openocd: src/target: replace the GPL-2.0-or-later license tag
[fw/openocd] / src / target / arm7tdmi.c
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2
3 /***************************************************************************
4  *   Copyright (C) 2005 by Dominic Rath                                    *
5  *   Dominic.Rath@gmx.de                                                   *
6  *                                                                         *
7  *   Copyright (C) 2008 by Spencer Oliver                                  *
8  *   spen@spen-soft.co.uk                                                  *
9  *                                                                         *
10  *   Copyright (C) 2007,2008 Ã˜yvind Harboe                                 *
11  *   oyvind.harboe@zylin.com                                               *
12  ***************************************************************************/
13
14 #ifdef HAVE_CONFIG_H
15 #include "config.h"
16 #endif
17
18 #include "arm7tdmi.h"
19 #include "target_type.h"
20 #include "register.h"
21 #include "arm_opcodes.h"
22 #include "arm_semihosting.h"
23
24 /*
25  * For information about ARM7TDMI, see ARM DDI 0210C (r4p1)
26  * or ARM DDI 0029G (r3).  "Debug In Depth", Appendix B,
27  * covers JTAG support.
28  */
29
30 #if 0
31 #define _DEBUG_INSTRUCTION_EXECUTION_
32 #endif
33
34 static int arm7tdmi_examine_debug_reason(struct target *target)
35 {
36         int retval = ERROR_OK;
37         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
38
39         /* only check the debug reason if we don't know it already */
40         if ((target->debug_reason != DBG_REASON_DBGRQ)
41                         && (target->debug_reason != DBG_REASON_SINGLESTEP)) {
42                 struct scan_field fields[2];
43                 uint8_t databus[4];
44                 uint8_t breakpoint;
45
46                 fields[0].num_bits = 1;
47                 fields[0].out_value = NULL;
48                 fields[0].in_value = &breakpoint;
49
50                 fields[1].num_bits = 32;
51                 fields[1].out_value = NULL;
52                 fields[1].in_value = databus;
53
54                 retval = arm_jtag_scann(&arm7_9->jtag_info, 0x1, TAP_DRPAUSE);
55                 if (retval != ERROR_OK)
56                         return retval;
57                 retval = arm_jtag_set_instr(arm7_9->jtag_info.tap, arm7_9->jtag_info.intest_instr, NULL, TAP_DRPAUSE);
58                 if (retval != ERROR_OK)
59                         return retval;
60
61                 jtag_add_dr_scan(arm7_9->jtag_info.tap, 2, fields, TAP_DRPAUSE);
62                 retval = jtag_execute_queue();
63                 if (retval != ERROR_OK)
64                         return retval;
65
66                 fields[0].in_value = NULL;
67                 fields[0].out_value = &breakpoint;
68                 fields[1].in_value = NULL;
69                 fields[1].out_value = databus;
70
71                 jtag_add_dr_scan(arm7_9->jtag_info.tap, 2, fields, TAP_DRPAUSE);
72
73                 if (breakpoint & 1)
74                         target->debug_reason = DBG_REASON_WATCHPOINT;
75                 else
76                         target->debug_reason = DBG_REASON_BREAKPOINT;
77         }
78
79         return ERROR_OK;
80 }
81
82 static const int arm7tdmi_num_bits[] = {1, 32};
83
84 static inline int arm7tdmi_clock_out_inner(struct arm_jtag *jtag_info, uint32_t out, int breakpoint)
85 {
86         uint8_t bp = breakpoint ? 1 : 0;
87         uint8_t out_value[4];
88         buf_set_u32(out_value, 0, 32, flip_u32(out, 32));
89
90         struct scan_field fields[2] = {
91                         { .num_bits = arm7tdmi_num_bits[0], .out_value = &bp },
92                         { .num_bits = arm7tdmi_num_bits[1], .out_value = out_value },
93         };
94
95         jtag_add_dr_scan(jtag_info->tap,
96                         2,
97                         fields,
98                         TAP_DRPAUSE);
99
100         jtag_add_runtest(0, TAP_DRPAUSE);
101
102         return ERROR_OK;
103 }
104
105 /* put an instruction in the ARM7TDMI pipeline or write the data bus,
106  * and optionally read data
107  */
108 static inline int arm7tdmi_clock_out(struct arm_jtag *jtag_info,
109                 uint32_t out, int breakpoint)
110 {
111         int retval;
112         retval = arm_jtag_scann(jtag_info, 0x1, TAP_DRPAUSE);
113         if (retval != ERROR_OK)
114                 return retval;
115         retval = arm_jtag_set_instr(jtag_info->tap, jtag_info->intest_instr, NULL, TAP_DRPAUSE);
116         if (retval != ERROR_OK)
117                 return retval;
118
119         return arm7tdmi_clock_out_inner(jtag_info, out, breakpoint);
120 }
121
122 /* clock the target, reading the databus */
123 static int arm7tdmi_clock_data_in(struct arm_jtag *jtag_info, uint32_t *in)
124 {
125         int retval = ERROR_OK;
126         struct scan_field fields[2];
127
128         retval = arm_jtag_scann(jtag_info, 0x1, TAP_DRPAUSE);
129         if (retval != ERROR_OK)
130                 return retval;
131         retval = arm_jtag_set_instr(jtag_info->tap, jtag_info->intest_instr, NULL, TAP_DRPAUSE);
132         if (retval != ERROR_OK)
133                 return retval;
134
135         fields[0].num_bits = 1;
136         fields[0].out_value = NULL;
137         fields[0].in_value = NULL;
138
139         fields[1].num_bits = 32;
140         fields[1].out_value = NULL;
141         fields[1].in_value = (uint8_t *)in;
142
143         jtag_add_dr_scan(jtag_info->tap, 2, fields, TAP_DRPAUSE);
144
145         jtag_add_callback(arm7flip32, (jtag_callback_data_t)in);
146
147         jtag_add_runtest(0, TAP_DRPAUSE);
148
149 #ifdef _DEBUG_INSTRUCTION_EXECUTION_
150         retval = jtag_execute_queue();
151         if (retval != ERROR_OK)
152                 return retval;
153
154         if (in)
155                 LOG_DEBUG("in: 0x%8.8x", *in);
156         else
157                 LOG_ERROR("BUG: called with in == NULL");
158 #endif
159
160         return ERROR_OK;
161 }
162
163 /* clock the target, and read the databus
164  * the *in pointer points to a buffer where elements of 'size' bytes
165  * are stored in big (be == 1) or little (be == 0) endianness
166  */
167 static int arm7tdmi_clock_data_in_endianness(struct arm_jtag *jtag_info,
168                 void *in, int size, int be)
169 {
170         int retval = ERROR_OK;
171         struct scan_field fields[3];
172
173         retval = arm_jtag_scann(jtag_info, 0x1, TAP_DRPAUSE);
174         if (retval != ERROR_OK)
175                 return retval;
176         retval = arm_jtag_set_instr(jtag_info->tap, jtag_info->intest_instr, NULL, TAP_DRPAUSE);
177         if (retval != ERROR_OK)
178                 return retval;
179
180         fields[0].num_bits = 1;
181         fields[0].out_value = NULL;
182         fields[0].in_value = NULL;
183
184         if (size == 4) {
185                 fields[1].num_bits = 32;
186                 fields[1].out_value = NULL;
187                 fields[1].in_value = in;
188         } else {
189                 /* Discard irrelevant bits of the scan, making sure we don't write more
190                  * than size bytes to in */
191                 fields[1].num_bits = 32 - size * 8;
192                 fields[1].out_value = NULL;
193                 fields[1].in_value = NULL;
194
195                 fields[2].num_bits = size * 8;
196                 fields[2].out_value = NULL;
197                 fields[2].in_value = in;
198         }
199
200         jtag_add_dr_scan(jtag_info->tap, size == 4 ? 2 : 3, fields, TAP_DRPAUSE);
201
202         jtag_add_callback4(arm7_9_endianness_callback,
203                 (jtag_callback_data_t)in,
204                 (jtag_callback_data_t)size,
205                 (jtag_callback_data_t)be,
206                 (jtag_callback_data_t)1);
207
208         jtag_add_runtest(0, TAP_DRPAUSE);
209
210 #ifdef _DEBUG_INSTRUCTION_EXECUTION_
211 {
212                 retval = jtag_execute_queue();
213                 if (retval != ERROR_OK)
214                         return retval;
215
216                 if (in)
217                         LOG_DEBUG("in: 0x%8.8x", *(uint32_t *)in);
218                 else
219                         LOG_ERROR("BUG: called with in == NULL");
220 }
221 #endif
222
223         return ERROR_OK;
224 }
225
226 static void arm7tdmi_change_to_arm(struct target *target,
227                 uint32_t *r0, uint32_t *pc)
228 {
229         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
230         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
231
232         /* save r0 before using it and put system in ARM state
233          * to allow common handling of ARM and THUMB debugging */
234
235         /* fetch STR r0, [r0] */
236         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_STR(0, 0), 0);
237         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
238         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
239         /* nothing fetched, STR r0, [r0] in Execute (2) */
240         arm7tdmi_clock_data_in(jtag_info, r0);
241
242         /* MOV r0, r15 fetched, STR in Decode */
243         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_MOV(0, 15), 0);
244         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_STR(0, 0), 0);
245         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
246         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
247         /* nothing fetched, STR r0, [r0] in Execute (2) */
248         arm7tdmi_clock_data_in(jtag_info, pc);
249
250         /* use pc-relative LDR to clear r0[1:0] (for switch to ARM mode) */
251         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_LDR_PCREL(0), 0);
252         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
253         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
254         /* nothing fetched, data for LDR r0, [PC, #0] */
255         arm7tdmi_clock_out(jtag_info, 0x0, 0);
256         /* nothing fetched, data from previous cycle is written to register */
257         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
258
259         /* fetch BX */
260         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_BX(0), 0);
261         /* NOP fetched, BX in Decode, MOV in Execute */
262         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
263         /* NOP fetched, BX in Execute (1) */
264         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
265
266         jtag_execute_queue();
267
268         /* fix program counter:
269          * MOV r0, r15 was the 4th instruction (+6)
270          * reading PC in Thumb state gives address of instruction + 4
271          */
272         *pc -= 0xa;
273 }
274
275 /* FIX!!! is this a potential performance bottleneck w.r.t. requiring too many
276  * roundtrips when jtag_execute_queue() has a large overhead(e.g. for USB)s?
277  *
278  * The solution is to arrange for a large out/in scan in this loop and
279  * and convert data afterwards.
280  */
281 static void arm7tdmi_read_core_regs(struct target *target,
282                 uint32_t mask, uint32_t *core_regs[16])
283 {
284         int i;
285         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
286         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
287
288         /* STMIA r0-15, [r0] at debug speed
289          * register values will start to appear on 4th DCLK
290          */
291         arm7tdmi_clock_out(jtag_info, ARMV4_5_STMIA(0, mask & 0xffff, 0, 0), 0);
292
293         /* fetch NOP, STM in DECODE stage */
294         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
295         /* fetch NOP, STM in EXECUTE stage (1st cycle) */
296         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
297
298         for (i = 0; i <= 15; i++) {
299                 if (mask & (1 << i))
300                         /* nothing fetched, STM still in EXECUTE (1 + i cycle) */
301                         arm7tdmi_clock_data_in(jtag_info, core_regs[i]);
302         }
303 }
304
305 static void arm7tdmi_read_core_regs_target_buffer(struct target *target,
306                 uint32_t mask, void *buffer, int size)
307 {
308         int i;
309         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
310         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
311         int be = (target->endianness == TARGET_BIG_ENDIAN) ? 1 : 0;
312         uint32_t *buf_u32 = buffer;
313         uint16_t *buf_u16 = buffer;
314         uint8_t *buf_u8 = buffer;
315
316         /* STMIA r0-15, [r0] at debug speed
317          * register values will start to appear on 4th DCLK
318          */
319         arm7tdmi_clock_out(jtag_info, ARMV4_5_STMIA(0, mask & 0xffff, 0, 0), 0);
320
321         /* fetch NOP, STM in DECODE stage */
322         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
323         /* fetch NOP, STM in EXECUTE stage (1st cycle) */
324         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
325
326         for (i = 0; i <= 15; i++) {
327                 /* nothing fetched, STM still in EXECUTE (1 + i cycle), read databus */
328                 if (mask & (1 << i)) {
329                         switch (size) {
330                                 case 4:
331                                         arm7tdmi_clock_data_in_endianness(jtag_info, buf_u32++, 4, be);
332                                         break;
333                                 case 2:
334                                         arm7tdmi_clock_data_in_endianness(jtag_info, buf_u16++, 2, be);
335                                         break;
336                                 case 1:
337                                         arm7tdmi_clock_data_in_endianness(jtag_info, buf_u8++, 1, be);
338                                         break;
339                         }
340                 }
341         }
342 }
343
344 static void arm7tdmi_read_xpsr(struct target *target, uint32_t *xpsr, int spsr)
345 {
346         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
347         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
348
349         /* MRS r0, cpsr */
350         arm7tdmi_clock_out(jtag_info, ARMV4_5_MRS(0, spsr & 1), 0);
351
352         /* STR r0, [r15] */
353         arm7tdmi_clock_out(jtag_info, ARMV4_5_STR(0, 15), 0);
354         /* fetch NOP, STR in DECODE stage */
355         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
356         /* fetch NOP, STR in EXECUTE stage (1st cycle) */
357         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
358         /* nothing fetched, STR still in EXECUTE (2nd cycle) */
359         arm7tdmi_clock_data_in(jtag_info, xpsr);
360 }
361
362 static void arm7tdmi_write_xpsr(struct target *target, uint32_t xpsr, int spsr)
363 {
364         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
365         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
366
367         LOG_DEBUG("xpsr: %8.8" PRIx32 ", spsr: %i", xpsr, spsr);
368
369         /* MSR1 fetched */
370         arm7tdmi_clock_out(jtag_info, ARMV4_5_MSR_IM(xpsr & 0xff, 0, 1, spsr), 0);
371         /* MSR2 fetched, MSR1 in DECODE */
372         arm7tdmi_clock_out(jtag_info, ARMV4_5_MSR_IM((xpsr & 0xff00) >> 8, 0xc, 2, spsr), 0);
373         /* MSR3 fetched, MSR1 in EXECUTE (1), MSR2 in DECODE */
374         arm7tdmi_clock_out(jtag_info, ARMV4_5_MSR_IM((xpsr & 0xff0000) >> 16, 0x8, 4, spsr), 0);
375         /* nothing fetched, MSR1 in EXECUTE (2) */
376         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
377         /* MSR4 fetched, MSR2 in EXECUTE (1), MSR3 in DECODE */
378         arm7tdmi_clock_out(jtag_info, ARMV4_5_MSR_IM((xpsr & 0xff000000) >> 24, 0x4, 8, spsr), 0);
379         /* nothing fetched, MSR2 in EXECUTE (2) */
380         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
381         /* NOP fetched, MSR3 in EXECUTE (1), MSR4 in DECODE */
382         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
383         /* nothing fetched, MSR3 in EXECUTE (2) */
384         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
385         /* NOP fetched, MSR4 in EXECUTE (1) */
386         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
387         /* nothing fetched, MSR4 in EXECUTE (2) */
388         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
389 }
390
391 static void arm7tdmi_write_xpsr_im8(struct target *target,
392                 uint8_t xpsr_im, int rot, int spsr)
393 {
394         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
395         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
396
397         LOG_DEBUG("xpsr_im: %2.2x, rot: %i, spsr: %i", xpsr_im, rot, spsr);
398
399         /* MSR fetched */
400         arm7tdmi_clock_out(jtag_info, ARMV4_5_MSR_IM(xpsr_im, rot, 1, spsr), 0);
401         /* NOP fetched, MSR in DECODE */
402         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
403         /* NOP fetched, MSR in EXECUTE (1) */
404         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
405         /* nothing fetched, MSR in EXECUTE (2) */
406         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
407 }
408
409 static void arm7tdmi_write_core_regs(struct target *target,
410                 uint32_t mask, uint32_t core_regs[16])
411 {
412         int i;
413         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
414         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
415
416         /* LDMIA r0-15, [r0] at debug speed
417         * register values will start to appear on 4th DCLK
418         */
419         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDMIA(0, mask & 0xffff, 0, 0), 0);
420
421         /* fetch NOP, LDM in DECODE stage */
422         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
423         /* fetch NOP, LDM in EXECUTE stage (1st cycle) */
424         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
425
426         for (i = 0; i <= 15; i++) {
427                 if (mask & (1 << i))
428                         /* nothing fetched, LDM still in EXECUTE (1 + i cycle) */
429                         arm7tdmi_clock_out_inner(jtag_info, core_regs[i], 0);
430         }
431         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
432 }
433
434 static void arm7tdmi_load_word_regs(struct target *target, uint32_t mask)
435 {
436         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
437         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
438
439         /* put system-speed load-multiple into the pipeline */
440         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
441         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
442         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDMIA(0, mask & 0xffff, 0, 1), 0);
443 }
444
445 static void arm7tdmi_load_hword_reg(struct target *target, int num)
446 {
447         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
448         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
449
450         /* put system-speed load half-word into the pipeline */
451         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
452         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
453         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDRH_IP(num, 0), 0);
454 }
455
456 static void arm7tdmi_load_byte_reg(struct target *target, int num)
457 {
458         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
459         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
460
461         /* put system-speed load byte into the pipeline */
462         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
463         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
464         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDRB_IP(num, 0), 0);
465 }
466
467 static void arm7tdmi_store_word_regs(struct target *target, uint32_t mask)
468 {
469         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
470         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
471
472         /* put system-speed store-multiple into the pipeline */
473         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
474         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
475         arm7tdmi_clock_out(jtag_info, ARMV4_5_STMIA(0, mask, 0, 1), 0);
476 }
477
478 static void arm7tdmi_store_hword_reg(struct target *target, int num)
479 {
480         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
481         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
482
483         /* put system-speed store half-word into the pipeline */
484         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
485         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
486         arm7tdmi_clock_out(jtag_info, ARMV4_5_STRH_IP(num, 0), 0);
487 }
488
489 static void arm7tdmi_store_byte_reg(struct target *target, int num)
490 {
491         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
492         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
493
494         /* put system-speed store byte into the pipeline */
495         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
496         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
497         arm7tdmi_clock_out(jtag_info, ARMV4_5_STRB_IP(num, 0), 0);
498 }
499
500 static void arm7tdmi_write_pc(struct target *target, uint32_t pc)
501 {
502         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
503         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
504
505         /* LDMIA r0-15, [r0] at debug speed
506          * register values will start to appear on 4th DCLK
507          */
508         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDMIA(0, 0x8000, 0, 0), 0);
509         /* fetch NOP, LDM in DECODE stage */
510         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
511         /* fetch NOP, LDM in EXECUTE stage (1st cycle) */
512         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
513         /* nothing fetched, LDM in EXECUTE stage (1st cycle) load register */
514         arm7tdmi_clock_out_inner(jtag_info, pc, 0);
515         /* nothing fetched, LDM in EXECUTE stage (2nd cycle) load register */
516         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
517         /* nothing fetched, LDM in EXECUTE stage (3rd cycle) load register */
518         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
519         /* fetch NOP, LDM in EXECUTE stage (4th cycle) */
520         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
521         /* fetch NOP, LDM in EXECUTE stage (5th cycle) */
522         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_NOP, 0);
523 }
524
525 static void arm7tdmi_branch_resume(struct target *target)
526 {
527         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
528         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
529
530         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 1);
531         arm7tdmi_clock_out_inner(jtag_info, ARMV4_5_B(0xfffffa, 0), 0);
532 }
533
534 static void arm7tdmi_branch_resume_thumb(struct target *target)
535 {
536         struct arm7_9_common *arm7_9 = target_to_arm7_9(target);
537         struct arm *arm = &arm7_9->arm;
538         struct arm_jtag *jtag_info = &arm7_9->jtag_info;
539         struct reg *dbg_stat = &arm7_9->eice_cache->reg_list[EICE_DBG_STAT];
540
541         LOG_DEBUG("-");
542
543         /* LDMIA r0, [r0] at debug speed
544          * register values will start to appear on 4th DCLK
545          */
546         arm7tdmi_clock_out(jtag_info, ARMV4_5_LDMIA(0, 0x1, 0, 0), 0);
547
548         /* fetch NOP, LDM in DECODE stage */
549         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
550         /* fetch NOP, LDM in EXECUTE stage (1st cycle) */
551         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
552         /* nothing fetched, LDM in EXECUTE stage (2nd cycle) */
553         arm7tdmi_clock_out(jtag_info, buf_get_u32(arm->pc->value, 0, 32) | 1, 0);
554         /* nothing fetched, LDM in EXECUTE stage (3rd cycle) */
555         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
556
557         /* Branch and eXchange */
558         arm7tdmi_clock_out(jtag_info, ARMV4_5_BX(0), 0);
559
560         embeddedice_read_reg(dbg_stat);
561
562         /* fetch NOP, BX in DECODE stage */
563         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
564
565         /* target is now in Thumb state */
566         embeddedice_read_reg(dbg_stat);
567
568         /* fetch NOP, BX in EXECUTE stage (1st cycle) */
569         arm7tdmi_clock_out(jtag_info, ARMV4_5_NOP, 0);
570
571         /* target is now in Thumb state */
572         embeddedice_read_reg(dbg_stat);
573
574         /* load r0 value */
575         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_LDR_PCREL(0), 0);
576         /* fetch NOP, LDR in Decode */
577         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
578         /* fetch NOP, LDR in Execute */
579         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
580         /* nothing fetched, LDR in EXECUTE stage (2nd cycle) */
581         arm7tdmi_clock_out(jtag_info, buf_get_u32(arm->core_cache->reg_list[0].value, 0, 32), 0);
582         /* nothing fetched, LDR in EXECUTE stage (3rd cycle) */
583         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
584
585         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
586         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 0);
587
588         embeddedice_read_reg(dbg_stat);
589
590         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_NOP, 1);
591         arm7tdmi_clock_out(jtag_info, ARMV4_5_T_B(0x7f8), 0);
592 }
593
594 static void arm7tdmi_build_reg_cache(struct target *target)
595 {
596         struct reg_cache **cache_p = register_get_last_cache_p(&target->reg_cache);
597         struct arm *arm = target_to_arm(target);
598
599         (*cache_p) = arm_build_reg_cache(target, arm);
600 }
601
602 static void arm7tdmi_free_reg_cache(struct target *target)
603 {
604         struct arm *arm = target_to_arm(target);
605
606         arm_free_reg_cache(arm);
607 }
608
609 int arm7tdmi_init_target(struct command_context *cmd_ctx, struct target *target)
610 {
611         arm7tdmi_build_reg_cache(target);
612         arm_semihosting_init(target);
613         return ERROR_OK;
614 }
615
616 void arm7tdmi_deinit_target(struct target *target)
617 {
618         arm7tdmi_free_reg_cache(target);
619 }
620
621 int arm7tdmi_init_arch_info(struct target *target,
622                 struct arm7_9_common *arm7_9, struct jtag_tap *tap)
623 {
624         /* prepare JTAG information for the new target */
625         arm7_9->jtag_info.tap = tap;
626         arm7_9->jtag_info.scann_size = 4;
627
628         /* register arch-specific functions */
629         arm7_9->examine_debug_reason = arm7tdmi_examine_debug_reason;
630         arm7_9->change_to_arm = arm7tdmi_change_to_arm;
631         arm7_9->read_core_regs = arm7tdmi_read_core_regs;
632         arm7_9->read_core_regs_target_buffer = arm7tdmi_read_core_regs_target_buffer;
633         arm7_9->read_xpsr = arm7tdmi_read_xpsr;
634
635         arm7_9->write_xpsr = arm7tdmi_write_xpsr;
636         arm7_9->write_xpsr_im8 = arm7tdmi_write_xpsr_im8;
637         arm7_9->write_core_regs = arm7tdmi_write_core_regs;
638
639         arm7_9->load_word_regs = arm7tdmi_load_word_regs;
640         arm7_9->load_hword_reg = arm7tdmi_load_hword_reg;
641         arm7_9->load_byte_reg = arm7tdmi_load_byte_reg;
642
643         arm7_9->store_word_regs = arm7tdmi_store_word_regs;
644         arm7_9->store_hword_reg = arm7tdmi_store_hword_reg;
645         arm7_9->store_byte_reg = arm7tdmi_store_byte_reg;
646
647         arm7_9->write_pc = arm7tdmi_write_pc;
648         arm7_9->branch_resume = arm7tdmi_branch_resume;
649         arm7_9->branch_resume_thumb = arm7tdmi_branch_resume_thumb;
650
651         arm7_9->enable_single_step = arm7_9_enable_eice_step;
652         arm7_9->disable_single_step = arm7_9_disable_eice_step;
653
654         arm7_9->write_memory = arm7_9_write_memory;
655         arm7_9->bulk_write_memory = arm7_9_bulk_write_memory;
656
657         arm7_9->post_debug_entry = NULL;
658
659         arm7_9->pre_restore_context = NULL;
660
661         /* initialize arch-specific breakpoint handling */
662         arm7_9->arm_bkpt = 0xdeeedeee;
663         arm7_9->thumb_bkpt = 0xdeee;
664
665         arm7_9->dbgreq_adjust_pc = 2;
666
667         arm7_9_init_arch_info(target, arm7_9);
668
669         return ERROR_OK;
670 }
671
672 static int arm7tdmi_target_create(struct target *target, Jim_Interp *interp)
673 {
674         struct arm7_9_common *arm7_9;
675
676         arm7_9 = calloc(1, sizeof(struct arm7_9_common));
677         arm7tdmi_init_arch_info(target, arm7_9, target->tap);
678         arm7_9->arm.arch = ARM_ARCH_V4;
679
680         return ERROR_OK;
681 }
682
683 /** Holds methods for ARM7TDMI targets. */
684 struct target_type arm7tdmi_target = {
685         .name = "arm7tdmi",
686
687         .poll = arm7_9_poll,
688         .arch_state = arm_arch_state,
689
690         .target_request_data = arm7_9_target_request_data,
691
692         .halt = arm7_9_halt,
693         .resume = arm7_9_resume,
694         .step = arm7_9_step,
695
696         .assert_reset = arm7_9_assert_reset,
697         .deassert_reset = arm7_9_deassert_reset,
698         .soft_reset_halt = arm7_9_soft_reset_halt,
699
700         .get_gdb_arch = arm_get_gdb_arch,
701         .get_gdb_reg_list = arm_get_gdb_reg_list,
702
703         .read_memory = arm7_9_read_memory,
704         .write_memory = arm7_9_write_memory_opt,
705
706         .checksum_memory = arm_checksum_memory,
707         .blank_check_memory = arm_blank_check_memory,
708
709         .run_algorithm = armv4_5_run_algorithm,
710
711         .add_breakpoint = arm7_9_add_breakpoint,
712         .remove_breakpoint = arm7_9_remove_breakpoint,
713         .add_watchpoint = arm7_9_add_watchpoint,
714         .remove_watchpoint = arm7_9_remove_watchpoint,
715
716         .commands  = arm7_9_command_handlers,
717         .target_create  = arm7tdmi_target_create,
718         .init_target = arm7tdmi_init_target,
719         .deinit_target = arm7tdmi_deinit_target,
720         .examine = arm7_9_examine,
721         .check_reset = arm7_9_check_reset,
722 };