1 /***************************************************************************
2 * Copyright (C) 2008 by Øyvind Harboe *
3 * oyvind.harboe@zylin.com *
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 ***************************************************************************/
24 #include "replacements.h"
30 /* my private tap controller state, which tracks state for calling code */
31 static tap_state_t dummy_state = TAP_RESET;
33 static int dummy_clock; /* edge detector */
35 static int clock_count; /* count clocks in any stable state, only stable states */
37 static u32 dummy_data;
40 static int dummy_speed(int speed);
41 static int dummy_register_commands(struct command_context_s *cmd_ctx);
42 static int dummy_init(void);
43 static int dummy_quit(void);
44 static int dummy_khz(int khz, int *jtag_speed);
45 static int dummy_speed_div(int speed, int *khz);
48 /* The dummy driver is used to easily check the code path
49 * where the target is unresponsive.
51 jtag_interface_t dummy_interface =
55 .execute_queue = bitbang_execute_queue,
58 .register_commands = dummy_register_commands,
60 .speed_div = dummy_speed_div,
66 static int dummy_read(void);
67 static void dummy_write(int tck, int tms, int tdi);
68 static void dummy_reset(int trst, int srst);
69 static void dummy_led(int on);
71 static bitbang_interface_t dummy_bitbang =
79 static int dummy_read(void)
81 int data = 1 & dummy_data;
82 dummy_data = (dummy_data >> 1) | (1<<31);
87 static void dummy_write(int tck, int tms, int tdi)
89 /* TAP standard: "state transitions occur on rising edge of clock" */
90 if( tck != dummy_clock )
94 tap_state_t old_state = dummy_state;
95 dummy_state = tap_state_transition( old_state, tms );
97 if( old_state != dummy_state )
101 LOG_DEBUG("dummy_tap: %d stable clocks", clock_count);
105 LOG_DEBUG("dummy_tap: %s", tap_state_name(dummy_state) );
108 if(dummy_state == TAP_DRCAPTURE)
109 dummy_data = 0x01255043;
114 /* this is a stable state clock edge, no change of state here,
115 * simply increment clock_count for subsequent logging
124 static void dummy_reset(int trst, int srst)
128 if (trst || (srst && (jtag_reset_config & RESET_SRST_PULLS_TRST)))
129 dummy_state = TAP_RESET;
131 LOG_DEBUG("reset to: %s", tap_state_name(dummy_state) );
134 static int dummy_khz(int khz, int *jtag_speed)
142 *jtag_speed=64000/khz;
147 static int dummy_speed_div(int speed, int *khz)
161 static int dummy_speed(int speed)
166 static int dummy_register_commands(struct command_context_s *cmd_ctx)
171 static int dummy_init(void)
173 bitbang_interface = &dummy_bitbang;
178 static int dummy_quit(void)
183 static void dummy_led(int on)