使用 OpenOCD（和 Bus Pirate）研究 Raspberry Pi 上的 Jtag答案

【问题标题】：Investigating Jtag on the Raspberry Pi using OpenOCD (and Bus Pirate)使用 OpenOCD（和 Bus Pirate）研究 Raspberry Pi 上的 Jtag
【发布时间】：2015-05-05 22:07:55
【问题描述】：

我买了一个 Bus Pirate 作为开始在几个芯片上调查 Jtag 的廉价方式。我认为 raspberry pi 会成为一个很好的测试用例，因为它有据可查并且拥有庞大的支持社区。在阅读了几个站点后，我了解到这在任何一端都不是一个好的设置，因为总线盗版的 Jtag 功能非常有限，并且 Pi 默认情况下没有打开 Jtag。但是，这是我必须处理的事情，所以如果可能的话，我想看看它。

我安装了最新版本的 OpenOCD (0.9.0)，我的 bus pirate V4 硬件升级到了固件 v6.1 r1676 和 Bootloader v4.4。我在 /dev/ttyUSB0 上有我的公共汽车海盗，并通过回声确认它正在接收命令。我创建了一个 openocd.cfg 文件来选择我的接口和目标。它包含

source [find tcl/interface/buspirate.cfg]
source [find tcl/target/raspberry.cfg]

我更改了我的 buspirate.cfg，使其包含以下内容

#
# Buspirate with OpenOCD support
#
# http://dangerousprototypes.com/bus-pirate-manual/
#

interface buspirate

# you need to specify port on which BP lives (I have a udev rule for this)
buspirate_port /dev/ttyUSB0

# communication speed setting
buspirate_speed normal ;# or fast

# voltage regulator Enabled = 1 Disabled = 0
#buspirate_vreg 0

# pin mode normal or open-drain
#buspirate_mode normal

# pullup state Enabled = 1 Disabled = 0
#buspirate_pullup 0

# this depends on the cable, you are safe with this option
reset_config srst_only

我根据here 找到的教程创建了一个 raspberry.cfg。我还使用了这个站点的脚本来打开 Pi 的 Jtag 引脚。

adapter_khz 1000
adapter_nsrst_delay 400
reset_config none

if { [info exists CHIPNAME] } {
set _CHIPNAME $CHIPNAME
} else {
set _CHIPNAME rspi
}

if { [info exists CPU_TAPID ] } {
set _CPU_TAPID $CPU_TAPID
} else {
set _CPU_TAPID 0x07b7617F
}

jtag newtap $_CHIPNAME arm -irlen 5 -expected-id $_CPU_TAPID

set _TARGETNAME $_CHIPNAME.arm
target create $_TARGETNAME arm11 -chain-position $_TARGETNAME
rspi.arm configure -event gdb-attach { halt }

当我运行 OpenOCD 时，输出表明文件已找到并且它正在与总线盗版连接，但是，它没有与 Pi 正确通信。以下是详细的调试，如果您有任何想法，请告诉我

Open On-Chip Debugger 0.9.0-dev-00424-g2e00235 (2015-04-24-08:50)
Licensed under GNU GPL v2
For bug reports, read
    http://openocd.org/doc/doxygen/bugs.html
User : 13 4 command.c:546 command_print(): debug_level: 3
Debug: 14 4 options.c:98 add_default_dirs(): bindir=/usr/local/bin
Debug: 15 4 options.c:99 add_default_dirs(): pkgdatadir=/usr/local/share/openocd
Debug: 16 4 options.c:100 add_default_dirs(): run_prefix=
Debug: 17 5 configuration.c:44 add_script_search_dir(): adding /home/user/.openocd
Debug: 18 5 configuration.c:44 add_script_search_dir(): adding /usr/local/share/openocd/site
Debug: 19 5 configuration.c:44 add_script_search_dir(): adding /usr/local/share/openocd/scripts
Debug: 20 5 configuration.c:84 find_file(): found openocd.cfg
Debug: 21 5 configuration.c:84 find_file(): found tcl/interface/buspirate.cfg
Debug: 22 6 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_interface buspirate
Debug: 23 6 command.c:145 script_debug(): command - interface ocd_interface buspirate
Debug: 25 6 command.c:325 command_new(): BUG: command 'buspirate_adc' does not have the '.usage' field filled out
Debug: 26 6 command.c:366 register_command_handler(): registering 'ocd_buspirate_adc'...
Debug: 27 6 command.c:366 register_command_handler(): registering 'ocd_buspirate_vreg'...
Debug: 28 6 command.c:366 register_command_handler(): registering 'ocd_buspirate_pullup'...
Debug: 29 7 command.c:366 register_command_handler(): registering 'ocd_buspirate_led'...
Debug: 30 7 command.c:366 register_command_handler(): registering 'ocd_buspirate_speed'...
Debug: 31 7 command.c:366 register_command_handler(): registering 'ocd_buspirate_mode'...
Debug: 32 7 command.c:366 register_command_handler(): registering 'ocd_buspirate_port'...
Warn : 33 7 adapter.c:161 handle_interface_command(): Adapter driver 'buspirate' did not declare which transports it allows; assuming legacy JTAG-only
Info : 34 7 transport.c:118 allow_transports(): only one transport option; autoselect 'jtag'
Debug: 35 8 command.c:366 register_command_handler(): registering 'ocd_jtag_flush_queue_sleep'...
Debug: 36 8 command.c:366 register_command_handler(): registering 'ocd_jtag_rclk'...
Debug: 37 8 command.c:366 register_command_handler(): registering 'ocd_jtag_ntrst_delay'...
Debug: 38 8 command.c:366 register_command_handler(): registering 'ocd_jtag_ntrst_assert_width'...
Debug: 39 8 command.c:366 register_command_handler(): registering 'ocd_scan_chain'...
Debug: 40 8 command.c:366 register_command_handler(): registering 'ocd_jtag_reset'...
Debug: 41 8 command.c:366 register_command_handler(): registering 'ocd_runtest'...
Debug: 42 8 command.c:366 register_command_handler(): registering 'ocd_irscan'...
Debug: 43 8 command.c:366 register_command_handler(): registering 'ocd_verify_ircapture'...
Debug: 44 8 command.c:366 register_command_handler(): registering 'ocd_verify_jtag'...
Debug: 45 9 command.c:366 register_command_handler(): registering 'ocd_tms_sequence'...
Debug: 46 9 command.c:366 register_command_handler(): registering 'ocd_wait_srst_deassert'...
Debug: 47 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 48 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 49 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 50 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 51 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 52 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 53 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 54 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 55 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 56 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 57 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 58 9 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 59 10 command.c:366 register_command_handler(): registering 'ocd_jtag'...
Debug: 60 10 command.c:366 register_command_handler(): registering 'ocd_svf'...
Debug: 61 10 command.c:366 register_command_handler(): registering 'ocd_xsvf'...
Debug: 62 10 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_buspirate_port /dev/ttyUSB0
Debug: 63 10 command.c:145 script_debug(): command - buspirate_port ocd_buspirate_port /dev/ttyUSB0
Debug: 65 10 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_buspirate_speed normal
Debug: 66 10 command.c:145 script_debug(): command - buspirate_speed ocd_buspirate_speed normal
Debug: 68 10 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_reset_config srst_only
Debug: 69 10 command.c:145 script_debug(): command - reset_config ocd_reset_config srst_only
User : 71 10 command.c:546 command_print(): srst_only separate srst_gates_jtag srst_open_drain connect_deassert_srst
Debug: 72 10 configuration.c:84 find_file(): found tcl/target/raspberry.cfg
Debug: 73 10 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_adapter_khz 1000
Debug: 74 10 command.c:145 script_debug(): command - adapter_khz ocd_adapter_khz 1000
Debug: 76 10 core.c:1629 jtag_config_khz(): handle jtag khz
Debug: 77 10 core.c:1596 adapter_khz_to_speed(): convert khz to interface specific speed value
Debug: 78 10 core.c:1596 adapter_khz_to_speed(): convert khz to interface specific speed value
User : 79 10 command.c:546 command_print(): adapter speed: 1000 kHz
Debug: 80 10 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_adapter_nsrst_delay 400
Debug: 81 10 command.c:145 script_debug(): command - adapter_nsrst_delay ocd_adapter_nsrst_delay 400
User : 83 10 command.c:546 command_print(): adapter_nsrst_delay: 400
Debug: 84 11 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_reset_config none
Debug: 85 11 command.c:145 script_debug(): command - reset_config ocd_reset_config none
User : 87 11 command.c:546 command_print(): none separate
Debug: 88 11 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_jtag newtap rspi arm -irlen 5 -expected-id 0x07b7617F
Debug: 89 11 command.c:145 script_debug(): command - ocd_jtag ocd_jtag newtap rspi arm -irlen 5 -expected-id 0x07b7617F
Debug: 90 11 tcl.c:549 jim_newtap_cmd(): Creating New Tap, Chip: rspi, Tap: arm, Dotted: rspi.arm, 4 params
Debug: 91 11 tcl.c:573 jim_newtap_cmd(): Processing option: -irlen
Debug: 92 11 tcl.c:573 jim_newtap_cmd(): Processing option: -expected-id
Debug: 93 11 core.c:1302 jtag_tap_init(): Created Tap: rspi.arm @ abs position 0, irlen 5, capture: 0x1 mask: 0x3
Debug: 94 11 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_target create rspi.arm arm11 -chain-position rspi.arm
Debug: 95 11 command.c:145 script_debug(): command - ocd_target ocd_target create rspi.arm arm11 -chain-position rspi.arm
Debug: 96 11 target.c:1837 target_free_all_working_areas_restore(): freeing all working areas
Debug: 97 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 98 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 99 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 100 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 101 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 102 11 command.c:366 register_command_handler(): registering 'ocd_arm'...
Debug: 103 11 command.c:366 register_command_handler(): registering 'ocd_etm'...
Debug: 104 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 105 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 106 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 107 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 108 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 109 11 command.c:366 register_command_handler(): registering 'ocd_arm11'...
Debug: 110 11 armv4_5.c:422 arm_set_cpsr(): set CPSR 0x00000010: User mode, ARM state
Debug: 111 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 112 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 113 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 114 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 115 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 116 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 117 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 118 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 119 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 120 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 121 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 122 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 123 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 124 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 125 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 126 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 127 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 128 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 129 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 130 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 131 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 132 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 133 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 134 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 135 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 136 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 137 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 138 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 139 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 140 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 141 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 142 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 143 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 144 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 145 12 command.c:366 register_command_handler(): registering 'ocd_rspi.arm'...
Debug: 146 12 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_rspi.arm configure -event gdb-attach halt
Debug: 147 12 command.c:145 script_debug(): command - ocd_rspi.arm ocd_rspi.arm configure -event gdb-attach halt
Debug: 148 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_init
Debug: 149 13 command.c:145 script_debug(): command - init ocd_init
Debug: 151 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_target init
Debug: 152 13 command.c:145 script_debug(): command - ocd_target ocd_target init
Debug: 154 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_target names
Debug: 155 13 command.c:145 script_debug(): command - ocd_target ocd_target names
Debug: 156 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_rspi.arm cget -event gdb-flash-erase-start
Debug: 157 13 command.c:145 script_debug(): command - ocd_rspi.arm ocd_rspi.arm cget -event gdb-flash-erase-start
Debug: 158 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_rspi.arm configure -event gdb-flash-erase-start reset init
Debug: 159 13 command.c:145 script_debug(): command - ocd_rspi.arm ocd_rspi.arm configure -event gdb-flash-erase-start reset init
Debug: 160 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_rspi.arm cget -event gdb-flash-write-end
Debug: 161 13 command.c:145 script_debug(): command - ocd_rspi.arm ocd_rspi.arm cget -event gdb-flash-write-end
Debug: 162 13 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_rspi.arm configure -event gdb-flash-write-end reset halt
Debug: 163 13 command.c:145 script_debug(): command - ocd_rspi.arm ocd_rspi.arm configure -event gdb-flash-write-end reset halt
Debug: 164 13 target.c:1313 handle_target_init_command(): Initializing targets...
Debug: 165 13 command.c:366 register_command_handler(): registering 'ocd_target_request'...
Debug: 166 13 command.c:366 register_command_handler(): registering 'ocd_trace'...
Debug: 167 13 command.c:366 register_command_handler(): registering 'ocd_trace'...
Debug: 168 13 command.c:366 register_command_handler(): registering 'ocd_fast_load_image'...
Debug: 169 13 command.c:366 register_command_handler(): registering 'ocd_fast_load'...
Debug: 170 13 command.c:366 register_command_handler(): registering 'ocd_profile'...
Debug: 171 13 command.c:366 register_command_handler(): registering 'ocd_virt2phys'...
Debug: 172 14 command.c:366 register_command_handler(): registering 'ocd_reg'...
Debug: 173 14 command.c:366 register_command_handler(): registering 'ocd_poll'...
Debug: 174 14 command.c:366 register_command_handler(): registering 'ocd_wait_halt'...
Debug: 175 14 command.c:366 register_command_handler(): registering 'ocd_halt'...
Debug: 176 14 command.c:366 register_command_handler(): registering 'ocd_resume'...
Debug: 177 14 command.c:366 register_command_handler(): registering 'ocd_reset'...
Debug: 178 14 command.c:366 register_command_handler(): registering 'ocd_soft_reset_halt'...
Debug: 179 14 command.c:366 register_command_handler(): registering 'ocd_step'...
Debug: 180 14 command.c:366 register_command_handler(): registering 'ocd_mdw'...
Debug: 181 14 command.c:366 register_command_handler(): registering 'ocd_mdh'...
Debug: 182 14 command.c:366 register_command_handler(): registering 'ocd_mdb'...
Debug: 183 14 command.c:366 register_command_handler(): registering 'ocd_mww'...
Debug: 184 14 command.c:366 register_command_handler(): registering 'ocd_mwh'...
Debug: 185 14 command.c:366 register_command_handler(): registering 'ocd_mwb'...
Debug: 186 14 command.c:366 register_command_handler(): registering 'ocd_bp'...
Debug: 187 14 command.c:366 register_command_handler(): registering 'ocd_rbp'...
Debug: 188 14 command.c:366 register_command_handler(): registering 'ocd_wp'...
Debug: 189 14 command.c:366 register_command_handler(): registering 'ocd_rwp'...
Debug: 190 14 command.c:366 register_command_handler(): registering 'ocd_load_image'...
Debug: 191 14 command.c:366 register_command_handler(): registering 'ocd_dump_image'...
Debug: 192 14 command.c:366 register_command_handler(): registering 'ocd_verify_image'...
Debug: 193 14 command.c:366 register_command_handler(): registering 'ocd_test_image'...
Debug: 194 14 command.c:366 register_command_handler(): registering 'ocd_reset_nag'...
Debug: 195 14 command.c:366 register_command_handler(): registering 'ocd_ps'...
Debug: 196 14 command.c:366 register_command_handler(): registering 'ocd_test_mem_access'...
Info : 197 116 buspirate.c:232 read_and_discard_all_data(): Some stale data from a previous connection was discarded.
Debug: 198 218 buspirate.c:834 buspirate_jtag_enable(): Entering binary mode
Debug: 199 218 buspirate.c:1059 buspirate_serial_write(): size = 20 ret = 20
Debug: 200 218 buspirate.c:1121 buspirate_print_buffer(): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 
Debug: 201 218 buspirate.c:1127 buspirate_print_buffer(): 00 00 00 00 
Debug: 202 229 buspirate.c:1091 buspirate_serial_read(): should have read = 4 actual size = 4
Debug: 203 229 buspirate.c:1127 buspirate_print_buffer(): 42 42 49 4f 
Debug: 204 229 buspirate.c:1091 buspirate_serial_read(): should have read = 1 actual size = 1
Debug: 205 229 buspirate.c:1127 buspirate_print_buffer(): 31 
Debug: 206 229 buspirate.c:1059 buspirate_serial_write(): size = 1 ret = 1
Debug: 207 229 buspirate.c:1127 buspirate_print_buffer(): 06 
Debug: 208 233 buspirate.c:1091 buspirate_serial_read(): should have read = 4 actual size = 4
Debug: 209 233 buspirate.c:1127 buspirate_print_buffer(): 4f 43 44 31 
Info : 210 233 buspirate.c:305 buspirate_init(): Buspirate Interface ready!
Debug: 211 233 buspirate.c:1059 buspirate_serial_write(): size = 2 ret = 2
Debug: 212 233 buspirate.c:1127 buspirate_print_buffer(): 01 02 
Debug: 213 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 214 233 buspirate.c:1127 buspirate_print_buffer(): 02 02 00 
Debug: 215 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 216 233 buspirate.c:1127 buspirate_print_buffer(): 02 10 00 
Debug: 217 233 buspirate.c:809 buspirate_reset(): trst: 0, srst: 0
Debug: 218 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 219 233 buspirate.c:1127 buspirate_print_buffer(): 02 04 01 
Debug: 220 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 221 233 buspirate.c:1127 buspirate_print_buffer(): 02 08 01 
Info : 222 233 core.c:1355 adapter_init(): This adapter doesn't support configurable speed
Debug: 223 233 openocd.c:137 handle_init_command(): Debug Adapter init complete
Debug: 224 233 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_transport init
Debug: 225 233 command.c:145 script_debug(): command - ocd_transport ocd_transport init
Debug: 227 233 transport.c:240 handle_transport_init(): handle_transport_init
Debug: 228 233 buspirate.c:809 buspirate_reset(): trst: 0, srst: 0
Debug: 229 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 230 233 buspirate.c:1127 buspirate_print_buffer(): 02 04 01 
Debug: 231 233 buspirate.c:1059 buspirate_serial_write(): size = 3 ret = 3
Debug: 232 233 buspirate.c:1127 buspirate_print_buffer(): 02 08 01 
Debug: 233 233 core.c:730 jtag_add_reset(): SRST line released
Debug: 234 233 core.c:754 jtag_add_reset(): TRST line released
Debug: 235 233 core.c:328 jtag_call_event_callbacks(): jtag event: TAP reset
Debug: 237 656 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_jtag arp_init
Debug: 238 656 command.c:145 script_debug(): command - ocd_jtag ocd_jtag arp_init
Debug: 239 656 core.c:1397 jtag_init_inner(): Init JTAG chain
Debug: 240 656 core.c:328 jtag_call_event_callbacks(): jtag event: TAP reset
Debug: 241 656 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 7 scans = 0
Debug: 242 656 buspirate.c:1059 buspirate_serial_write(): size = 5 ret = 5
Debug: 243 656 buspirate.c:1127 buspirate_print_buffer(): 05 00 07 00 7f 
Debug: 244 660 buspirate.c:1091 buspirate_serial_read(): should have read = 4 actual size = 4
Debug: 245 660 buspirate.c:1127 buspirate_print_buffer(): 05 00 07 7f 
Debug: 246 660 core.c:1058 jtag_examine_chain(): DR scan interrogation for IDCODE/BYPASS
Debug: 247 660 core.c:328 jtag_call_event_callbacks(): jtag event: TAP reset
Debug: 248 660 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 687 scans = 1
Debug: 249 660 buspirate.c:1059 buspirate_serial_write(): size = 175 ret = 175
Debug: 250 660 buspirate.c:1121 buspirate_print_buffer(): 05 02 af 80 17 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 251 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 252 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 253 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 254 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 255 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 256 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 257 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 258 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 259 660 buspirate.c:1121 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 00 ff 
Debug: 260 660 buspirate.c:1127 buspirate_print_buffer(): 00 ff 00 ff 00 ff 00 ff 00 ff 00 7f 40 00 7f 
Debug: 261 686 buspirate.c:1091 buspirate_serial_read(): should have read = 89 actual size = 89
Debug: 262 686 buspirate.c:1121 buspirate_print_buffer(): 05 02 af ff ff ff ff ff ff ff ff ff ff ff ff ff 
Debug: 263 686 buspirate.c:1121 buspirate_print_buffer(): ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 
Debug: 264 686 buspirate.c:1121 buspirate_print_buffer(): ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 
Debug: 265 686 buspirate.c:1121 buspirate_print_buffer(): ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 
Debug: 266 686 buspirate.c:1121 buspirate_print_buffer(): ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff 
Debug: 267 686 buspirate.c:1127 buspirate_print_buffer(): ff ff ff ff ff ff ff ff 7f 
Error: 268 686 core.c:948 jtag_examine_chain_check(): JTAG scan chain interrogation failed: all ones
Error: 269 686 core.c:949 jtag_examine_chain_check(): Check JTAG interface, timings, target power, etc.
Error: 270 686 core.c:1442 jtag_init_inner(): Trying to use configured scan chain anyway...
Debug: 271 686 core.c:1188 jtag_validate_ircapture(): IR capture validation scan
Debug: 272 686 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 18 scans = 1
Debug: 273 686 buspirate.c:1059 buspirate_serial_write(): size = 9 ret = 9
Debug: 274 686 buspirate.c:1127 buspirate_print_buffer(): 05 00 12 80 1b 3f a0 00 01 
Debug: 275 690 buspirate.c:1091 buspirate_serial_read(): should have read = 6 actual size = 6
Debug: 276 690 buspirate.c:1127 buspirate_print_buffer(): 05 00 12 ff ff 03 
Error: 277 690 core.c:1240 jtag_validate_ircapture(): rspi.arm: IR capture error; saw 0x1f not 0x01
Debug: 278 690 core.c:328 jtag_call_event_callbacks(): jtag event: TAP reset
Debug: 279 690 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 7 scans = 0
Debug: 280 690 buspirate.c:1059 buspirate_serial_write(): size = 5 ret = 5
Debug: 281 690 buspirate.c:1127 buspirate_print_buffer(): 05 00 07 00 7f 
Debug: 282 694 buspirate.c:1091 buspirate_serial_read(): should have read = 4 actual size = 4
Debug: 283 694 buspirate.c:1127 buspirate_print_buffer(): 05 00 07 7f 
Warn : 284 694 core.c:1465 jtag_init_inner(): Bypassing JTAG setup events due to errors
Debug: 285 694 openocd.c:150 handle_init_command(): Examining targets...
Debug: 286 694 target.c:1465 target_call_event_callbacks(): target event 21 (examine-start)
Debug: 287 694 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 74 scans = 4
Debug: 288 694 buspirate.c:1059 buspirate_serial_write(): size = 23 ret = 23
Debug: 289 694 buspirate.c:1121 buspirate_print_buffer(): 05 00 4a 00 1b 0f e8 00 00 00 00 00 00 00 00 00 
Debug: 290 694 buspirate.c:1127 buspirate_print_buffer(): 7a 04 a0 00 03 00 01 
Debug: 291 700 buspirate.c:1091 buspirate_serial_read(): should have read = 13 actual size = 13
Debug: 292 700 buspirate.c:1127 buspirate_print_buffer(): 05 00 4a ff ff ff ff ff ff ff ff ff 03 
Error: 293 700 arm11_dbgtap.c:164 arm11_in_handler_SCAN_N(): 'arm11 target' JTAG error SCREG OUT 0x1f
Debug: 294 700 buspirate.c:675 buspirate_tap_execute(): executing tap num bits = 61 scans = 2
Debug: 295 700 buspirate.c:1059 buspirate_serial_write(): size = 19 ret = 19
Debug: 296 700 buspirate.c:1121 buspirate_print_buffer(): 05 00 3d 00 0f 03 74 00 00 00 00 00 00 00 00 00 
Debug: 297 700 buspirate.c:1127 buspirate_print_buffer(): 00 00 0d 
Debug: 298 705 buspirate.c:1091 buspirate_serial_read(): should have read = 11 actual size = 11
Debug: 299 705 buspirate.c:1127 buspirate_print_buffer(): 05 00 3d ff ff ff ff ff ff ff 1f 
Error: 300 705 arm11.c:1157 arm11_examine(): unexpected ARM11 ID code
Debug: 301 705 openocd.c:152 handle_init_command(): target examination failed
Debug: 302 705 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_flash init
Debug: 303 705 command.c:145 script_debug(): command - ocd_flash ocd_flash init
Debug: 305 705 tcl.c:890 handle_flash_init_command(): Initializing flash devices...
Debug: 306 705 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_mflash init
Debug: 307 705 command.c:145 script_debug(): command - ocd_mflash ocd_mflash init
Debug: 309 705 mflash.c:1379 handle_mflash_init_command(): Initializing mflash devices...
Debug: 310 705 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_nand init
Debug: 311 705 command.c:145 script_debug(): command - ocd_nand ocd_nand init
Debug: 313 705 tcl.c:497 handle_nand_init_command(): Initializing NAND devices...
Debug: 314 706 command.c:145 script_debug(): command - ocd_command ocd_command type ocd_pld init
Debug: 315 706 command.c:145 script_debug(): command - ocd_pld ocd_pld init
Debug: 317 706 pld.c:207 handle_pld_init_command(): Initializing PLDs...

【问题讨论】：

发现盗版巴士的硬件版本居然是V3。这是一个有趣的板。

标签： raspberry-pi jtag openocd

【解决方案1】：

我认为您会发现最大的问题是 Raspberry Pi 使用的是 Broadcom BCM28XX 芯片。
这些用于机顶盒，获取数据表或模型 (BSDL) 需要向 Broadcom 提供 NDA。

我希望 Pi 在工厂使用 JTAG 进行测试，但 BCM 芯片很可能有安全保险丝，一旦序列号被编程，这些保险丝就会在生产过程结束时熔断。
随着保险丝熔断，JTAG 链将被破坏。

如果数据表和 BSDL 文件是公开发布的，那么任何人都可以“修改”他们的机顶盒，而机顶盒的供应商可能会有点不高兴。
我认为您会遇到的另一个问题是，BCM 芯片中的功能比标准 JTAG 兼容设备可能具有的更多功能。
我猜 BCM 是 ASIC 的一部分，带有某种内部闪存，可能还有 PLA（FPGA 或 CPLD）。
他们也有一个 ARM 核心处理器。

祝你好运，但 Pi 不是我用作 JTAG 培训平台的板。

【讨论】：

【解决方案2】：

我能够使用 V3 sparkfun 板来完成这项工作。我有一个小得多的巴士海盗配置文件：

source [find interface/buspirate.cfg]
interface buspirate
buspirate_port /dev/ttyUSB0
buspirate_vreg 0
buspirate_mode open-drain
buspirate_pullup 1
buspirate_speed normal

我发布了所有详细信息on my github PiOCD wiki

简而言之，我浪费了几个小时的最大问题是我错误地猜出了我的实验设备（LinksSys BEFSR41 路由器）上的 jtag 引脚。我没有看到您尝试连接到 Bus Pirate jtag 连接器的设备。

我这样启动 OpenOCD：

sudo openocd -s /usr/share/openocd -f board/buspirate.cfg

这就是我所看到的：

Open On-Chip Debugger 0.10.0-dev-00040-gd52070c (2015-10-09-16:51)
Licensed under GNU GPL v2
For bug reports, read
        http://openocd.org/doc/doxygen/bugs.html
Warn : Adapter driver 'buspirate' did not declare which transports it allows; assuming legacy JTAG-only
Info : only one transport option; autoselect 'jtag'
srst_only separate srst_gates_jtag srst_open_drain connect_deassert_srst
Warn : Interface already configured, ignoring
Info : Buspirate Interface ready!
Info : This adapter doesn't support configurable speed
Warn : There are no enabled taps.  AUTO PROBING MIGHT NOT WORK!!
Info : JTAG tap: auto0.tap tap/device found: 0x1f0f0f0f (mfg: 0x787, part: 0xf0f0, ver: 0x1)
Warn : AUTO auto0.tap - use "jtag newtap auto0 tap -irlen 4 -expected-id 0x1f0f0f0f"
Warn : gdb services need one or more targets defined

在您发帖几个月后，希望这仍然对您有所帮助 :)

【讨论】：