# SPDX-License-Identifier: GPL-2.0 config CMDLINE_BOOL bool "Built-in kernel command line" default n help 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 in CONFIG_CMDLINE. 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 LoongArch systems will normally expect 'N' here and rely upon the command line from the firmware or the second-stage bootloader. config CMDLINE string "Default kernel command string" depends on CMDLINE_BOOL default "" help 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 initialization routines. For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE options. config CMDLINE_OVERRIDE bool "Built-in command line overrides firmware arguments" default n depends on CMDLINE_BOOL help 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. choice prompt "Choose kernel unwinder" default UNWINDER_PROLOGUE if KALLSYMS help This determines which method will be used for unwinding kernel stack traces for panics, oopses, bugs, warnings, perf, /proc//stack, livepatch, lockdep, and more. config UNWINDER_GUESS bool "Guess unwinder" help This option enables the "guess" unwinder for unwinding kernel stack traces. It scans the stack and reports every kernel text address it finds. Some of the addresses it reports may be incorrect. config UNWINDER_PROLOGUE bool "Prologue unwinder" depends on KALLSYMS help This option enables the "prologue" unwinder for unwinding kernel stack traces. It unwind the stack frame based on prologue code analyze. Symbol information is needed, at least the address and length of each function. Some of the addresses it reports may be incorrect. config UNWINDER_ORC bool "ORC unwinder" select STACK_VALIDATION help This option enables the ORC (Oops Rewind Capability) unwinder for unwinding kernel stack traces. It uses a custom data format which is a simplified version of the DWARF Call Frame Information standard. This unwinder is more accurate across interrupt entry frames than the frame pointer unwinder. It also enables a 5-10% performance improvement across the entire kernel compared to frame pointers. Enabling this option will increase the kernel's runtime memory usage by roughly 3-5MB, depending on your kernel config. endchoice config DEBUG_ZBOOT bool "Enable compressed kernel support debugging" depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT default n help 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 debug it. 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 arch/loongarch/boot/compressed/uart-16550.c does. After the compressed kernel support works, please disable this option to reduce the kernel image size and speed up the booting procedure a little. config SPINLOCK_TEST bool "Enable spinlock timing tests in debugfs" depends on DEBUG_FS default n help Add several files to the debugfs to test spinlock speed.