xref: /openbmc/linux/arch/sh/Kconfig.debug (revision b7bde87b)

# SPDX-License-Identifier: GPL-2.0

config SH_STANDARD_BIOS
	bool "Use LinuxSH standard BIOS"
	help
	  Say Y here if your target has the gdb-sh-stub
	  package from www.m17n.org (or any conforming standard LinuxSH BIOS)
	  in FLASH or EPROM.  The kernel will use standard BIOS calls during
	  boot for various housekeeping tasks (including calls to read and
	  write characters to a system console, get a MAC address from an
	  on-board Ethernet interface, and shut down the hardware).  Note this
	  does not work with machines with an existing operating system in
	  mask ROM and no flash (WindowsCE machines fall in this category).
	  If unsure, say N.

config STACK_DEBUG
	bool "Check for stack overflows"
	depends on DEBUG_KERNEL && PRINTK
	help
	  This option will cause messages to be printed if free stack space
	  drops below a certain limit. Saying Y here will add overhead to
	  every function call and will therefore incur a major
	  performance hit. Most users should say N.

config EARLY_PRINTK
	bool "Early printk"
	depends on SH_STANDARD_BIOS
	help
	  Say Y here to redirect kernel printk messages to the serial port
	  used by the SH-IPL bootloader, starting very early in the boot
	  process and ending when the kernel's serial console is initialised.
	  This option is only useful while porting the kernel to a new machine,
	  when the kernel may crash or hang before the serial console is
	  initialised.  If unsure, say N.

config 4KSTACKS
	bool "Use 4Kb for kernel stacks instead of 8Kb"
	depends on DEBUG_KERNEL && (MMU || BROKEN) && !PAGE_SIZE_64KB
	help
	  If you say Y here the kernel will use a 4Kb stacksize for the
	  kernel stack attached to each process/thread. This facilitates
	  running more threads on a system and also reduces the pressure
	  on the VM subsystem for higher order allocations. This option
	  will also use IRQ stacks to compensate for the reduced stackspace.

config IRQSTACKS
	bool "Use separate kernel stacks when processing interrupts"
	depends on DEBUG_KERNEL && BROKEN
	help
	  If you say Y here the kernel will use separate kernel stacks
	  for handling hard and soft interrupts.  This can help avoid
	  overflowing the process kernel stacks.

config DUMP_CODE
	bool "Show disassembly of nearby code in register dumps"
	depends on DEBUG_KERNEL
	default y if DEBUG_BUGVERBOSE
	default n
	help
	  This prints out a code trace of the instructions leading up to
	  the faulting instruction as a debugging aid. As this does grow
	  the kernel in size a bit, most users will want to say N here.

	  Those looking for more verbose debugging output should say Y.

config DWARF_UNWINDER
	bool "Enable the DWARF unwinder for stacktraces"
	depends on DEBUG_KERNEL
	select FRAME_POINTER
	default n
	help
	  Enabling this option will make stacktraces more accurate, at
	  the cost of an increase in overall kernel size.

config SH_NO_BSS_INIT
	bool "Avoid zeroing BSS (to speed-up startup on suitable platforms)"
	depends on DEBUG_KERNEL
	default n
	help
	  If running in painfully slow environments, such as an RTL
	  simulation or from remote memory via SHdebug, where the memory
	  can already be guaranteed to ber zeroed on boot, say Y.

	  For all other cases, say N. If this option seems perplexing, or
	  you aren't sure, say N.

config MCOUNT
	def_bool y
	depends on STACK_DEBUG || FUNCTION_TRACER