# SPDX-License-Identifier: GPL-2.0 config EARLY_PRINTK bool "Early printk" if EXPERT depends on SYS_HAS_EARLY_PRINTK default y help 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. config EARLY_PRINTK_8250 bool depends on EARLY_PRINTK && USE_GENERIC_EARLY_PRINTK_8250 default y help "8250/16550 and compatible serial early printk driver" If you say Y here, it will be possible to use a 8250/16550 serial port as the boot console. config USE_GENERIC_EARLY_PRINTK_8250 bool config CMDLINE_BOOL bool "Built-in kernel command line" 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 MIPS 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 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" 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. config SB1XXX_CORELIS bool "Corelis Debugger" depends on SIBYTE_SB1xxx_SOC select DEBUG_KERNEL if !COMPILE_TEST select DEBUG_INFO if !COMPILE_TEST help Select compile flags that produce code that can be processed by the Corelis mksym utility and UDB Emulator. 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/mips/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 ZBOOT_INGENIC_UART int "UART to use for compressed kernel debugging" depends on DEBUG_ZBOOT && MACH_INGENIC_SOC default 0 range 0 4 help Specify the UART that should be used for compressed kernel debugging. 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. config SCACHE_DEBUGFS bool "L2 cache debugfs entries" depends on DEBUG_FS help Enable this to allow parts of the L2 cache configuration, such as whether or not prefetching is enabled, to be exposed to userland via debugfs. If unsure, say N. menuconfig MIPS_CPS_NS16550_BOOL bool "CPS SMP NS16550 UART output" depends on MIPS_CPS help Output debug information via an ns16550 compatible UART if exceptions occur early in the boot process of a secondary core. if MIPS_CPS_NS16550_BOOL config MIPS_CPS_NS16550 def_bool MIPS_CPS_NS16550_BASE != 0 config MIPS_CPS_NS16550_BASE hex "UART Base Address" default 0x1b0003f8 if MIPS_MALTA default 0 help The base address of the ns16550 compatible UART on which to output debug information from the early stages of core startup. This is only used if non-zero. config MIPS_CPS_NS16550_SHIFT int "UART Register Shift" default 0 help The number of bits to shift ns16550 register indices by in order to form their addresses. That is, log base 2 of the span between adjacent ns16550 registers in the system. config MIPS_CPS_NS16550_WIDTH int "UART Register Width" default 1 help ns16550 registers width. UART registers IO access methods will be selected in accordance with this parameter. By setting it to 1, 2 or 4 UART registers will be accessed by means of lb/sb, lh/sh or lw/sw instructions respectively. Any value not from that set activates lb/sb instructions. endif # MIPS_CPS_NS16550_BOOL