1ec73b2d24be103df3ac4e7907dc01d839074b59
[fw/openocd] / src / jtag / jlink.c
1 /***************************************************************************
2  *   Copyright (C) 2007 by Juergen Stuber <juergen@jstuber.net>            *
3  *   based on Dominic Rath's and Benedikt Sauter's usbprog.c               *
4  *                                                                         *
5  *   Copyright (C) 2008 by Spencer Oliver                                  *
6  *   spen@spen-soft.co.uk                                                  *
7  *                                                                         *
8  *   This program is free software; you can redistribute it and/or modify  *
9  *   it under the terms of the GNU General Public License as published by  *
10  *   the Free Software Foundation; either version 2 of the License, or     *
11  *   (at your option) any later version.                                   *
12  *                                                                         *
13  *   This program is distributed in the hope that it will be useful,       *
14  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
15  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
16  *   GNU General Public License for more details.                          *
17  *                                                                         *
18  *   You should have received a copy of the GNU General Public License     *
19  *   along with this program; if not, write to the                         *
20  *   Free Software Foundation, Inc.,                                       *
21  *   59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.             *
22  ***************************************************************************/
23
24 #ifdef HAVE_CONFIG_H
25 #include "config.h"
26 #endif
27
28 #include "interface.h"
29 #include "commands.h"
30
31 #include <usb.h>
32
33
34 #define VID 0x1366
35 #define PID 0x0101
36
37 #define JLINK_WRITE_ENDPOINT    0x02
38 #define JLINK_READ_ENDPOINT             0x81
39
40 static unsigned int jlink_write_ep = JLINK_WRITE_ENDPOINT;
41 static unsigned int jlink_read_ep = JLINK_READ_ENDPOINT;
42 static unsigned int jlink_hw_jtag_version = 2;
43
44 #define JLINK_USB_TIMEOUT               1000
45
46 // See Section 1.3.2 of the Segger JLink USB protocol manual
47 /* 2048 is the max value we can use here */
48 //#define JLINK_TAP_BUFFER_SIZE 2048
49 #define JLINK_TAP_BUFFER_SIZE 256
50 //#define JLINK_TAP_BUFFER_SIZE 384
51
52 #define JLINK_IN_BUFFER_SIZE                    2048
53 #define JLINK_OUT_BUFFER_SIZE                   2*2048 + 4
54 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
55
56 /* Global USB buffers */
57 static uint8_t usb_in_buffer[JLINK_IN_BUFFER_SIZE];
58 static uint8_t usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
59 static uint8_t usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
60
61 /* Constants for JLink command */
62 #define EMU_CMD_VERSION         0x01
63 #define EMU_CMD_SET_SPEED               0x05
64 #define EMU_CMD_GET_STATE               0x07
65 #define EMU_CMD_HW_CLOCK                        0xc8
66 #define EMU_CMD_HW_TMS0                 0xc9
67 #define EMU_CMD_HW_TMS1                 0xca
68 #define EMU_CMD_HW_JTAG2                0xce
69 #define EMU_CMD_HW_JTAG3                0xcf
70 #define EMU_CMD_GET_MAX_MEM_BLOCK       0xd4
71 #define EMU_CMD_HW_RESET0               0xdc
72 #define EMU_CMD_HW_RESET1               0xdd
73 #define EMU_CMD_HW_TRST0                0xde
74 #define EMU_CMD_HW_TRST1                0xdf
75 #define EMU_CMD_GET_CAPS                0xe8
76 #define EMU_CMD_GET_HW_VERSION  0xf0
77
78 /* bits return from EMU_CMD_GET_CAPS */
79 #define EMU_CAP_GET_HW_VERSION          1
80 #define EMU_CAP_GET_MAX_BLOCK_SIZE      11
81
82 /* max speed 12MHz v5.0 jlink */
83 #define JLINK_MAX_SPEED 12000
84
85 /* External interface functions */
86 static int jlink_execute_queue(void);
87 static int jlink_speed(int speed);
88 static int jlink_speed_div(int speed, int* khz);
89 static int jlink_khz(int khz, int *jtag_speed);
90 static int jlink_register_commands(struct command_context_s *cmd_ctx);
91 static int jlink_init(void);
92 static int jlink_quit(void);
93
94 /* CLI command handler functions */
95 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
96 static int jlink_handle_jlink_hw_jtag_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc);
97
98 /* Queue command functions */
99 static void jlink_end_state(tap_state_t state);
100 static void jlink_state_move(void);
101 static void jlink_path_move(int num_states, tap_state_t *path);
102 static void jlink_runtest(int num_cycles);
103 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, scan_command_t *command);
104 static void jlink_reset(int trst, int srst);
105 static void jlink_simple_command(uint8_t command);
106 static int jlink_get_status(void);
107
108 /* J-Link tap buffer functions */
109 static void jlink_tap_init(void);
110 static int jlink_tap_execute(void);
111 static void jlink_tap_ensure_space(int scans, int bits);
112 static void jlink_tap_append_step(int tms, int tdi);
113 static void jlink_tap_append_scan(int length, uint8_t *buffer, scan_command_t *command);
114
115 /* Jlink lowlevel functions */
116 typedef struct jlink_jtag
117 {
118         struct usb_dev_handle* usb_handle;
119 } jlink_jtag_t;
120
121 static jlink_jtag_t *jlink_usb_open(void);
122 static void jlink_usb_close(jlink_jtag_t *jlink_jtag);
123 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length);
124 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length);
125 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size);
126 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag);
127
128 /* helper functions */
129 static int jlink_get_version_info(void);
130
131 #ifdef _DEBUG_USB_COMMS_
132 static void jlink_debug_buffer(uint8_t *buffer, int length);
133 #endif
134
135 static enum tap_state jlink_last_state = TAP_RESET;
136
137 static jlink_jtag_t* jlink_jtag_handle;
138
139 /***************************************************************************/
140 /* External interface implementation */
141
142 jtag_interface_t jlink_interface =
143 {
144         .name = "jlink",
145         .execute_queue = jlink_execute_queue,
146         .speed = jlink_speed,
147         .speed_div = jlink_speed_div,
148         .khz = jlink_khz,
149         .register_commands = jlink_register_commands,
150         .init = jlink_init,
151         .quit = jlink_quit
152 };
153
154 static void jlink_execute_runtest(jtag_command_t *cmd)
155 {
156         DEBUG_JTAG_IO("runtest %i cycles, end in %i",
157                         cmd->cmd.runtest->num_cycles,
158                         cmd->cmd.runtest->end_state);
159
160         jlink_end_state(cmd->cmd.runtest->end_state);
161
162         jlink_runtest(cmd->cmd.runtest->num_cycles);
163 }
164
165 static void jlink_execute_statemove(jtag_command_t *cmd)
166 {
167         DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
168
169         jlink_end_state(cmd->cmd.statemove->end_state);
170         jlink_state_move();
171 }
172
173 static void jlink_execute_pathmove(jtag_command_t *cmd)
174 {
175         DEBUG_JTAG_IO("pathmove: %i states, end in %i",
176                 cmd->cmd.pathmove->num_states,
177                 cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
178
179         jlink_path_move(cmd->cmd.pathmove->num_states,
180                         cmd->cmd.pathmove->path);
181 }
182
183 static void jlink_execute_scan(jtag_command_t *cmd)
184 {
185         int scan_size;
186         enum scan_type type;
187         uint8_t *buffer;
188
189         DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
190
191         jlink_end_state(cmd->cmd.scan->end_state);
192
193         scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
194         DEBUG_JTAG_IO("scan input, length = %d", scan_size);
195
196 #ifdef _DEBUG_USB_COMMS_
197         jlink_debug_buffer(buffer, (scan_size + 7) / 8);
198 #endif
199         type = jtag_scan_type(cmd->cmd.scan);
200         jlink_scan(cmd->cmd.scan->ir_scan,
201                         type, buffer, scan_size, cmd->cmd.scan);
202 }
203
204 static void jlink_execute_reset(jtag_command_t *cmd)
205 {
206         DEBUG_JTAG_IO("reset trst: %i srst %i",
207                         cmd->cmd.reset->trst, cmd->cmd.reset->srst);
208
209         jlink_tap_execute();
210         jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
211         jlink_tap_execute();
212 }
213
214 static void jlink_execute_sleep(jtag_command_t *cmd)
215 {
216         DEBUG_JTAG_IO("sleep %i", cmd->cmd.sleep->us);
217         jlink_tap_execute();
218         jtag_sleep(cmd->cmd.sleep->us);
219 }
220
221 static void jlink_execute_command(jtag_command_t *cmd)
222 {
223         switch (cmd->type)
224         {
225         case JTAG_RUNTEST:   jlink_execute_runtest(cmd); break;
226         case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
227         case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
228         case JTAG_SCAN:      jlink_execute_scan(cmd); break;
229         case JTAG_RESET:     jlink_execute_reset(cmd); break;
230         case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
231         default:
232                 LOG_ERROR("BUG: unknown JTAG command type encountered");
233                 exit(-1);
234         }
235 }
236
237 static int jlink_execute_queue(void)
238 {
239         jtag_command_t *cmd = jtag_command_queue;
240
241         while (cmd != NULL)
242         {
243                 jlink_execute_command(cmd);
244                 cmd = cmd->next;
245         }
246
247         return jlink_tap_execute();
248 }
249
250 /* Sets speed in kHz. */
251 static int jlink_speed(int speed)
252 {
253         int result;
254
255         if (speed > JLINK_MAX_SPEED)
256         {
257                 LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
258                                 speed, JLINK_MAX_SPEED);
259                 return ERROR_OK;
260         }
261
262         /* check for RTCK setting */
263         if (speed == 0)
264                 speed = -1;
265
266         usb_out_buffer[0] = EMU_CMD_SET_SPEED;
267         usb_out_buffer[1] = (speed >> 0) & 0xff;
268         usb_out_buffer[2] = (speed >> 8) & 0xff;
269
270         result = jlink_usb_write(jlink_jtag_handle, 3);
271         if (result != 3)
272         {
273                 LOG_ERROR("J-Link setting speed failed (%d)", result);
274                 return ERROR_JTAG_DEVICE_ERROR;
275         }
276
277         return ERROR_OK;
278 }
279
280 static int jlink_speed_div(int speed, int* khz)
281 {
282         *khz = speed;
283
284         return ERROR_OK;
285 }
286
287 static int jlink_khz(int khz, int *jtag_speed)
288 {
289         *jtag_speed = khz;
290
291         return ERROR_OK;
292 }
293
294 static int jlink_register_commands(struct command_context_s *cmd_ctx)
295 {
296
297         register_command(cmd_ctx, NULL, "jlink_info",
298                 &jlink_handle_jlink_info_command, COMMAND_EXEC,
299                 "query jlink info");
300         register_command(cmd_ctx, NULL, "jlink_hw_jtag",
301                 &jlink_handle_jlink_hw_jtag_command, COMMAND_EXEC,
302                 "set/get jlink hw jtag command version [2 | 3]");
303         return ERROR_OK;
304 }
305
306 static int jlink_init(void)
307 {
308         int i;
309
310         jlink_jtag_handle = jlink_usb_open();
311
312         if (jlink_jtag_handle == 0)
313         {
314                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
315                 return ERROR_JTAG_INIT_FAILED;
316         }
317         
318         /*
319          *  The next three instructions were added after discovering a problem while using an oscilloscope.  For the V8
320          *      SAM-ICE dongle (and likely other j-link device variants), the reset line to the target microprocessor was found to
321          *      cycle only intermittently during emulator startup (even after encountering the downstream reset instruction later
322          *      in the code).  This was found to create two issues:  1) In general it is a bad practice to not reset a CPU to a known
323          *      state when starting an emulator and 2) something critical happens inside the dongle when it does the first read
324          *      following a new USB session.  Keeping the processor in reset during the first read collecting version information
325          *      seems to prevent errant "J-Link command EMU_CMD_VERSION failed" issues.
326          */
327         
328         LOG_INFO("J-Link initialization started / target CPU reset initiated");
329         jlink_simple_command(EMU_CMD_HW_TRST0);
330         jlink_simple_command(EMU_CMD_HW_RESET0);
331         usleep(1000);
332
333         jlink_hw_jtag_version = 2;
334
335         if (jlink_get_version_info() == ERROR_OK)
336         {
337                 /* attempt to get status */
338                 jlink_get_status();
339         }
340
341         LOG_INFO("J-Link JTAG Interface ready");
342
343         jlink_reset(0, 0);
344         jtag_sleep(3000);
345         jlink_tap_init();
346         jlink_speed(jtag_get_speed());
347
348         /* v5/6 jlink seems to have an issue if the first tap move
349          * is not divisible by 8, so we send a TLR on first power up */
350         for (i = 0; i < 8; i++) {
351                 jlink_tap_append_step(1, 0);
352         }
353         jlink_tap_execute();
354
355         return ERROR_OK;
356 }
357
358 static int jlink_quit(void)
359 {
360         jlink_usb_close(jlink_jtag_handle);
361         return ERROR_OK;
362 }
363
364 /***************************************************************************/
365 /* Queue command implementations */
366
367 static void jlink_end_state(tap_state_t state)
368 {
369         if (tap_is_state_stable(state))
370         {
371                 tap_set_end_state(state);
372         }
373         else
374         {
375                 LOG_ERROR("BUG: %i is not a valid end state", state);
376                 exit(-1);
377         }
378 }
379
380 /* Goes to the end state. */
381 static void jlink_state_move(void)
382 {
383         int i;
384         int tms = 0;
385         uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
386         uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
387
388         for (i = 0; i < tms_scan_bits; i++)
389         {
390                 tms = (tms_scan >> i) & 1;
391                 jlink_tap_append_step(tms, 0);
392         }
393
394         tap_set_state(tap_get_end_state());
395 }
396
397 static void jlink_path_move(int num_states, tap_state_t *path)
398 {
399         int i;
400
401         for (i = 0; i < num_states; i++)
402         {
403                 if (path[i] == tap_state_transition(tap_get_state(), false))
404                 {
405                         jlink_tap_append_step(0, 0);
406                 }
407                 else if (path[i] == tap_state_transition(tap_get_state(), true))
408                 {
409                         jlink_tap_append_step(1, 0);
410                 }
411                 else
412                 {
413                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
414                         exit(-1);
415                 }
416
417                 tap_set_state(path[i]);
418         }
419
420         tap_set_end_state(tap_get_state());
421 }
422
423 static void jlink_runtest(int num_cycles)
424 {
425         int i;
426
427         tap_state_t saved_end_state = tap_get_end_state();
428
429         jlink_tap_ensure_space(1,num_cycles + 16);
430
431         /* only do a state_move when we're not already in IDLE */
432         if (tap_get_state() != TAP_IDLE)
433         {
434                 jlink_end_state(TAP_IDLE);
435                 jlink_state_move();
436 //              num_cycles--;
437         }
438
439         /* execute num_cycles */
440         for (i = 0; i < num_cycles; i++)
441         {
442                 jlink_tap_append_step(0, 0);
443         }
444
445         /* finish in end_state */
446         jlink_end_state(saved_end_state);
447         if (tap_get_state() != tap_get_end_state())
448         {
449                 jlink_state_move();
450         }
451 }
452
453 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, scan_command_t *command)
454 {
455         tap_state_t saved_end_state;
456
457         jlink_tap_ensure_space(1, scan_size + 16);
458
459         saved_end_state = tap_get_end_state();
460
461         /* Move to appropriate scan state */
462         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
463
464         /* Only move if we're not already there */
465         if (tap_get_state() != tap_get_end_state())
466                 jlink_state_move();
467
468         jlink_end_state(saved_end_state);
469
470         /* Scan */
471         jlink_tap_append_scan(scan_size, buffer, command);
472
473         /* We are in Exit1, go to Pause */
474         jlink_tap_append_step(0, 0);
475
476         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
477
478         if (tap_get_state() != tap_get_end_state())
479         {
480                 jlink_state_move();
481         }
482 }
483
484 static void jlink_reset(int trst, int srst)
485 {
486         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
487
488         /* Signals are active low */
489         if (srst == 0)
490         {
491                 jlink_simple_command(EMU_CMD_HW_RESET1);
492         }
493         if (srst == 1)
494         {
495                 jlink_simple_command(EMU_CMD_HW_RESET0);
496         }
497
498         if (trst == 1)
499         {
500                 jlink_simple_command(EMU_CMD_HW_TRST0);
501         }
502
503         if (trst == 0)
504         {
505                 jlink_simple_command(EMU_CMD_HW_TRST1);
506         }
507 }
508
509 static void jlink_simple_command(uint8_t command)
510 {
511         int result;
512
513         DEBUG_JTAG_IO("0x%02x", command);
514
515         usb_out_buffer[0] = command;
516         result = jlink_usb_write(jlink_jtag_handle, 1);
517
518         if (result != 1)
519         {
520                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
521         }
522 }
523
524 static int jlink_get_status(void)
525 {
526         int result;
527
528         jlink_simple_command(EMU_CMD_GET_STATE);
529
530         result = jlink_usb_read(jlink_jtag_handle, 8);
531         if (result != 8)
532         {
533                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
534                 return ERROR_JTAG_DEVICE_ERROR;
535         }
536
537         int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
538         LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
539                 vref / 1000, vref % 1000, \
540                 usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
541                 usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
542
543         if (vref < 1500)
544                 LOG_ERROR("Vref too low. Check Target Power\n");
545
546         return ERROR_OK;
547 }
548
549 static int jlink_get_version_info(void)
550 {
551         int result;
552         int len;
553         uint32_t jlink_caps, jlink_max_size;
554
555         /* query hardware version */
556         jlink_simple_command(EMU_CMD_VERSION);
557
558         result = jlink_usb_read(jlink_jtag_handle, 2);
559         if (2 != result)
560         {
561                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
562                 return ERROR_JTAG_DEVICE_ERROR;
563         }
564
565         len = buf_get_u32(usb_in_buffer, 0, 16);
566         if (len > JLINK_IN_BUFFER_SIZE)
567         {
568                 LOG_ERROR("J-Link command EMU_CMD_VERSION impossible return length 0x%0x", len);
569                 len = JLINK_IN_BUFFER_SIZE;
570         }
571
572         result = jlink_usb_read(jlink_jtag_handle, len);
573         if (result != len)
574         {
575                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
576                 return ERROR_JTAG_DEVICE_ERROR;
577         }
578
579         usb_in_buffer[result] = 0;
580         LOG_INFO("%s", (char *)usb_in_buffer);
581
582         /* query hardware capabilities */
583         jlink_simple_command(EMU_CMD_GET_CAPS);
584
585         result = jlink_usb_read(jlink_jtag_handle, 4);
586         if (4 != result)
587         {
588                 LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
589                 return ERROR_JTAG_DEVICE_ERROR;
590         }
591
592         jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
593         LOG_INFO("JLink caps 0x%x", (unsigned)jlink_caps);
594
595         if (jlink_caps & (1 << EMU_CAP_GET_HW_VERSION))
596         {
597                 /* query hardware version */
598                 jlink_simple_command(EMU_CMD_GET_HW_VERSION);
599
600                 result = jlink_usb_read(jlink_jtag_handle, 4);
601                 if (4 != result)
602                 {
603                         LOG_ERROR("J-Link command EMU_CMD_GET_HW_VERSION failed (%d)\n", result);
604                         return ERROR_JTAG_DEVICE_ERROR;
605                 }
606
607                 uint32_t jlink_hw_version = buf_get_u32(usb_in_buffer, 0, 32);
608                 uint32_t major_revision = (jlink_hw_version / 10000) % 100;
609                 if (major_revision >= 5)
610                         jlink_hw_jtag_version = 3;
611
612                 LOG_INFO("JLink hw version %i", (int)jlink_hw_version);
613         }
614
615         if (jlink_caps & (1 << EMU_CAP_GET_MAX_BLOCK_SIZE))
616         {
617                 /* query hardware maximum memory block */
618                 jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
619
620                 result = jlink_usb_read(jlink_jtag_handle, 4);
621                 if (4 != result)
622                 {
623                         LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
624                         return ERROR_JTAG_DEVICE_ERROR;
625                 }
626
627                 jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
628                 LOG_INFO("JLink max mem block %i", (int)jlink_max_size);
629         }
630
631         return ERROR_OK;
632 }
633
634 static int jlink_handle_jlink_info_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
635 {
636         if (jlink_get_version_info() == ERROR_OK)
637         {
638                 /* attempt to get status */
639                 jlink_get_status();
640         }
641
642         return ERROR_OK;
643 }
644
645 static int jlink_handle_jlink_hw_jtag_command(struct command_context_s *cmd_ctx, char *cmd, char **args, int argc)
646 {
647         switch (argc) {
648         case 0:
649                 command_print(cmd_ctx, "jlink hw jtag  %i", jlink_hw_jtag_version);
650                 break;
651         case 1: {
652                 int request_version = atoi(args[0]);
653                 switch (request_version) {
654                 case 2: case 3:
655                         jlink_hw_jtag_version = request_version;
656                         break;
657                 default:
658                         return ERROR_COMMAND_SYNTAX_ERROR;
659                 }
660                 break;
661         }
662         default:
663                 return ERROR_COMMAND_SYNTAX_ERROR;
664         }
665
666         return ERROR_OK;
667 }
668
669 /***************************************************************************/
670 /* J-Link tap functions */
671
672
673 static unsigned tap_length = 0;
674 static uint8_t tms_buffer[JLINK_TAP_BUFFER_SIZE];
675 static uint8_t tdi_buffer[JLINK_TAP_BUFFER_SIZE];
676 static uint8_t tdo_buffer[JLINK_TAP_BUFFER_SIZE];
677
678 typedef struct
679 {
680         int first;      /* First bit position in tdo_buffer to read */
681         int length; /* Number of bits to read */
682         scan_command_t *command; /* Corresponding scan command */
683         uint8_t *buffer;
684 } pending_scan_result_t;
685
686 #define MAX_PENDING_SCAN_RESULTS 256
687
688 static int pending_scan_results_length;
689 static pending_scan_result_t pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
690
691 static void jlink_tap_init(void)
692 {
693         tap_length = 0;
694         pending_scan_results_length = 0;
695 }
696
697 static void jlink_tap_ensure_space(int scans, int bits)
698 {
699         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
700         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length - 32;
701
702         if (scans > available_scans || bits > available_bits)
703         {
704                 jlink_tap_execute();
705         }
706 }
707
708 static void jlink_tap_append_step(int tms, int tdi)
709 {
710         int index = tap_length / 8;
711
712         if (index >= JLINK_TAP_BUFFER_SIZE)
713         {
714                 LOG_ERROR("jlink_tap_append_step: overflow");
715                 *(uint32_t *)0xFFFFFFFF = 0;
716                 exit(-1);
717         }
718
719         int bit_index = tap_length % 8;
720         uint8_t bit = 1 << bit_index;
721
722         // we do not pad TMS, so be sure to initialize all bits
723         if (0 == bit_index)
724         {
725                 tms_buffer[index] = tdi_buffer[index] = 0;
726         }
727
728         if (tms)
729                 tms_buffer[index] |= bit;
730         else
731                 tms_buffer[index] &= ~bit;
732
733         if (tdi)
734                 tdi_buffer[index] |= bit;
735         else
736                 tdi_buffer[index] &= ~bit;
737
738         tap_length++;
739 }
740
741 static void jlink_tap_append_scan(int length, uint8_t *buffer, scan_command_t *command)
742 {
743         pending_scan_result_t *pending_scan_result =
744                 &pending_scan_results_buffer[pending_scan_results_length];
745         int i;
746
747         pending_scan_result->first = tap_length;
748         pending_scan_result->length = length;
749         pending_scan_result->command = command;
750         pending_scan_result->buffer = buffer;
751
752         for (i = 0; i < length; i++)
753         {
754                 int tms = (i < (length - 1)) ? 0 : 1;
755                 int tdi = (buffer[i / 8] & (1 << (i % 8))) != 0;
756                 jlink_tap_append_step(tms, tdi);
757         }
758         pending_scan_results_length++;
759 }
760
761 /* Pad and send a tap sequence to the device, and receive the answer.
762  * For the purpose of padding we assume that we are in idle or pause state. */
763 static int jlink_tap_execute(void)
764 {
765         int byte_length;
766         int i;
767         int result;
768
769         if (!tap_length)
770                 return ERROR_OK;
771
772         /* JLink returns an extra NULL in packet when size of in message is a multiple of 64, creates problems with usb comms */
773         /* WARNING This will interfere with tap state counting */
774         while ((TAP_SCAN_BYTES(tap_length)%64) == 0)
775         {
776                 jlink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
777         }
778
779         // number of full bytes (plus one if some would be left over)
780         byte_length = TAP_SCAN_BYTES(tap_length);
781
782         bool use_jtag3 = jlink_hw_jtag_version >= 3;
783         usb_out_buffer[0] = use_jtag3 ? EMU_CMD_HW_JTAG3 : EMU_CMD_HW_JTAG2;
784         usb_out_buffer[1] = 0;
785         usb_out_buffer[2] = (tap_length >> 0) & 0xff;
786         usb_out_buffer[3] = (tap_length >> 8) & 0xff;
787         memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
788         memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
789
790         jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
791                         tap_length, jlink_last_state);
792
793         result = jlink_usb_message(jlink_jtag_handle, 4 + 2 * byte_length, byte_length);
794         if (result != byte_length)
795         {
796                 LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
797                 jlink_tap_init();
798                 return ERROR_JTAG_QUEUE_FAILED;
799         }
800
801         memcpy(tdo_buffer, usb_in_buffer, byte_length);
802
803         for (i = 0; i < pending_scan_results_length; i++)
804         {
805                 pending_scan_result_t *pending_scan_result = &pending_scan_results_buffer[i];
806                 uint8_t *buffer = pending_scan_result->buffer;
807                 int length = pending_scan_result->length;
808                 int first = pending_scan_result->first;
809                 scan_command_t *command = pending_scan_result->command;
810
811                 /* Copy to buffer */
812                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
813
814                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
815
816 #ifdef _DEBUG_USB_COMMS_
817                 jlink_debug_buffer(buffer, TAP_SCAN_BYTES(length));
818 #endif
819
820                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
821                 {
822                         jlink_tap_init();
823                         return ERROR_JTAG_QUEUE_FAILED;
824                 }
825
826                 if (pending_scan_result->buffer != NULL)
827                 {
828                         free(pending_scan_result->buffer);
829                 }
830         }
831
832         jlink_tap_init();
833         return ERROR_OK;
834 }
835
836 static struct usb_device* find_jlink_device(void)
837 {
838         struct usb_bus *busses;
839         struct usb_bus *bus;
840         struct usb_device *dev;
841
842         usb_find_busses();
843         usb_find_devices();
844
845         busses = usb_get_busses();
846
847         /* find jlink_jtag device in usb bus */
848
849         for (bus = busses; bus; bus = bus->next)
850         {
851                 for (dev = bus->devices; dev; dev = dev->next)
852                 {
853                         if ((dev->descriptor.idVendor == VID) && (dev->descriptor.idProduct == PID)) {
854                                 return dev;
855                         }
856                 }
857         }
858
859         return NULL;
860 }
861
862 /*****************************************************************************/
863 /* JLink USB low-level functions */
864
865 static jlink_jtag_t* jlink_usb_open()
866 {
867         struct usb_device *dev;
868
869         jlink_jtag_t *result;
870
871         result = (jlink_jtag_t*) malloc(sizeof(jlink_jtag_t));
872
873         usb_init();
874
875         if ((dev = find_jlink_device()) == NULL) {
876                 free(result);
877                 return NULL;
878         }
879
880         result->usb_handle = usb_open(dev);
881
882         if (result->usb_handle)
883         {
884         
885                 /* BE ***VERY CAREFUL*** ABOUT MAKING CHANGES IN THIS AREA!!!!!!!!!!!
886                  * The behavior of libusb is not completely consistent across Windows, Linux, and Mac OS X platforms.  The actions taken
887                  * in the following compiler conditionals may not agree with published documentation for libusb, but were found
888                  * to be necessary through trials and tribulations.  Even little tweaks can break one or more platforms, so if you do make changes
889                  * test them carefully on all platforms before committing them!
890                  */
891
892 #if IS_WIN32 == 0
893
894                 usb_reset(result->usb_handle);
895
896 #if IS_DARWIN == 0
897
898                 int timeout = 5;
899
900                 /* reopen jlink after usb_reset
901                  * on win32 this may take a second or two to re-enumerate */
902                 while ((dev = find_jlink_device()) == NULL)
903                 {
904                         usleep(1000);
905                         timeout--;
906                         if (!timeout) {
907                                 break;
908                         }
909                 }
910
911                 if (dev == NULL)
912                 {
913                         free(result);
914                         return NULL;
915                 }
916
917                 result->usb_handle = usb_open(dev);
918 #endif
919
920 #endif
921
922                 if (result->usb_handle)
923                 {
924                         /* usb_set_configuration required under win32 */
925                         usb_set_configuration(result->usb_handle, dev->config[0].bConfigurationValue);
926                         usb_claim_interface(result->usb_handle, 0);
927
928 #if 0
929                         /*
930                          * This makes problems under Mac OS X. And is not needed
931                          * under Windows. Hopefully this will not break a linux build
932                          */
933                         usb_set_altinterface(result->usb_handle, 0);
934 #endif
935                         struct usb_interface *iface = dev->config->interface;
936                         struct usb_interface_descriptor *desc = iface->altsetting;
937                         for (int i = 0; i < desc->bNumEndpoints; i++)
938                         {
939                                 uint8_t epnum = desc->endpoint[i].bEndpointAddress;
940                                 bool is_input = epnum & 0x80;
941                                 LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
942                                 if (is_input)
943                                         jlink_read_ep = epnum;
944                                 else
945                                         jlink_write_ep = epnum;
946                         }
947
948                         return result;
949                 }
950         }
951
952         free(result);
953         return NULL;
954 }
955
956 static void jlink_usb_close(jlink_jtag_t *jlink_jtag)
957 {
958         usb_close(jlink_jtag->usb_handle);
959         free(jlink_jtag);
960 }
961
962 /* Send a message and receive the reply. */
963 static int jlink_usb_message(jlink_jtag_t *jlink_jtag, int out_length, int in_length)
964 {
965         int result;
966
967         result = jlink_usb_write(jlink_jtag, out_length);
968         if (result != out_length)
969         {
970                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
971                                 out_length, result);
972                 return ERROR_JTAG_DEVICE_ERROR;
973         }
974
975         result = jlink_usb_read(jlink_jtag, in_length);
976         if ((result != in_length) && (result != (in_length + 1)))
977         {
978                 LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
979                                 in_length, result);
980                 return ERROR_JTAG_DEVICE_ERROR;
981         }
982
983         if (jlink_hw_jtag_version < 3)
984                 return result;
985
986         int result2 = ERROR_OK;
987         if (result == in_length)
988         {
989                 /* Must read the result from the EMU too */
990                 result2 = jlink_usb_read_emu_result(jlink_jtag);
991                 if (1 != result2)
992                 {
993                         LOG_ERROR("jlink_usb_read_emu_result retried requested = 1, result=%d, in_length=%i", result2,in_length);
994                         /* Try again once, should only happen if (in_length%64 == 0) */
995                         result2 = jlink_usb_read_emu_result(jlink_jtag);
996                         if (1 != result2)
997                         {
998                                 LOG_ERROR("jlink_usb_read_emu_result failed "
999                                         "(requested = 1, result=%d)", result2);
1000                                 return ERROR_JTAG_DEVICE_ERROR;
1001                         }
1002                 }
1003
1004                 /* Check the result itself */
1005                 result2 = usb_emu_result_buffer[0];
1006         }
1007         else
1008         {
1009                 /* Save the result, then remove it from return value */
1010                 result2 = usb_in_buffer[result--];
1011         }
1012
1013         if (result2)
1014         {
1015                 LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
1016                 return ERROR_JTAG_DEVICE_ERROR;
1017         }
1018
1019         return result;
1020 }
1021
1022 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
1023 static int usb_bulk_with_retries(
1024                 int (*f)(usb_dev_handle *, int, char *, int, int),
1025                 usb_dev_handle *dev, int ep,
1026                 char *bytes, int size, int timeout)
1027 {
1028         int tries = 3, count = 0;
1029
1030         while (tries && (count < size))
1031         {
1032                 int result = f(dev, ep, bytes + count, size - count, timeout);
1033                 if (result > 0)
1034                         count += result;
1035                 else if ((-ETIMEDOUT != result) || !--tries)
1036                         return result;
1037         }
1038         return count;
1039 }
1040
1041 static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
1042                                char *buff, int size, int timeout)
1043 {
1044         /* usb_bulk_write() takes const char *buff */
1045         return usb_bulk_write(dev, ep, buff, size, timeout);
1046 }
1047
1048 static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
1049                 char *bytes, int size, int timeout)
1050 {
1051         return usb_bulk_with_retries(&wrap_usb_bulk_write,
1052                         dev, ep, bytes, size, timeout);
1053 }
1054
1055 static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
1056                 char *bytes, int size, int timeout)
1057 {
1058         return usb_bulk_with_retries(&usb_bulk_read,
1059                         dev, ep, bytes, size, timeout);
1060 }
1061
1062 /* Write data from out_buffer to USB. */
1063 static int jlink_usb_write(jlink_jtag_t *jlink_jtag, int out_length)
1064 {
1065         int result;
1066
1067         if (out_length > JLINK_OUT_BUFFER_SIZE)
1068         {
1069                 LOG_ERROR("jlink_jtag_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
1070                 return -1;
1071         }
1072
1073         result = usb_bulk_write_ex(jlink_jtag->usb_handle, jlink_write_ep,
1074                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
1075
1076         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
1077
1078 #ifdef _DEBUG_USB_COMMS_
1079         jlink_debug_buffer(usb_out_buffer, out_length);
1080 #endif
1081         return result;
1082 }
1083
1084 /* Read data from USB into in_buffer. */
1085 static int jlink_usb_read(jlink_jtag_t *jlink_jtag, int expected_size)
1086 {
1087         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, jlink_read_ep,
1088                 (char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
1089
1090         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
1091
1092 #ifdef _DEBUG_USB_COMMS_
1093         jlink_debug_buffer(usb_in_buffer, result);
1094 #endif
1095         return result;
1096 }
1097
1098 /* Read the result from the previous EMU cmd into result_buffer. */
1099 static int jlink_usb_read_emu_result(jlink_jtag_t *jlink_jtag)
1100 {
1101         int result = usb_bulk_read_ex(jlink_jtag->usb_handle, jlink_read_ep,
1102                 (char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
1103                 JLINK_USB_TIMEOUT);
1104
1105         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
1106
1107 #ifdef _DEBUG_USB_COMMS_
1108         jlink_debug_buffer(usb_emu_result_buffer, result);
1109 #endif
1110         return result;
1111 }
1112
1113 #ifdef _DEBUG_USB_COMMS_
1114 #define BYTES_PER_LINE  16
1115
1116 static void jlink_debug_buffer(uint8_t *buffer, int length)
1117 {
1118         char line[81];
1119         char s[4];
1120         int i;
1121         int j;
1122
1123         for (i = 0; i < length; i += BYTES_PER_LINE)
1124         {
1125                 snprintf(line, 5, "%04x", i);
1126                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
1127                 {
1128                         snprintf(s, 4, " %02x", buffer[j]);
1129                         strcat(line, s);
1130                 }
1131                 LOG_DEBUG("%s", line);
1132         }
1133 }
1134 #endif
1135