xref: /linux/arch/arm/Kconfig.debug (revision 3ec20520ddfb654b1e60f51ff5e4769afde51b36)
11da177e4SLinus Torvaldsmenu "Kernel hacking"
21da177e4SLinus Torvalds
31da177e4SLinus Torvaldssource "lib/Kconfig.debug"
41da177e4SLinus Torvalds
51da177e4SLinus Torvalds# RMK wants arm kernels compiled with frame pointers so hardwire this to y.
61da177e4SLinus Torvalds# If you know what you are doing and are willing to live without stack
71da177e4SLinus Torvalds# traces, you can get a slightly smaller kernel by setting this option to
81da177e4SLinus Torvalds# n, but then RMK will have to kill you ;).
91da177e4SLinus Torvaldsconfig FRAME_POINTER
101da177e4SLinus Torvalds	bool
111da177e4SLinus Torvalds	default y
121da177e4SLinus Torvalds	help
131da177e4SLinus Torvalds	  If you say N here, the resulting kernel will be slightly smaller and
141da177e4SLinus Torvalds	  faster. However, when a problem occurs with the kernel, the
151da177e4SLinus Torvalds	  information that is reported is severely limited. Most people
161da177e4SLinus Torvalds	  should say Y here.
171da177e4SLinus Torvalds
181da177e4SLinus Torvaldsconfig DEBUG_USER
191da177e4SLinus Torvalds	bool "Verbose user fault messages"
201da177e4SLinus Torvalds	help
211da177e4SLinus Torvalds	  When a user program crashes due to an exception, the kernel can
221da177e4SLinus Torvalds	  print a brief message explaining what the problem was. This is
231da177e4SLinus Torvalds	  sometimes helpful for debugging but serves no purpose on a
241da177e4SLinus Torvalds	  production system. Most people should say N here.
251da177e4SLinus Torvalds
261da177e4SLinus Torvalds	  In addition, you need to pass user_debug=N on the kernel command
271da177e4SLinus Torvalds	  line to enable this feature.  N consists of the sum of:
281da177e4SLinus Torvalds
291da177e4SLinus Torvalds	      1 - undefined instruction events
301da177e4SLinus Torvalds	      2 - system calls
311da177e4SLinus Torvalds	      4 - invalid data aborts
321da177e4SLinus Torvalds	      8 - SIGSEGV faults
331da177e4SLinus Torvalds	     16 - SIGBUS faults
341da177e4SLinus Torvalds
351da177e4SLinus Torvaldsconfig DEBUG_ERRORS
361da177e4SLinus Torvalds	bool "Verbose kernel error messages"
371da177e4SLinus Torvalds	depends on DEBUG_KERNEL
381da177e4SLinus Torvalds	help
391da177e4SLinus Torvalds	  This option controls verbose debugging information which can be
401da177e4SLinus Torvalds	  printed when the kernel detects an internal error. This debugging
411da177e4SLinus Torvalds	  information is useful to kernel hackers when tracking down problems,
421da177e4SLinus Torvalds	  but mostly meaningless to other people. It's safe to say Y unless
431da177e4SLinus Torvalds	  you are concerned with the code size or don't want to see these
441da177e4SLinus Torvalds	  messages.
451da177e4SLinus Torvalds
461da177e4SLinus Torvalds
471da177e4SLinus Torvalds# These options are only for real kernel hackers who want to get their hands dirty.
481da177e4SLinus Torvaldsconfig DEBUG_LL
491da177e4SLinus Torvalds	bool "Kernel low-level debugging functions"
501da177e4SLinus Torvalds	depends on DEBUG_KERNEL
511da177e4SLinus Torvalds	help
5235efb606SRussell King	  Say Y here to include definitions of printascii, printch, printhex
531da177e4SLinus Torvalds	  in the kernel.  This is helpful if you are debugging code that
541da177e4SLinus Torvalds	  executes before the console is initialized.
551da177e4SLinus Torvalds
561da177e4SLinus Torvaldsconfig DEBUG_ICEDCC
571da177e4SLinus Torvalds	bool "Kernel low-level debugging via EmbeddedICE DCC channel"
581da177e4SLinus Torvalds	depends on DEBUG_LL
591da177e4SLinus Torvalds	help
601da177e4SLinus Torvalds	  Say Y here if you want the debug print routines to direct their
611da177e4SLinus Torvalds	  output to the EmbeddedICE macrocell's DCC channel using
621da177e4SLinus Torvalds	  co-processor 14. This is known to work on the ARM9 style ICE
631da177e4SLinus Torvalds	  channel.
641da177e4SLinus Torvalds
651da177e4SLinus Torvalds	  It does include a timeout to ensure that the system does not
661da177e4SLinus Torvalds	  totally freeze when there is nothing connected to read.
671da177e4SLinus Torvalds
681da177e4SLinus Torvaldsconfig DEBUG_DC21285_PORT
691da177e4SLinus Torvalds	bool "Kernel low-level debugging messages via footbridge serial port"
701da177e4SLinus Torvalds	depends on DEBUG_LL && FOOTBRIDGE
711da177e4SLinus Torvalds	help
721da177e4SLinus Torvalds	  Say Y here if you want the debug print routines to direct their
731da177e4SLinus Torvalds	  output to the serial port in the DC21285 (Footbridge). Saying N
741da177e4SLinus Torvalds	  will cause the debug messages to appear on the first 16550
751da177e4SLinus Torvalds	  serial port.
761da177e4SLinus Torvalds
771da177e4SLinus Torvaldsconfig DEBUG_CLPS711X_UART2
781da177e4SLinus Torvalds	bool "Kernel low-level debugging messages via UART2"
791da177e4SLinus Torvalds	depends on DEBUG_LL && ARCH_CLPS711X
801da177e4SLinus Torvalds	help
811da177e4SLinus Torvalds	  Say Y here if you want the debug print routines to direct their
821da177e4SLinus Torvalds	  output to the second serial port on these devices.  Saying N will
831da177e4SLinus Torvalds	  cause the debug messages to appear on the first serial port.
841da177e4SLinus Torvalds
85*3ec20520SBen Dooksconfig DEBUG_S3C_PORT
86*3ec20520SBen Dooks	depends on DEBUG_LL && PLAT_S3C
87*3ec20520SBen Dooks	bool "Kernel low-level debugging messages via S3C UART"
881da177e4SLinus Torvalds	help
891da177e4SLinus Torvalds	  Say Y here if you want debug print routines to go to one of the
90*3ec20520SBen Dooks	  S3C internal UARTs. The chosen UART must have been configured
911da177e4SLinus Torvalds	  before it is used.
921da177e4SLinus Torvalds
93*3ec20520SBen Dooksconfig DEBUG_S3C_UART
94*3ec20520SBen Dooks	depends on PLAT_S3C
95*3ec20520SBen Dooks	int "S3C UART to use for low-level debug"
961da177e4SLinus Torvalds	default "0"
971da177e4SLinus Torvalds	help
98*3ec20520SBen Dooks	  Choice for UART for kernel low-level using S3C UARTS,
991da177e4SLinus Torvalds	  should be between zero and two. The port must have been
100c41045a4SEgry Gabor	  initialised by the boot-loader before use.
1011da177e4SLinus Torvalds
1021da177e4SLinus Torvalds	  The uncompressor code port configuration is now handled
103c7657846SBen Dooks	  by CONFIG_S3C_LOWLEVEL_UART_PORT.
1041da177e4SLinus Torvalds
1051da177e4SLinus Torvaldsendmenu
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