1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * Copyright (C) 2007,2008 Øyvind Harboe *
6 * oyvind.harboe@zylin.com *
8 * Copyright (C) 2009 Zachary T Welch *
9 * zw@superlucidity.net *
11 * This program is free software; you can redistribute it and/or modify *
12 * it under the terms of the GNU General Public License as published by *
13 * the Free Software Foundation; either version 2 of the License, or *
14 * (at your option) any later version. *
16 * This program is distributed in the hope that it will be useful, *
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
19 * GNU General Public License for more details. *
21 * You should have received a copy of the GNU General Public License *
22 * along with this program. If not, see <http://www.gnu.org/licenses/>. *
23 ***************************************************************************/
25 #ifndef OPENOCD_JTAG_INTERFACE_H
26 #define OPENOCD_JTAG_INTERFACE_H
28 #include <jtag/jtag.h>
29 #include <jtag/swim.h>
30 #include <target/arm_tpiu_swo.h>
33 * The "Cable Helper API" is what the cable drivers can use to help
34 * implement their "Cable API". So a Cable Helper API is a set of
35 * helper functions used by cable drivers, and this is different from a
36 * Cable API. A "Cable API" is what higher level code used to talk to a
41 /** implementation of wrapper function tap_set_state() */
42 void tap_set_state_impl(tap_state_t new_state
);
45 * This function sets the state of a "state follower" which tracks the
46 * state of the TAPs connected to the cable. The state follower is
47 * hopefully always in the same state as the actual TAPs in the jtag
48 * chain, and will be so if there are no bugs in the tracking logic
49 * within that cable driver.
51 * All the cable drivers call this function to indicate the state they
52 * think the TAPs attached to their cables are in. Because this
53 * function can also log transitions, it will be helpful to call this
54 * function with every transition that the TAPs being manipulated are
55 * expected to traverse, not just end points of a multi-step state path.
57 * @param new_state The state we think the TAPs are currently in (or
58 * are about to enter).
60 #define tap_set_state(new_state) \
62 LOG_DEBUG_IO("tap_set_state(%s)", tap_state_name(new_state)); \
63 tap_set_state_impl(new_state); \
67 * This function gets the state of the "state follower" which tracks the
68 * state of the TAPs connected to the cable. @see tap_set_state @return
69 * tap_state_t The state the TAPs are in now.
71 tap_state_t
tap_get_state(void);
74 * This function sets the state of an "end state follower" which tracks
75 * the state that any cable driver thinks will be the end (resultant)
76 * state of the current TAP SIR or SDR operation.
78 * At completion of that TAP operation this value is copied into the
79 * state follower via tap_set_state().
81 * @param new_end_state The state the TAPs should enter at completion of
82 * a pending TAP operation.
84 void tap_set_end_state(tap_state_t new_end_state
);
87 * For more information, @see tap_set_end_state
88 * @return tap_state_t - The state the TAPs should be in at completion of the current TAP operation.
90 tap_state_t
tap_get_end_state(void);
93 * This function provides a "bit sequence" indicating what has to be
94 * done with TMS during a sequence of seven TAP clock cycles in order to
95 * get from state \a "from" to state \a "to".
97 * The length of the sequence must be determined with a parallel call to
98 * tap_get_tms_path_len().
100 * @param from The starting state.
101 * @param to The desired final state.
102 * @return int The required TMS bit sequence, with the first bit in the
105 int tap_get_tms_path(tap_state_t from
, tap_state_t to
);
108 * Function int tap_get_tms_path_len
109 * returns the total number of bits that represents a TMS path
110 * transition as given by the function tap_get_tms_path().
112 * For at least one interface (JLink) it's not OK to simply "pad" TMS
113 * sequences to fit a whole byte. (I suspect this is a general TAP
114 * problem within OOCD.) Padding TMS causes all manner of instability
115 * that's not easily discovered. Using this routine we can apply
116 * EXACTLY the state transitions required to make something work - no
119 * @param from is the starting state
120 * @param to is the resultant or final state
121 * @return int - the total number of bits in a transition.
123 int tap_get_tms_path_len(tap_state_t from
, tap_state_t to
);
127 * Function tap_move_ndx
128 * when given a stable state, returns an index from 0-5. The index corresponds to a
129 * sequence of stable states which are given in this order: <p>
130 * { TAP_RESET, TAP_IDLE, TAP_DRSHIFT, TAP_DRPAUSE, TAP_IRSHIFT, TAP_IRPAUSE }
132 * This sequence corresponds to look up tables which are used in some of the
134 * @param astate is the stable state to find in the sequence. If a non stable
135 * state is passed, this may cause the program to output an error message
137 * @return int - the array (or sequence) index as described above
139 int tap_move_ndx(tap_state_t astate
);
142 * Function tap_is_state_stable
143 * returns true if the \a astate is stable.
145 bool tap_is_state_stable(tap_state_t astate
);
148 * Function tap_state_transition
149 * takes a current TAP state and returns the next state according to the tms value.
150 * @param current_state is the state of a TAP currently.
151 * @param tms is either zero or non-zero, just like a real TMS line in a jtag interface.
152 * @return tap_state_t - the next state a TAP would enter.
154 tap_state_t
tap_state_transition(tap_state_t current_state
, bool tms
);
156 /** Allow switching between old and new TMS tables. @see tap_get_tms_path */
157 void tap_use_new_tms_table(bool use_new
);
158 /** @returns True if new TMS table is active; false otherwise. */
159 bool tap_uses_new_tms_table(void);
163 * @brief Prints verbose TAP state transitions for the given TMS/TDI buffers.
164 * @param tms_buf must points to a buffer containing the TMS bitstream.
165 * @param tdi_buf must points to a buffer containing the TDI bitstream.
166 * @param tap_len must specify the length of the TMS/TDI bitstreams.
167 * @param start_tap_state must specify the current TAP state.
168 * @returns the final TAP state; pass as @a start_tap_state in following call.
170 static inline tap_state_t
jtag_debug_state_machine(const void *tms_buf
,
171 const void *tdi_buf
, unsigned tap_len
, tap_state_t start_tap_state
)
173 /* Private declaration */
174 tap_state_t
jtag_debug_state_machine_(const void *tms_buf
, const void *tdi_buf
,
175 unsigned tap_len
, tap_state_t start_tap_state
);
177 if (LOG_LEVEL_IS(LOG_LVL_DEBUG_IO
))
178 return jtag_debug_state_machine_(tms_buf
, tdi_buf
, tap_len
, start_tap_state
);
180 return start_tap_state
;
184 * Represents a driver for a debugging interface.
186 * @todo Rename; perhaps "debug_driver". This isn't an interface,
187 * it's a driver! Also, not all drivers support JTAG.
189 * @todo We need a per-instance structure too, and changes to pass
190 * that structure to the driver. Instances can for example be in
191 * either SWD or JTAG modes. This will help remove globals, and
192 * eventually to cope with systems which have more than one such
193 * debugging interface.
195 struct jtag_interface
{
197 * Bit vector listing capabilities exposed by this driver.
200 #define DEBUG_CAP_TMS_SEQ (1 << 0)
203 * Execute queued commands.
204 * @returns ERROR_OK on success, or an error code on failure.
206 int (*execute_queue
)(void);
210 * Represents a driver for a debugging interface
212 * @todo We need a per-instance structure too, and changes to pass
213 * that structure to the driver. Instances can for example be in
214 * either SWD or JTAG modes. This will help remove globals, and
215 * eventually to cope with systems which have more than one such
216 * debugging interface.
218 struct adapter_driver
{
219 /** The name of the interface driver. */
220 const char * const name
;
222 /** transports supported in C code (NULL terminated vector) */
223 const char * const *transports
;
226 * The interface driver may register additional commands to expose
227 * additional features not covered by the standard command set.
229 const struct command_registration
*commands
;
232 * Interface driver must initialize any resources and connect to a
235 * quit() is invoked if and only if init() succeeds. quit() is always
236 * invoked if init() succeeds. Same as malloc() + free(). Always
237 * invoke free() if malloc() succeeds and do not invoke free()
240 * @returns ERROR_OK on success, or an error code on failure.
245 * Interface driver must tear down all resources and disconnect from
248 * @returns ERROR_OK on success, or an error code on failure.
253 * Control (assert/deassert) the signals SRST and TRST on the interface.
254 * This function is synchronous and should be called after the adapter
255 * queue has been properly flushed.
256 * This function is optional.
257 * Adapters that don't support resets can either not define this function
258 * or return an error code.
259 * Adapters that don't support one of the two reset should ignore the
260 * request to assert the missing signal and eventually log an error.
262 * @param srst 1 to assert SRST, 0 to deassert SRST.
263 * @param trst 1 to assert TRST, 0 to deassert TRST.
264 * @returns ERROR_OK on success, or an error code on failure.
266 int (*reset
)(int srst
, int trst
);
269 * Set the interface speed.
270 * @param speed The new interface speed setting.
271 * @returns ERROR_OK on success, or an error code on failure.
273 int (*speed
)(int speed
);
276 * Returns JTAG maximum speed for KHz. 0 = RTCK. The function returns
277 * a failure if it can't support the KHz/RTCK.
279 * WARNING!!!! if RTCK is *slow* then think carefully about
280 * whether you actually want to support this in the driver.
281 * Many target scripts are written to handle the absence of RTCK
282 * and use a fallback kHz TCK.
283 * @returns ERROR_OK on success, or an error code on failure.
285 int (*khz
)(int khz
, int *jtag_speed
);
288 * Calculate the clock frequency (in KHz) for the given @a speed.
289 * @param speed The desired interface speed setting.
290 * @param khz On return, contains the speed in KHz (0 for RTCK).
291 * @returns ERROR_OK on success, or an error code if the
292 * interface cannot support the specified speed (KHz or RTCK).
294 int (*speed_div
)(int speed
, int *khz
);
297 * Read and clear the power dropout flag. Note that a power dropout
298 * can be transitionary, easily much less than a ms.
300 * To find out if the power is *currently* on, one must invoke this
301 * method twice. Once to clear the power dropout flag and a second
302 * time to read the current state. The default implementation
303 * never reports power dropouts.
305 * @returns ERROR_OK on success, or an error code on failure.
307 int (*power_dropout
)(int *power_dropout
);
310 * Read and clear the srst asserted detection flag.
312 * Like power_dropout this does *not* read the current
313 * state. SRST assertion is transitionary and may be much
314 * less than 1ms, so the interface driver must watch for these
315 * events until this routine is called.
317 * @param srst_asserted On return, indicates whether SRST has
319 * @returns ERROR_OK on success, or an error code on failure.
321 int (*srst_asserted
)(int *srst_asserted
);
324 * Configure trace parameters for the adapter
326 * @param enabled Whether to enable trace
327 * @param pin_protocol Configured pin protocol
328 * @param port_size Trace port width for sync mode
329 * @param trace_freq A pointer to the configured trace
330 * frequency; if it points to 0, the adapter driver must write
331 * its maximum supported rate there
332 * @param traceclkin_freq TRACECLKIN frequency provided to the TPIU in Hz
333 * @param prescaler Pointer to the SWO prescaler calculated by the
335 * @returns ERROR_OK on success, an error code on failure.
337 int (*config_trace
)(bool enabled
, enum tpiu_pin_protocol pin_protocol
,
338 uint32_t port_size
, unsigned int *trace_freq
,
339 unsigned int traceclkin_freq
, uint16_t *prescaler
);
342 * Poll for new trace data
344 * @param buf A pointer to buffer to store received data
345 * @param size A pointer to buffer size; must be filled with
346 * the actual amount of bytes written
348 * @returns ERROR_OK on success, an error code on failure.
350 int (*poll_trace
)(uint8_t *buf
, size_t *size
);
352 /** Low-level JTAG APIs */
353 struct jtag_interface
*jtag_ops
;
355 /** Low-level SWD APIs */
356 const struct swd_driver
*swd_ops
;
358 /* DAP APIs over JTAG transport */
359 const struct dap_ops
*dap_jtag_ops
;
361 /* DAP APIs over SWD transport */
362 const struct dap_ops
*dap_swd_ops
;
365 const struct swim_driver
*swim_ops
;
368 extern const char * const jtag_only
[];
370 int adapter_resets(int assert_trst
, int assert_srst
);
371 int adapter_assert_reset(void);
372 int adapter_deassert_reset(void);
373 int adapter_config_trace(bool enabled
, enum tpiu_pin_protocol pin_protocol
,
374 uint32_t port_size
, unsigned int *trace_freq
,
375 unsigned int traceclkin_freq
, uint16_t *prescaler
);
376 int adapter_poll_trace(uint8_t *buf
, size_t *size
);
378 #endif /* OPENOCD_JTAG_INTERFACE_H */