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, write to the *
23 * Free Software Foundation, Inc., *
24 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *
25 ***************************************************************************/
27 #ifndef OPENOCD_JTAG_INTERFACE_H
28 #define OPENOCD_JTAG_INTERFACE_H
30 #include <jtag/jtag.h>
31 #include <target/armv7m_trace.h>
34 * The "Cable Helper API" is what the cable drivers can use to help
35 * implement their "Cable API". So a Cable Helper API is a set of
36 * helper functions used by cable drivers, and this is different from a
37 * Cable API. A "Cable API" is what higher level code used to talk to a
42 /** implementation of wrapper function tap_set_state() */
43 void tap_set_state_impl(tap_state_t new_state);
46 * This function sets the state of a "state follower" which tracks the
47 * state of the TAPs connected to the cable. The state follower is
48 * hopefully always in the same state as the actual TAPs in the jtag
49 * chain, and will be so if there are no bugs in the tracking logic
50 * within that cable driver.
52 * All the cable drivers call this function to indicate the state they
53 * think the TAPs attached to their cables are in. Because this
54 * function can also log transitions, it will be helpful to call this
55 * function with every transition that the TAPs being manipulated are
56 * expected to traverse, not just end points of a multi-step state path.
58 * @param new_state The state we think the TAPs are currently in (or
59 * are about to enter).
61 #if defined(_DEBUG_JTAG_IO_)
62 #define tap_set_state(new_state) \
64 LOG_DEBUG("tap_set_state(%s)", tap_state_name(new_state)); \
65 tap_set_state_impl(new_state); \
68 static inline void tap_set_state(tap_state_t new_state)
70 tap_set_state_impl(new_state);
75 * This function gets the state of the "state follower" which tracks the
76 * state of the TAPs connected to the cable. @see tap_set_state @return
77 * tap_state_t The state the TAPs are in now.
79 tap_state_t tap_get_state(void);
82 * This function sets the state of an "end state follower" which tracks
83 * the state that any cable driver thinks will be the end (resultant)
84 * state of the current TAP SIR or SDR operation.
86 * At completion of that TAP operation this value is copied into the
87 * state follower via tap_set_state().
89 * @param new_end_state The state the TAPs should enter at completion of
90 * a pending TAP operation.
92 void tap_set_end_state(tap_state_t new_end_state);
95 * For more information, @see tap_set_end_state
96 * @return tap_state_t - The state the TAPs should be in at completion of the current TAP operation.
98 tap_state_t tap_get_end_state(void);
101 * This function provides a "bit sequence" indicating what has to be
102 * done with TMS during a sequence of seven TAP clock cycles in order to
103 * get from state \a "from" to state \a "to".
105 * The length of the sequence must be determined with a parallel call to
106 * tap_get_tms_path_len().
108 * @param from The starting state.
109 * @param to The desired final state.
110 * @return int The required TMS bit sequence, with the first bit in the
113 int tap_get_tms_path(tap_state_t from, tap_state_t to);
116 * Function int tap_get_tms_path_len
117 * returns the total number of bits that represents a TMS path
118 * transition as given by the function tap_get_tms_path().
120 * For at least one interface (JLink) it's not OK to simply "pad" TMS
121 * sequences to fit a whole byte. (I suspect this is a general TAP
122 * problem within OOCD.) Padding TMS causes all manner of instability
123 * that's not easily discovered. Using this routine we can apply
124 * EXACTLY the state transitions required to make something work - no
127 * @param from is the starting state
128 * @param to is the resultant or final state
129 * @return int - the total number of bits in a transition.
131 int tap_get_tms_path_len(tap_state_t from, tap_state_t to);
135 * Function tap_move_ndx
136 * when given a stable state, returns an index from 0-5. The index corresponds to a
137 * sequence of stable states which are given in this order: <p>
138 * { TAP_RESET, TAP_IDLE, TAP_DRSHIFT, TAP_DRPAUSE, TAP_IRSHIFT, TAP_IRPAUSE }
140 * This sequence corresponds to look up tables which are used in some of the
142 * @param astate is the stable state to find in the sequence. If a non stable
143 * state is passed, this may cause the program to output an error message
145 * @return int - the array (or sequence) index as described above
147 int tap_move_ndx(tap_state_t astate);
150 * Function tap_is_state_stable
151 * returns true if the \a astate is stable.
153 bool tap_is_state_stable(tap_state_t astate);
156 * Function tap_state_transition
157 * takes a current TAP state and returns the next state according to the tms value.
158 * @param current_state is the state of a TAP currently.
159 * @param tms is either zero or non-zero, just like a real TMS line in a jtag interface.
160 * @return tap_state_t - the next state a TAP would enter.
162 tap_state_t tap_state_transition(tap_state_t current_state, bool tms);
164 /** Allow switching between old and new TMS tables. @see tap_get_tms_path */
165 void tap_use_new_tms_table(bool use_new);
166 /** @returns True if new TMS table is active; false otherwise. */
167 bool tap_uses_new_tms_table(void);
169 #ifdef _DEBUG_JTAG_IO_
171 * @brief Prints verbose TAP state transitions for the given TMS/TDI buffers.
172 * @param tms_buf must points to a buffer containing the TMS bitstream.
173 * @param tdi_buf must points to a buffer containing the TDI bitstream.
174 * @param tap_len must specify the length of the TMS/TDI bitstreams.
175 * @param start_tap_state must specify the current TAP state.
176 * @returns the final TAP state; pass as @a start_tap_state in following call.
178 tap_state_t jtag_debug_state_machine(const void *tms_buf, const void *tdi_buf,
179 unsigned tap_len, tap_state_t start_tap_state);
181 static inline tap_state_t jtag_debug_state_machine(const void *tms_buf,
182 const void *tdi_buf, unsigned tap_len, tap_state_t start_tap_state)
184 return start_tap_state;
186 #endif /* _DEBUG_JTAG_IO_ */
189 * Represents a driver for a debugging interface.
191 * @todo Rename; perhaps "debug_driver". This isn't an interface,
192 * it's a driver! Also, not all drivers support JTAG.
194 * @todo We need a per-instance structure too, and changes to pass
195 * that structure to the driver. Instances can for example be in
196 * either SWD or JTAG modes. This will help remove globals, and
197 * eventually to cope with systems which have more than one such
198 * debugging interface.
200 struct jtag_interface {
201 /** The name of the JTAG interface driver. */
202 const char * const name;
205 * Bit vector listing capabilities exposed by this driver.
208 #define DEBUG_CAP_TMS_SEQ (1 << 0)
210 /** transports supported in C code (NULL terminated vector) */
211 const char * const *transports;
213 const struct swd_driver *swd;
216 * Execute queued commands.
217 * @returns ERROR_OK on success, or an error code on failure.
219 int (*execute_queue)(void);
222 * Set the interface speed.
223 * @param speed The new interface speed setting.
224 * @returns ERROR_OK on success, or an error code on failure.
226 int (*speed)(int speed);
229 * The interface driver may register additional commands to expose
230 * additional features not covered by the standard command set.
232 const struct command_registration *commands;
235 * Interface driver must initialize any resources and connect to a
238 * quit() is invoked if and only if init() succeeds. quit() is always
239 * invoked if init() succeeds. Same as malloc() + free(). Always
240 * invoke free() if malloc() succeeds and do not invoke free()
243 * @returns ERROR_OK on success, or an error code on failure.
248 * Interface driver must tear down all resources and disconnect from
251 * @returns ERROR_OK on success, or an error code on failure.
256 * Returns JTAG maxium speed for KHz. 0 = RTCK. The function returns
257 * a failure if it can't support the KHz/RTCK.
259 * WARNING!!!! if RTCK is *slow* then think carefully about
260 * whether you actually want to support this in the driver.
261 * Many target scripts are written to handle the absence of RTCK
262 * and use a fallback kHz TCK.
263 * @returns ERROR_OK on success, or an error code on failure.
265 int (*khz)(int khz, int *jtag_speed);
268 * Calculate the clock frequency (in KHz) for the given @a speed.
269 * @param speed The desired interface speed setting.
270 * @param khz On return, contains the speed in KHz (0 for RTCK).
271 * @returns ERROR_OK on success, or an error code if the
272 * interface cannot support the specified speed (KHz or RTCK).
274 int (*speed_div)(int speed, int *khz);
277 * Read and clear the power dropout flag. Note that a power dropout
278 * can be transitionary, easily much less than a ms.
280 * To find out if the power is *currently* on, one must invoke this
281 * method twice. Once to clear the power dropout flag and a second
282 * time to read the current state. The default implementation
283 * never reports power dropouts.
285 * @returns ERROR_OK on success, or an error code on failure.
287 int (*power_dropout)(int *power_dropout);
290 * Read and clear the srst asserted detection flag.
292 * Like power_dropout this does *not* read the current
293 * state. SRST assertion is transitionary and may be much
294 * less than 1ms, so the interface driver must watch for these
295 * events until this routine is called.
297 * @param srst_asserted On return, indicates whether SRST has
299 * @returns ERROR_OK on success, or an error code on failure.
301 int (*srst_asserted)(int *srst_asserted);
304 * Configure trace parameters for the adapter
306 * @param enabled Whether to enable trace
307 * @param pin_protocol Configured pin protocol
308 * @param port_size Trace port width for sync mode
309 * @param trace_freq A pointer to the configured trace
310 * frequency; if it points to 0, the adapter driver must write
311 * its maximum supported rate there
312 * @returns ERROR_OK on success, an error code on failure.
314 int (*config_trace)(bool enabled, enum tpio_pin_protocol pin_protocol,
315 uint32_t port_size, unsigned int *trace_freq);
318 * Poll for new trace data
320 * @param buf A pointer to buffer to store received data
321 * @param size A pointer to buffer size; must be filled with
322 * the actual amount of bytes written
324 * @returns ERROR_OK on success, an error code on failure.
326 int (*poll_trace)(uint8_t *buf, size_t *size);
329 extern const char * const jtag_only[];
331 void adapter_assert_reset(void);
332 void adapter_deassert_reset(void);
333 int adapter_config_trace(bool enabled, enum tpio_pin_protocol pin_protocol,
334 uint32_t port_size, unsigned int *trace_freq);
335 int adapter_poll_trace(uint8_t *buf, size_t *size);
337 #endif /* OPENOCD_JTAG_INTERFACE_H */