path: root/arch/arm/Kconfig.debug

menu "Kernel hacking"

source "lib/Kconfig.debug"

config ARM_PTDUMP
	bool "Export kernel pagetable layout to userspace via debugfs"
	depends on DEBUG_KERNEL
	select DEBUG_FS
	---help---
	  Say Y here if you want to show the kernel pagetable layout in a
	  debugfs file. This information is only useful for kernel developers
	  who are working in architecture specific areas of the kernel.
	  It is probably not a good idea to enable this feature in a production
	  kernel.
	  If in doubt, say "N"

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
	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_ALPINE_UART0
		bool "Kernel low-level debugging messages via Alpine UART0"
		depends on ARCH_ALPINE
		select DEBUG_UART_8250
		help
		  Say Y here if you want kernel low-level debugging support
		  on Alpine based platforms.

	config DEBUG_ASM9260_UART
		bool "Kernel low-level debugging via asm9260 UART"
		depends on MACH_ASM9260
		help
		  Say Y here if you want the debug print routines to direct
		  their output to an UART or USART port on asm9260 based
		  machines.

		    DEBUG_UART_PHYS | DEBUG_UART_VIRT

		    0x80000000      | 0xf0000000     | UART0
		    0x80004000      | 0xf0004000     | UART1
		    0x80008000      | 0xf0008000     | UART2
		    0x8000c000      | 0xf000c000     | UART3
		    0x80010000      | 0xf0010000     | UART4
		    0x80014000      | 0xf0014000     | UART5
		    0x80018000      | 0xf0018000     | UART6
		    0x8001c000      | 0xf001c000     | UART7
		    0x80020000      | 0xf0020000     | UART8
		    0x80024000      | 0xf0024000     | UART9

	config AT91_DEBUG_LL_DBGU0
		bool "Kernel low-level debugging on rm9200, 9260/9g20, 9261/9g10, 9rl, 9x5, 9n12"
		select DEBUG_AT91_UART
		depends on ARCH_AT91
		depends on SOC_AT91RM9200 || SOC_AT91SAM9

	config AT91_DEBUG_LL_DBGU1
		bool "Kernel low-level debugging on 9263, 9g45 and sama5d3"
		select DEBUG_AT91_UART
		depends on ARCH_AT91
		depends on SOC_AT91SAM9 || SOC_SAMA5

	config AT91_DEBUG_LL_DBGU2
		bool "Kernel low-level debugging on sama5d4"
		select DEBUG_AT91_UART
		depends on ARCH_AT91
		depends on SOC_SAMA5

	config DEBUG_BCM2835
		bool "Kernel low-level debugging on BCM2835 PL011 UART"
		depends on ARCH_BCM2835
		select DEBUG_UART_PL01X

	config DEBUG_BCM_5301X
		bool "K