1 /***************************************************************************
2 * Copyright (C) 2005 by Dominic Rath *
3 * Dominic.Rath@gmx.de *
5 * This program is free software; you can redistribute it and/or modify *
6 * it under the terms of the GNU General Public License as published by *
7 * the Free Software Foundation; either version 2 of the License, or *
8 * (at your option) any later version. *
10 * This program is distributed in the hope that it will be useful, *
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
13 * GNU General Public License for more details. *
15 * You should have received a copy of the GNU General Public License *
16 * along with this program; if not, write to the *
17 * Free Software Foundation, Inc., *
18 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
19 ***************************************************************************/
26 /* project specific includes */
30 #include "configuration.h"
40 bitbang_interface_t *bitbang_interface;
42 int bitbang_execute_queue(void);
44 /* The bitbang driver leaves the TCK 0 when in idle */
47 void bitbang_end_state(enum tap_state state)
49 if (tap_move_map[state] != -1)
53 ERROR("BUG: %i is not a valid end state", state);
58 void bitbang_state_move(void) {
61 u8 tms_scan = TAP_MOVE(cur_state, end_state);
63 for (i = 0; i < 7; i++)
65 tms = (tms_scan >> i) & 1;
66 bitbang_interface->write(0, tms, 0);
67 bitbang_interface->write(1, tms, 0);
69 bitbang_interface->write(0, tms, 0);
71 cur_state = end_state;
74 void bitbang_path_move(pathmove_command_t *cmd)
76 int num_states = cmd->num_states;
83 if (tap_transitions[cur_state].low == cmd->path[state_count])
87 else if (tap_transitions[cur_state].high == cmd->path[state_count])
93 ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_strings[cur_state], tap_state_strings[cmd->path[state_count]]);
97 bitbang_interface->write(0, tms, 0);
98 bitbang_interface->write(1, tms, 0);
100 cur_state = cmd->path[state_count];
105 bitbang_interface->write(0, tms, 0);
107 end_state = cur_state;
110 void bitbang_runtest(int num_cycles)
114 enum tap_state saved_end_state = end_state;
116 /* only do a state_move when we're not already in RTI */
117 if (cur_state != TAP_RTI)
119 bitbang_end_state(TAP_RTI);
120 bitbang_state_move();
123 /* execute num_cycles */
124 bitbang_interface->write(0, 0, 0);
125 for (i = 0; i < num_cycles; i++)
127 bitbang_interface->write(1, 0, 0);
128 bitbang_interface->write(0, 0, 0);
131 /* finish in end_state */
132 bitbang_end_state(saved_end_state);
133 if (cur_state != end_state)
134 bitbang_state_move();
137 void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size)
139 enum tap_state saved_end_state = end_state;
141 int last_bit, last_bit_in;
143 if (!((!ir_scan && (cur_state == TAP_SD)) || (ir_scan && (cur_state == TAP_SI))))
146 bitbang_end_state(TAP_SI);
148 bitbang_end_state(TAP_SD);
150 bitbang_state_move();
151 bitbang_end_state(saved_end_state);
154 for (bit_cnt = 0; bit_cnt < scan_size - 1; bit_cnt++)
156 /* if we're just reading the scan, but don't care about the output
157 * default to outputting 'low', this also makes valgrind traces more readable,
158 * as it removes the dependency on an uninitialised value
160 if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1))
162 bitbang_interface->write(0, 0, 1);
163 bitbang_interface->write(1, 0, 1);
165 bitbang_interface->write(0, 0, 0);
166 bitbang_interface->write(1, 0, 0);
169 if (type != SCAN_OUT)
171 if (bitbang_interface->read())
172 buffer[(bit_cnt)/8] |= 1 << ((bit_cnt) % 8);
174 buffer[(bit_cnt)/8] &= ~(1 << ((bit_cnt) % 8));
178 if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1))
183 if ((ir_scan && (end_state == TAP_SI)) ||
184 (!ir_scan && (end_state == TAP_SD)))
186 bitbang_interface->write(0, 0, last_bit);
187 bitbang_interface->write(1, 0, last_bit);
189 if (type != SCAN_OUT)
190 last_bit_in = bitbang_interface->read();
192 bitbang_interface->write(0, 0, last_bit);
196 /* Shift-[ID]R -> Exit1-[ID]R */
197 bitbang_interface->write(0, 1, last_bit);
198 bitbang_interface->write(1, 1, last_bit);
200 if (type != SCAN_OUT)
201 last_bit_in = bitbang_interface->read();
203 /* Exit1-[ID]R -> Pause-[ID]R */
204 bitbang_interface->write(0, 0, 0);
205 bitbang_interface->write(1, 0, 0);
207 if (cur_state == TAP_SI)
212 if (cur_state != end_state)
213 bitbang_state_move();
215 bitbang_interface->write(0, 0, 0);
218 if (type != SCAN_OUT)
221 buffer[(bit_cnt)/8] |= 1 << ((bit_cnt) % 8);
223 buffer[(bit_cnt)/8] &= ~(1 << ((bit_cnt) % 8));
227 int bitbang_execute_queue(void)
229 jtag_command_t *cmd = jtag_command_queue; /* currently processed command */
235 if (!bitbang_interface)
237 ERROR("BUG: Bitbang interface called, but not yet initialized");
241 /* return ERROR_OK, unless a jtag_read_buffer returns a failed check
242 * that wasn't handled by a caller-provided error handler
246 if(bitbang_interface->blink)
247 bitbang_interface->blink(1);
254 #ifdef _DEBUG_JTAG_IO_
255 DEBUG("end_state: %i", cmd->cmd.end_state->end_state);
257 if (cmd->cmd.end_state->end_state != -1)
258 bitbang_end_state(cmd->cmd.end_state->end_state);
261 #ifdef _DEBUG_JTAG_IO_
262 DEBUG("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
264 if (cmd->cmd.reset->trst == 1)
268 bitbang_interface->reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
271 #ifdef _DEBUG_JTAG_IO_
272 DEBUG("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, cmd->cmd.runtest->end_state);
274 if (cmd->cmd.runtest->end_state != -1)
275 bitbang_end_state(cmd->cmd.runtest->end_state);
276 bitbang_runtest(cmd->cmd.runtest->num_cycles);
279 #ifdef _DEBUG_JTAG_IO_
280 DEBUG("statemove end in %i", cmd->cmd.statemove->end_state);
282 if (cmd->cmd.statemove->end_state != -1)
283 bitbang_end_state(cmd->cmd.statemove->end_state);
284 bitbang_state_move();
287 #ifdef _DEBUG_JTAG_IO_
288 DEBUG("pathmove: %i states, end in %i", cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
290 bitbang_path_move(cmd->cmd.pathmove);
293 #ifdef _DEBUG_JTAG_IO_
294 DEBUG("%s scan end in %i", (cmd->cmd.scan->ir_scan) ? "IR" : "DR", cmd->cmd.scan->end_state);
296 if (cmd->cmd.scan->end_state != -1)
297 bitbang_end_state(cmd->cmd.scan->end_state);
298 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
299 type = jtag_scan_type(cmd->cmd.scan);
300 bitbang_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size);
301 if (jtag_read_buffer(buffer, cmd->cmd.scan) != ERROR_OK)
302 retval = ERROR_JTAG_QUEUE_FAILED;
307 #ifdef _DEBUG_JTAG_IO_
308 DEBUG("sleep %i", cmd->cmd.sleep->us);
310 jtag_sleep(cmd->cmd.sleep->us);
313 ERROR("BUG: unknown JTAG command type encountered");
318 if(bitbang_interface->blink)
319 bitbang_interface->blink(0);