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 void bitbang_end_state(enum tap_state state)
46 if (tap_move_map[state] != -1)
50 ERROR("BUG: %i is not a valid end state", state);
55 void bitbang_state_move(void) {
58 u8 tms_scan = TAP_MOVE(cur_state, end_state);
60 for (i = 0; i < 7; i++)
62 tms = (tms_scan >> i) & 1;
63 bitbang_interface->write(0, tms, 0);
64 bitbang_interface->write(1, tms, 0);
66 bitbang_interface->write(0, tms, 0);
68 cur_state = end_state;
71 void bitbang_path_move(pathmove_command_t *cmd)
73 int num_states = cmd->num_states;
79 if (tap_transitions[cur_state].low == cmd->path[state_count])
81 bitbang_interface->write(0, 0, 0);
82 bitbang_interface->write(1, 0, 0);
84 else if (tap_transitions[cur_state].high == cmd->path[state_count])
86 bitbang_interface->write(0, 1, 0);
87 bitbang_interface->write(1, 1, 0);
91 ERROR("BUG: %s -> %s isn't a valid TAP transition", tap_state_strings[cur_state], tap_state_strings[cmd->path[state_count]]);
95 cur_state = cmd->path[state_count];
100 end_state = cur_state;
103 void bitbang_runtest(int num_cycles)
107 enum tap_state saved_end_state = end_state;
109 /* only do a state_move when we're not already in RTI */
110 if (cur_state != TAP_RTI)
112 bitbang_end_state(TAP_RTI);
113 bitbang_state_move();
116 /* execute num_cycles */
117 bitbang_interface->write(0, 0, 0);
118 for (i = 0; i < num_cycles; i++)
120 bitbang_interface->write(1, 0, 0);
121 bitbang_interface->write(0, 0, 0);
124 /* finish in end_state */
125 bitbang_end_state(saved_end_state);
126 if (cur_state != end_state)
127 bitbang_state_move();
130 void bitbang_scan(int ir_scan, enum scan_type type, u8 *buffer, int scan_size)
132 enum tap_state saved_end_state = end_state;
135 if (!((!ir_scan && (cur_state == TAP_SD)) || (ir_scan && (cur_state == TAP_SI))))
138 bitbang_end_state(TAP_SI);
140 bitbang_end_state(TAP_SD);
142 bitbang_state_move();
143 bitbang_end_state(saved_end_state);
146 for (bit_cnt = 0; bit_cnt < scan_size; bit_cnt++)
148 /* set TMS high on the last bit unless we want to end in TAP_SD/SI */
150 if ((ir_scan && (end_state == TAP_SI)) ||
151 (!ir_scan && (end_state == TAP_SD)))
155 tms = (bit_cnt==scan_size-1) ? 1 : 0;
158 /* if we're just reading the scan, but don't care about the output
159 * default to outputting 'low', this also makes valgrind traces more readable,
160 * as it removes the dependency on an uninitialised value
162 if ((type != SCAN_IN) && ((buffer[bit_cnt/8] >> (bit_cnt % 8)) & 0x1))
164 bitbang_interface->write(0, (bit_cnt==scan_size-1) ? 1 : 0, 1);
165 bitbang_interface->write(1, (bit_cnt==scan_size-1) ? 1 : 0, 1);
167 bitbang_interface->write(0, (bit_cnt==scan_size-1) ? 1 : 0, 0);
168 bitbang_interface->write(1, (bit_cnt==scan_size-1) ? 1 : 0, 0);
171 if (type != SCAN_OUT)
173 if (bitbang_interface->read())
174 buffer[(bit_cnt)/8] |= 1 << ((bit_cnt) % 8);
176 buffer[(bit_cnt)/8] &= ~(1 << ((bit_cnt) % 8));
181 bitbang_interface->write(0, 0, 0);
182 bitbang_interface->write(1, 0, 0);
189 if (cur_state != end_state)
190 bitbang_state_move();
193 int bitbang_execute_queue(void)
195 jtag_command_t *cmd = jtag_command_queue; /* currently processed command */
201 if (!bitbang_interface)
203 ERROR("BUG: Bitbang interface called, but not yet initialized");
207 /* return ERROR_OK, unless a jtag_read_buffer returns a failed check
208 * that wasn't handled by a caller-provided error handler
217 #ifdef _DEBUG_JTAG_IO_
218 DEBUG("end_state: %i", cmd->cmd.end_state->end_state);
220 if (cmd->cmd.end_state->end_state != -1)
221 bitbang_end_state(cmd->cmd.end_state->end_state);
224 #ifdef _DEBUG_JTAG_IO_
225 DEBUG("reset trst: %i srst %i", cmd->cmd.reset->trst, cmd->cmd.reset->srst);
227 if (cmd->cmd.reset->trst == 1)
231 bitbang_interface->reset(cmd->cmd.reset->trst, cmd->cmd.reset->srst);
234 #ifdef _DEBUG_JTAG_IO_
235 DEBUG("runtest %i cycles, end in %i", cmd->cmd.runtest->num_cycles, cmd->cmd.runtest->end_state);
237 if (cmd->cmd.runtest->end_state != -1)
238 bitbang_end_state(cmd->cmd.runtest->end_state);
239 bitbang_runtest(cmd->cmd.runtest->num_cycles);
242 #ifdef _DEBUG_JTAG_IO_
243 DEBUG("statemove end in %i", cmd->cmd.statemove->end_state);
245 if (cmd->cmd.statemove->end_state != -1)
246 bitbang_end_state(cmd->cmd.statemove->end_state);
247 bitbang_state_move();
250 #ifdef _DEBUG_JTAG_IO_
251 DEBUG("pathmove: %i states, end in %i", cmd->cmd.pathmove->num_states, cmd->cmd.pathmove->path[cmd->cmd.pathmove->num_states - 1]);
253 bitbang_path_move(cmd->cmd.pathmove);
256 #ifdef _DEBUG_JTAG_IO_
257 DEBUG("%s scan end in %i", (cmd->cmd.scan->ir_scan) ? "IR" : "DR", cmd->cmd.scan->end_state);
259 if (cmd->cmd.scan->end_state != -1)
260 bitbang_end_state(cmd->cmd.scan->end_state);
261 scan_size = jtag_build_buffer(cmd->cmd.scan, &buffer);
262 type = jtag_scan_type(cmd->cmd.scan);
263 bitbang_scan(cmd->cmd.scan->ir_scan, type, buffer, scan_size);
264 if (jtag_read_buffer(buffer, cmd->cmd.scan) != ERROR_OK)
265 retval = ERROR_JTAG_QUEUE_FAILED;
270 #ifdef _DEBUG_JTAG_IO_
271 DEBUG("sleep %i", cmd->cmd.sleep->us);
273 jtag_sleep(cmd->cmd.sleep->us);
276 ERROR("BUG: unknown JTAG command type encountered");