menu "Kernel hacking"
bool "Early printk" if EXPERT
depends on SYS_HAS_EARLY_PRINTK
This option enables special console drivers which allow the kernel
to print messages very early in the bootup process.
This is useful for kernel debugging when your machine crashes very
early before the console code is initialized. For normal operation,
it is not recommended because it looks ugly on some machines and
doesn't cooperate with an X server. You should normally say N here,
unless you want to debug such a crash.
bool "8250/16550 and compatible serial early printk driver"
depends on EARLY_PRINTK
If you say Y here, it will be possible to use a 8250/16550 serial
port as the boot console.
bool "Built-in kernel command line"
For most systems, it is firmware or second stage bootloader that
by default specifies the kernel command line options. However,
it might be necessary or advantageous to either override the
default kernel command line or add a few extra options to it.
For such cases, this option allows you to hardcode your own
command line options directly into the kernel. For that, you
should choose 'Y' here, and fill in the extra boot arguments
The built-in options will be concatenated to the default command
line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
command line will be ignored and replaced by the built-in string.
Most MIPS systems will normally expect 'N' here and rely upon
the command line from the firmware or the second-stage bootloader.
string "Default kernel command string"
depends on CMDLINE_BOOL
On some platforms, there is currently no way for the boot loader to
pass arguments to the kernel. For these platforms, and for the cases
when you want to add some extra options to the command line or ignore
the default command line, you can supply some command-line options at
build time by entering them here. In other cases you can specify
kernel args so that you don't have to set them up in board prom
For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
bool "Built-in command line overrides firmware arguments"
depends on CMDLINE_BOOL
By setting this option to 'Y' you will have your kernel ignore
command line arguments from firmware or second stage bootloader.
Instead, the built-in command line will be used exclusively.
Normally, you will choose 'N' here.
bool "Enable additional debug checks before going into CPU idle loop"
depends on DEBUG_KERNEL && MIPS_MT_SMTC
This option enables Enable additional debug checks before going into
CPU idle loop. For details on these checks, see
arch/mips/kernel/smtc.c. This debugging option result in significant
overhead so should be disabled in production kernels.
bool "Corelis Debugger"
depends on SIBYTE_SB1xxx_SOC
Select compile flags that produce code that can be processed by the
Corelis mksym utility and UDB Emulator.
bool "Enable run-time debugging"
depends on DEBUG_KERNEL
If you say Y here, some debugging macros will do run-time checking.
If you say N here, those macros will mostly turn to no-ops. See
arch/mips/include/asm/debug.h for debugging macros.
If unsure, say N.
bool "Enable compressed kernel support debugging"
depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
If you want to add compressed kernel support to a new board, and the
board supports uart16550 compatible serial port, please select
SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
If your board doesn't support uart16550 compatible serial port, you
can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
debug it. for example, add a new serial port support just as
After the compressed kernel support works, please disable this option
to reduce the kernel image size and speed up the booting procedure a
bool "Enable spinlock timing tests in debugfs"
depends on DEBUG_FS
Add several files to the debugfs to test spinlock speed.