1 /***************************************************************************
2 * Copyright (C) 2006 by Magnus Lundin
5 * Copyright (C) 2008 by Spencer Oliver
8 * Copyright (C) 2009 by Oyvind Harboe
9 * oyvind.harboe@zylin.com
11 * Copyright (C) 2009-2010 by David Brownell
13 * This program is free software; you can redistribute it and/or modify
14 * it under the terms of the GNU General Public License as published by
15 * the Free Software Foundation; either version 2 of the License, or
16 * (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the
25 * Free Software Foundation, Inc.,
26 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
27 ***************************************************************************/
31 * This file implements JTAG transport support for cores implementing
32 the ARM Debug Interface version 5 (ADIv5).
40 #include "arm_adi_v5.h"
41 #include <helper/time_support.h>
43 /* JTAG instructions/registers for JTAG-DP and SWJ-DP */
44 #define JTAG_DP_ABORT 0x8
45 #define JTAG_DP_DPACC 0xA
46 #define JTAG_DP_APACC 0xB
47 #define JTAG_DP_IDCODE 0xE
49 /* three-bit ACK values for DPACC and APACC reads */
50 #define JTAG_ACK_OK_FAULT 0x2
51 #define JTAG_ACK_WAIT 0x1
53 static int jtag_ap_q_abort(struct adiv5_dap
*dap
, uint8_t *ack
);
55 /***************************************************************************
57 * DPACC and APACC scanchain access through JTAG-DP (or SWJ-DP)
59 ***************************************************************************/
62 * Scan DPACC or APACC using target ordered uint8_t buffers. No endianness
63 * conversions are performed. See section 4.4.3 of the ADIv5 spec, which
64 * discusses operations which access these registers.
66 * Note that only one scan is performed. If RnW is set, a separate scan
67 * will be needed to collect the data which was read; the "invalue" collects
68 * the posted result of a preceding operation, not the current one.
71 * @param instr JTAG_DP_APACC (AP access) or JTAG_DP_DPACC (DP access)
72 * @param reg_addr two significant bits; A[3:2]; for APACC access, the
73 * SELECT register has more addressing bits.
74 * @param RnW false iff outvalue will be written to the DP or AP
75 * @param outvalue points to a 32-bit (little-endian) integer
76 * @param invalue NULL, or points to a 32-bit (little-endian) integer
77 * @param ack points to where the three bit JTAG_ACK_* code will be stored
80 static int adi_jtag_dp_scan(struct adiv5_dap
*dap
,
81 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
82 uint8_t *outvalue
, uint8_t *invalue
, uint8_t *ack
)
84 struct arm_jtag
*jtag_info
= dap
->jtag_info
;
85 struct scan_field fields
[2];
89 retval
= arm_jtag_set_instr(jtag_info
, instr
, NULL
, TAP_IDLE
);
90 if (retval
!= ERROR_OK
)
93 /* Scan out a read or write operation using some DP or AP register.
94 * For APACC access with any sticky error flag set, this is discarded.
96 fields
[0].num_bits
= 3;
97 buf_set_u32(&out_addr_buf
, 0, 3, ((reg_addr
>> 1) & 0x6) | (RnW
& 0x1));
98 fields
[0].out_value
= &out_addr_buf
;
99 fields
[0].in_value
= ack
;
101 /* NOTE: if we receive JTAG_ACK_WAIT, the previous operation did not
102 * complete; data we write is discarded, data we read is unpredictable.
103 * When overrun detect is active, STICKYORUN is set.
106 fields
[1].num_bits
= 32;
107 fields
[1].out_value
= outvalue
;
108 fields
[1].in_value
= invalue
;
110 jtag_add_dr_scan(jtag_info
->tap
, 2, fields
, TAP_IDLE
);
112 /* Add specified number of tck clocks after starting memory bus
113 * access, giving the hardware time to complete the access.
114 * They provide more time for the (MEM) AP to complete the read ...
115 * See "Minimum Response Time" for JTAG-DP, in the ADIv5 spec.
117 if ((instr
== JTAG_DP_APACC
)
118 && ((reg_addr
== AP_REG_DRW
)
119 || ((reg_addr
& 0xF0) == AP_REG_BD0
))
120 && (dap
->memaccess_tck
!= 0))
121 jtag_add_runtest(dap
->memaccess_tck
,
128 * Scan DPACC or APACC out and in from host ordered uint32_t buffers.
129 * This is exactly like adi_jtag_dp_scan(), except that endianness
130 * conversions are performed (so the types of invalue and outvalue
131 * must be different).
133 static int adi_jtag_dp_scan_u32(struct adiv5_dap
*dap
,
134 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
135 uint32_t outvalue
, uint32_t *invalue
, uint8_t *ack
)
137 uint8_t out_value_buf
[4];
140 buf_set_u32(out_value_buf
, 0, 32, outvalue
);
142 retval
= adi_jtag_dp_scan(dap
, instr
, reg_addr
, RnW
,
143 out_value_buf
, (uint8_t *)invalue
, ack
);
144 if (retval
!= ERROR_OK
)
148 jtag_add_callback(arm_le_to_h_u32
,
149 (jtag_callback_data_t
) invalue
);
155 * Utility to write AP registers.
157 static inline int adi_jtag_ap_write_check(struct adiv5_dap
*dap
,
158 uint8_t reg_addr
, uint8_t *outvalue
)
160 return adi_jtag_dp_scan(dap
, JTAG_DP_APACC
, reg_addr
, DPAP_WRITE
,
161 outvalue
, NULL
, NULL
);
164 static int adi_jtag_scan_inout_check_u32(struct adiv5_dap
*dap
,
165 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
166 uint32_t outvalue
, uint32_t *invalue
)
170 /* Issue the read or write */
171 retval
= adi_jtag_dp_scan_u32(dap
, instr
, reg_addr
,
172 RnW
, outvalue
, NULL
, NULL
);
173 if (retval
!= ERROR_OK
)
176 /* For reads, collect posted value; RDBUFF has no other effect.
177 * Assumes read gets acked with OK/FAULT, and CTRL_STAT says "OK".
179 if ((RnW
== DPAP_READ
) && (invalue
!= NULL
))
180 retval
= adi_jtag_dp_scan_u32(dap
, JTAG_DP_DPACC
,
181 DP_RDBUFF
, DPAP_READ
, 0, invalue
, &dap
->ack
);
185 static int jtagdp_transaction_endcheck(struct adiv5_dap
*dap
)
190 /* too expensive to call keep_alive() here */
194 * It is easy to be in a JTAG clock range where the target
195 * is not operating in a stable fashion. This happens
198 * - the user may construct a simple test case to try to see
199 * if a higher JTAG clock works to eke out more performance.
200 * This simple case may pass, but more complex situations can
203 * - The mostly works JTAG clock rate and the complete failure
204 * JTAG clock rate may be as much as 2-4x apart. This seems
205 * to be especially true on RC oscillator driven parts.
207 * So: even if calling adi_jtag_scan_inout_check_u32() multiple
208 * times here seems to "make things better here", it is just
209 * hiding problems with too high a JTAG clock.
211 * Note that even if some parts have RCLK/RTCK, that doesn't
212 * mean that RCLK/RTCK is the *correct* rate to run the JTAG
213 * interface at, i.e. RCLK/RTCK rates can be "too high", especially
214 * before the RC oscillator phase is not yet complete.
217 /* Post CTRL/STAT read; discard any previous posted read value
218 * but collect its ACK status.
220 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
221 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
);
222 if (retval
!= ERROR_OK
)
224 retval
= jtag_execute_queue();
225 if (retval
!= ERROR_OK
)
228 dap
->ack
= dap
->ack
& 0x7;
230 /* common code path avoids calling timeval_ms() */
231 if (dap
->ack
!= JTAG_ACK_OK_FAULT
) {
232 long long then
= timeval_ms();
234 while (dap
->ack
!= JTAG_ACK_OK_FAULT
) {
235 if (dap
->ack
== JTAG_ACK_WAIT
) {
236 if ((timeval_ms()-then
) > 1000) {
237 LOG_WARNING("Timeout (1000ms) waiting "
239 "in JTAG-DP transaction - aborting");
242 int abort_ret
= jtag_ap_q_abort(dap
, &ack
);
245 LOG_WARNING("Abort failed : return=%d ack=%d", abort_ret
, ack
);
247 return ERROR_JTAG_DEVICE_ERROR
;
250 LOG_WARNING("Invalid ACK %#x "
251 "in JTAG-DP transaction",
253 return ERROR_JTAG_DEVICE_ERROR
;
256 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
257 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
);
258 if (retval
!= ERROR_OK
)
260 retval
= jtag_execute_queue();
261 if (retval
!= ERROR_OK
)
263 dap
->ack
= dap
->ack
& 0x7;
267 /* REVISIT also STICKYCMP, for pushed comparisons (nyet used) */
269 /* Check for STICKYERR and STICKYORUN */
270 if (ctrlstat
& (SSTICKYORUN
| SSTICKYERR
)) {
271 LOG_DEBUG("jtag-dp: CTRL/STAT error, 0x%" PRIx32
, ctrlstat
);
272 /* Check power to debug regions */
273 if ((ctrlstat
& 0xf0000000) != 0xf0000000) {
274 retval
= ahbap_debugport_init(dap
);
275 if (retval
!= ERROR_OK
)
278 uint32_t mem_ap_csw
, mem_ap_tar
;
280 /* Maybe print information about last intended
281 * MEM-AP access; but not if autoincrementing.
282 * *Real* CSW and TAR values are always shown.
284 if (dap
->ap_tar_value
!= (uint32_t) -1)
285 LOG_DEBUG("MEM-AP Cached values: "
287 ", ap_csw 0x%" PRIx32
288 ", ap_tar 0x%" PRIx32
,
293 if (ctrlstat
& SSTICKYORUN
)
294 LOG_ERROR("JTAG-DP OVERRUN - check clock, "
295 "memaccess, or reduce jtag speed");
297 if (ctrlstat
& SSTICKYERR
)
298 LOG_ERROR("JTAG-DP STICKY ERROR");
300 /* Clear Sticky Error Bits */
301 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
302 DP_CTRL_STAT
, DPAP_WRITE
,
303 dap
->dp_ctrl_stat
| SSTICKYORUN
305 if (retval
!= ERROR_OK
)
307 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
308 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
);
309 if (retval
!= ERROR_OK
)
311 retval
= jtag_execute_queue();
312 if (retval
!= ERROR_OK
)
315 LOG_DEBUG("jtag-dp: CTRL/STAT 0x%" PRIx32
, ctrlstat
);
317 retval
= dap_queue_ap_read(dap
,
318 AP_REG_CSW
, &mem_ap_csw
);
319 if (retval
!= ERROR_OK
)
322 retval
= dap_queue_ap_read(dap
,
323 AP_REG_TAR
, &mem_ap_tar
);
324 if (retval
!= ERROR_OK
)
327 retval
= jtag_execute_queue();
328 if (retval
!= ERROR_OK
)
330 LOG_ERROR("MEM_AP_CSW 0x%" PRIx32
", MEM_AP_TAR 0x%"
331 PRIx32
, mem_ap_csw
, mem_ap_tar
);
334 retval
= jtag_execute_queue();
335 if (retval
!= ERROR_OK
)
337 return ERROR_JTAG_DEVICE_ERROR
;
343 /*--------------------------------------------------------------------------*/
345 static int jtag_idcode_q_read(struct adiv5_dap
*dap
,
346 uint8_t *ack
, uint32_t *data
)
348 struct arm_jtag
*jtag_info
= dap
->jtag_info
;
350 struct scan_field fields
[1];
352 /* This is a standard JTAG operation -- no DAP tweakage */
353 retval
= arm_jtag_set_instr(jtag_info
, JTAG_DP_IDCODE
, NULL
, TAP_IDLE
);
354 if (retval
!= ERROR_OK
)
357 fields
[0].num_bits
= 32;
358 fields
[0].out_value
= NULL
;
359 fields
[0].in_value
= (void *) data
;
361 jtag_add_dr_scan(jtag_info
->tap
, 1, fields
, TAP_IDLE
);
363 jtag_add_callback(arm_le_to_h_u32
,
364 (jtag_callback_data_t
) data
);
369 static int jtag_dp_q_read(struct adiv5_dap
*dap
, unsigned reg
,
372 return adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
373 reg
, DPAP_READ
, 0, data
);
376 static int jtag_dp_q_write(struct adiv5_dap
*dap
, unsigned reg
,
379 return adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
380 reg
, DPAP_WRITE
, data
, NULL
);
383 /** Select the AP register bank matching bits 7:4 of reg. */
384 static int jtag_ap_q_bankselect(struct adiv5_dap
*dap
, unsigned reg
)
386 uint32_t select_ap_bank
= reg
& 0x000000F0;
388 if (select_ap_bank
== dap
->ap_bank_value
)
390 dap
->ap_bank_value
= select_ap_bank
;
392 select_ap_bank
|= dap
->ap_current
;
394 return jtag_dp_q_write(dap
, DP_SELECT
, select_ap_bank
);
397 static int jtag_ap_q_read(struct adiv5_dap
*dap
, unsigned reg
,
400 int retval
= jtag_ap_q_bankselect(dap
, reg
);
402 if (retval
!= ERROR_OK
)
405 return adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_APACC
, reg
,
409 static int jtag_ap_q_write(struct adiv5_dap
*dap
, unsigned reg
,
412 uint8_t out_value_buf
[4];
414 int retval
= jtag_ap_q_bankselect(dap
, reg
);
415 if (retval
!= ERROR_OK
)
418 buf_set_u32(out_value_buf
, 0, 32, data
);
420 return adi_jtag_ap_write_check(dap
, reg
, out_value_buf
);
423 static int jtag_ap_q_read_block(struct adiv5_dap
*dap
, unsigned reg
,
424 uint32_t blocksize
, uint8_t *buffer
)
427 int retval
= ERROR_OK
;
429 /* Scan out first read */
430 retval
= adi_jtag_dp_scan(dap
, JTAG_DP_APACC
, reg
,
431 DPAP_READ
, 0, NULL
, NULL
);
432 if (retval
!= ERROR_OK
)
435 for (readcount
= 0; readcount
< blocksize
- 1; readcount
++) {
436 /* Scan out next read; scan in posted value for the
437 * previous one. Assumes read is acked "OK/FAULT",
438 * and CTRL_STAT says that meant "OK".
440 retval
= adi_jtag_dp_scan(dap
, JTAG_DP_APACC
, reg
,
441 DPAP_READ
, 0, buffer
+ 4 * readcount
,
443 if (retval
!= ERROR_OK
)
447 /* Scan in last posted value; RDBUFF has no other effect,
448 * assuming ack is OK/FAULT and CTRL_STAT says "OK".
450 retval
= adi_jtag_dp_scan(dap
, JTAG_DP_DPACC
, DP_RDBUFF
,
451 DPAP_READ
, 0, buffer
+ 4 * readcount
,
457 static int jtag_ap_q_abort(struct adiv5_dap
*dap
, uint8_t *ack
)
459 /* for JTAG, this is the only valid ABORT register operation */
460 return adi_jtag_dp_scan_u32(dap
, JTAG_DP_ABORT
,
461 0, DPAP_WRITE
, 1, NULL
, ack
);
464 static int jtag_dp_run(struct adiv5_dap
*dap
)
466 return jtagdp_transaction_endcheck(dap
);
469 /* FIXME don't export ... just initialize as
472 const struct dap_ops jtag_dp_ops
= {
473 .queue_idcode_read
= jtag_idcode_q_read
,
474 .queue_dp_read
= jtag_dp_q_read
,
475 .queue_dp_write
= jtag_dp_q_write
,
476 .queue_ap_read
= jtag_ap_q_read
,
477 .queue_ap_write
= jtag_ap_q_write
,
478 .queue_ap_read_block
= jtag_ap_q_read_block
,
479 .queue_ap_abort
= jtag_ap_q_abort
,
484 static const uint8_t swd2jtag_bitseq
[] = {
485 /* More than 50 TCK/SWCLK cycles with TMS/SWDIO high,
486 * putting both JTAG and SWD logic into reset state.
488 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
489 /* Switching equence disables SWD and enables JTAG
490 * NOTE: bits in the DP's IDCODE can expose the need for
491 * the old/deprecated sequence (0xae 0xde).
494 /* At least 50 TCK/SWCLK cycles with TMS/SWDIO high,
495 * putting both JTAG and SWD logic into reset state.
496 * NOTE: some docs say "at least 5".
498 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
501 /** Put the debug link into JTAG mode, if the target supports it.
502 * The link's initial mode may be either SWD or JTAG.
504 * @param target Enters JTAG mode (if possible).
506 * Note that targets implemented with SW-DP do not support JTAG, and
507 * that some targets which could otherwise support it may have been
508 * configured to disable JTAG signaling
510 * @return ERROR_OK or else a fault code.
512 int dap_to_jtag(struct target
*target
)
516 LOG_DEBUG("Enter JTAG mode");
518 /* REVISIT it's nasty to need to make calls to a "jtag"
519 * subsystem if the link isn't in JTAG mode...
522 retval
= jtag_add_tms_seq(8 * sizeof(swd2jtag_bitseq
),
523 swd2jtag_bitseq
, TAP_RESET
);
524 if (retval
== ERROR_OK
)
525 retval
= jtag_execute_queue();
527 /* REVISIT set up the DAP's ops vector for JTAG mode. */