arch/arm/Kconfig.debug

   1 menu "Kernel hacking"
   2
   3 source "lib/Kconfig.debug"
   4
   5 # RMK wants arm kernels compiled with frame pointers or stack unwinding.
   6 # If you know what you are doing and are willing to live without stack
   7 # traces, you can get a slightly smaller kernel by setting this option to
   8 # n, but then RMK will have to kill you ;).
   9 config FRAME_POINTER
  10         bool
  11         depends on !THUMB2_KERNEL
  12         default y if !ARM_UNWIND
  13         help
  14           If you say N here, the resulting kernel will be slightly smaller and
  15           faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,
  16           when a problem occurs with the kernel, the information that is
  17           reported is severely limited.
  18
  19 config ARM_UNWIND
  20         bool "Enable stack unwinding support"
  21         depends on AEABI && EXPERIMENTAL
  22         default y
  23         help
  24           This option enables stack unwinding support in the kernel
  25           using the information automatically generated by the
  26           compiler. The resulting kernel image is slightly bigger but
  27           the performance is not affected. Currently, this feature
  28           only works with EABI compilers. If unsure say Y.
  29
  30 config DEBUG_USER
  31         bool "Verbose user fault messages"
  32         help
  33           When a user program crashes due to an exception, the kernel can
  34           print a brief message explaining what the problem was. This is
  35           sometimes helpful for debugging but serves no purpose on a
  36           production system. Most people should say N here.
  37
  38           In addition, you need to pass user_debug=N on the kernel command
  39           line to enable this feature.  N consists of the sum of:
  40
  41               1 - undefined instruction events
  42               2 - system calls
  43               4 - invalid data aborts
  44               8 - SIGSEGV faults
  45              16 - SIGBUS faults
  46
  47 config DEBUG_ERRORS
  48         bool "Verbose kernel error messages"
  49         depends on DEBUG_KERNEL
  50         help
  51           This option controls verbose debugging information which can be
  52           printed when the kernel detects an internal error. This debugging
  53           information is useful to kernel hackers when tracking down problems,
  54           but mostly meaningless to other people. It's safe to say Y unless
  55           you are concerned with the code size or don't want to see these
  56           messages.
  57
  58 config DEBUG_STACK_USAGE
  59         bool "Enable stack utilization instrumentation"
  60         depends on DEBUG_KERNEL
  61         help
  62           Enables the display of the minimum amount of free stack which each
  63           task has ever had available in the sysrq-T output.
  64
  65 # These options are only for real kernel hackers who want to get their hands dirty.
  66 config DEBUG_LL
  67         bool "Kernel low-level debugging functions"
  68         depends on DEBUG_KERNEL
  69         help
  70           Say Y here to include definitions of printascii, printch, printhex
  71           in the kernel.  This is helpful if you are debugging code that
  72           executes before the console is initialized.
  73
  74 config EARLY_PRINTK
  75         bool "Early printk"
  76         depends on DEBUG_LL
  77         help
  78           Say Y here if you want to have an early console using the
  79           kernel low-level debugging functions. Add earlyprintk to your
  80           kernel parameters to enable this console.
  81
  82 config DEBUG_ICEDCC
  83         bool "Kernel low-level debugging via EmbeddedICE DCC channel"
  84         depends on DEBUG_LL
  85         help
  86           Say Y here if you want the debug print routines to direct their
  87           output to the EmbeddedICE macrocell's DCC channel using
  88           co-processor 14. This is known to work on the ARM9 style ICE
  89           channel and on the XScale with the PEEDI.
  90
  91           It does include a timeout to ensure that the system does not
  92           totally freeze when there is nothing connected to read.
  93
  94 config OC_ETM
  95         bool "On-chip ETM and ETB"
  96         select ARM_AMBA
  97         help
  98           Enables the on-chip embedded trace macrocell and embedded trace
  99           buffer driver that will allow you to collect traces of the
 100           kernel code.
 101
 102 config DEBUG_DC21285_PORT
 103         bool "Kernel low-level debugging messages via footbridge serial port"
 104         depends on DEBUG_LL && FOOTBRIDGE
 105         help
 106           Say Y here if you want the debug print routines to direct their
 107           output to the serial port in the DC21285 (Footbridge). Saying N
 108           will cause the debug messages to appear on the first 16550
 109           serial port.
 110
 111 config DEBUG_CLPS711X_UART2
 112         bool "Kernel low-level debugging messages via UART2"
 113         depends on DEBUG_LL && ARCH_CLPS711X
 114         help
 115           Say Y here if you want the debug print routines to direct their
 116           output to the second serial port on these devices.  Saying N will
 117           cause the debug messages to appear on the first serial port.
 118
 119 config DEBUG_S3C_UART
 120         depends on PLAT_S3C
 121         int "S3C UART to use for low-level debug"
 122         default "0"
 123         help
 124           Choice for UART for kernel low-level using S3C UARTS,
 125           should be between zero and two. The port must have been
 126           initialised by the boot-loader before use.
 127
 128           The uncompressor code port configuration is now handled
 129           by CONFIG_S3C_LOWLEVEL_UART_PORT.
 130
 131 endmenu