| 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. | 
 |  | 
 | 	config DEBUG_HIGHBANK_UART | 
 | 		bool "Kernel low-level debugging messages via Highbank UART" | 
 | 		depends on ARCH_HIGHBANK | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to the UART on Highbank based devices. | 
 |  | 
 | 	config DEBUG_IMX1_UART | 
 | 		bool "i.MX1 Debug UART" | 
 | 		depends on SOC_IMX1 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX1. | 
 |  | 
 | 	config DEBUG_IMX23_UART | 
 | 		bool "i.MX23 Debug UART" | 
 | 		depends on SOC_IMX23 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX23. | 
 |  | 
 | 	config DEBUG_IMX25_UART | 
 | 		bool "i.MX25 Debug UART" | 
 | 		depends on SOC_IMX25 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX25. | 
 |  | 
 | 	config DEBUG_IMX21_IMX27_UART | 
 | 		bool "i.MX21 and i.MX27 Debug UART" | 
 | 		depends on SOC_IMX21 || SOC_IMX27 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX21 or i.MX27. | 
 |  | 
 | 	config DEBUG_IMX28_UART | 
 | 		bool "i.MX28 Debug UART" | 
 | 		depends on SOC_IMX28 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX28. | 
 |  | 
 | 	config DEBUG_IMX31_IMX35_UART | 
 | 		bool "i.MX31 and i.MX35 Debug UART" | 
 | 		depends on SOC_IMX31 || SOC_IMX35 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX31 or i.MX35. | 
 |  | 
 | 	config DEBUG_IMX51_UART | 
 | 		bool "i.MX51 Debug UART" | 
 | 		depends on SOC_IMX51 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX51. | 
 |  | 
 | 	config DEBUG_IMX50_IMX53_UART | 
 | 		bool "i.MX50 and i.MX53 Debug UART" | 
 | 		depends on SOC_IMX50 || SOC_IMX53 | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX50 or i.MX53. | 
 |  | 
 | 	config DEBUG_IMX6Q_UART | 
 | 		bool "i.MX6Q Debug UART" | 
 | 		depends on SOC_IMX6Q | 
 | 		help | 
 | 		  Say Y here if you want kernel low-level debugging support | 
 | 		  on i.MX6Q. | 
 |  | 
 | 	config DEBUG_S3C_UART0 | 
 | 		depends on PLAT_SAMSUNG | 
 | 		bool "Use S3C UART 0 for low-level debug" | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to UART 0. 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 DEBUG_S3C_UART1 | 
 | 		depends on PLAT_SAMSUNG | 
 | 		bool "Use S3C UART 1 for low-level debug" | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to UART 1. 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 DEBUG_S3C_UART2 | 
 | 		depends on PLAT_SAMSUNG | 
 | 		bool "Use S3C UART 2 for low-level debug" | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to UART 2. 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 DEBUG_REALVIEW_STD_PORT | 
 | 		bool "RealView Default UART" | 
 | 		depends on ARCH_REALVIEW | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to the serial port on RealView EB, PB11MP, PBA8 | 
 | 		  and PBX platforms. | 
 |  | 
 | 	config DEBUG_REALVIEW_PB1176_PORT | 
 | 		bool "RealView PB1176 UART" | 
 | 		depends on MACH_REALVIEW_PB1176 | 
 | 		help | 
 | 		  Say Y here if you want the debug print routines to direct | 
 | 		  their output to the standard serial port on the RealView | 
 | 		  PB1176 platform. | 
 |  | 
 | 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 ARM_KPROBES_TEST | 
 | 	tristate "Kprobes test module" | 
 | 	depends on KPROBES && MODULES | 
 | 	help | 
 | 	  Perform tests of kprobes API and instruction set simulation. | 
 |  | 
 | endmenu |