb_dhcsr & C_MASKINTS)) {
200                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
201                                 DBGKEY | C_MASKINTS | C_HALT | C_DEBUGEN);
202                 if (retval != ERROR_OK)
203                         return retval;
204         }
205         retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
206                         DBGKEY | C_MASKINTS | C_STEP | C_DEBUGEN);
207         if (retval != ERROR_OK)
208                 return retval;
209         LOG_DEBUG(" ");
210
211         /* restore dhcsr reg */
212         cortex_m3->dcb_dhcsr = dhcsr_save;
213         cortex_m3_clear_halt(target);
214
215         return ERROR_OK;
216 }
217
218 static int cortex_m3_endreset_event(struct target *target)
219 {
220         int i;
221         int retval;
222         uint32_t dcb_demcr;
223         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
224         struct armv7m_common *armv7m = &cortex_m3->armv7m;
225         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
226         struct cortex_m3_fp_comparator *fp_list = cortex_m3->fp_comparator_list;
227         struct cortex_m3_dwt_comparator *dwt_list = cortex_m3->dwt_comparator_list;
228
229         /* REVISIT The four debug monitor bits are currently ignored... */
230         retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &dcb_demcr);
231         if (retval != ERROR_OK)
232                 return retval;
233         LOG_DEBUG("DCB_DEMCR = 0x%8.8" PRIx32 "", dcb_demcr);
234
235         /* this register is used for emulated dcc channel */
236         retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
237         if (retval != ERROR_OK)
238                 return retval;
239
240         /* Enable debug requests */
241         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
242         if (retval != ERROR_OK)
243                 return retval;
244         if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN)) {
245                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN);
246                 if (retval != ERROR_OK)
247                         return retval;
248         }
249
250         /* clear any interrupt masking */
251         cortex_m3_write_debug_halt_mask(target, 0, C_MASKINTS);
252
253         /* Enable features controlled by ITM and DWT blocks, and catch only
254          * the vectors we were told to pay attention to.
255          *
256          * Target firmware is responsible for all fault handling policy
257          * choices *EXCEPT* explicitly scripted overrides like "vector_catch"
258          * or manual updates to the NVIC SHCSR and CCR registers.
259          */
260         retval = mem_ap_write_u32(swjdp, DCB_DEMCR, TRCENA | armv7m->demcr);
261         if (retval != ERROR_OK)
262                 return retval;
263
264         /* Paranoia: evidently some (early?) chips don't preserve all the
265          * debug state (including FBP, DWT, etc) across reset...
266          */
267
268         /* Enable FPB */
269         retval = target_write_u32(target, FP_CTRL, 3);
270         if (retval != ERROR_OK)
271                 return retval;
272
273         cortex_m3->fpb_enabled = 1;
274
275         /* Restore FPB registers */
276         for (i = 0; i < cortex_m3->fp_num_code + cortex_m3->fp_num_lit; i++) {
277                 retval = target_write_u32(target, fp_list[i].fpcr_address, fp_list[i].fpcr_value);
278                 if (retval != ERROR_OK)
279                         return retval;
280         }
281
282         /* Restore DWT registers */
283         for (i = 0; i < cortex_m3->dwt_num_comp; i++) {
284                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 0,
285                                 dwt_list[i].comp);
286                 if (retval != ERROR_OK)
287                         return retval;
288                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 4,
289                                 dwt_list[i].mask);
290                 if (retval != ERROR_OK)
291                         return retval;
292                 retval = target_write_u32(target, dwt_list[i].dwt_comparator_address + 8,
293                                 dwt_list[i].function);
294                 if (retval != ERROR_OK)
295                         return retval;
296         }
297         retval = dap_run(swjdp);
298         if (retval != ERROR_OK)
299                 return retval;
300
301         register_cache_invalidate(cortex_m3->armv7m.core_cache);
302
303         /* make sure we have latest dhcsr flags */
304         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
305
306         return retval;
307 }
308
309 static int cortex_m3_examine_debug_reason(struct target *target)
310 {
311         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
312
313         /* THIS IS NOT GOOD, TODO - better logic for detection of debug state reason
314          * only check the debug reason if we don't know it already */
315
316         if ((target->debug_reason != DBG_REASON_DBGRQ)
317                 && (target->debug_reason != DBG_REASON_SINGLESTEP)) {
318                 if (cortex_m3->nvic_dfsr & DFSR_BKPT) {
319                         target->debug_reason = DBG_REASON_BREAKPOINT;
320                         if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
321                                 target->debug_reason = DBG_REASON_WPTANDBKPT;
322                 } else if (cortex_m3->nvic_dfsr & DFSR_DWTTRAP)
323                         target->debug_reason = DBG_REASON_WATCHPOINT;
324                 else if (cortex_m3->nvic_dfsr & DFSR_VCATCH)
325                         target->debug_reason = DBG_REASON_BREAKPOINT;
326                 else    /* EXTERNAL, HALTED */
327                         target->debug_reason = DBG_REASON_UNDEFINED;
328         }
329
330         return ERROR_OK;
331 }
332
333 static int cortex_m3_examine_exception_reason(struct target *target)
334 {
335         uint32_t shcsr = 0, except_sr = 0, cfsr = -1, except_ar = -1;
336         struct armv7m_common *armv7m = target_to_armv7m(target);
337         struct adiv5_dap *swjdp = armv7m->arm.dap;
338         int retval;
339
340         retval = mem_ap_read_u32(swjdp, NVIC_SHCSR, &shcsr);
341         if (retval != ERROR_OK)
342                 return retval;
343         switch (armv7m->exception_number) {
344                 case 2: /* NMI */
345                         break;
346                 case 3: /* Hard Fault */
347                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_HFSR, &except_sr);
348                         if (retval != ERROR_OK)
349                                 return retval;
350                         if (except_sr & 0x40000000) {
351                                 retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &cfsr);
352                                 if (retval != ERROR_OK)
353                                         return retval;
354                         }
355                         break;
356                 case 4: /* Memory Management */
357                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
358                         if (retval != ERROR_OK)
359                                 return retval;
360                         retval = mem_ap_read_u32(swjdp, NVIC_MMFAR, &except_ar);
361                         if (retval != ERROR_OK)
362                                 return retval;
363                         break;
364                 case 5: /* Bus Fault */
365                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
366                         if (retval != ERROR_OK)
367                                 return retval;
368                         retval = mem_ap_read_u32(swjdp, NVIC_BFAR, &except_ar);
369                         if (retval != ERROR_OK)
370                                 return retval;
371                         break;
372                 case 6: /* Usage Fault */
373                         retval = mem_ap_read_u32(swjdp, NVIC_CFSR, &except_sr);
374                         if (retval != ERROR_OK)
375                                 return retval;
376                         break;
377                 case 11:        /* SVCall */
378                         break;
379                 case 12:        /* Debug Monitor */
380                         retval = mem_ap_read_u32(swjdp, NVIC_DFSR, &except_sr);
381                         if (retval != ERROR_OK)
382                                 return retval;
383                         break;
384                 case 14:        /* PendSV */
385                         break;
386                 case 15:        /* SysTick */
387                         break;
388                 default:
389                         except_sr = 0;
390                         break;
391         }
392         retval = dap_run(swjdp);
393         if (retval == ERROR_OK)
394                 LOG_DEBUG("%s SHCSR 0x%" PRIx32 ", SR 0x%" PRIx32
395                         ", CFSR 0x%" PRIx32 ", AR 0x%" PRIx32,
396                         armv7m_exception_string(armv7m->exception_number),
397                         shcsr, except_sr, cfsr, except_ar);
398         return retval;
399 }
400
401 static int cortex_m3_debug_entry(struct target *target)
402 {
403         int i;
404         uint32_t xPSR;
405         int retval;
406         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
407         struct armv7m_common *armv7m = &cortex_m3->armv7m;
408         struct arm *arm = &armv7m->arm;
409         struct adiv5_dap *swjdp = armv7m->arm.dap;
410         struct reg *r;
411
412         LOG_DEBUG(" ");
413
414         cortex_m3_clear_halt(target);
415         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
416         if (retval != ERROR_OK)
417                 return retval;
418
419         retval = armv7m->examine_debug_reason(target);
420         if (retval != ERROR_OK)
421                 return retval;
422
423         /* Examine target state and mode
424          * First load register acessible through core debug port*/
425         int num_regs = armv7m->core_cache->num_regs;
426
427         for (i = 0; i < num_regs; i++) {
428                 if (!armv7m->core_cache->reg_list[i].valid)
429                         armv7m->read_core_reg(target, i);
430         }
431
432         r = armv7m->core_cache->reg_list + ARMV7M_xPSR;
433         xPSR = buf_get_u32(r->value, 0, 32);
434
435 #ifdef ARMV7_GDB_HACKS
436         /* FIXME this breaks on scan chains with more than one Cortex-M3.
437          * Instead, each CM3 should have its own dummy value...
438          */
439         /* copy real xpsr reg for gdb, setting thumb bit */
440         buf_set_u32(armv7m_gdb_dummy_cpsr_value, 0, 32, xPSR);
441         buf_set_u32(armv7m_gdb_dummy_cpsr_value, 5, 1, 1);
442         armv7m_gdb_dummy_cpsr_reg.valid = r->valid;
443         armv7m_gdb_dummy_cpsr_reg.dirty = r->dirty;
444 #endif
445
446         /* For IT instructions xPSR must be reloaded on resume and clear on debug exec */
447         if (xPSR & 0xf00) {
448                 r->dirty = r->valid;
449                 cortex_m3_store_core_reg_u32(target, ARMV7M_REGISTER_CORE_GP, 16, xPSR & ~0xff);
450         }
451
452         /* Are we in an exception handler */
453         if (xPSR & 0x1FF) {
454                 armv7m->core_mode = ARMV7M_MODE_HANDLER;
455                 armv7m->exception_number = (xPSR & 0x1FF);
456
457                 arm->core_mode = ARM_MODE_HANDLER;
458                 arm->map = armv7m_msp_reg_map;
459         } else {
460                 unsigned control = buf_get_u32(armv7m->core_cache
461                                 ->reg_list[ARMV7M_CONTROL].value, 0, 2);
462
463                 /* is this thread privileged? */
464                 armv7m->core_mode = control & 1;
465                 arm->core_mode = armv7m->core_mode
466                         ? ARM_MODE_USER_THREAD
467                         : ARM_MODE_THREAD;
468
469                 /* which stack is it using? */
470                 if (control & 2)
471                         arm->map = armv7m_psp_reg_map;
472                 else
473                         arm->map = armv7m_msp_reg_map;
474
475                 armv7m->exception_number = 0;
476         }
477
478         if (armv7m->exception_number)
479                 cortex_m3_examine_exception_reason(target);
480
481         LOG_DEBUG("entered debug state in core mode: %s at PC 0x%" PRIx32 ", target->state: %s",
482                 armv7m_mode_strings[armv7m->core_mode],
483                 *(uint32_t *)(arm->pc->value),
484                 target_state_name(target));
485
486         if (armv7m->post_debug_entry) {
487                 retval = armv7m->post_debug_entry(target);
488                 if (retval != ERROR_OK)
489                         return retval;
490         }
491
492         return ERROR_OK;
493 }
494
495 static int cortex_m3_poll(struct target *target)
496 {
497         int detected_failure = ERROR_OK;
498         int retval = ERROR_OK;
499         enum target_state prev_target_state = target->state;
500         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
501         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
502
503         /* Read from Debug Halting Control and Status Register */
504         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
505         if (retval != ERROR_OK) {
506                 target->state = TARGET_UNKNOWN;
507                 return retval;
508         }
509
510         /* Recover from lockup.  See ARMv7-M architecture spec,
511          * section B1.5.15 "Unrecoverable exception cases".
512          */
513         if (cortex_m3->dcb_dhcsr & S_LOCKUP) {
514                 LOG_ERROR("%s -- clearing lockup after double fault",
515                         target_name(target));
516                 cortex_m3_write_debug_halt_mask(target, C_HALT, 0);
517                 target->debug_reason = DBG_REASON_DBGRQ;
518
519                 /* We have to execute the rest (the "finally" equivalent, but
520                  * still throw this exception again).
521                  */
522                 detected_failure = ERROR_FAIL;
523
524                 /* refresh status bits */
525                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
526                 if (retval != ERROR_OK)
527                         return retval;
528         }
529
530         if (cortex_m3->dcb_dhcsr & S_RESET_ST) {
531                 /* check if still in reset */
532                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
533                 if (retval != ERROR_OK)
534                         return retval;
535
536                 if (cortex_m3->dcb_dhcsr & S_RESET_ST) {
537                         target->state = TARGET_RESET;
538                         return ERROR_OK;
539                 }
540         }
541
542         if (target->state == TARGET_RESET) {
543                 /* Cannot switch context while running so endreset is
544                  * called with target->state == TARGET_RESET
545                  */
546                 LOG_DEBUG("Exit from reset with dcb_dhcsr 0x%" PRIx32,
547                         cortex_m3->dcb_dhcsr);
548                 cortex_m3_endreset_event(target);
549                 target->state = TARGET_RUNNING;
550                 prev_target_state = TARGET_RUNNING;
551         }
552
553         if (cortex_m3->dcb_dhcsr & S_HALT) {
554                 target->state = TARGET_HALTED;
555
556                 if ((prev_target_state == TARGET_RUNNING) || (prev_target_state == TARGET_RESET)) {
557                         retval = cortex_m3_debug_entry(target);
558                         if (retval != ERROR_OK)
559                                 return retval;
560
561                         if (arm_semihosting(target, &retval) != 0)
562                                 return retval;
563
564                         target_call_event_callbacks(target, TARGET_EVENT_HALTED);
565                 }
566                 if (prev_target_state == TARGET_DEBUG_RUNNING) {
567                         LOG_DEBUG(" ");
568                         retval = cortex_m3_debug_entry(target);
569                         if (retval != ERROR_OK)
570                                 return retval;
571
572                         target_call_event_callbacks(target, TARGET_EVENT_DEBUG_HALTED);
573                 }
574         }
575
576         /* REVISIT when S_SLEEP is set, it's in a Sleep or DeepSleep state.
577          * How best to model low power modes?
578          */
579
580         if (target->state == TARGET_UNKNOWN) {
581                 /* check if processor is retiring instructions */
582                 if (cortex_m3->dcb_dhcsr & S_RETIRE_ST) {
583                         target->state = TARGET_RUNNING;
584                         retval = ERROR_OK;
585                 }
586         }
587
588         /* Did we detect a failure condition that we cleared? */
589         if (detected_failure != ERROR_OK)
590                 retval = detected_failure;
591         return retval;
592 }
593
594 static int cortex_m3_halt(struct target *target)
595 {
596         LOG_DEBUG("target->state: %s",
597                 target_state_name(target));
598
599         if (target->state == TARGET_HALTED) {
600                 LOG_DEBUG("target was already halted");
601                 return ERROR_OK;
602         }
603
604         if (target->state == TARGET_UNKNOWN)
605                 LOG_WARNING("target was in unknown state when halt was requested");
606
607         if (target->state == TARGET_RESET) {
608                 if ((jtag_get_reset_config() & RESET_SRST_PULLS_TRST) && jtag_get_srst()) {
609                         LOG_ERROR("can't request a halt while in reset if nSRST pulls nTRST");
610                         return ERROR_TARGET_FAILURE;
611                 } else {
612                         /* we came here in a reset_halt or reset_init sequence
613                          * debug entry was already prepared in cortex_m3_assert_reset()
614                          */
615                         target->debug_reason = DBG_REASON_DBGRQ;
616
617                         return ERROR_OK;
618                 }
619         }
620
621         /* Write to Debug Halting Control and Status Register */
622         cortex_m3_write_debug_halt_mask(target, C_HALT, 0);
623
624         target->debug_reason = DBG_REASON_DBGRQ;
625
626         return ERROR_OK;
627 }
628
629 static int cortex_m3_soft_reset_halt(struct target *target)
630 {
631         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
632         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
633         uint32_t dcb_dhcsr = 0;
634         int retval, timeout = 0;
635
636         /* Enter debug state on reset; restore DEMCR in endreset_event() */
637         retval = mem_ap_write_u32(swjdp, DCB_DEMCR,
638                         TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET);
639         if (retval != ERROR_OK)
640                 return retval;
641
642         /* Request a core-only reset */
643         retval = mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR,
644                         AIRCR_VECTKEY | AIRCR_VECTRESET);
645         if (retval != ERROR_OK)
646                 return retval;
647         target->state = TARGET_RESET;
648
649         /* registers are now invalid */
650         register_cache_invalidate(cortex_m3->armv7m.core_cache);
651
652         while (timeout < 100) {
653                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &dcb_dhcsr);
654                 if (retval == ERROR_OK) {
655                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_DFSR,
656                                         &cortex_m3->nvic_dfsr);
657                         if (retval != ERROR_OK)
658                                 return retval;
659                         if ((dcb_dhcsr & S_HALT)
660                                 && (cortex_m3->nvic_dfsr & DFSR_VCATCH)) {
661                                 LOG_DEBUG("system reset-halted, DHCSR 0x%08x, "
662                                         "DFSR 0x%08x",
663                                         (unsigned) dcb_dhcsr,
664                                         (unsigned) cortex_m3->nvic_dfsr);
665                                 cortex_m3_poll(target);
666                                 /* FIXME restore user's vector catch config */
667                                 return ERROR_OK;
668                         } else
669                                 LOG_DEBUG("waiting for system reset-halt, "
670                                         "DHCSR 0x%08x, %d ms",
671                                         (unsigned) dcb_dhcsr, timeout);
672                 }
673                 timeout++;
674                 alive_sleep(1);
675         }
676
677         return ERROR_OK;
678 }
679
680 static void cortex_m3_enable_breakpoints(struct target *target)
681 {
682         struct breakpoint *breakpoint = target->breakpoints;
683
684         /* set any pending breakpoints */
685         while (breakpoint) {
686                 if (!breakpoint->set)
687                         cortex_m3_set_breakpoint(target, breakpoint);
688                 breakpoint = breakpoint->next;
689         }
690 }
691
692 static int cortex_m3_resume(struct target *target, int current,
693         uint32_t address, int handle_breakpoints, int debug_execution)
694 {
695         struct armv7m_common *armv7m = target_to_armv7m(target);
696         struct breakpoint *breakpoint = NULL;
697         uint32_t resume_pc;
698         struct reg *r;
699
700         if (target->state != TARGET_HALTED) {
701                 LOG_WARNING("target not halted");
702                 return ERROR_TARGET_NOT_HALTED;
703         }
704
705         if (!debug_execution) {
706                 target_free_all_working_areas(target);
707                 cortex_m3_enable_breakpoints(target);
708                 cortex_m3_enable_watchpoints(target);
709         }
710
711         if (debug_execution) {
712                 r = armv7m->core_cache->reg_list + ARMV7M_PRIMASK;
713
714                 /* Disable interrupts */
715                 /* We disable interrupts in the PRIMASK register instead of
716                  * masking with C_MASKINTS.  This is probably the same issue
717                  * as Cortex-M3 Erratum 377493 (fixed in r1p0):  C_MASKINTS
718                  * in parallel with disabled interrupts can cause local faults
719                  * to not be taken.
720                  *
721                  * REVISIT this clearly breaks non-debug execution, since the
722                  * PRIMASK register state isn't saved/restored...  workaround
723                  * by never resuming app code after debug execution.
724                  */
725                 buf_set_u32(r->value, 0, 1, 1);
726                 r->dirty = true;
727                 r->valid = true;
728
729                 /* Make sure we are in Thumb mode */
730                 r = armv7m->core_cache->reg_list + ARMV7M_xPSR;
731                 buf_set_u32(r->value, 24, 1, 1);
732                 r->dirty = true;
733                 r->valid = true;
734         }
735
736         /* current = 1: continue on current pc, otherwise continue at <address> */
737         r = armv7m->arm.pc;
738         if (!current) {
739                 buf_set_u32(r->value, 0, 32, address);
740                 r->dirty = true;
741                 r->valid = true;
742         }
743
744         /* if we halted last time due to a bkpt instruction
745          * then we have to manually step over it, otherwise
746          * the core will break again */
747
748         if (!breakpoint_find(target, buf_get_u32(r->value, 0, 32))
749                 && !debug_execution)
750                 armv7m_maybe_skip_bkpt_inst(target, NULL);
751
752         resume_pc = buf_get_u32(r->value, 0, 32);
753
754         armv7m_restore_context(target);
755
756         /* the front-end may request us not to handle breakpoints */
757         if (handle_breakpoints) {
758                 /* Single step past breakpoint at current address */
759                 breakpoint = breakpoint_find(target, resume_pc);
760                 if (breakpoint) {
761                         LOG_DEBUG("unset breakpoint at 0x%8.8" PRIx32 " (ID: %d)",
762                                 breakpoint->address,
763                                 breakpoint->unique_id);
764                         cortex_m3_unset_breakpoint(target, breakpoint);
765                         cortex_m3_single_step_core(target);
766                         cortex_m3_set_breakpoint(target, breakpoint);
767                 }
768         }
769
770         /* Restart core */
771         cortex_m3_write_debug_halt_mask(target, 0, C_HALT);
772
773         target->debug_reason = DBG_REASON_NOTHALTED;
774
775         /* registers are now invalid */
776         register_cache_invalidate(armv7m->core_cache);
777
778         if (!debug_execution) {
779                 target->state = TARGET_RUNNING;
780                 target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
781                 LOG_DEBUG("target resumed at 0x%" PRIx32 "", resume_pc);
782         } else {
783                 target->state = TARGET_DEBUG_RUNNING;
784                 target_call_event_callbacks(target, TARGET_EVENT_DEBUG_RESUMED);
785                 LOG_DEBUG("target debug resumed at 0x%" PRIx32 "", resume_pc);
786         }
787
788         return ERROR_OK;
789 }
790
791 /* int irqstepcount = 0; */
792 static int cortex_m3_step(struct target *target, int current,
793         uint32_t address, int handle_breakpoints)
794 {
795         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
796         struct armv7m_common *armv7m = &cortex_m3->armv7m;
797         struct adiv5_dap *swjdp = armv7m->arm.dap;
798         struct breakpoint *breakpoint = NULL;
799         struct reg *pc = armv7m->arm.pc;
800         bool bkpt_inst_found = false;
801         int retval;
802         bool isr_timed_out = false;
803
804         if (target->state != TARGET_HALTED) {
805                 LOG_WARNING("target not halted");
806                 return ERROR_TARGET_NOT_HALTED;
807         }
808
809         /* current = 1: continue on current pc, otherwise continue at <address> */
810         if (!current)
811                 buf_set_u32(pc->value, 0, 32, address);
812
813         uint32_t pc_value = buf_get_u32(pc->value, 0, 32);
814
815         /* the front-end may request us not to handle breakpoints */
816         if (handle_breakpoints) {
817                 breakpoint = breakpoint_find(target, pc_value);
818                 if (breakpoint)
819                         cortex_m3_unset_breakpoint(target, breakpoint);
820         }
821
822         armv7m_maybe_skip_bkpt_inst(target, &bkpt_inst_found);
823
824         target->debug_reason = DBG_REASON_SINGLESTEP;
825
826         armv7m_restore_context(target);
827
828         target_call_event_callbacks(target, TARGET_EVENT_RESUMED);
829
830         /* if no bkpt instruction is found at pc then we can perform
831          * a normal step, otherwise we have to manually step over the bkpt
832          * instruction - as such simulate a step */
833         if (bkpt_inst_found == false) {
834                 /* Automatic ISR masking mode off: Just step over the next instruction */
835                 if ((cortex_m3->isrmasking_mode != CORTEX_M3_ISRMASK_AUTO))
836                         cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
837                 else {
838                         /* Process interrupts during stepping in a way they don't interfere
839                          * debugging.
840                          *
841                          * Principle:
842                          *
843                          * Set a temporary break point at the current pc and let the core run
844                          * with interrupts enabled. Pending interrupts get served and we run
845                          * into the breakpoint again afterwards. Then we step over the next
846                          * instruction with interrupts disabled.
847                          *
848                          * If the pending interrupts don't complete within time, we leave the
849                          * core running. This may happen if the interrupts trigger faster
850                          * than the core can process them or the handler doesn't return.
851                          *
852                          * If no more breakpoints are available we simply do a step with
853                          * interrupts enabled.
854                          *
855                          */
856
857                         /* 2012-09-29 ph
858                          *
859                          * If a break point is already set on the lower half word then a break point on
860                          * the upper half word will not break again when the core is restarted. So we
861                          * just step over the instruction with interrupts disabled.
862                          *
863                          * The documentation has no information about this, it was found by observation
864                          * on STM32F1 and STM32F2. Proper explanation welcome. STM32F0 dosen't seem to
865                          * suffer from this problem.
866                          *
867                          * To add some confusion: pc_value has bit 0 always set, while the breakpoint
868                          * address has it always cleared. The former is done to indicate thumb mode
869                          * to gdb.
870                          *
871                          */
872                         if ((pc_value & 0x02) && breakpoint_find(target, pc_value & ~0x03)) {
873                                 LOG_DEBUG("Stepping over next instruction with interrupts disabled");
874                                 cortex_m3_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
875                                 cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
876                                 /* Re-enable interrupts */
877                                 cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
878                         }
879                         else {
880
881                                 /* Set a temporary break point */
882                                 retval = breakpoint_add(target, pc_value, 2, BKPT_TYPE_BY_ADDR(pc_value));
883                                 bool tmp_bp_set = (retval == ERROR_OK);
884
885                                 /* No more breakpoints left, just do a step */
886                                 if (!tmp_bp_set)
887                                         cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
888                                 else {
889                                         /* Start the core */
890                                         LOG_DEBUG("Starting core to serve pending interrupts");
891                                         int64_t t_start = timeval_ms();
892                                         cortex_m3_write_debug_halt_mask(target, 0, C_HALT | C_STEP);
893
894                                         /* Wait for pending handlers to complete or timeout */
895                                         do {
896                                                 retval = mem_ap_read_atomic_u32(swjdp,
897                                                                 DCB_DHCSR,
898                                                                 &cortex_m3->dcb_dhcsr);
899                                                 if (retval != ERROR_OK) {
900                                                         target->state = TARGET_UNKNOWN;
901                                                         return retval;
902                                                 }
903                                                 isr_timed_out = ((timeval_ms() - t_start) > 500);
904                                         } while (!((cortex_m3->dcb_dhcsr & S_HALT) || isr_timed_out));
905
906                                         /* Remove the temporary breakpoint */
907                                         breakpoint_remove(target, pc_value);
908
909                                         if (isr_timed_out) {
910                                                 LOG_DEBUG("Interrupt handlers didn't complete within time, "
911                                                         "leaving target running");
912                                         } else {
913                                                 /* Step over next instruction with interrupts disabled */
914                                                 cortex_m3_write_debug_halt_mask(target,
915                                                         C_HALT | C_MASKINTS,
916                                                         0);
917                                                 cortex_m3_write_debug_halt_mask(target, C_STEP, C_HALT);
918                                                 /* Re-enable interrupts */
919                                                 cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
920                                         }
921                                 }
922                         }
923                 }
924         }
925
926         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
927         if (retval != ERROR_OK)
928                 return retval;
929
930         /* registers are now invalid */
931         register_cache_invalidate(cortex_m3->armv7m.core_cache);
932
933         if (breakpoint)
934                 cortex_m3_set_breakpoint(target, breakpoint);
935
936         if (isr_timed_out) {
937                 /* Leave the core running. The user has to stop execution manually. */
938                 target->debug_reason = DBG_REASON_NOTHALTED;
939                 target->state = TARGET_RUNNING;
940                 return ERROR_OK;
941         }
942
943         LOG_DEBUG("target stepped dcb_dhcsr = 0x%" PRIx32
944                 " nvic_icsr = 0x%" PRIx32,
945                 cortex_m3->dcb_dhcsr, cortex_m3->nvic_icsr);
946
947         retval = cortex_m3_debug_entry(target);
948         if (retval != ERROR_OK)
949                 return retval;
950         target_call_event_callbacks(target, TARGET_EVENT_HALTED);
951
952         LOG_DEBUG("target stepped dcb_dhcsr = 0x%" PRIx32
953                 " nvic_icsr = 0x%" PRIx32,
954                 cortex_m3->dcb_dhcsr, cortex_m3->nvic_icsr);
955
956         return ERROR_OK;
957 }
958
959 static int cortex_m3_assert_reset(struct target *target)
960 {
961         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
962         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
963         enum cortex_m3_soft_reset_config reset_config = cortex_m3->soft_reset_config;
964
965         LOG_DEBUG("target->state: %s",
966                 target_state_name(target));
967
968         enum reset_types jtag_reset_config = jtag_get_reset_config();
969
970         if (target_has_event_action(target, TARGET_EVENT_RESET_ASSERT)) {
971                 /* allow scripts to override the reset event */
972
973                 target_handle_event(target, TARGET_EVENT_RESET_ASSERT);
974                 register_cache_invalidate(cortex_m3->armv7m.core_cache);
975                 target->state = TARGET_RESET;
976
977                 return ERROR_OK;
978         }
979
980         /* some cores support connecting while srst is asserted
981          * use that mode is it has been configured */
982
983         bool srst_asserted = false;
984
985         if (jtag_reset_config & RESET_SRST_NO_GATING) {
986                 adapter_assert_reset();
987                 srst_asserted = true;
988         }
989
990         /* Enable debug requests */
991         int retval;
992         retval = mem_ap_read_atomic_u32(swjdp, DCB_DHCSR, &cortex_m3->dcb_dhcsr);
993         if (retval != ERROR_OK)
994                 return retval;
995         if (!(cortex_m3->dcb_dhcsr & C_DEBUGEN)) {
996                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_DEBUGEN);
997                 if (retval != ERROR_OK)
998                         return retval;
999         }
1000
1001         /* If the processor is sleeping in a WFI or WFE instruction, the
1002          * C_HALT bit must be asserted to regain control */
1003         if (cortex_m3->dcb_dhcsr & S_SLEEP) {
1004                 retval = mem_ap_write_u32(swjdp, DCB_DHCSR, DBGKEY | C_HALT | C_DEBUGEN);
1005                 if (retval != ERROR_OK)
1006                         return retval;
1007         }
1008
1009         retval = mem_ap_write_u32(swjdp, DCB_DCRDR, 0);
1010         if (retval != ERROR_OK)
1011                 return retval;
1012
1013         if (!target->reset_halt) {
1014                 /* Set/Clear C_MASKINTS in a separate operation */
1015                 if (cortex_m3->dcb_dhcsr & C_MASKINTS) {
1016                         retval = mem_ap_write_atomic_u32(swjdp, DCB_DHCSR,
1017                                         DBGKEY | C_DEBUGEN | C_HALT);
1018                         if (retval != ERROR_OK)
1019                                 return retval;
1020                 }
1021
1022                 /* clear any debug flags before resuming */
1023                 cortex_m3_clear_halt(target);
1024
1025                 /* clear C_HALT in dhcsr reg */
1026                 cortex_m3_write_debug_halt_mask(target, 0, C_HALT);
1027         } else {
1028                 /* Halt in debug on reset; endreset_event() restores DEMCR.
1029                  *
1030                  * REVISIT catching BUSERR presumably helps to defend against
1031                  * bad vector table entries.  Should this include MMERR or
1032                  * other flags too?
1033                  */
1034                 retval = mem_ap_write_atomic_u32(swjdp, DCB_DEMCR,
1035                                 TRCENA | VC_HARDERR | VC_BUSERR | VC_CORERESET);
1036                 if (retval != ERROR_OK)
1037                         return retval;
1038         }
1039
1040         if (jtag_reset_config & RESET_HAS_SRST) {
1041                 /* default to asserting srst */
1042                 if (!srst_asserted)
1043                         adapter_assert_reset();
1044         } else {
1045                 /* Use a standard Cortex-M3 software reset mechanism.
1046                  * We default to using VECRESET as it is supported on all current cores.
1047                  * This has the disadvantage of not resetting the peripherals, so a
1048                  * reset-init event handler is needed to perform any peripheral resets.
1049                  */
1050                 retval = mem_ap_write_atomic_u32(swjdp, NVIC_AIRCR,
1051                                 AIRCR_VECTKEY | ((reset_config == CORTEX_M3_RESET_SYSRESETREQ)
1052                                 ? AIRCR_SYSRESETREQ : AIRCR_VECTRESET));
1053                 if (retval != ERROR_OK)
1054                         return retval;
1055
1056                 LOG_DEBUG("Using Cortex-M3 %s", (reset_config == CORTEX_M3_RESET_SYSRESETREQ)
1057                         ? "SYSRESETREQ" : "VECTRESET");
1058
1059                 if (reset_config == CORTEX_M3_RESET_VECTRESET) {
1060                         LOG_WARNING("Only resetting the Cortex-M3 core, use a reset-init event "
1061                                 "handler to reset any peripherals or configure hardware srst support.");
1062                 }
1063
1064                 {
1065                         /* I do not know why this is necessary, but it
1066                          * fixes strange effects (step/resume cause NMI
1067                          * after reset) on LM3S6918 -- Michael Schwingen
1068                          */
1069                         uint32_t tmp;
1070                         retval = mem_ap_read_atomic_u32(swjdp, NVIC_AIRCR, &tmp);
1071                         if (retval != ERROR_OK)
1072                                 return retval;
1073                 }
1074         }
1075
1076         target->state = TARGET_RESET;
1077         jtag_add_sleep(50000);
1078
1079         register_cache_invalidate(cortex_m3->armv7m.core_cache);
1080
1081         if (target->reset_halt) {
1082                 retval = target_halt(target);
1083                 if (retval != ERROR_OK)
1084                         return retval;
1085         }
1086
1087         return ERROR_OK;
1088 }
1089
1090 static int cortex_m3_deassert_reset(struct target *target)
1091 {
1092         LOG_DEBUG("target->state: %s",
1093                 target_state_name(target));
1094
1095         /* deassert reset lines */
1096         adapter_deassert_reset();
1097
1098         return ERROR_OK;
1099 }
1100
1101 int cortex_m3_set_breakpoint(struct target *target, struct breakpoint *breakpoint)
1102 {
1103         int retval;
1104         int fp_num = 0;
1105         uint32_t hilo;
1106         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1107         struct cortex_m3_fp_comparator *comparator_list = cortex_m3->fp_comparator_list;
1108
1109         if (breakpoint->set) {
1110                 LOG_WARNING("breakpoint (BPID: %d) already set", breakpoint->unique_id);
1111                 return ERROR_OK;
1112         }
1113
1114         if (cortex_m3->auto_bp_type)
1115                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1116
1117         if (breakpoint->type == BKPT_HARD) {
1118                 while (comparator_list[fp_num].used && (fp_num < cortex_m3->fp_num_code))
1119                         fp_num++;
1120                 if (fp_num >= cortex_m3->fp_num_code) {
1121                         LOG_ERROR("Can not find free FPB Comparator!");
1122                         return ERROR_FAIL;
1123                 }
1124                 breakpoint->set = fp_num + 1;
1125                 hilo = (breakpoint->address & 0x2) ? FPCR_REPLACE_BKPT_HIGH : FPCR_REPLACE_BKPT_LOW;
1126                 comparator_list[fp_num].used = 1;
1127                 comparator_list[fp_num].fpcr_value = (breakpoint->address & 0x1FFFFFFC) | hilo | 1;
1128                 target_write_u32(target, comparator_list[fp_num].fpcr_address,
1129                         comparator_list[fp_num].fpcr_value);
1130                 LOG_DEBUG("fpc_num %i fpcr_value 0x%" PRIx32 "",
1131                         fp_num,
1132                         comparator_list[fp_num].fpcr_value);
1133                 if (!cortex_m3->fpb_enabled) {
1134                         LOG_DEBUG("FPB wasn't enabled, do it now");
1135                         target_write_u32(target, FP_CTRL, 3);
1136                 }
1137         } else if (breakpoint->type == BKPT_SOFT) {
1138                 uint8_t code[4];
1139
1140                 /* NOTE: on ARMv6-M and ARMv7-M, BKPT(0xab) is used for
1141                  * semihosting; don't use that.  Otherwise the BKPT
1142                  * parameter is arbitrary.
1143                  */
1144                 buf_set_u32(code, 0, 32, ARMV5_T_BKPT(0x11));
1145                 retval = target_read_memory(target,
1146                                 breakpoint->address & 0xFFFFFFFE,
1147                                 breakpoint->length, 1,
1148                                 breakpoint->orig_instr);
1149                 if (retval != ERROR_OK)
1150                         return retval;
1151                 retval = target_write_memory(target,
1152                                 breakpoint->address & 0xFFFFFFFE,
1153                                 breakpoint->length, 1,
1154                                 code);
1155                 if (retval != ERROR_OK)
1156                         return retval;
1157                 breakpoint->set = true;
1158         }
1159
1160         LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)",
1161                 breakpoint->unique_id,
1162                 (int)(breakpoint->type),
1163                 breakpoint->address,
1164                 breakpoint->length,
1165                 breakpoint->set);
1166
1167         return ERROR_OK;
1168 }
1169
1170 int cortex_m3_unset_breakpoint(struct target *target, struct breakpoint *breakpoint)
1171 {
1172         int retval;
1173         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1174         struct cortex_m3_fp_comparator *comparator_list = cortex_m3->fp_comparator_list;
1175
1176         if (!breakpoint->set) {
1177                 LOG_WARNING("breakpoint not set");
1178                 return ERROR_OK;
1179         }
1180
1181         LOG_DEBUG("BPID: %d, Type: %d, Address: 0x%08" PRIx32 " Length: %d (set=%d)",
1182                 breakpoint->unique_id,
1183                 (int)(breakpoint->type),
1184                 breakpoint->address,
1185                 breakpoint->length,
1186                 breakpoint->set);
1187
1188         if (breakpoint->type == BKPT_HARD) {
1189                 int fp_num = breakpoint->set - 1;
1190                 if ((fp_num < 0) || (fp_num >= cortex_m3->fp_num_code)) {
1191                         LOG_DEBUG("Invalid FP Comparator number in breakpoint");
1192                         return ERROR_OK;
1193                 }
1194                 comparator_list[fp_num].used = 0;
1195                 comparator_list[fp_num].fpcr_value = 0;
1196                 target_write_u32(target, comparator_list[fp_num].fpcr_address,
1197                         comparator_list[fp_num].fpcr_value);
1198         } else {
1199                 /* restore original instruction (kept in target endianness) */
1200                 if (breakpoint->length == 4) {
1201                         retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 4, 1,
1202                                         breakpoint->orig_instr);
1203                         if (retval != ERROR_OK)
1204                                 return retval;
1205                 } else {
1206                         retval = target_write_memory(target, breakpoint->address & 0xFFFFFFFE, 2, 1,
1207                                         breakpoint->orig_instr);
1208                         if (retval != ERROR_OK)
1209                                 return retval;
1210                 }
1211         }
1212         breakpoint->set = false;
1213
1214         return ERROR_OK;
1215 }
1216
1217 int cortex_m3_add_breakpoint(struct target *target, struct breakpoint *breakpoint)
1218 {
1219         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1220
1221         if (cortex_m3->auto_bp_type) {
1222                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1223 #ifdef ARMV7_GDB_HACKS
1224                 if (breakpoint->length != 2) {
1225                         /* XXX Hack: Replace all breakpoints with length != 2 with
1226                          * a hardware breakpoint. */
1227                         breakpoint->type = BKPT_HARD;
1228                         breakpoint->length = 2;
1229                 }
1230 #endif
1231         }
1232
1233         if (breakpoint->type != BKPT_TYPE_BY_ADDR(breakpoint->address)) {
1234                 if (breakpoint->type == BKPT_HARD) {
1235                         LOG_INFO("flash patch comparator requested outside code memory region");
1236                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1237                 }
1238
1239                 if (breakpoint->type == BKPT_SOFT) {
1240                         LOG_INFO("soft breakpoint requested in code (flash) memory region");
1241                         return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1242                 }
1243         }
1244
1245         if ((breakpoint->type == BKPT_HARD) && (cortex_m3->fp_code_available < 1)) {
1246                 LOG_INFO("no flash patch comparator unit available for hardware breakpoint");
1247                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1248         }
1249
1250         if ((breakpoint->length != 2)) {
1251                 LOG_INFO("only breakpoints of two bytes length supported");
1252                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1253         }
1254
1255         if (breakpoint->type == BKPT_HARD)
1256                 cortex_m3->fp_code_available--;
1257
1258         return cortex_m3_set_breakpoint(target, breakpoint);
1259 }
1260
1261 int cortex_m3_remove_breakpoint(struct target *target, struct breakpoint *breakpoint)
1262 {
1263         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1264
1265         /* REVISIT why check? FBP can be updated with core running ... */
1266         if (target->state != TARGET_HALTED) {
1267                 LOG_WARNING("target not halted");
1268                 return ERROR_TARGET_NOT_HALTED;
1269         }
1270
1271         if (cortex_m3->auto_bp_type)
1272                 breakpoint->type = BKPT_TYPE_BY_ADDR(breakpoint->address);
1273
1274         if (breakpoint->set)
1275                 cortex_m3_unset_breakpoint(target, breakpoint);
1276
1277         if (breakpoint->type == BKPT_HARD)
1278                 cortex_m3->fp_code_available++;
1279
1280         return ERROR_OK;
1281 }
1282
1283 int cortex_m3_set_watchpoint(struct target *target, struct watchpoint *watchpoint)
1284 {
1285         int dwt_num = 0;
1286         uint32_t mask, temp;
1287         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1288
1289         /* watchpoint params were validated earlier */
1290         mask = 0;
1291         temp = watchpoint->length;
1292         while (temp) {
1293                 temp >>= 1;
1294                 mask++;
1295         }
1296         mask--;
1297
1298         /* REVISIT Don't fully trust these "not used" records ... users
1299          * may set up breakpoints by hand, e.g. dual-address data value
1300          * watchpoint using comparator #1; comparator #0 matching cycle
1301          * count; send data trace info through ITM and TPIU; etc
1302          */
1303         struct cortex_m3_dwt_comparator *comparator;
1304
1305         for (comparator = cortex_m3->dwt_comparator_list;
1306                 comparator->used && dwt_num < cortex_m3->dwt_num_comp;
1307                 comparator++, dwt_num++)
1308                 continue;
1309         if (dwt_num >= cortex_m3->dwt_num_comp) {
1310                 LOG_ERROR("Can not find free DWT Comparator");
1311                 return ERROR_FAIL;
1312         }
1313         comparator->used = 1;
1314         watchpoint->set = dwt_num + 1;
1315
1316         comparator->comp = watchpoint->address;
1317         target_write_u32(target, comparator->dwt_comparator_address + 0,
1318                 comparator->comp);
1319
1320         comparator->mask = mask;
1321         target_write_u32(target, comparator->dwt_comparator_address + 4,
1322                 comparator->mask);
1323
1324         switch (watchpoint->rw) {
1325                 case WPT_READ:
1326                         comparator->function = 5;
1327                         break;
1328                 case WPT_WRITE:
1329                         comparator->function = 6;
1330                         break;
1331                 case WPT_ACCESS:
1332                         comparator->function = 7;
1333                         break;
1334         }
1335         target_write_u32(target, comparator->dwt_comparator_address + 8,
1336                 comparator->function);
1337
1338         LOG_DEBUG("Watchpoint (ID %d) DWT%d 0x%08x 0x%x 0x%05x",
1339                 watchpoint->unique_id, dwt_num,
1340                 (unsigned) comparator->comp,
1341                 (unsigned) comparator->mask,
1342                 (unsigned) comparator->function);
1343         return ERROR_OK;
1344 }
1345
1346 int cortex_m3_unset_watchpoint(struct target *target, struct watchpoint *watchpoint)
1347 {
1348         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1349         struct cortex_m3_dwt_comparator *comparator;
1350         int dwt_num;
1351
1352         if (!watchpoint->set) {
1353                 LOG_WARNING("watchpoint (wpid: %d) not set",
1354                         watchpoint->unique_id);
1355                 return ERROR_OK;
1356         }
1357
1358         dwt_num = watchpoint->set - 1;
1359
1360         LOG_DEBUG("Watchpoint (ID %d) DWT%d address: 0x%08x clear",
1361                 watchpoint->unique_id, dwt_num,
1362                 (unsigned) watchpoint->address);
1363
1364         if ((dwt_num < 0) || (dwt_num >= cortex_m3->dwt_num_comp)) {
1365                 LOG_DEBUG("Invalid DWT Comparator number in watchpoint");
1366                 return ERROR_OK;
1367         }
1368
1369         comparator = cortex_m3->dwt_comparator_list + dwt_num;
1370         comparator->used = 0;
1371         comparator->function = 0;
1372         target_write_u32(target, comparator->dwt_comparator_address + 8,
1373                 comparator->function);
1374
1375         watchpoint->set = false;
1376
1377         return ERROR_OK;
1378 }
1379
1380 int cortex_m3_add_watchpoint(struct target *target, struct watchpoint *watchpoint)
1381 {
1382         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1383
1384         if (cortex_m3->dwt_comp_available < 1) {
1385                 LOG_DEBUG("no comparators?");
1386                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1387         }
1388
1389         /* hardware doesn't support data value masking */
1390         if (watchpoint->mask != ~(uint32_t)0) {
1391                 LOG_DEBUG("watchpoint value masks not supported");
1392                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1393         }
1394
1395         /* hardware allows address masks of up to 32K */
1396         unsigned mask;
1397
1398         for (mask = 0; mask < 16; mask++) {
1399                 if ((1u << mask) == watchpoint->length)
1400                         break;
1401         }
1402         if (mask == 16) {
1403                 LOG_DEBUG("unsupported watchpoint length");
1404                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1405         }
1406         if (watchpoint->address & ((1 << mask) - 1)) {
1407                 LOG_DEBUG("watchpoint address is unaligned");
1408                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1409         }
1410
1411         /* Caller doesn't seem to be able to describe watching for data
1412          * values of zero; that flags "no value".
1413          *
1414          * REVISIT This DWT may well be able to watch for specific data
1415          * values.  Requires comparator #1 to set DATAVMATCH and match
1416          * the data, and another comparator (DATAVADDR0) matching addr.
1417          */
1418         if (watchpoint->value) {
1419                 LOG_DEBUG("data value watchpoint not YET supported");
1420                 return ERROR_TARGET_RESOURCE_NOT_AVAILABLE;
1421         }
1422
1423         cortex_m3->dwt_comp_available--;
1424         LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
1425
1426         return ERROR_OK;
1427 }
1428
1429 int cortex_m3_remove_watchpoint(struct target *target, struct watchpoint *watchpoint)
1430 {
1431         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1432
1433         /* REVISIT why check? DWT can be updated with core running ... */
1434         if (target->state != TARGET_HALTED) {
1435                 LOG_WARNING("target not halted");
1436                 return ERROR_TARGET_NOT_HALTED;
1437         }
1438
1439         if (watchpoint->set)
1440                 cortex_m3_unset_watchpoint(target, watchpoint);
1441
1442         cortex_m3->dwt_comp_available++;
1443         LOG_DEBUG("dwt_comp_available: %d", cortex_m3->dwt_comp_available);
1444
1445         return ERROR_OK;
1446 }
1447
1448 void cortex_m3_enable_watchpoints(struct target *target)
1449 {
1450         struct watchpoint *watchpoint = target->watchpoints;
1451
1452         /* set any pending watchpoints */
1453         while (watchpoint) {
1454                 if (!watchpoint->set)
1455                         cortex_m3_set_watchpoint(target, watchpoint);
1456                 watchpoint = watchpoint->next;
1457         }
1458 }
1459
1460 static int cortex_m3_load_core_reg_u32(struct target *target,
1461         enum armv7m_regtype type, uint32_t num, uint32_t *value)
1462 {
1463         int retval;
1464         struct armv7m_common *armv7m = target_to_armv7m(target);
1465         struct adiv5_dap *swjdp = armv7m->arm.dap;
1466
1467         /* NOTE:  we "know" here that the register identifiers used
1468          * in the v7m header match the Cortex-M3 Debug Core Register
1469          * Selector values for R0..R15, xPSR, MSP, and PSP.
1470          */
1471         switch (num) {
1472                 case 0 ... 18:
1473                         /* read a normal core register */
1474                         retval = cortexm3_dap_read_coreregister_u32(swjdp, value, num);
1475
1476                         if (retval != ERROR_OK) {
1477                                 LOG_ERROR("JTAG failure %i", retval);
1478                                 return ERROR_JTAG_DEVICE_ERROR;
1479                         }
1480                         LOG_DEBUG("load from core reg %i  value 0x%" PRIx32 "", (int)num, *value);
1481                         break;
1482
1483                 case ARMV7M_PRIMASK:
1484                 case ARMV7M_BASEPRI:
1485                 case ARMV7M_FAULTMASK:
1486                 case ARMV7M_CONTROL:
1487                         /* Cortex-M3 packages these four registers as bitfields
1488                          * in one Debug Core register.  So say r0 and r2 docs;
1489                          * it was removed from r1 docs, but still works.
1490                          */
1491                         cortexm3_dap_read_coreregister_u32(swjdp, value, 20);
1492
1493                         switch (num) {
1494                                 case ARMV7M_PRIMASK:
1495                                         *value = buf_get_u32((uint8_t *)value, 0, 1);
1496                                         break;
1497
1498                                 case ARMV7M_BASEPRI:
1499                                         *value = buf_get_u32((uint8_t *)value, 8, 8);
1500                                         break;
1501
1502                                 case ARMV7M_FAULTMASK:
1503                                         *value = buf_get_u32((uint8_t *)value, 16, 1);
1504                                         break;
1505
1506                                 case ARMV7M_CONTROL:
1507                                         *value = buf_get_u32((uint8_t *)value, 24, 2);
1508                                         break;
1509                         }
1510
1511                         LOG_DEBUG("load from special reg %i value 0x%" PRIx32 "", (int)num, *value);
1512                         break;
1513
1514                 default:
1515                         return ERROR_COMMAND_SYNTAX_ERROR;
1516         }
1517
1518         return ERROR_OK;
1519 }
1520
1521 static int cortex_m3_store_core_reg_u32(struct target *target,
1522         enum armv7m_regtype type, uint32_t num, uint32_t value)
1523 {
1524         int retval;
1525         uint32_t reg;
1526         struct armv7m_common *armv7m = target_to_armv7m(target);
1527         struct adiv5_dap *swjdp = armv7m->arm.dap;
1528
1529 #ifdef ARMV7_GDB_HACKS
1530         /* If the LR register is being modified, make sure it will put us
1531          * in "thumb" mode, or an INVSTATE exception will occur. This is a
1532          * hack to deal with the fact that gdb will sometimes "forge"
1533          * return addresses, and doesn't set the LSB correctly (i.e., when
1534          * printing expressions containing function calls, it sets LR = 0.)
1535          * Valid exception return codes have bit 0 set too.
1536          */
1537         if (num == ARMV7M_R14)
1538                 value |= 0x01;
1539 #endif
1540
1541         /* NOTE:  we "know" here that the register identifiers used
1542          * in the v7m header match the Cortex-M3 Debug Core Register
1543          * Selector values for R0..R15, xPSR, MSP, and PSP.
1544          */
1545         switch (num) {
1546                 case 0 ... 18:
1547                         retval = cortexm3_dap_write_coreregister_u32(swjdp, value, num);
1548                         if (retval != ERROR_OK) {
1549                                 struct reg *r;
1550
1551                                 LOG_ERROR("JTAG failure");
1552                                 r = armv7m->core_cache->reg_list + num;
1553                                 r->dirty = r->valid;
1554                                 return ERROR_JTAG_DEVICE_ERROR;
1555                         }
1556                         LOG_DEBUG("write core reg %i value 0x%" PRIx32 "", (int)num, value);
1557                         break;
1558
1559                 case ARMV7M_PRIMASK:
1560                 case ARMV7M_BASEPRI:
1561                 case ARMV7M_FAULTMASK:
1562                 case ARMV7M_CONTROL:
1563                         /* Cortex-M3 packages these four registers as bitfields
1564                          * in one Debug Core register.  So say r0 and r2 docs;
1565                          * it was removed from r1 docs, but still works.
1566                          */
1567                         cortexm3_dap_read_coreregister_u32(swjdp, &reg, 20);
1568
1569                         switch (num) {
1570                                 case ARMV7M_PRIMASK:
1571                                         buf_set_u32((uint8_t *)&reg, 0, 1, value);
1572                                         break;
1573
1574                                 case ARMV7M_BASEPRI:
1575                                         buf_set_u32((uint8_t *)&reg, 8, 8, value);
1576                                         break;
1577
1578                                 case ARMV7M_FAULTMASK:
1579                                         buf_set_u32((uint8_t *)&reg, 16, 1, value);
1580                                         break;
1581
1582                                 case ARMV7M_CONTROL:
1583                                         buf_set_u32((uint8_t *)&reg, 24, 2, value);
1584                                         break;
1585                         }
1586
1587                         cortexm3_dap_write_coreregister_u32(swjdp, reg, 20);
1588
1589                         LOG_DEBUG("write special reg %i value 0x%" PRIx32 " ", (int)num, value);
1590                         break;
1591
1592                 default:
1593                         return ERROR_COMMAND_SYNTAX_ERROR;
1594         }
1595
1596         return ERROR_OK;
1597 }
1598
1599 static int cortex_m3_read_memory(struct target *target, uint32_t address,
1600         uint32_t size, uint32_t count, uint8_t *buffer)
1601 {
1602         struct armv7m_common *armv7m = target_to_armv7m(target);
1603         struct adiv5_dap *swjdp = armv7m->arm.dap;
1604         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1605
1606         if (armv7m->arm.is_armv6m) {
1607                 /* armv6m does not handle unaligned memory access */
1608                 if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
1609                         return ERROR_TARGET_UNALIGNED_ACCESS;
1610         }
1611
1612         /* cortex_m3 handles unaligned memory access */
1613         if (count && buffer) {
1614                 switch (size) {
1615                         case 4:
1616                                 retval = mem_ap_read_buf_u32(swjdp, buffer, 4 * count, address);
1617                                 break;
1618                         case 2:
1619                                 retval = mem_ap_read_buf_u16(swjdp, buffer, 2 * count, address);
1620                                 break;
1621                         case 1:
1622                                 retval = mem_ap_read_buf_u8(swjdp, buffer, count, address);
1623                                 break;
1624                 }
1625         }
1626
1627         return retval;
1628 }
1629
1630 static int cortex_m3_write_memory(struct target *target, uint32_t address,
1631         uint32_t size, uint32_t count, const uint8_t *buffer)
1632 {
1633         struct armv7m_common *armv7m = target_to_armv7m(target);
1634         struct adiv5_dap *swjdp = armv7m->arm.dap;
1635         int retval = ERROR_COMMAND_SYNTAX_ERROR;
1636
1637         if (armv7m->arm.is_armv6m) {
1638                 /* armv6m does not handle unaligned memory access */
1639                 if (((size == 4) && (address & 0x3u)) || ((size == 2) && (address & 0x1u)))
1640                         return ERROR_TARGET_UNALIGNED_ACCESS;
1641         }
1642
1643         if (count && buffer) {
1644                 switch (size) {
1645                         case 4:
1646                                 retval = mem_ap_write_buf_u32(swjdp, buffer, 4 * count, address);
1647                                 break;
1648                         case 2:
1649                                 retval = mem_ap_write_buf_u16(swjdp, buffer, 2 * count, address);
1650                                 break;
1651                         case 1:
1652                                 retval = mem_ap_write_buf_u8(swjdp, buffer, count, address);
1653                                 break;
1654                 }
1655         }
1656
1657         return retval;
1658 }
1659
1660 static int cortex_m3_bulk_write_memory(struct target *target, uint32_t address,
1661         uint32_t count, const uint8_t *buffer)
1662 {
1663         return cortex_m3_write_memory(target, address, 4, count, buffer);
1664 }
1665
1666 static int cortex_m3_init_target(struct command_context *cmd_ctx,
1667         struct target *target)
1668 {
1669         armv7m_build_reg_cache(target);
1670         return ERROR_OK;
1671 }
1672
1673 /* REVISIT cache valid/dirty bits are unmaintained.  We could set "valid"
1674  * on r/w if the core is not running, and clear on resume or reset ... or
1675  * at least, in a post_restore_context() method.
1676  */
1677
1678 struct dwt_reg_state {
1679         struct target *target;
1680         uint32_t addr;
1681         uint32_t value;         /* scratch/cache */
1682 };
1683
1684 static int cortex_m3_dwt_get_reg(struct reg *reg)
1685 {
1686         struct dwt_reg_state *state = reg->arch_info;
1687
1688         return target_read_u32(state->target, state->addr, &state->value);
1689 }
1690
1691 static int cortex_m3_dwt_set_reg(struct reg *reg, uint8_t *buf)
1692 {
1693         struct dwt_reg_state *state = reg->arch_info;
1694
1695         return target_write_u32(state->target, state->addr,
1696                         buf_get_u32(buf, 0, reg->size));
1697 }
1698
1699 struct dwt_reg {
1700         uint32_t addr;
1701         char *name;
1702         unsigned size;
1703 };
1704
1705 static struct dwt_reg dwt_base_regs[] = {
1706         { DWT_CTRL, "dwt_ctrl", 32, },
1707         /* NOTE that Erratum 532314 (fixed r2p0) affects CYCCNT:  it wrongly
1708          * increments while the core is asleep.
1709          */
1710         { DWT_CYCCNT, "dwt_cyccnt", 32, },
1711         /* plus some 8 bit counters, useful for profiling with TPIU */
1712 };
1713
1714 static struct dwt_reg dwt_comp[] = {
1715 #define DWT_COMPARATOR(i) \
1716                 { DWT_COMP0 + 0x10 * (i), "dwt_" #i "_comp", 32, }, \
1717                 { DWT_MASK0 + 0x10 * (i), "dwt_" #i "_mask", 4, }, \
1718                 { DWT_FUNCTION0 + 0x10 * (i), "dwt_" #i "_function", 32, }
1719         DWT_COMPARATOR(0),
1720         DWT_COMPARATOR(1),
1721         DWT_COMPARATOR(2),
1722         DWT_COMPARATOR(3),
1723 #undef DWT_COMPARATOR
1724 };
1725
1726 static const struct reg_arch_type dwt_reg_type = {
1727         .get = cortex_m3_dwt_get_reg,
1728         .set = cortex_m3_dwt_set_reg,
1729 };
1730
1731 static void cortex_m3_dwt_addreg(struct target *t, struct reg *r, struct dwt_reg *d)
1732 {
1733         struct dwt_reg_state *state;
1734
1735         state = calloc(1, sizeof *state);
1736         if (!state)
1737                 return;
1738         state->addr = d->addr;
1739         state->target = t;
1740
1741         r->name = d->name;
1742         r->size = d->size;
1743         r->value = &state->value;
1744         r->arch_info = state;
1745         r->type = &dwt_reg_type;
1746 }
1747
1748 void cortex_m3_dwt_setup(struct cortex_m3_common *cm3, struct target *target)
1749 {
1750         uint32_t dwtcr;
1751         struct reg_cache *cache;
1752         struct cortex_m3_dwt_comparator *comparator;
1753         int reg, i;
1754
1755         target_read_u32(target, DWT_CTRL, &dwtcr);
1756         if (!dwtcr) {
1757                 LOG_DEBUG("no DWT");
1758                 return;
1759         }
1760
1761         cm3->dwt_num_comp = (dwtcr >> 28) & 0xF;
1762         cm3->dwt_comp_available = cm3->dwt_num_comp;
1763         cm3->dwt_comparator_list = calloc(cm3->dwt_num_comp,
1764                         sizeof(struct cortex_m3_dwt_comparator));
1765         if (!cm3->dwt_comparator_list) {
1766 fail0:
1767                 cm3->dwt_num_comp = 0;
1768                 LOG_ERROR("out of mem");
1769                 return;
1770         }
1771
1772         cache = calloc(1, sizeof *cache);
1773         if (!cache) {
1774 fail1:
1775                 free(cm3->dwt_comparator_list);
1776                 goto fail0;
1777         }
1778         cache->name = "cortex-m3 dwt registers";
1779         cache->num_regs = 2 + cm3->dwt_num_comp * 3;
1780         cache->reg_list = calloc(cache->num_regs, sizeof *cache->reg_list);
1781         if (!cache->reg_list) {
1782                 free(cache);
1783                 goto fail1;
1784         }
1785
1786         for (reg = 0; reg < 2; reg++)
1787                 cortex_m3_dwt_addreg(target, cache->reg_list + reg,
1788                         dwt_base_regs + reg);
1789
1790         comparator = cm3->dwt_comparator_list;
1791         for (i = 0; i < cm3->dwt_num_comp; i++, comparator++) {
1792                 int j;
1793
1794                 comparator->dwt_comparator_address = DWT_COMP0 + 0x10 * i;
1795                 for (j = 0; j < 3; j++, reg++)
1796                         cortex_m3_dwt_addreg(target, cache->reg_list + reg,
1797                                 dwt_comp + 3 * i + j);
1798         }
1799
1800         *register_get_last_cache_p(&target->reg_cache) = cache;
1801         cm3->dwt_cache = cache;
1802
1803         LOG_DEBUG("DWT dwtcr 0x%" PRIx32 ", comp %d, watch%s",
1804                 dwtcr, cm3->dwt_num_comp,
1805                 (dwtcr & (0xf << 24)) ? " only" : "/trigger");
1806
1807         /* REVISIT:  if num_comp > 1, check whether comparator #1 can
1808          * implement single-address data value watchpoints ... so we
1809          * won't need to check it later, when asked to set one up.
1810          */
1811 }
1812
1813 #define MVFR0 0xe000ef40
1814 #define MVFR1 0xe000ef44
1815
1816 #define MVFR0_DEFAULT_M4 0x10110021
1817 #define MVFR1_DEFAULT_M4 0x11000011
1818
1819 int cortex_m3_examine(struct target *target)
1820 {
1821         int retval;
1822         uint32_t cpuid, fpcr, mvfr0, mvfr1;
1823         int i;
1824         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
1825         struct adiv5_dap *swjdp = cortex_m3->armv7m.arm.dap;
1826         struct armv7m_common *armv7m = target_to_armv7m(target);
1827
1828         /* stlink shares the examine handler but does not support
1829          * all its calls */
1830         if (!armv7m->stlink) {
1831                 retval = ahbap_debugport_init(swjdp);
1832                 if (retval != ERROR_OK)
1833                         return retval;
1834         }
1835
1836         if (!target_was_examined(target)) {
1837                 target_set_examined(target);
1838
1839                 /* Read from Device Identification Registers */
1840                 retval = target_read_u32(target, CPUID, &cpuid);
1841                 if (retval != ERROR_OK)
1842                         return retval;
1843
1844                 /* Get CPU Type */
1845                 i = (cpuid >> 4) & 0xf;
1846
1847                 LOG_DEBUG("Cortex-M%d r%" PRId8 "p%" PRId8 " processor detected",
1848                                 i, (uint8_t)((cpuid >> 20) & 0xf), (uint8_t)((cpuid >> 0) & 0xf));
1849                 LOG_DEBUG("cpuid: 0x%8.8" PRIx32 "", cpuid);
1850
1851                 /* test for floating point feature on cortex-m4 */
1852                 if (i == 4) {
1853                         target_read_u32(target, MVFR0, &mvfr0);
1854                         target_read_u32(target, MVFR1, &mvfr1);
1855
1856                         if ((mvfr0 == MVFR0_DEFAULT_M4) && (mvfr1 == MVFR1_DEFAULT_M4)) {
1857                                 LOG_DEBUG("Cortex-M%d floating point feature FPv4_SP found", i);
1858                                 armv7m->fp_feature = FPv4_SP;
1859                         }
1860                 } else if (i == 0) {
1861                         /* Cortex-M0 does not support unaligned memory access */
1862                         armv7m->arm.is_armv6m = true;
1863                 }
1864
1865                 if (i == 4 || i == 3) {
1866                         /* Cortex-M3/M4 has 4096 bytes autoincrement range */
1867                         armv7m->dap.tar_autoincr_block = (1 << 12);
1868                 }
1869
1870                 /* NOTE: FPB and DWT are both optional. */
1871
1872                 /* Setup FPB */
1873                 target_read_u32(target, FP_CTRL, &fpcr);
1874                 cortex_m3->auto_bp_type = 1;
1875                 cortex_m3->fp_num_code = ((fpcr >> 8) & 0x70) | ((fpcr >> 4) & 0xF);    /* bits
1876                                                                                          *[14:12]
1877                                                                                          *and [7:4]
1878                                                                                          **/
1879                 cortex_m3->fp_num_lit = (fpcr >> 8) & 0xF;
1880                 cortex_m3->fp_code_available = cortex_m3->fp_num_code;
1881                 cortex_m3->fp_comparator_list = calloc(
1882                                 cortex_m3->fp_num_code + cortex_m3->fp_num_lit,
1883                                 sizeof(struct cortex_m3_fp_comparator));
1884                 cortex_m3->fpb_enabled = fpcr & 1;
1885                 for (i = 0; i < cortex_m3->fp_num_code + cortex_m3->fp_num_lit; i++) {
1886                         cortex_m3->fp_comparator_list[i].type =
1887                                 (i < cortex_m3->fp_num_code) ? FPCR_CODE : FPCR_LITERAL;
1888                         cortex_m3->fp_comparator_list[i].fpcr_address = FP_COMP0 + 4 * i;
1889                 }
1890                 LOG_DEBUG("FPB fpcr 0x%" PRIx32 ", numcode %i, numlit %i",
1891                         fpcr,
1892                         cortex_m3->fp_num_code,
1893                         cortex_m3->fp_num_lit);
1894
1895                 /* Setup DWT */
1896                 cortex_m3_dwt_setup(cortex_m3, target);
1897
1898                 /* These hardware breakpoints only work for code in flash! */
1899                 LOG_INFO("%s: hardware has %d breakpoints, %d watchpoints",
1900                         target_name(target),
1901                         cortex_m3->fp_num_code,
1902                         cortex_m3->dwt_num_comp);
1903         }
1904
1905         return ERROR_OK;
1906 }
1907
1908 static int cortex_m3_dcc_read(struct adiv5_dap *swjdp, uint8_t *value, uint8_t *ctrl)
1909 {
1910         uint16_t dcrdr;
1911         int retval;
1912
1913         mem_ap_read_buf_u16(swjdp, (uint8_t *)&dcrdr, 1, DCB_DCRDR);
1914         *ctrl = (uint8_t)dcrdr;
1915         *value = (uint8_t)(dcrdr >> 8);
1916
1917         LOG_DEBUG("data 0x%x ctrl 0x%x", *value, *ctrl);
1918
1919         /* write ack back to software dcc register
1920          * signify we have read data */
1921         if (dcrdr & (1 << 0)) {
1922                 dcrdr = 0;
1923                 retval = mem_ap_write_buf_u16(swjdp, (uint8_t *)&dcrdr, 1, DCB_DCRDR);
1924                 if (retval != ERROR_OK)
1925                         return retval;
1926         }
1927
1928         return ERROR_OK;
1929 }
1930
1931 static int cortex_m3_target_request_data(struct target *target,
1932         uint32_t size, uint8_t *buffer)
1933 {
1934         struct armv7m_common *armv7m = target_to_armv7m(target);
1935         struct adiv5_dap *swjdp = armv7m->arm.dap;
1936         uint8_t data;
1937         uint8_t ctrl;
1938         uint32_t i;
1939
1940         for (i = 0; i < (size * 4); i++) {
1941                 cortex_m3_dcc_read(swjdp, &data, &ctrl);
1942                 buffer[i] = data;
1943         }
1944
1945         return ERROR_OK;
1946 }
1947
1948 static int cortex_m3_handle_target_request(void *priv)
1949 {
1950         struct target *target = priv;
1951         if (!target_was_examined(target))
1952                 return ERROR_OK;
1953         struct armv7m_common *armv7m = target_to_armv7m(target);
1954         struct adiv5_dap *swjdp = armv7m->arm.dap;
1955
1956         if (!target->dbg_msg_enabled)
1957                 return ERROR_OK;
1958
1959         if (target->state == TARGET_RUNNING) {
1960                 uint8_t data;
1961                 uint8_t ctrl;
1962
1963                 cortex_m3_dcc_read(swjdp, &data, &ctrl);
1964
1965                 /* check if we have data */
1966                 if (ctrl & (1 << 0)) {
1967                         uint32_t request;
1968
1969                         /* we assume target is quick enough */
1970                         request = data;
1971                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1972                         request |= (data << 8);
1973                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1974                         request |= (data << 16);
1975                         cortex_m3_dcc_read(swjdp, &data, &ctrl);
1976                         request |= (data << 24);
1977                         target_request(target, request);
1978                 }
1979         }
1980
1981         return ERROR_OK;
1982 }
1983
1984 static int cortex_m3_init_arch_info(struct target *target,
1985         struct cortex_m3_common *cortex_m3, struct jtag_tap *tap)
1986 {
1987         int retval;
1988         struct armv7m_common *armv7m = &cortex_m3->armv7m;
1989
1990         armv7m_init_arch_info(target, armv7m);
1991
1992         /* prepare JTAG information for the new target */
1993         cortex_m3->jtag_info.tap = tap;
1994         cortex_m3->jtag_info.scann_size = 4;
1995
1996         /* default reset mode is to use srst if fitted
1997          * if not it will use CORTEX_M3_RESET_VECTRESET */
1998         cortex_m3->soft_reset_config = CORTEX_M3_RESET_VECTRESET;
1999
2000         armv7m->arm.dap = &armv7m->dap;
2001
2002         /* Leave (only) generic DAP stuff for debugport_init(); */
2003         armv7m->dap.jtag_info = &cortex_m3->jtag_info;
2004         armv7m->dap.memaccess_tck = 8;
2005
2006         /* Cortex-M3/M4 has 4096 bytes autoincrement range
2007          * but set a safe default to 1024 to support Cortex-M0
2008          * this will be changed in cortex_m3_examine if a M3/M4 is detected */
2009         armv7m->dap.tar_autoincr_block = (1 << 10);
2010
2011         /* register arch-specific functions */
2012         armv7m->examine_debug_reason = cortex_m3_examine_debug_reason;
2013
2014         armv7m->post_debug_entry = NULL;
2015
2016         armv7m->pre_restore_context = NULL;
2017
2018         armv7m->load_core_reg_u32 = cortex_m3_load_core_reg_u32;
2019         armv7m->store_core_reg_u32 = cortex_m3_store_core_reg_u32;
2020
2021         target_register_timer_callback(cortex_m3_handle_target_request, 1, 1, target);
2022
2023         retval = arm_jtag_setup_connection(&cortex_m3->jtag_info);
2024         if (retval != ERROR_OK)
2025                 return retval;
2026
2027         return ERROR_OK;
2028 }
2029
2030 static int cortex_m3_target_create(struct target *target, Jim_Interp *interp)
2031 {
2032         struct cortex_m3_common *cortex_m3 = calloc(1, sizeof(struct cortex_m3_common));
2033
2034         cortex_m3->common_magic = CORTEX_M3_COMMON_MAGIC;
2035         cortex_m3_init_arch_info(target, cortex_m3, target->tap);
2036
2037         return ERROR_OK;
2038 }
2039
2040 /*--------------------------------------------------------------------------*/
2041
2042 static int cortex_m3_verify_pointer(struct command_context *cmd_ctx,
2043         struct cortex_m3_common *cm3)
2044 {
2045         if (cm3->common_magic != CORTEX_M3_COMMON_MAGIC) {
2046                 command_print(cmd_ctx, "target is not a Cortex-M3");
2047                 return ERROR_TARGET_INVALID;
2048         }
2049         return ERROR_OK;
2050 }
2051
2052 /*
2053  * Only stuff below this line should need to verify that its target
2054  * is a Cortex-M3.  Everything else should have indirected through the
2055  * cortexm3_target structure, which is only used with CM3 targets.
2056  */
2057
2058 static const struct {
2059         char name[10];
2060         unsigned mask;
2061 } vec_ids[] = {
2062         { "hard_err",   VC_HARDERR, },
2063         { "int_err",    VC_INTERR, },
2064         { "bus_err",    VC_BUSERR, },
2065         { "state_err",  VC_STATERR, },
2066         { "chk_err",    VC_CHKERR, },
2067         { "nocp_err",   VC_NOCPERR, },
2068         { "mm_err",     VC_MMERR, },
2069         { "reset",      VC_CORERESET, },
2070 };
2071
2072 COMMAND_HANDLER(handle_cortex_m3_vector_catch_command)
2073 {
2074         struct target *target = get_current_target(CMD_CTX);
2075         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2076         struct armv7m_common *armv7m = &cortex_m3->armv7m;
2077         struct adiv5_dap *swjdp = armv7m->arm.dap;
2078         uint32_t demcr = 0;
2079         int retval;
2080
2081         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2082         if (retval != ERROR_OK)
2083                 return retval;
2084
2085         retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
2086         if (retval != ERROR_OK)
2087                 return retval;
2088
2089         if (CMD_ARGC > 0) {
2090                 unsigned catch = 0;
2091
2092                 if (CMD_ARGC == 1) {
2093                         if (strcmp(CMD_ARGV[0], "all") == 0) {
2094                                 catch = VC_HARDERR | VC_INTERR | VC_BUSERR
2095                                         | VC_STATERR | VC_CHKERR | VC_NOCPERR
2096                                         | VC_MMERR | VC_CORERESET;
2097                                 goto write;
2098                         } else if (strcmp(CMD_ARGV[0], "none") == 0)
2099                                 goto write;
2100                 }
2101                 while (CMD_ARGC-- > 0) {
2102                         unsigned i;
2103                         for (i = 0; i < ARRAY_SIZE(vec_ids); i++) {
2104                                 if (strcmp(CMD_ARGV[CMD_ARGC], vec_ids[i].name) != 0)
2105                                         continue;
2106                                 catch |= vec_ids[i].mask;
2107                                 break;
2108                         }
2109                         if (i == ARRAY_SIZE(vec_ids)) {
2110                                 LOG_ERROR("No CM3 vector '%s'", CMD_ARGV[CMD_ARGC]);
2111                                 return ERROR_COMMAND_SYNTAX_ERROR;
2112                         }
2113                 }
2114 write:
2115                 /* For now, armv7m->demcr only stores vector catch flags. */
2116                 armv7m->demcr = catch;
2117
2118                 demcr &= ~0xffff;
2119                 demcr |= catch;
2120
2121                 /* write, but don't assume it stuck (why not??) */
2122                 retval = mem_ap_write_u32(swjdp, DCB_DEMCR, demcr);
2123                 if (retval != ERROR_OK)
2124                         return retval;
2125                 retval = mem_ap_read_atomic_u32(swjdp, DCB_DEMCR, &demcr);
2126                 if (retval != ERROR_OK)
2127                         return retval;
2128
2129                 /* FIXME be sure to clear DEMCR on clean server shutdown.
2130                  * Otherwise the vector catch hardware could fire when there's
2131                  * no debugger hooked up, causing much confusion...
2132                  */
2133         }
2134
2135         for (unsigned i = 0; i < ARRAY_SIZE(vec_ids); i++) {
2136                 command_print(CMD_CTX, "%9s: %s", vec_ids[i].name,
2137                         (demcr & vec_ids[i].mask) ? "catch" : "ignore");
2138         }
2139
2140         return ERROR_OK;
2141 }
2142
2143 COMMAND_HANDLER(handle_cortex_m3_mask_interrupts_command)
2144 {
2145         struct target *target = get_current_target(CMD_CTX);
2146         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2147         int retval;
2148
2149         static const Jim_Nvp nvp_maskisr_modes[] = {
2150                 { .name = "auto", .value = CORTEX_M3_ISRMASK_AUTO },
2151                 { .name = "off", .value = CORTEX_M3_ISRMASK_OFF },
2152                 { .name = "on", .value = CORTEX_M3_ISRMASK_ON },
2153                 { .name = NULL, .value = -1 },
2154         };
2155         const Jim_Nvp *n;
2156
2157
2158         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2159         if (retval != ERROR_OK)
2160                 return retval;
2161
2162         if (target->state != TARGET_HALTED) {
2163                 command_print(CMD_CTX, "target must be stopped for \"%s\" command", CMD_NAME);
2164                 return ERROR_OK;
2165         }
2166
2167         if (CMD_ARGC > 0) {
2168                 n = Jim_Nvp_name2value_simple(nvp_maskisr_modes, CMD_ARGV[0]);
2169                 if (n->name == NULL)
2170                         return ERROR_COMMAND_SYNTAX_ERROR;
2171                 cortex_m3->isrmasking_mode = n->value;
2172
2173
2174                 if (cortex_m3->isrmasking_mode == CORTEX_M3_ISRMASK_ON)
2175                         cortex_m3_write_debug_halt_mask(target, C_HALT | C_MASKINTS, 0);
2176                 else
2177                         cortex_m3_write_debug_halt_mask(target, C_HALT, C_MASKINTS);
2178         }
2179
2180         n = Jim_Nvp_value2name_simple(nvp_maskisr_modes, cortex_m3->isrmasking_mode);
2181         command_print(CMD_CTX, "cortex_m3 interrupt mask %s", n->name);
2182
2183         return ERROR_OK;
2184 }
2185
2186 COMMAND_HANDLER(handle_cortex_m3_reset_config_command)
2187 {
2188         struct target *target = get_current_target(CMD_CTX);
2189         struct cortex_m3_common *cortex_m3 = target_to_cm3(target);
2190         int retval;
2191         char *reset_config;
2192
2193         retval = cortex_m3_verify_pointer(CMD_CTX, cortex_m3);
2194         if (retval != ERROR_OK)
2195                 return retval;
2196
2197         if (CMD_ARGC > 0) {
2198                 if (strcmp(*CMD_ARGV, "sysresetreq") == 0)
2199                         cortex_m3->soft_reset_config = CORTEX_M3_RESET_SYSRESETREQ;
2200                 else if (strcmp(*CMD_ARGV, "vectreset") == 0)
2201                         cortex_m3->soft_reset_config = CORTEX_M3_RESET_VECTRESET;
2202         }
2203
2204         switch (cortex_m3->soft_reset_config) {
2205                 case CORTEX_M3_RESET_SYSRESETREQ:
2206                         reset_config = "sysresetreq";
2207                         break;
2208
2209                 case CORTEX_M3_RESET_VECTRESET:
2210                         reset_config = "vectreset";
2211                         break;
2212
2213                 default:
2214                         reset_config = "unknown";
2215                         break;
2216         }
2217
2218         command_print(CMD_CTX, "cortex_m3 reset_config %s", reset_config);
2219
2220         return ERROR_OK;
2221 }
2222
2223 static const struct command_registration cortex_m3_exec_command_handlers[] = {
2224         {
2225                 .name = "maskisr",
2226                 .handler = handle_cortex_m3_mask_interrupts_command,
2227                 .mode = COMMAND_EXEC,
2228                 .help = "mask cortex_m3 interrupts",
2229                 .usage = "['auto'|'on'|'off']",
2230         },
2231         {
2232                 .name = "vector_catch",
2233                 .handler = handle_cortex_m3_vector_catch_command,
2234                 .mode = COMMAND_EXEC,
2235                 .help = "configure hardware vectors to trigger debug entry",
2236                 .usage = "['all'|'none'|('bus_err'|'chk_err'|...)*]",
2237         },
2238         {
2239                 .name = "reset_config",
2240                 .handler = handle_cortex_m3_reset_config_command,
2241                 .mode = COMMAND_ANY,
2242                 .help = "configure software reset handling",
2243                 .usage = "['srst'|'sysresetreq'|'vectreset']",
2244         },
2245         COMMAND_REGISTRATION_DONE
2246 };
2247 static const struct command_registration cortex_m3_command_handlers[] = {
2248         {
2249                 .chain = armv7m_command_handlers,
2250         },
2251         {
2252                 .name = "cortex_m3",
2253                 .mode = COMMAND_EXEC,
2254                 .help = "Cortex-M3 command group",
2255                 .usage = "",
2256                 .chain = cortex_m3_exec_command_handlers,
2257         },
2258         COMMAND_REGISTRATION_DONE
2259 };
2260
2261 struct target_type cortexm3_target = {
2262         .name = "cortex_m3",
2263
2264         .poll = cortex_m3_poll,
2265         .arch_state = armv7m_arch_state,
2266
2267         .target_request_data = cortex_m3_target_request_data,
2268
2269         .halt = cortex_m3_halt,
2270         .resume = cortex_m3_resume,
2271         .step = cortex_m3_step,
2272
2273         .assert_reset = cortex_m3_assert_reset,
2274         .deassert_reset = cortex_m3_deassert_reset,
2275         .soft_reset_halt = cortex_m3_soft_reset_halt,
2276
2277         .get_gdb_reg_list = armv7m_get_gdb_reg_list,
2278
2279         .read_memory = cortex_m3_read_memory,
2280         .write_memory = cortex_m3_write_memory,
2281         .bulk_write_memory = cortex_m3_bulk_write_memory,
2282         .checksum_memory = armv7m_checksum_memory,
2283         .blank_check_memory = armv7m_blank_check_memory,
2284
2285         .run_algorithm = armv7m_run_algorithm,
2286         .start_algorithm = armv7m_start_algorithm,
2287         .wait_algorithm = armv7m_wait_algorithm,
2288
2289         .add_breakpoint = cortex_m3_add_breakpoint,
2290         .remove_breakpoint = cortex_m3_remove_breakpoint,
2291         .add_watchpoint = cortex_m3_add_watchpoint,
2292         .remove_watchpoint = cortex_m3_remove_watchpoint,
2293
2294         .commands = cortex_m3_command_handlers,
2295         .target_create = cortex_m3_target_create,
2296         .init_target = cortex_m3_init_target,
2297         .examine = cortex_m3_examine,
2298 };