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 "interface.h"
28 /* my private tap controller state, which tracks state for calling code */
29 static tap_state_t dummy_state
= TAP_RESET
;
31 static int dummy_clock
; /* edge detector */
33 static int clock_count
; /* count clocks in any stable state, only stable states */
35 static uint32_t dummy_data
;
38 static int dummy_speed(int speed
);
39 static int dummy_register_commands(struct command_context
*cmd_ctx
);
40 static int dummy_init(void);
41 static int dummy_quit(void);
42 static int dummy_khz(int khz
, int *jtag_speed
);
43 static int dummy_speed_div(int speed
, int *khz
);
46 /* The dummy driver is used to easily check the code path
47 * where the target is unresponsive.
49 struct jtag_interface dummy_interface
=
53 .execute_queue
= bitbang_execute_queue
,
56 .register_commands
= dummy_register_commands
,
58 .speed_div
= dummy_speed_div
,
64 static int dummy_read(void);
65 static void dummy_write(int tck
, int tms
, int tdi
);
66 static void dummy_reset(int trst
, int srst
);
67 static void dummy_led(int on
);
69 static struct bitbang_interface dummy_bitbang
=
77 static int dummy_read(void)
79 int data
= 1 & dummy_data
;
80 dummy_data
= (dummy_data
>> 1) | (1 << 31);
85 static void dummy_write(int tck
, int tms
, int tdi
)
87 /* TAP standard: "state transitions occur on rising edge of clock" */
88 if (tck
!= dummy_clock
)
92 tap_state_t old_state
= dummy_state
;
93 dummy_state
= tap_state_transition(old_state
, tms
);
95 if (old_state
!= dummy_state
)
99 LOG_DEBUG("dummy_tap: %d stable clocks", clock_count
);
103 LOG_DEBUG("dummy_tap: %s", tap_state_name(dummy_state
));
106 if (dummy_state
== TAP_DRCAPTURE
)
107 dummy_data
= 0x01255043;
112 /* this is a stable state clock edge, no change of state here,
113 * simply increment clock_count for subsequent logging
122 static void dummy_reset(int trst
, int srst
)
126 if (trst
|| (srst
&& (jtag_get_reset_config() & RESET_SRST_PULLS_TRST
)))
127 dummy_state
= TAP_RESET
;
129 LOG_DEBUG("reset to: %s", tap_state_name(dummy_state
));
132 static int dummy_khz(int khz
, int *jtag_speed
)
140 *jtag_speed
= 64000/khz
;
145 static int dummy_speed_div(int speed
, int *khz
)
159 static int dummy_speed(int speed
)
164 static int dummy_register_commands(struct command_context
*cmd_ctx
)
169 static int dummy_init(void)
171 bitbang_interface
= &dummy_bitbang
;
176 static int dummy_quit(void)
181 static void dummy_led(int on
)