arch/arm/Kconfig.debug

   1 menu "Kernel hacking"
   2
   3 source "lib/Kconfig.debug"
   4
   5 config STRICT_DEVMEM
   6         bool "Filter access to /dev/mem"
   7         depends on MMU
   8         ---help---
   9           If this option is disabled, you allow userspace (root) access to all
  10           of memory, including kernel and userspace memory. Accidental
  11           access to this is obviously disastrous, but specific access can
  12           be used by people debugging the kernel.
  13
  14           If this option is switched on, the /dev/mem file only allows
  15           userspace access to memory mapped peripherals.
  16
  17           If in doubt, say Y.
  18
  19 # RMK wants arm kernels compiled with frame pointers or stack unwinding.
  20 # If you know what you are doing and are willing to live without stack
  21 # traces, you can get a slightly smaller kernel by setting this option to
  22 # n, but then RMK will have to kill you ;).
  23 config FRAME_POINTER
  24         bool
  25         depends on !THUMB2_KERNEL
  26         default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER
  27         help
  28           If you say N here, the resulting kernel will be slightly smaller and
  29           faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,
  30           when a problem occurs with the kernel, the information that is
  31           reported is severely limited.
  32
  33 config ARM_UNWIND
  34         bool "Enable stack unwinding support (EXPERIMENTAL)"
  35         depends on AEABI && EXPERIMENTAL
  36         default y
  37         help
  38           This option enables stack unwinding support in the kernel
  39           using the information automatically generated by the
  40           compiler. The resulting kernel image is slightly bigger but
  41           the performance is not affected. Currently, this feature
  42           only works with EABI compilers. If unsure say Y.
  43
  44 config OLD_MCOUNT
  45         bool
  46         depends on FUNCTION_TRACER && FRAME_POINTER
  47         default y
  48
  49 config DEBUG_USER
  50         bool "Verbose user fault messages"
  51         help
  52           When a user program crashes due to an exception, the kernel can
  53           print a brief message explaining what the problem was. This is
  54           sometimes helpful for debugging but serves no purpose on a
  55           production system. Most people should say N here.
  56
  57           In addition, you need to pass user_debug=N on the kernel command
  58           line to enable this feature.  N consists of the sum of:
  59
  60               1 - undefined instruction events
  61               2 - system calls
  62               4 - invalid data aborts
  63               8 - SIGSEGV faults
  64              16 - SIGBUS faults
  65
  66 # These options are only for real kernel hackers who want to get their hands dirty.
  67 config DEBUG_LL
  68         bool "Kernel low-level debugging functions (read help!)"
  69         depends on DEBUG_KERNEL
  70         help
  71           Say Y here to include definitions of printascii, printch, printhex
  72           in the kernel.  This is helpful if you are debugging code that
  73           executes before the console is initialized.
  74
  75           Note that selecting this option will limit the kernel to a single
  76           UART definition, as specified below. Attempting to boot the kernel
  77           image on a different platform *will not work*, so this option should
  78           not be enabled for kernels that are intended to be portable.
  79
  80 choice
  81         prompt "Kernel low-level debugging port"
  82         depends on DEBUG_LL
  83
  84         config AT91_DEBUG_LL_DBGU0
  85                 bool "Kernel low-level debugging on rm9200, 9260/9g20, 9261/9g10 and 9rl"
  86                 depends on HAVE_AT91_DBGU0
  87
  88         config AT91_DEBUG_LL_DBGU1
  89                 bool "Kernel low-level debugging on 9263 and 9g45"
  90                 depends on HAVE_AT91_DBGU1
  91
  92         config DEBUG_CLPS711X_UART1
  93                 bool "Kernel low-level debugging messages via UART1"
  94                 depends on ARCH_CLPS711X
  95                 help
  96                   Say Y here if you want the debug print routines to direct
  97                   their output to the first serial port on these devices.
  98
  99         config DEBUG_CLPS711X_UART2
 100                 bool "Kernel low-level debugging messages via UART2"
 101                 depends on ARCH_CLPS711X
 102                 help
 103                   Say Y here if you want the debug print routines to direct
 104                   their output to the second serial port on these devices.
 105
 106         config DEBUG_DAVINCI_DA8XX_UART1
 107                 bool "Kernel low-level debugging on DaVinci DA8XX using UART1"
 108                 depends on ARCH_DAVINCI_DA8XX
 109                 help
 110                   Say Y here if you want the debug print routines to direct
 111                   their output to UART1 serial port on DaVinci DA8XX devices.
 112
 113         config DEBUG_DAVINCI_DA8XX_UART2
 114                 bool "Kernel low-level debugging on DaVinci DA8XX using UART2"
 115                 depends on ARCH_DAVINCI_DA8XX
 116                 help
 117                   Say Y here if you want the debug print routines to direct
 118                   their output to UART2 serial port on DaVinci DA8XX devices.
 119
 120         config DEBUG_DAVINCI_DMx_UART0
 121                 bool "Kernel low-level debugging on DaVinci DMx using UART0"
 122                 depends on ARCH_DAVINCI_DMx
 123                 help
 124                   Say Y here if you want the debug print routines to direct
 125                   their output to UART0 serial port on DaVinci DMx devices.
 126
 127         config DEBUG_DAVINCI_TNETV107X_UART1
 128                 bool "Kernel low-level debugging on DaVinci TNETV107x using UART1"
 129                 depends on ARCH_DAVINCI_TNETV107X
 130                 help
 131                   Say Y here if you want the debug print routines to direct
 132                   their output to UART1 serial port on DaVinci TNETV107X
 133                   devices.
 134
 135         config DEBUG_DC21285_PORT
 136                 bool "Kernel low-level debugging messages via footbridge serial port"
 137                 depends on FOOTBRIDGE
 138                 help
 139                   Say Y here if you want the debug print routines to direct
 140                   their output to the serial port in the DC21285 (Footbridge).
 141
 142         config DEBUG_FOOTBRIDGE_COM1
 143                 bool "Kernel low-level debugging messages via footbridge 8250 at PCI COM1"
 144                 depends on FOOTBRIDGE
 145                 help
 146                   Say Y here if you want the debug print routines to direct
 147                   their output to the 8250 at PCI COM1.
 148
 149         config DEBUG_HIGHBANK_UART
 150                 bool "Kernel low-level debugging messages via Highbank UART"
 151                 depends on ARCH_HIGHBANK
 152                 help
 153                   Say Y here if you want the debug print routines to direct
 154                   their output to the UART on Highbank based devices.
 155
 156         config DEBUG_IMX1_UART
 157                 bool "i.MX1 Debug UART"
 158                 depends on SOC_IMX1
 159                 help
 160                   Say Y here if you want kernel low-level debugging support
 161                   on i.MX1.
 162
 163         config DEBUG_IMX23_UART
 164                 bool "i.MX23 Debug UART"
 165                 depends on SOC_IMX23
 166                 help
 167                   Say Y here if you want kernel low-level debugging support
 168                   on i.MX23.
 169
 170         config DEBUG_IMX25_UART
 171                 bool "i.MX25 Debug UART"
 172                 depends on SOC_IMX25
 173                 help
 174                   Say Y here if you want kernel low-level debugging support
 175                   on i.MX25.
 176
 177         config DEBUG_IMX21_IMX27_UART
 178                 bool "i.MX21 and i.MX27 Debug UART"
 179                 depends on SOC_IMX21 || SOC_IMX27
 180                 help
 181                   Say Y here if you want kernel low-level debugging support
 182                   on i.MX21 or i.MX27.
 183
 184         config DEBUG_IMX28_UART
 185                 bool "i.MX28 Debug UART"
 186                 depends on SOC_IMX28
 187                 help
 188                   Say Y here if you want kernel low-level debugging support
 189                   on i.MX28.
 190
 191         config DEBUG_IMX31_IMX35_UART
 192                 bool "i.MX31 and i.MX35 Debug UART"
 193                 depends on SOC_IMX31 || SOC_IMX35
 194                 help
 195                   Say Y here if you want kernel low-level debugging support
 196                   on i.MX31 or i.MX35.
 197
 198         config DEBUG_IMX51_UART
 199                 bool "i.MX51 Debug UART"
 200                 depends on SOC_IMX51
 201                 help
 202                   Say Y here if you want kernel low-level debugging support
 203                   on i.MX51.
 204
 205         config DEBUG_IMX50_IMX53_UART
 206                 bool "i.MX50 and i.MX53 Debug UART"
 207                 depends on SOC_IMX50 || SOC_IMX53
 208                 help
 209                   Say Y here if you want kernel low-level debugging support
 210                   on i.MX50 or i.MX53.
 211
 212         config DEBUG_IMX6Q_UART2
 213                 bool "i.MX6Q Debug UART2"
 214                 depends on SOC_IMX6Q
 215                 help
 216                   Say Y here if you want kernel low-level debugging support
 217                   on i.MX6Q UART2. This is correct for e.g. the SabreLite
 218                   board.
 219
 220         config DEBUG_IMX6Q_UART4
 221                 bool "i.MX6Q Debug UART4"
 222                 depends on SOC_IMX6Q
 223                 help
 224                   Say Y here if you want kernel low-level debugging support
 225                   on i.MX6Q UART4.
 226
 227         config DEBUG_MMP_UART2
 228                 bool "Kernel low-level debugging message via MMP UART2"
 229                 depends on ARCH_MMP
 230                 help
 231                   Say Y here if you want kernel low-level debugging support
 232                   on MMP UART2.
 233
 234         config DEBUG_MMP_UART3
 235                 bool "Kernel low-level debugging message via MMP UART3"
 236                 depends on ARCH_MMP
 237                 help
 238                   Say Y here if you want kernel low-level debugging support
 239                   on MMP UART3.
 240
 241         config DEBUG_MSM_UART1
 242                 bool "Kernel low-level debugging messages via MSM UART1"
 243                 depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
 244                 help
 245                   Say Y here if you want the debug print routines to direct
 246                   their output to the first serial port on MSM devices.
 247
 248         config DEBUG_MSM_UART2
 249                 bool "Kernel low-level debugging messages via MSM UART2"
 250                 depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
 251                 help
 252                   Say Y here if you want the debug print routines to direct
 253                   their output to the second serial port on MSM devices.
 254
 255         config DEBUG_MSM_UART3
 256                 bool "Kernel low-level debugging messages via MSM UART3"
 257                 depends on ARCH_MSM7X00A || ARCH_MSM7X30 || ARCH_QSD8X50
 258                 help
 259                   Say Y here if you want the debug print routines to direct
 260                   their output to the third serial port on MSM devices.
 261
 262         config DEBUG_MSM8660_UART
 263                 bool "Kernel low-level debugging messages via MSM 8660 UART"
 264                 depends on ARCH_MSM8X60
 265                 select MSM_HAS_DEBUG_UART_HS
 266                 help
 267                   Say Y here if you want the debug print routines to direct
 268                   their output to the serial port on MSM 8660 devices.
 269
 270         config DEBUG_MSM8960_UART
 271                 bool "Kernel low-level debugging messages via MSM 8960 UART"
 272                 depends on ARCH_MSM8960
 273                 select MSM_HAS_DEBUG_UART_HS
 274                 help
 275                   Say Y here if you want the debug print routines to direct
 276                   their output to the serial port on MSM 8960 devices.
 277
 278         config DEBUG_MVEBU_UART
 279                 bool "Kernel low-level debugging messages via MVEBU UART"
 280                 depends on ARCH_MVEBU
 281                 help
 282                   Say Y here if you want kernel low-level debugging support
 283                   on MVEBU based platforms.
 284
 285         config DEBUG_PICOXCELL_UART
 286                 depends on ARCH_PICOXCELL
 287                 bool "Use PicoXcell UART for low-level debug"
 288                 help
 289                   Say Y here if you want kernel low-level debugging support
 290                   on PicoXcell based platforms.
 291
 292         config DEBUG_REALVIEW_STD_PORT
 293                 bool "RealView Default UART"
 294                 depends on ARCH_REALVIEW
 295                 help
 296                   Say Y here if you want the debug print routines to direct
 297                   their output to the serial port on RealView EB, PB11MP, PBA8
 298                   and PBX platforms.
 299
 300         config DEBUG_REALVIEW_PB1176_PORT
 301                 bool "RealView PB1176 UART"
 302                 depends on MACH_REALVIEW_PB1176
 303                 help
 304                   Say Y here if you want the debug print routines to direct
 305                   their output to the standard serial port on the RealView
 306                   PB1176 platform.
 307
 308         config DEBUG_S3C_UART0
 309                 depends on PLAT_SAMSUNG
 310                 bool "Use S3C UART 0 for low-level debug"
 311                 help
 312                   Say Y here if you want the debug print routines to direct
 313                   their output to UART 0. The port must have been initialised
 314                   by the boot-loader before use.
 315
 316                   The uncompressor code port configuration is now handled
 317                   by CONFIG_S3C_LOWLEVEL_UART_PORT.
 318
 319         config DEBUG_S3C_UART1
 320                 depends on PLAT_SAMSUNG
 321                 bool "Use S3C UART 1 for low-level debug"
 322                 help
 323                   Say Y here if you want the debug print routines to direct
 324                   their output to UART 1. The port must have been initialised
 325                   by the boot-loader before use.
 326
 327                   The uncompressor code port configuration is now handled
 328                   by CONFIG_S3C_LOWLEVEL_UART_PORT.
 329
 330         config DEBUG_S3C_UART2
 331                 depends on PLAT_SAMSUNG
 332                 bool "Use S3C UART 2 for low-level debug"
 333                 help
 334                   Say Y here if you want the debug print routines to direct
 335                   their output to UART 2. The port must have been initialised
 336                   by the boot-loader before use.
 337
 338                   The uncompressor code port configuration is now handled
 339                   by CONFIG_S3C_LOWLEVEL_UART_PORT.
 340
 341         config DEBUG_SOCFPGA_UART
 342                 depends on ARCH_SOCFPGA
 343                 bool "Use SOCFPGA UART for low-level debug"
 344                 help
 345                   Say Y here if you want kernel low-level debugging support
 346                   on SOCFPGA based platforms.
 347
 348         config DEBUG_VEXPRESS_UART0_DETECT
 349                 bool "Autodetect UART0 on Versatile Express Cortex-A core tiles"
 350                 depends on ARCH_VEXPRESS && CPU_CP15_MMU
 351                 help
 352                   This option enables a simple heuristic which tries to determine
 353                   the motherboard's memory map variant (original or RS1) and then
 354                   choose the relevant UART0 base address.
 355
 356                   Note that this will only work with standard A-class core tiles,
 357                   and may fail with non-standard SMM or custom software models.
 358
 359         config DEBUG_VEXPRESS_UART0_CA9
 360                 bool "Use PL011 UART0 at 0x10009000 (V2P-CA9 core tile)"
 361                 depends on ARCH_VEXPRESS
 362                 help
 363                   This option selects UART0 at 0x10009000. Except for custom models,
 364                   this applies only to the V2P-CA9 tile.
 365
 366         config DEBUG_VEXPRESS_UART0_RS1
 367                 bool "Use PL011 UART0 at 0x1c090000 (RS1 complaint tiles)"
 368                 depends on ARCH_VEXPRESS
 369                 help
 370                   This option selects UART0 at 0x1c090000. This applies to most
 371                   of the tiles using the RS1 memory map, including all new A-class
 372                   core tiles, FPGA-based SMMs and software models.
 373
 374         config DEBUG_LL_UART_NONE
 375                 bool "No low-level debugging UART"
 376                 depends on !ARCH_MULTIPLATFORM
 377                 help
 378                   Say Y here if your platform doesn't provide a UART option
 379                   below. This relies on your platform choosing the right UART
 380                   definition internally in order for low-level debugging to
 381                   work.
 382
 383         config DEBUG_ICEDCC
 384                 bool "Kernel low-level debugging via EmbeddedICE DCC channel"
 385                 help
 386                   Say Y here if you want the debug print routines to direct
 387                   their output to the EmbeddedICE macrocell's DCC channel using
 388                   co-processor 14. This is known to work on the ARM9 style ICE
 389                   channel and on the XScale with the PEEDI.
 390
 391                   Note that the system will appear to hang during boot if there
 392                   is nothing connected to read from the DCC.
 393
 394         config DEBUG_SEMIHOSTING
 395                 bool "Kernel low-level debug output via semihosting I/O"
 396                 help
 397                   Semihosting enables code running on an ARM target to use
 398                   the I/O facilities on a host debugger/emulator through a
 399                   simple SVC call. The host debugger or emulator must have
 400                   semihosting enabled for the special svc call to be trapped
 401                   otherwise the kernel will crash.
 402
 403                   This is known to work with OpenOCD, as well as
 404                   ARM's Fast Models, or any other controlling environment
 405                   that implements semihosting.
 406
 407                   For more details about semihosting, please see
 408                   chapter 8 of DUI0203I_rvct_developer_guide.pdf from ARM Ltd.
 409
 410 endchoice
 411
 412 config DEBUG_LL_INCLUDE
 413         string
 414         default "debug/icedcc.S" if DEBUG_ICEDCC
 415         default "debug/highbank.S" if DEBUG_HIGHBANK_UART
 416         default "debug/mvebu.S" if DEBUG_MVEBU_UART
 417         default "debug/picoxcell.S" if DEBUG_PICOXCELL_UART
 418         default "debug/socfpga.S" if DEBUG_SOCFPGA_UART
 419         default "debug/vexpress.S" if DEBUG_VEXPRESS_UART0_DETECT || \
 420                 DEBUG_VEXPRESS_UART0_CA9 || DEBUG_VEXPRESS_UART0_RS1
 421         default "mach/debug-macro.S"
 422
 423 config EARLY_PRINTK
 424         bool "Early printk"
 425         depends on DEBUG_LL
 426         help
 427           Say Y here if you want to have an early console using the
 428           kernel low-level debugging functions. Add earlyprintk to your
 429           kernel parameters to enable this console.
 430
 431 config OC_ETM
 432         bool "On-chip ETM and ETB"
 433         depends on ARM_AMBA
 434         help
 435           Enables the on-chip embedded trace macrocell and embedded trace
 436           buffer driver that will allow you to collect traces of the
 437           kernel code.
 438
 439 config ARM_KPROBES_TEST
 440         tristate "Kprobes test module"
 441         depends on KPROBES && MODULES
 442         help
 443           Perform tests of kprobes API and instruction set simulation.
 444
 445 config PID_IN_CONTEXTIDR
 446         bool "Write the current PID to the CONTEXTIDR register"
 447         depends on CPU_COPY_V6
 448         help
 449           Enabling this option causes the kernel to write the current PID to
 450           the PROCID field of the CONTEXTIDR register, at the expense of some
 451           additional instructions during context switch. Say Y here only if you
 452           are planning to use hardware trace tools with this kernel.
 453
 454 endmenu