[deliverable/linux.git] / arch / arm / Kconfig.debug

menu "Kernel hacking"

source "lib/Kconfig.debug"

config STRICT_DEVMEM
	bool "Filter access to /dev/mem"
	depends on MMU
	---help---
	  If this option is disabled, you allow userspace (root) access to all
	  of memory, including kernel and userspace memory. Accidental
	  access to this is obviously disastrous, but specific access can
	  be used by people debugging the kernel.

	  If this option is switched on, the /dev/mem file only allows
	  userspace access to memory mapped peripherals.

          If in doubt, say Y.

# RMK wants arm kernels compiled with frame pointers or stack unwinding.
# If you know what you are doing and are willing to live without stack
# traces, you can get a slightly smaller kernel by setting this option to
# n, but then RMK will have to kill you ;).
config FRAME_POINTER
	bool
	depends on !THUMB2_KERNEL
	default y if !ARM_UNWIND || FUNCTION_GRAPH_TRACER
	help
	  If you say N here, the resulting kernel will be slightly smaller and
	  faster. However, if neither FRAME_POINTER nor ARM_UNWIND are enabled,
	  when a problem occurs with the kernel, the information that is
	  reported is severely limited.

config ARM_UNWIND
	bool "Enable stack unwinding support (EXPERIMENTAL)"
	depends on AEABI && EXPERIMENTAL
	default y
	help
	  This option enables stack unwinding support in the kernel
	  using the information automatically generated by the
	  compiler. The resulting kernel image is slightly bigger but
	  the performance is not affected. Currently, this feature
	  only works with EABI compilers. If unsure say Y.

config OLD_MCOUNT
	bool
	depends on FUNCTION_TRACER && FRAME_POINTER
	default y

config DEBUG_USER
	bool "Verbose user fault messages"
	help
	  When a user program crashes due to an exception, the kernel can
	  print a brief message explaining what the problem was. This is
	  sometimes helpful for debugging but serves no purpose on a
	  production system. Most people should say N here.

	  In addition, you need to pass user_debug=N on the kernel command
	  line to enable this feature.  N consists of the sum of:

	      1 - undefined instruction events
	      2 - system calls
	      4 - invalid data aborts
	      8 - SIGSEGV faults
	     16 - SIGBUS faults

# These options are only for real kernel hackers who want to get their hands dirty.
config DEBUG_LL
	bool "Kernel low-level debugging functions (read help!)"
	depends on DEBUG_KERNEL
	help
	  Say Y here to include definitions of printascii, printch, printhex
	  in the kernel.  This is helpful if you are debugging code that
	  executes before the console is initialized.

	  Note that selecting this option will limit the kernel to a single
	  UART definition, as specified below. Attempting to boot the kernel
	  image on a different platform *will not work*, so this option should
	  not be enabled for kernels that are intended to be portable.

choice
	prompt "Kernel low-level debugging port"
	depends on DEBUG_LL

	config DEBUG_LL_UART_NONE
		bool "No low-level debugging UART"
		help
		  Say Y here if your platform doesn't provide a UART option
		  below. This relies on your platform choosing the right UART
		  definition internally in order for low-level debugging to
		  work.

	config DEBUG_ICEDCC
		bool "Kernel low-level debugging via EmbeddedICE DCC channel"
		help
		  Say Y here if you want the debug print routines to direct
		  their output to the EmbeddedICE macrocell's DCC channel using
		  co-processor 14. This is known to work on the ARM9 style ICE
		  channel and on the XScale with the PEEDI.

		  Note that the system will appear to hang during boot if there
		  is nothing connected to read from the DCC.

	config DEBUG_FOOTBRIDGE_COM1
		bool "Kernel low-level debugging messages via footbridge 8250 at PCI COM1"
		depends on FOOTBRIDGE
		help
		  Say Y here if you want the debug print routines to direct
		  their output to the 8250 at PCI COM1.

	config DEBUG_DC21285_PORT
		bool "Kernel low-level debugging messages via footbridge serial port"
		depends on FOOTBRIDGE
		help
		  Say Y here if you want the debug print routines to direct
		  their output to the serial port in the DC21285 (Footbridge).

	config DEBUG_CLPS711X_UART1
		bool "Kernel low-level debugging messages via UART1"
		depends on ARCH_CLPS711X
		help
		  Say Y here if you want the debug print routines to direct
		  their output to the first serial port on these devices.

	config DEBUG_CLPS711X_UART2
		bool "Kernel low-level debugging messages via UART2"
		depends on ARCH_CLPS711X
		help
		  Say Y here if you want the debug print routines to direct
		  their output to the second serial port on these devices.

endchoice

config EARLY_PRINTK
	bool "Early printk"
	depends on DEBUG_LL
	help
	  Say Y here if you want to have an early console using the
	  kernel low-level debugging functions. Add earlyprintk to your
	  kernel parameters to enable this console.

config OC_ETM
	bool "On-chip ETM and ETB"
	depends on ARM_AMBA
	help
	  Enables the on-chip embedded trace macrocell and embedded trace
	  buffer driver that will allow you to collect traces of the
	  kernel code.

config DEBUG_S3C_UART
	depends on PLAT_SAMSUNG
	int "S3C UART to use for low-level debug"
	default "0"
	help
	  Choice for UART for kernel low-level using S3C UARTS,
	  should be between zero and two. The port must have been
	  initialised by the boot-loader before use.

	  The uncompressor code port configuration is now handled
	  by CONFIG_S3C_LOWLEVEL_UART_PORT.

config ARM_KPROBES_TEST
	tristate "Kprobes test module"
	depends on KPROBES && MODULES
	help
	  Perform tests of kprobes API and instruction set simulation.

endmenu
Commit	Line	Data
1da177e4 LT	1	menu "Kernel hacking"
	2
	3	source "lib/Kconfig.debug"
	4
087aaffc NP	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
adf8b37b	19	# RMK wants arm kernels compiled with frame pointers or stack unwinding.
1da177e4 LT	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
16c79651	25	depends on !THUMB2_KERNEL
0e341af8	26	default y if !ARM_UNWIND \|\| FUNCTION_GRAPH_TRACER
1da177e4 LT	27	help
1da177e4 LT	28	If you say N here, the resulting kernel will be slightly smaller and
adf8b37b CM	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
4a50bfe3	34	bool "Enable stack unwinding support (EXPERIMENTAL)"
adf8b37b CM	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.
1da177e4	43
09bfafac RV	44	config OLD_MCOUNT
	45	bool
	46	depends on FUNCTION_TRACER && FRAME_POINTER
	47	default y
	48
1da177e4 LT	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
1da177e4 LT	66	# These options are only for real kernel hackers who want to get their hands dirty.
1da177e4 LT	67	config DEBUG_LL
4f5ef922	68	bool "Kernel low-level debugging functions (read help!)"
1da177e4 LT	69	depends on DEBUG_KERNEL
1da177e4 LT	70	help
35efb606	71	Say Y here to include definitions of printascii, printch, printhex
1da177e4 LT	72	in the kernel. This is helpful if you are debugging code that
	73	executes before the console is initialized.
	74
4f5ef922 WD	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
17916b28 WD	80	choice
	81	prompt "Kernel low-level debugging port"
	82	depends on DEBUG_LL
	83
f73765fc WD	84	config DEBUG_LL_UART_NONE
	85	bool "No low-level debugging UART"
	86	help
	87	Say Y here if your platform doesn't provide a UART option
	88	below. This relies on your platform choosing the right UART
	89	definition internally in order for low-level debugging to
	90	work.
	91
6996f425 SB	92	config DEBUG_ICEDCC
	93	bool "Kernel low-level debugging via EmbeddedICE DCC channel"
	94	help
	95	Say Y here if you want the debug print routines to direct
	96	their output to the EmbeddedICE macrocell's DCC channel using
	97	co-processor 14. This is known to work on the ARM9 style ICE
	98	channel and on the XScale with the PEEDI.
	99
f73765fc WD	100	Note that the system will appear to hang during boot if there
f73765fc WD	101	is nothing connected to read from the DCC.
164acf96 SB	102
	103	config DEBUG_FOOTBRIDGE_COM1
	104	bool "Kernel low-level debugging messages via footbridge 8250 at PCI COM1"
	105	depends on FOOTBRIDGE
	106	help
	107	Say Y here if you want the debug print routines to direct
	108	their output to the 8250 at PCI COM1.
	109
17916b28 WD	110	config DEBUG_DC21285_PORT
	111	bool "Kernel low-level debugging messages via footbridge serial port"
	112	depends on FOOTBRIDGE
	113	help
	114	Say Y here if you want the debug print routines to direct
	115	their output to the serial port in the DC21285 (Footbridge).
164acf96 SB	116
	117	config DEBUG_CLPS711X_UART1
	118	bool "Kernel low-level debugging messages via UART1"
	119	depends on ARCH_CLPS711X
	120	help
	121	Say Y here if you want the debug print routines to direct
	122	their output to the first serial port on these devices.
17916b28 WD	123
	124	config DEBUG_CLPS711X_UART2
	125	bool "Kernel low-level debugging messages via UART2"
	126	depends on ARCH_CLPS711X
	127	help
	128	Say Y here if you want the debug print routines to direct
	129	their output to the second serial port on these devices.
17916b28 WD	130
	131	endchoice
	132
93fd03a8 CM	133	config EARLY_PRINTK
	134	bool "Early printk"
	135	depends on DEBUG_LL
	136	help
	137	Say Y here if you want to have an early console using the
	138	kernel low-level debugging functions. Add earlyprintk to your
	139	kernel parameters to enable this console.
	140
c5d6c770 AS	141	config OC_ETM
c5d6c770 AS	142	bool "On-chip ETM and ETB"
53eebb0d	143	depends on ARM_AMBA
c5d6c770 AS	144	help
	145	Enables the on-chip embedded trace macrocell and embedded trace
	146	buffer driver that will allow you to collect traces of the
	147	kernel code.
	148
3ec20520	149	config DEBUG_S3C_UART
89f1fa08	150	depends on PLAT_SAMSUNG
3ec20520	151	int "S3C UART to use for low-level debug"
1da177e4 LT	152	default "0"
1da177e4 LT	153	help
3ec20520	154	Choice for UART for kernel low-level using S3C UARTS,
1da177e4	155	should be between zero and two. The port must have been
c41045a4	156	initialised by the boot-loader before use.
1da177e4 LT	157
1da177e4 LT	158	The uncompressor code port configuration is now handled
c7657846	159	by CONFIG_S3C_LOWLEVEL_UART_PORT.
1da177e4	160
4189bc71 JM	161	config ARM_KPROBES_TEST
	162	tristate "Kprobes test module"
	163	depends on KPROBES && MODULES
	164	help
	165	Perform tests of kprobes API and instruction set simulation.
	166
1da177e4	167	endmenu