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 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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
78 * @param memaccess_tck number of idle cycles to add after AP access
81 static int adi_jtag_dp_scan(struct adiv5_dap
*dap
,
82 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
83 uint8_t *outvalue
, uint8_t *invalue
, uint8_t *ack
,
84 uint32_t memaccess_tck
)
86 struct jtag_tap
*tap
= dap
->tap
;
87 struct scan_field fields
[2];
91 retval
= arm_jtag_set_instr(tap
, instr
, NULL
, TAP_IDLE
);
92 if (retval
!= ERROR_OK
)
95 /* Scan out a read or write operation using some DP or AP register.
96 * For APACC access with any sticky error flag set, this is discarded.
98 fields
[0].num_bits
= 3;
99 buf_set_u32(&out_addr_buf
, 0, 3, ((reg_addr
>> 1) & 0x6) | (RnW
& 0x1));
100 fields
[0].out_value
= &out_addr_buf
;
101 fields
[0].in_value
= ack
;
103 /* NOTE: if we receive JTAG_ACK_WAIT, the previous operation did not
104 * complete; data we write is discarded, data we read is unpredictable.
105 * When overrun detect is active, STICKYORUN is set.
108 fields
[1].num_bits
= 32;
109 fields
[1].out_value
= outvalue
;
110 fields
[1].in_value
= invalue
;
112 jtag_add_dr_scan(tap
, 2, fields
, TAP_IDLE
);
114 /* Add specified number of tck clocks after starting memory bus
115 * access, giving the hardware time to complete the access.
116 * They provide more time for the (MEM) AP to complete the read ...
117 * See "Minimum Response Time" for JTAG-DP, in the ADIv5 spec.
119 if ((instr
== JTAG_DP_APACC
)
120 && ((reg_addr
== MEM_AP_REG_DRW
)
121 || ((reg_addr
& 0xF0) == MEM_AP_REG_BD0
))
122 && memaccess_tck
!= 0)
123 jtag_add_runtest(memaccess_tck
, TAP_IDLE
);
129 * Scan DPACC or APACC out and in from host ordered uint32_t buffers.
130 * This is exactly like adi_jtag_dp_scan(), except that endianness
131 * conversions are performed (so the types of invalue and outvalue
132 * must be different).
134 static int adi_jtag_dp_scan_u32(struct adiv5_dap
*dap
,
135 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
136 uint32_t outvalue
, uint32_t *invalue
, uint8_t *ack
,
137 uint32_t memaccess_tck
)
139 uint8_t out_value_buf
[4];
142 buf_set_u32(out_value_buf
, 0, 32, outvalue
);
144 retval
= adi_jtag_dp_scan(dap
, instr
, reg_addr
, RnW
,
145 out_value_buf
, (uint8_t *)invalue
, ack
, memaccess_tck
);
146 if (retval
!= ERROR_OK
)
150 jtag_add_callback(arm_le_to_h_u32
,
151 (jtag_callback_data_t
) invalue
);
156 static void adi_jtag_finish_read(struct adiv5_dap
*dap
)
158 if (dap
->last_read
!= NULL
) {
159 adi_jtag_dp_scan_u32(dap
, JTAG_DP_DPACC
,
160 DP_RDBUFF
, DPAP_READ
, 0, dap
->last_read
, &dap
->ack
, 0);
161 dap
->last_read
= NULL
;
165 static int adi_jtag_scan_inout_check_u32(struct adiv5_dap
*dap
,
166 uint8_t instr
, uint8_t reg_addr
, uint8_t RnW
,
167 uint32_t outvalue
, uint32_t *invalue
, uint32_t memaccess_tck
)
171 /* Issue the read or write */
172 retval
= adi_jtag_dp_scan_u32(dap
, instr
, reg_addr
,
173 RnW
, outvalue
, NULL
, NULL
, memaccess_tck
);
174 if (retval
!= ERROR_OK
)
177 /* For reads, collect posted value; RDBUFF has no other effect.
178 * Assumes read gets acked with OK/FAULT, and CTRL_STAT says "OK".
180 if ((RnW
== DPAP_READ
) && (invalue
!= NULL
))
181 retval
= adi_jtag_dp_scan_u32(dap
, JTAG_DP_DPACC
,
182 DP_RDBUFF
, DPAP_READ
, 0, invalue
, &dap
->ack
, 0);
186 static int jtagdp_transaction_endcheck(struct adiv5_dap
*dap
)
191 /* too expensive to call keep_alive() here */
195 * It is easy to be in a JTAG clock range where the target
196 * is not operating in a stable fashion. This happens
199 * - the user may construct a simple test case to try to see
200 * if a higher JTAG clock works to eke out more performance.
201 * This simple case may pass, but more complex situations can
204 * - The mostly works JTAG clock rate and the complete failure
205 * JTAG clock rate may be as much as 2-4x apart. This seems
206 * to be especially true on RC oscillator driven parts.
208 * So: even if calling adi_jtag_scan_inout_check_u32() multiple
209 * times here seems to "make things better here", it is just
210 * hiding problems with too high a JTAG clock.
212 * Note that even if some parts have RCLK/RTCK, that doesn't
213 * mean that RCLK/RTCK is the *correct* rate to run the JTAG
214 * interface at, i.e. RCLK/RTCK rates can be "too high", especially
215 * before the RC oscillator phase is not yet complete.
218 /* Post CTRL/STAT read; discard any previous posted read value
219 * but collect its ACK status.
221 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
222 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
, 0);
223 if (retval
!= ERROR_OK
)
225 retval
= jtag_execute_queue();
226 if (retval
!= ERROR_OK
)
229 dap
->ack
= dap
->ack
& 0x7;
231 /* common code path avoids calling timeval_ms() */
232 if (dap
->ack
!= JTAG_ACK_OK_FAULT
) {
233 long long then
= timeval_ms();
235 while (dap
->ack
!= JTAG_ACK_OK_FAULT
) {
236 if (dap
->ack
== JTAG_ACK_WAIT
) {
237 if ((timeval_ms()-then
) > 1000) {
238 LOG_WARNING("Timeout (1000ms) waiting "
240 "in JTAG-DP transaction - aborting");
243 int abort_ret
= jtag_ap_q_abort(dap
, &ack
);
246 LOG_WARNING("Abort failed : return=%d ack=%d", abort_ret
, ack
);
248 return ERROR_JTAG_DEVICE_ERROR
;
251 LOG_WARNING("Invalid ACK %#x "
252 "in JTAG-DP transaction",
254 return ERROR_JTAG_DEVICE_ERROR
;
257 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
258 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
, 0);
259 if (retval
!= ERROR_OK
)
261 retval
= jtag_execute_queue();
262 if (retval
!= ERROR_OK
)
264 dap
->ack
= dap
->ack
& 0x7;
268 /* REVISIT also STICKYCMP, for pushed comparisons (nyet used) */
270 /* Check for STICKYERR and STICKYORUN */
271 if (ctrlstat
& (SSTICKYORUN
| SSTICKYERR
)) {
272 LOG_DEBUG("jtag-dp: CTRL/STAT error, 0x%" PRIx32
, ctrlstat
);
273 /* Check power to debug regions */
274 if ((ctrlstat
& (CDBGPWRUPREQ
| CDBGPWRUPACK
| CSYSPWRUPREQ
| CSYSPWRUPACK
)) !=
275 (CDBGPWRUPREQ
| CDBGPWRUPACK
| CSYSPWRUPREQ
| CSYSPWRUPACK
)) {
276 LOG_ERROR("Debug regions are unpowered, an unexpected reset might have happened");
277 return ERROR_JTAG_DEVICE_ERROR
;
279 if (ctrlstat
& SSTICKYORUN
)
280 LOG_ERROR("JTAG-DP OVERRUN - check clock, "
281 "memaccess, or reduce jtag speed");
283 if (ctrlstat
& SSTICKYERR
)
284 LOG_ERROR("JTAG-DP STICKY ERROR");
286 /* Clear Sticky Error Bits */
287 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
288 DP_CTRL_STAT
, DPAP_WRITE
,
289 dap
->dp_ctrl_stat
| SSTICKYORUN
290 | SSTICKYERR
, NULL
, 0);
291 if (retval
!= ERROR_OK
)
293 retval
= adi_jtag_scan_inout_check_u32(dap
, JTAG_DP_DPACC
,
294 DP_CTRL_STAT
, DPAP_READ
, 0, &ctrlstat
, 0);
295 if (retval
!= ERROR_OK
)
297 retval
= jtag_execute_queue();
298 if (retval
!= ERROR_OK
)
301 LOG_DEBUG("jtag-dp: CTRL/STAT 0x%" PRIx32
, ctrlstat
);
303 retval
= jtag_execute_queue();
304 if (retval
!= ERROR_OK
)
306 return ERROR_JTAG_DEVICE_ERROR
;
312 /*--------------------------------------------------------------------------*/
314 static int jtag_dp_q_read(struct adiv5_dap
*dap
, unsigned reg
,
317 int retval
= adi_jtag_dp_scan_u32(dap
, JTAG_DP_DPACC
, reg
,
318 DPAP_READ
, 0, dap
->last_read
, &dap
->ack
, 0);
319 dap
->last_read
= data
;
323 static int jtag_dp_q_write(struct adiv5_dap
*dap
, unsigned reg
,
326 int retval
= adi_jtag_dp_scan_u32(dap
, JTAG_DP_DPACC
,
327 reg
, DPAP_WRITE
, data
, dap
->last_read
, &dap
->ack
, 0);
328 dap
->last_read
= NULL
;
332 /** Select the AP register bank matching bits 7:4 of reg. */
333 static int jtag_ap_q_bankselect(struct adiv5_ap
*ap
, unsigned reg
)
335 struct adiv5_dap
*dap
= ap
->dap
;
336 uint32_t sel
= ((uint32_t)ap
->ap_num
<< 24) | (reg
& 0x000000F0);
338 if (sel
== dap
->select
)
343 return jtag_dp_q_write(dap
, DP_SELECT
, sel
);
346 static int jtag_ap_q_read(struct adiv5_ap
*ap
, unsigned reg
,
349 int retval
= jtag_ap_q_bankselect(ap
, reg
);
350 if (retval
!= ERROR_OK
)
353 retval
= adi_jtag_dp_scan_u32(ap
->dap
, JTAG_DP_APACC
, reg
,
354 DPAP_READ
, 0, ap
->dap
->last_read
, &ap
->dap
->ack
,
356 ap
->dap
->last_read
= data
;
361 static int jtag_ap_q_write(struct adiv5_ap
*ap
, unsigned reg
,
364 int retval
= jtag_ap_q_bankselect(ap
, reg
);
365 if (retval
!= ERROR_OK
)
368 retval
= adi_jtag_dp_scan_u32(ap
->dap
, JTAG_DP_APACC
, reg
,
369 DPAP_WRITE
, data
, ap
->dap
->last_read
, &ap
->dap
->ack
,
371 ap
->dap
->last_read
= NULL
;
375 static int jtag_ap_q_abort(struct adiv5_dap
*dap
, uint8_t *ack
)
377 /* for JTAG, this is the only valid ABORT register operation */
378 return adi_jtag_dp_scan_u32(dap
, JTAG_DP_ABORT
,
379 0, DPAP_WRITE
, 1, NULL
, ack
, 0);
382 static int jtag_dp_run(struct adiv5_dap
*dap
)
384 adi_jtag_finish_read(dap
);
385 return jtagdp_transaction_endcheck(dap
);
388 /* FIXME don't export ... just initialize as
391 const struct dap_ops jtag_dp_ops
= {
392 .queue_dp_read
= jtag_dp_q_read
,
393 .queue_dp_write
= jtag_dp_q_write
,
394 .queue_ap_read
= jtag_ap_q_read
,
395 .queue_ap_write
= jtag_ap_q_write
,
396 .queue_ap_abort
= jtag_ap_q_abort
,
401 static const uint8_t swd2jtag_bitseq
[] = {
402 /* More than 50 TCK/SWCLK cycles with TMS/SWDIO high,
403 * putting both JTAG and SWD logic into reset state.
405 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
406 /* Switching equence disables SWD and enables JTAG
407 * NOTE: bits in the DP's IDCODE can expose the need for
408 * the old/deprecated sequence (0xae 0xde).
411 /* At least 50 TCK/SWCLK cycles with TMS/SWDIO high,
412 * putting both JTAG and SWD logic into reset state.
413 * NOTE: some docs say "at least 5".
415 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
418 /** Put the debug link into JTAG mode, if the target supports it.
419 * The link's initial mode may be either SWD or JTAG.
421 * @param target Enters JTAG mode (if possible).
423 * Note that targets implemented with SW-DP do not support JTAG, and
424 * that some targets which could otherwise support it may have been
425 * configured to disable JTAG signaling
427 * @return ERROR_OK or else a fault code.
429 int dap_to_jtag(struct target
*target
)
433 LOG_DEBUG("Enter JTAG mode");
435 /* REVISIT it's nasty to need to make calls to a "jtag"
436 * subsystem if the link isn't in JTAG mode...
439 retval
= jtag_add_tms_seq(8 * sizeof(swd2jtag_bitseq
),
440 swd2jtag_bitseq
, TAP_RESET
);
441 if (retval
== ERROR_OK
)
442 retval
= jtag_execute_queue();
444 /* REVISIT set up the DAP's ops vector for JTAG mode. */