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JTAG/drivers: cleanup jtag_interface structs
[openocd] / src / jtag / drivers / 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 <jtag/interface.h>
29 #include <jtag/commands.h>
30 #include "usb_common.h"
31
32
33 #define VID 0x1366
34 #define PID 0x0101
35
36 #define JLINK_WRITE_ENDPOINT    0x02
37 #define JLINK_READ_ENDPOINT             0x81
38
39 static unsigned int jlink_write_ep = JLINK_WRITE_ENDPOINT;
40 static unsigned int jlink_read_ep = JLINK_READ_ENDPOINT;
41 static unsigned int jlink_hw_jtag_version = 2;
42
43 #define JLINK_USB_TIMEOUT               1000
44
45 // See Section 1.3.2 of the Segger JLink USB protocol manual
46 /* 2048 is the max value we can use here */
47 //#define JLINK_TAP_BUFFER_SIZE 2048
48 #define JLINK_TAP_BUFFER_SIZE 256
49 //#define JLINK_TAP_BUFFER_SIZE 384
50
51 #define JLINK_IN_BUFFER_SIZE                    2048
52 #define JLINK_OUT_BUFFER_SIZE                   2*2048 + 4
53 #define JLINK_EMU_RESULT_BUFFER_SIZE    64
54
55 /* Global USB buffers */
56 static uint8_t usb_in_buffer[JLINK_IN_BUFFER_SIZE];
57 static uint8_t usb_out_buffer[JLINK_OUT_BUFFER_SIZE];
58 static uint8_t usb_emu_result_buffer[JLINK_EMU_RESULT_BUFFER_SIZE];
59
60 /* Constants for JLink command */
61 #define EMU_CMD_VERSION         0x01
62 #define EMU_CMD_SET_SPEED               0x05
63 #define EMU_CMD_GET_STATE               0x07
64 #define EMU_CMD_HW_CLOCK                        0xc8
65 #define EMU_CMD_HW_TMS0                 0xc9
66 #define EMU_CMD_HW_TMS1                 0xca
67 #define EMU_CMD_HW_JTAG2                0xce
68 #define EMU_CMD_HW_JTAG3                0xcf
69 #define EMU_CMD_GET_MAX_MEM_BLOCK       0xd4
70 #define EMU_CMD_HW_RESET0               0xdc
71 #define EMU_CMD_HW_RESET1               0xdd
72 #define EMU_CMD_HW_TRST0                0xde
73 #define EMU_CMD_HW_TRST1                0xdf
74 #define EMU_CMD_GET_CAPS                0xe8
75 #define EMU_CMD_GET_HW_VERSION  0xf0
76
77 /* bits return from EMU_CMD_GET_CAPS */
78 #define EMU_CAP_GET_HW_VERSION          1
79 #define EMU_CAP_GET_MAX_BLOCK_SIZE      11
80
81 /* max speed 12MHz v5.0 jlink */
82 #define JLINK_MAX_SPEED 12000
83
84 /* Queue command functions */
85 static void jlink_end_state(tap_state_t state);
86 static void jlink_state_move(void);
87 static void jlink_path_move(int num_states, tap_state_t *path);
88 static void jlink_runtest(int num_cycles);
89 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command);
90 static void jlink_reset(int trst, int srst);
91 static void jlink_simple_command(uint8_t command);
92 static int jlink_get_status(void);
93
94 /* J-Link tap buffer functions */
95 static void jlink_tap_init(void);
96 static int jlink_tap_execute(void);
97 static void jlink_tap_ensure_space(int scans, int bits);
98 static void jlink_tap_append_step(int tms, int tdi);
99 static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command);
100
101 /* Jlink lowlevel functions */
102 struct jlink {
103         struct usb_dev_handle* usb_handle;
104 };
105
106 static struct jlink *jlink_usb_open(void);
107 static void jlink_usb_close(struct jlink *jlink);
108 static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length);
109 static int jlink_usb_write(struct jlink *jlink, int out_length);
110 static int jlink_usb_read(struct jlink *jlink, int expected_size);
111 static int jlink_usb_read_emu_result(struct jlink *jlink);
112
113 /* helper functions */
114 static int jlink_get_version_info(void);
115
116 #ifdef _DEBUG_USB_COMMS_
117 static void jlink_debug_buffer(uint8_t *buffer, int length);
118 #endif
119
120 static enum tap_state jlink_last_state = TAP_RESET;
121
122 static struct jlink* jlink_handle;
123
124 /***************************************************************************/
125 /* External interface implementation */
126
127 static void jlink_execute_runtest(struct jtag_command *cmd)
128 {
129         DEBUG_JTAG_IO("runtest %i cycles, end in %i",
130                         cmd->cmd.runtest->num_cycles,
131                         cmd->cmd.runtest->end_state);
132
133         jlink_end_state(cmd->cmd.runtest->end_state);
134
135         jlink_runtest(cmd->cmd.runtest->num_cycles);
136 }
137
138 static void jlink_execute_statemove(struct jtag_command *cmd)
139 {
140         DEBUG_JTAG_IO("statemove end in %i", cmd->cmd.statemove->end_state);
141
142         jlink_end_state(cmd->cmd.statemove->end_state);
143         jlink_state_move();
144 }
145
146 static void jlink_execute_pathmove(struct jtag_command *cmd)
147 {
148         DEBUG_JTAG_IO("pathmove: %i states, end in %i",
149                 cmd->cmd.pathmove->num_states,
150                 cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
151
152         jlink_path_move(cmd->cmd.pathmove->num_states,
153                         cmd->cmd.pathmove->path);
154 }
155
156 static void jlink_execute_scan(struct jtag_command *cmd)
157 {
158         int scan_size;
159         enum scan_type type;
160         uint8_t *buffer;
161
162         DEBUG_JTAG_IO("scan end in %s", tap_state_name(cmd->cmd.scan->end_state));
163
164         jlink_end_state(cmd->cmd.scan->end_state);
165
166         scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
167         DEBUG_JTAG_IO("scan input, length = %d", scan_size);
168
169 #ifdef _DEBUG_USB_COMMS_
170         jlink_debug_buffer(buffer, (scan_size + 7) / 8);
171 #endif
172         type = jtag_scan_type(cmd->cmd.scan);
173         jlink_scan(cmd->cmd.scan->ir_scan,
174                         type, buffer, scan_size, cmd->cmd.scan);
175 }
176
177 static void jlink_execute_reset(struct jtag_command *cmd)
178 {
179         DEBUG_JTAG_IO("reset trst: %i srst %i",
180                         cmd->cmd.reset->trst, cmd->cmd.reset->srst);
181
182         jlink_tap_execute();
183         jlink_reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
184         jlink_tap_execute();
185 }
186
187 static void jlink_execute_sleep(struct jtag_command *cmd)
188 {
189         DEBUG_JTAG_IO("sleep %" PRIi32 "", cmd->cmd.sleep->us);
190         jlink_tap_execute();
191         jtag_sleep(cmd->cmd.sleep->us);
192 }
193
194 static void jlink_execute_command(struct jtag_command *cmd)
195 {
196         switch (cmd->type)
197         {
198         case JTAG_RUNTEST:   jlink_execute_runtest(cmd); break;
199         case JTAG_STATEMOVE: jlink_execute_statemove(cmd); break;
200         case JTAG_PATHMOVE:  jlink_execute_pathmove(cmd); break;
201         case JTAG_SCAN:      jlink_execute_scan(cmd); break;
202         case JTAG_RESET:     jlink_execute_reset(cmd); break;
203         case JTAG_SLEEP:     jlink_execute_sleep(cmd); break;
204         default:
205                 LOG_ERROR("BUG: unknown JTAG command type encountered");
206                 exit(-1);
207         }
208 }
209
210 static int jlink_execute_queue(void)
211 {
212         struct jtag_command *cmd = jtag_command_queue;
213
214         while (cmd != NULL)
215         {
216                 jlink_execute_command(cmd);
217                 cmd = cmd->next;
218         }
219
220         return jlink_tap_execute();
221 }
222
223 /* Sets speed in kHz. */
224 static int jlink_speed(int speed)
225 {
226         int result;
227
228         if (speed > JLINK_MAX_SPEED)
229         {
230                 LOG_INFO("Ignoring speed request: %dkHz exceeds %dkHz maximum",
231                                 speed, JLINK_MAX_SPEED);
232                 return ERROR_OK;
233         }
234
235         /* check for RTCK setting */
236         if (speed == 0)
237                 speed = -1;
238
239         usb_out_buffer[0] = EMU_CMD_SET_SPEED;
240         usb_out_buffer[1] = (speed >> 0) & 0xff;
241         usb_out_buffer[2] = (speed >> 8) & 0xff;
242
243         result = jlink_usb_write(jlink_handle, 3);
244         if (result != 3)
245         {
246                 LOG_ERROR("J-Link setting speed failed (%d)", result);
247                 return ERROR_JTAG_DEVICE_ERROR;
248         }
249
250         return ERROR_OK;
251 }
252
253 static int jlink_speed_div(int speed, int* khz)
254 {
255         *khz = speed;
256
257         return ERROR_OK;
258 }
259
260 static int jlink_khz(int khz, int *jtag_speed)
261 {
262         *jtag_speed = khz;
263
264         return ERROR_OK;
265 }
266
267 static int jlink_init(void)
268 {
269         int i;
270
271         jlink_handle = jlink_usb_open();
272
273         if (jlink_handle == 0)
274         {
275                 LOG_ERROR("Cannot find jlink Interface! Please check connection and permissions.");
276                 return ERROR_JTAG_INIT_FAILED;
277         }
278
279         /*
280          *  The next three instructions were added after discovering a problem while using an oscilloscope.  For the V8
281          *      SAM-ICE dongle (and likely other j-link device variants), the reset line to the target microprocessor was found to
282          *      cycle only intermittently during emulator startup (even after encountering the downstream reset instruction later
283          *      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
284          *      state when starting an emulator and 2) something critical happens inside the dongle when it does the first read
285          *      following a new USB session.  Keeping the processor in reset during the first read collecting version information
286          *      seems to prevent errant "J-Link command EMU_CMD_VERSION failed" issues.
287          */
288
289         LOG_INFO("J-Link initialization started / target CPU reset initiated");
290         jlink_simple_command(EMU_CMD_HW_TRST0);
291         jlink_simple_command(EMU_CMD_HW_RESET0);
292         usleep(1000);
293
294         jlink_hw_jtag_version = 2;
295
296         if (jlink_get_version_info() == ERROR_OK)
297         {
298                 /* attempt to get status */
299                 jlink_get_status();
300         }
301
302         LOG_INFO("J-Link JTAG Interface ready");
303
304         jlink_reset(0, 0);
305         jtag_sleep(3000);
306         jlink_tap_init();
307         jlink_speed(jtag_get_speed());
308
309         /* v5/6 jlink seems to have an issue if the first tap move
310          * is not divisible by 8, so we send a TLR on first power up */
311         for (i = 0; i < 8; i++) {
312                 jlink_tap_append_step(1, 0);
313         }
314         jlink_tap_execute();
315
316         return ERROR_OK;
317 }
318
319 static int jlink_quit(void)
320 {
321         jlink_usb_close(jlink_handle);
322         return ERROR_OK;
323 }
324
325 /***************************************************************************/
326 /* Queue command implementations */
327
328 static void jlink_end_state(tap_state_t state)
329 {
330         if (tap_is_state_stable(state))
331         {
332                 tap_set_end_state(state);
333         }
334         else
335         {
336                 LOG_ERROR("BUG: %i is not a valid end state", state);
337                 exit(-1);
338         }
339 }
340
341 /* Goes to the end state. */
342 static void jlink_state_move(void)
343 {
344         int i;
345         int tms = 0;
346         uint8_t tms_scan = tap_get_tms_path(tap_get_state(), tap_get_end_state());
347         uint8_t tms_scan_bits = tap_get_tms_path_len(tap_get_state(), tap_get_end_state());
348
349         for (i = 0; i < tms_scan_bits; i++)
350         {
351                 tms = (tms_scan >> i) & 1;
352                 jlink_tap_append_step(tms, 0);
353         }
354
355         tap_set_state(tap_get_end_state());
356 }
357
358 static void jlink_path_move(int num_states, tap_state_t *path)
359 {
360         int i;
361
362         for (i = 0; i < num_states; i++)
363         {
364                 if (path[i] == tap_state_transition(tap_get_state(), false))
365                 {
366                         jlink_tap_append_step(0, 0);
367                 }
368                 else if (path[i] == tap_state_transition(tap_get_state(), true))
369                 {
370                         jlink_tap_append_step(1, 0);
371                 }
372                 else
373                 {
374                         LOG_ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_name(tap_get_state()), tap_state_name(path[i]));
375                         exit(-1);
376                 }
377
378                 tap_set_state(path[i]);
379         }
380
381         tap_set_end_state(tap_get_state());
382 }
383
384 static void jlink_runtest(int num_cycles)
385 {
386         int i;
387
388         tap_state_t saved_end_state = tap_get_end_state();
389
390         jlink_tap_ensure_space(1,num_cycles + 16);
391
392         /* only do a state_move when we're not already in IDLE */
393         if (tap_get_state() != TAP_IDLE)
394         {
395                 jlink_end_state(TAP_IDLE);
396                 jlink_state_move();
397 //              num_cycles--;
398         }
399
400         /* execute num_cycles */
401         for (i = 0; i < num_cycles; i++)
402         {
403                 jlink_tap_append_step(0, 0);
404         }
405
406         /* finish in end_state */
407         jlink_end_state(saved_end_state);
408         if (tap_get_state() != tap_get_end_state())
409         {
410                 jlink_state_move();
411         }
412 }
413
414 static void jlink_scan(bool ir_scan, enum scan_type type, uint8_t *buffer, int scan_size, struct scan_command *command)
415 {
416         tap_state_t saved_end_state;
417
418         jlink_tap_ensure_space(1, scan_size + 16);
419
420         saved_end_state = tap_get_end_state();
421
422         /* Move to appropriate scan state */
423         jlink_end_state(ir_scan ? TAP_IRSHIFT : TAP_DRSHIFT);
424
425         /* Only move if we're not already there */
426         if (tap_get_state() != tap_get_end_state())
427                 jlink_state_move();
428
429         jlink_end_state(saved_end_state);
430
431         /* Scan */
432         jlink_tap_append_scan(scan_size, buffer, command);
433
434         /* We are in Exit1, go to Pause */
435         jlink_tap_append_step(0, 0);
436
437         tap_set_state(ir_scan ? TAP_IRPAUSE : TAP_DRPAUSE);
438
439         if (tap_get_state() != tap_get_end_state())
440         {
441                 jlink_state_move();
442         }
443 }
444
445 static void jlink_reset(int trst, int srst)
446 {
447         LOG_DEBUG("trst: %i, srst: %i", trst, srst);
448
449         /* Signals are active low */
450         if (srst == 0)
451         {
452                 jlink_simple_command(EMU_CMD_HW_RESET1);
453         }
454         if (srst == 1)
455         {
456                 jlink_simple_command(EMU_CMD_HW_RESET0);
457         }
458
459         if (trst == 1)
460         {
461                 jlink_simple_command(EMU_CMD_HW_TRST0);
462         }
463
464         if (trst == 0)
465         {
466                 jlink_simple_command(EMU_CMD_HW_TRST1);
467         }
468 }
469
470 static void jlink_simple_command(uint8_t command)
471 {
472         int result;
473
474         DEBUG_JTAG_IO("0x%02x", command);
475
476         usb_out_buffer[0] = command;
477         result = jlink_usb_write(jlink_handle, 1);
478
479         if (result != 1)
480         {
481                 LOG_ERROR("J-Link command 0x%02x failed (%d)", command, result);
482         }
483 }
484
485 static int jlink_get_status(void)
486 {
487         int result;
488
489         jlink_simple_command(EMU_CMD_GET_STATE);
490
491         result = jlink_usb_read(jlink_handle, 8);
492         if (result != 8)
493         {
494                 LOG_ERROR("J-Link command EMU_CMD_GET_STATE failed (%d)\n", result);
495                 return ERROR_JTAG_DEVICE_ERROR;
496         }
497
498         int vref = usb_in_buffer[0] + (usb_in_buffer[1] << 8);
499         LOG_INFO("Vref = %d.%d TCK = %d TDI = %d TDO = %d TMS = %d SRST = %d TRST = %d\n", \
500                 vref / 1000, vref % 1000, \
501                 usb_in_buffer[2], usb_in_buffer[3], usb_in_buffer[4], \
502                 usb_in_buffer[5], usb_in_buffer[6], usb_in_buffer[7]);
503
504         if (vref < 1500)
505                 LOG_ERROR("Vref too low. Check Target Power\n");
506
507         return ERROR_OK;
508 }
509
510 static int jlink_get_version_info(void)
511 {
512         int result;
513         int len;
514         uint32_t jlink_caps, jlink_max_size;
515
516         /* query hardware version */
517         jlink_simple_command(EMU_CMD_VERSION);
518
519         result = jlink_usb_read(jlink_handle, 2);
520         if (2 != result)
521         {
522                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
523                 return ERROR_JTAG_DEVICE_ERROR;
524         }
525
526         len = buf_get_u32(usb_in_buffer, 0, 16);
527         if (len > JLINK_IN_BUFFER_SIZE)
528         {
529                 LOG_ERROR("J-Link command EMU_CMD_VERSION impossible return length 0x%0x", len);
530                 len = JLINK_IN_BUFFER_SIZE;
531         }
532
533         result = jlink_usb_read(jlink_handle, len);
534         if (result != len)
535         {
536                 LOG_ERROR("J-Link command EMU_CMD_VERSION failed (%d)\n", result);
537                 return ERROR_JTAG_DEVICE_ERROR;
538         }
539
540         usb_in_buffer[result] = 0;
541         LOG_INFO("%s", (char *)usb_in_buffer);
542
543         /* query hardware capabilities */
544         jlink_simple_command(EMU_CMD_GET_CAPS);
545
546         result = jlink_usb_read(jlink_handle, 4);
547         if (4 != result)
548         {
549                 LOG_ERROR("J-Link command EMU_CMD_GET_CAPS failed (%d)\n", result);
550                 return ERROR_JTAG_DEVICE_ERROR;
551         }
552
553         jlink_caps = buf_get_u32(usb_in_buffer, 0, 32);
554         LOG_INFO("JLink caps 0x%x", (unsigned)jlink_caps);
555
556         if (jlink_caps & (1 << EMU_CAP_GET_HW_VERSION))
557         {
558                 /* query hardware version */
559                 jlink_simple_command(EMU_CMD_GET_HW_VERSION);
560
561                 result = jlink_usb_read(jlink_handle, 4);
562                 if (4 != result)
563                 {
564                         LOG_ERROR("J-Link command EMU_CMD_GET_HW_VERSION failed (%d)\n", result);
565                         return ERROR_JTAG_DEVICE_ERROR;
566                 }
567
568                 uint32_t jlink_hw_version = buf_get_u32(usb_in_buffer, 0, 32);
569                 uint32_t major_revision = (jlink_hw_version / 10000) % 100;
570                 if (major_revision >= 5)
571                         jlink_hw_jtag_version = 3;
572
573                 LOG_INFO("JLink hw version %i", (int)jlink_hw_version);
574         }
575
576         if (jlink_caps & (1 << EMU_CAP_GET_MAX_BLOCK_SIZE))
577         {
578                 /* query hardware maximum memory block */
579                 jlink_simple_command(EMU_CMD_GET_MAX_MEM_BLOCK);
580
581                 result = jlink_usb_read(jlink_handle, 4);
582                 if (4 != result)
583                 {
584                         LOG_ERROR("J-Link command EMU_CMD_GET_MAX_MEM_BLOCK failed (%d)\n", result);
585                         return ERROR_JTAG_DEVICE_ERROR;
586                 }
587
588                 jlink_max_size = buf_get_u32(usb_in_buffer, 0, 32);
589                 LOG_INFO("JLink max mem block %i", (int)jlink_max_size);
590         }
591
592         return ERROR_OK;
593 }
594
595 COMMAND_HANDLER(jlink_handle_jlink_info_command)
596 {
597         if (jlink_get_version_info() == ERROR_OK)
598         {
599                 /* attempt to get status */
600                 jlink_get_status();
601         }
602
603         return ERROR_OK;
604 }
605
606 COMMAND_HANDLER(jlink_handle_jlink_hw_jtag_command)
607 {
608         switch (CMD_ARGC) {
609         case 0:
610                 command_print(CMD_CTX, "jlink hw jtag  %i", jlink_hw_jtag_version);
611                 break;
612         case 1: {
613                 int request_version = atoi(CMD_ARGV[0]);
614                 switch (request_version) {
615                 case 2: case 3:
616                         jlink_hw_jtag_version = request_version;
617                         break;
618                 default:
619                         return ERROR_COMMAND_SYNTAX_ERROR;
620                 }
621                 break;
622         }
623         default:
624                 return ERROR_COMMAND_SYNTAX_ERROR;
625         }
626
627         return ERROR_OK;
628 }
629
630 static const struct command_registration jlink_command_handlers[] = {
631         {
632                 .name = "jlink_info",
633                 .handler = &jlink_handle_jlink_info_command,
634                 .mode = COMMAND_EXEC,
635                 .help = "show jlink info",
636         },
637         {
638                 .name = "jlink_hw_jtag",
639                 .handler = &jlink_handle_jlink_hw_jtag_command,
640                 .mode = COMMAND_EXEC,
641                 .help = "access J-Link HW JTAG command version",
642                 .usage = "[2|3]",
643         },
644         COMMAND_REGISTRATION_DONE
645 };
646
647 struct jtag_interface jlink_interface = {
648         .name = "jlink",
649         .commands = jlink_command_handlers,
650
651         .execute_queue = jlink_execute_queue,
652         .speed = jlink_speed,
653         .speed_div = jlink_speed_div,
654         .khz = jlink_khz,
655         .init = jlink_init,
656         .quit = jlink_quit,
657 };
658
659 /***************************************************************************/
660 /* J-Link tap functions */
661
662
663 static unsigned tap_length = 0;
664 static uint8_t tms_buffer[JLINK_TAP_BUFFER_SIZE];
665 static uint8_t tdi_buffer[JLINK_TAP_BUFFER_SIZE];
666 static uint8_t tdo_buffer[JLINK_TAP_BUFFER_SIZE];
667
668 struct pending_scan_result {
669         int first;      /* First bit position in tdo_buffer to read */
670         int length; /* Number of bits to read */
671         struct scan_command *command; /* Corresponding scan command */
672         uint8_t *buffer;
673 };
674
675 #define MAX_PENDING_SCAN_RESULTS 256
676
677 static int pending_scan_results_length;
678 static struct pending_scan_result pending_scan_results_buffer[MAX_PENDING_SCAN_RESULTS];
679
680 static void jlink_tap_init(void)
681 {
682         tap_length = 0;
683         pending_scan_results_length = 0;
684 }
685
686 static void jlink_tap_ensure_space(int scans, int bits)
687 {
688         int available_scans = MAX_PENDING_SCAN_RESULTS - pending_scan_results_length;
689         int available_bits = JLINK_TAP_BUFFER_SIZE * 8 - tap_length - 32;
690
691         if (scans > available_scans || bits > available_bits)
692         {
693                 jlink_tap_execute();
694         }
695 }
696
697 static void jlink_tap_append_step(int tms, int tdi)
698 {
699         int index = tap_length / 8;
700
701         if (index >= JLINK_TAP_BUFFER_SIZE)
702         {
703                 LOG_ERROR("jlink_tap_append_step: overflow");
704                 *(uint32_t *)0xFFFFFFFF = 0;
705                 exit(-1);
706         }
707
708         int bit_index = tap_length % 8;
709         uint8_t bit = 1 << bit_index;
710
711         // we do not pad TMS, so be sure to initialize all bits
712         if (0 == bit_index)
713         {
714                 tms_buffer[index] = tdi_buffer[index] = 0;
715         }
716
717         if (tms)
718                 tms_buffer[index] |= bit;
719         else
720                 tms_buffer[index] &= ~bit;
721
722         if (tdi)
723                 tdi_buffer[index] |= bit;
724         else
725                 tdi_buffer[index] &= ~bit;
726
727         tap_length++;
728 }
729
730 static void jlink_tap_append_scan(int length, uint8_t *buffer, struct scan_command *command)
731 {
732         struct pending_scan_result *pending_scan_result =
733                 &pending_scan_results_buffer[pending_scan_results_length];
734         int i;
735
736         pending_scan_result->first = tap_length;
737         pending_scan_result->length = length;
738         pending_scan_result->command = command;
739         pending_scan_result->buffer = buffer;
740
741         for (i = 0; i < length; i++)
742         {
743                 int tms = (i < (length - 1)) ? 0 : 1;
744                 int tdi = (buffer[i / 8] & (1 << (i % 8))) != 0;
745                 jlink_tap_append_step(tms, tdi);
746         }
747         pending_scan_results_length++;
748 }
749
750 /* Pad and send a tap sequence to the device, and receive the answer.
751  * For the purpose of padding we assume that we are in idle or pause state. */
752 static int jlink_tap_execute(void)
753 {
754         int byte_length;
755         int i;
756         int result;
757
758         if (!tap_length)
759                 return ERROR_OK;
760
761         /* JLink returns an extra NULL in packet when size of incoming
762          * message is a multiple of 64, creates problems with USB comms.
763          * WARNING: This will interfere with tap state counting. */
764         while ((DIV_ROUND_UP(tap_length, 8) % 64) == 0)
765         {
766                 jlink_tap_append_step((tap_get_state() == TAP_RESET)?1:0, 0);
767         }
768
769         // number of full bytes (plus one if some would be left over)
770         byte_length = DIV_ROUND_UP(tap_length, 8);
771
772         bool use_jtag3 = jlink_hw_jtag_version >= 3;
773         usb_out_buffer[0] = use_jtag3 ? EMU_CMD_HW_JTAG3 : EMU_CMD_HW_JTAG2;
774         usb_out_buffer[1] = 0;
775         usb_out_buffer[2] = (tap_length >> 0) & 0xff;
776         usb_out_buffer[3] = (tap_length >> 8) & 0xff;
777         memcpy(usb_out_buffer + 4, tms_buffer, byte_length);
778         memcpy(usb_out_buffer + 4 + byte_length, tdi_buffer, byte_length);
779
780         jlink_last_state = jtag_debug_state_machine(tms_buffer, tdi_buffer,
781                         tap_length, jlink_last_state);
782
783         result = jlink_usb_message(jlink_handle, 4 + 2 * byte_length, byte_length);
784         if (result != byte_length)
785         {
786                 LOG_ERROR("jlink_tap_execute, wrong result %d (expected %d)", result, byte_length);
787                 jlink_tap_init();
788                 return ERROR_JTAG_QUEUE_FAILED;
789         }
790
791         memcpy(tdo_buffer, usb_in_buffer, byte_length);
792
793         for (i = 0; i < pending_scan_results_length; i++)
794         {
795                 struct pending_scan_result *pending_scan_result = &pending_scan_results_buffer[i];
796                 uint8_t *buffer = pending_scan_result->buffer;
797                 int length = pending_scan_result->length;
798                 int first = pending_scan_result->first;
799                 struct scan_command *command = pending_scan_result->command;
800
801                 /* Copy to buffer */
802                 buf_set_buf(tdo_buffer, first, buffer, 0, length);
803
804                 DEBUG_JTAG_IO("pending scan result, length = %d", length);
805
806 #ifdef _DEBUG_USB_COMMS_
807                 jlink_debug_buffer(buffer, DIV_ROUND_UP(length, 8));
808 #endif
809
810                 if (jtag_read_buffer(buffer, command) != ERROR_OK)
811                 {
812                         jlink_tap_init();
813                         return ERROR_JTAG_QUEUE_FAILED;
814                 }
815
816                 if (pending_scan_result->buffer != NULL)
817                 {
818                         free(pending_scan_result->buffer);
819                 }
820         }
821
822         jlink_tap_init();
823         return ERROR_OK;
824 }
825
826 /*****************************************************************************/
827 /* JLink USB low-level functions */
828
829 static struct jlink* jlink_usb_open()
830 {
831         usb_init();
832
833         const uint16_t vids[] = { VID, 0 };
834         const uint16_t pids[] = { PID, 0 };
835         struct usb_dev_handle *dev;
836         if (jtag_usb_open(vids, pids, &dev) != ERROR_OK)
837                 return NULL;
838
839         /* BE ***VERY CAREFUL*** ABOUT MAKING CHANGES IN THIS
840          * AREA!!!!!!!!!!!  The behavior of libusb is not completely
841          * consistent across Windows, Linux, and Mac OS X platforms.
842          * The actions taken in the following compiler conditionals may
843          * not agree with published documentation for libusb, but were
844          * found to be necessary through trials and tribulations.  Even
845          * little tweaks can break one or more platforms, so if you do
846          * make changes test them carefully on all platforms before
847          * committing them!
848          */
849
850 #if IS_WIN32 == 0
851
852         usb_reset(dev);
853
854 #if IS_DARWIN == 0
855
856         int timeout = 5;
857         /* reopen jlink after usb_reset
858          * on win32 this may take a second or two to re-enumerate */
859         int retval;
860         while ((retval = jtag_usb_open(vids, pids, &dev)) != ERROR_OK)
861         {
862                 usleep(1000);
863                 timeout--;
864                 if (!timeout) {
865                         break;
866                 }
867         }
868         if (ERROR_OK != retval)
869                 return NULL;
870 #endif
871
872 #endif
873
874         /* usb_set_configuration required under win32 */
875         struct usb_device *udev = usb_device(dev);
876         usb_set_configuration(dev, udev->config[0].bConfigurationValue);
877         usb_claim_interface(dev, 0);
878
879 #if 0
880         /*
881          * This makes problems under Mac OS X. And is not needed
882          * under Windows. Hopefully this will not break a linux build
883          */
884         usb_set_altinterface(result->usb_handle, 0);
885 #endif
886         struct usb_interface *iface = udev->config->interface;
887         struct usb_interface_descriptor *desc = iface->altsetting;
888         for (int i = 0; i < desc->bNumEndpoints; i++)
889         {
890                 uint8_t epnum = desc->endpoint[i].bEndpointAddress;
891                 bool is_input = epnum & 0x80;
892                 LOG_DEBUG("usb ep %s %02x", is_input ? "in" : "out", epnum);
893                 if (is_input)
894                         jlink_read_ep = epnum;
895                 else
896                         jlink_write_ep = epnum;
897         }
898
899         struct jlink *result = malloc(sizeof(struct jlink));
900         result->usb_handle = dev;
901         return result;
902 }
903
904 static void jlink_usb_close(struct jlink *jlink)
905 {
906         usb_close(jlink->usb_handle);
907         free(jlink);
908 }
909
910 /* Send a message and receive the reply. */
911 static int jlink_usb_message(struct jlink *jlink, int out_length, int in_length)
912 {
913         int result;
914
915         result = jlink_usb_write(jlink, out_length);
916         if (result != out_length)
917         {
918                 LOG_ERROR("usb_bulk_write failed (requested=%d, result=%d)",
919                                 out_length, result);
920                 return ERROR_JTAG_DEVICE_ERROR;
921         }
922
923         result = jlink_usb_read(jlink, in_length);
924         if ((result != in_length) && (result != (in_length + 1)))
925         {
926                 LOG_ERROR("usb_bulk_read failed (requested=%d, result=%d)",
927                                 in_length, result);
928                 return ERROR_JTAG_DEVICE_ERROR;
929         }
930
931         if (jlink_hw_jtag_version < 3)
932                 return result;
933
934         int result2 = ERROR_OK;
935         if (result == in_length)
936         {
937                 /* Must read the result from the EMU too */
938                 result2 = jlink_usb_read_emu_result(jlink);
939                 if (1 != result2)
940                 {
941                         LOG_ERROR("jlink_usb_read_emu_result retried requested = 1, result=%d, in_length=%i", result2,in_length);
942                         /* Try again once, should only happen if (in_length%64 == 0) */
943                         result2 = jlink_usb_read_emu_result(jlink);
944                         if (1 != result2)
945                         {
946                                 LOG_ERROR("jlink_usb_read_emu_result failed "
947                                         "(requested = 1, result=%d)", result2);
948                                 return ERROR_JTAG_DEVICE_ERROR;
949                         }
950                 }
951
952                 /* Check the result itself */
953                 result2 = usb_emu_result_buffer[0];
954         }
955         else
956         {
957                 /* Save the result, then remove it from return value */
958                 result2 = usb_in_buffer[result--];
959         }
960
961         if (result2)
962         {
963                 LOG_ERROR("jlink_usb_message failed with result=%d)", result2);
964                 return ERROR_JTAG_DEVICE_ERROR;
965         }
966
967         return result;
968 }
969
970 /* calls the given usb_bulk_* function, allowing for the data to trickle in with some timeouts  */
971 static int usb_bulk_with_retries(
972                 int (*f)(usb_dev_handle *, int, char *, int, int),
973                 usb_dev_handle *dev, int ep,
974                 char *bytes, int size, int timeout)
975 {
976         int tries = 3, count = 0;
977
978         while (tries && (count < size))
979         {
980                 int result = f(dev, ep, bytes + count, size - count, timeout);
981                 if (result > 0)
982                         count += result;
983                 else if ((-ETIMEDOUT != result) || !--tries)
984                         return result;
985         }
986         return count;
987 }
988
989 static int wrap_usb_bulk_write(usb_dev_handle *dev, int ep,
990                                char *buff, int size, int timeout)
991 {
992         /* usb_bulk_write() takes const char *buff */
993         return usb_bulk_write(dev, ep, buff, size, timeout);
994 }
995
996 static inline int usb_bulk_write_ex(usb_dev_handle *dev, int ep,
997                 char *bytes, int size, int timeout)
998 {
999         return usb_bulk_with_retries(&wrap_usb_bulk_write,
1000                         dev, ep, bytes, size, timeout);
1001 }
1002
1003 static inline int usb_bulk_read_ex(usb_dev_handle *dev, int ep,
1004                 char *bytes, int size, int timeout)
1005 {
1006         return usb_bulk_with_retries(&usb_bulk_read,
1007                         dev, ep, bytes, size, timeout);
1008 }
1009
1010 /* Write data from out_buffer to USB. */
1011 static int jlink_usb_write(struct jlink *jlink, int out_length)
1012 {
1013         int result;
1014
1015         if (out_length > JLINK_OUT_BUFFER_SIZE)
1016         {
1017                 LOG_ERROR("jlink_write illegal out_length=%d (max=%d)", out_length, JLINK_OUT_BUFFER_SIZE);
1018                 return -1;
1019         }
1020
1021         result = usb_bulk_write_ex(jlink->usb_handle, jlink_write_ep,
1022                 (char *)usb_out_buffer, out_length, JLINK_USB_TIMEOUT);
1023
1024         DEBUG_JTAG_IO("jlink_usb_write, out_length = %d, result = %d", out_length, result);
1025
1026 #ifdef _DEBUG_USB_COMMS_
1027         jlink_debug_buffer(usb_out_buffer, out_length);
1028 #endif
1029         return result;
1030 }
1031
1032 /* Read data from USB into in_buffer. */
1033 static int jlink_usb_read(struct jlink *jlink, int expected_size)
1034 {
1035         int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
1036                 (char *)usb_in_buffer, expected_size, JLINK_USB_TIMEOUT);
1037
1038         DEBUG_JTAG_IO("jlink_usb_read, result = %d", result);
1039
1040 #ifdef _DEBUG_USB_COMMS_
1041         jlink_debug_buffer(usb_in_buffer, result);
1042 #endif
1043         return result;
1044 }
1045
1046 /* Read the result from the previous EMU cmd into result_buffer. */
1047 static int jlink_usb_read_emu_result(struct jlink *jlink)
1048 {
1049         int result = usb_bulk_read_ex(jlink->usb_handle, jlink_read_ep,
1050                 (char *)usb_emu_result_buffer, 1 /* JLINK_EMU_RESULT_BUFFER_SIZE */,
1051                 JLINK_USB_TIMEOUT);
1052
1053         DEBUG_JTAG_IO("jlink_usb_read_result, result = %d", result);
1054
1055 #ifdef _DEBUG_USB_COMMS_
1056         jlink_debug_buffer(usb_emu_result_buffer, result);
1057 #endif
1058         return result;
1059 }
1060
1061 #ifdef _DEBUG_USB_COMMS_
1062 #define BYTES_PER_LINE  16
1063
1064 static void jlink_debug_buffer(uint8_t *buffer, int length)
1065 {
1066         char line[81];
1067         char s[4];
1068         int i;
1069         int j;
1070
1071         for (i = 0; i < length; i += BYTES_PER_LINE)
1072         {
1073                 snprintf(line, 5, "%04x", i);
1074                 for (j = i; j < i + BYTES_PER_LINE && j < length; j++)
1075                 {
1076                         snprintf(s, 4, " %02x", buffer[j]);
1077                         strcat(line, s);
1078                 }
1079                 LOG_DEBUG("%s", line);
1080         }
1081 }
1082 #endif
1083