0001 # SPDX-License-Identifier: GPL-2.0
0002
0003 config EARLY_PRINTK
0004 bool "Early printk" if EXPERT
0005 depends on SYS_HAS_EARLY_PRINTK
0006 default y
0007 help
0008 This option enables special console drivers which allow the kernel
0009 to print messages very early in the bootup process.
0010
0011 This is useful for kernel debugging when your machine crashes very
0012 early before the console code is initialized. For normal operation,
0013 it is not recommended because it looks ugly on some machines and
0014 doesn't cooperate with an X server. You should normally say N here,
0015 unless you want to debug such a crash.
0016
0017 config EARLY_PRINTK_8250
0018 bool
0019 depends on EARLY_PRINTK && USE_GENERIC_EARLY_PRINTK_8250
0020 default y
0021 help
0022 "8250/16550 and compatible serial early printk driver"
0023 If you say Y here, it will be possible to use a 8250/16550 serial
0024 port as the boot console.
0025
0026 config USE_GENERIC_EARLY_PRINTK_8250
0027 bool
0028
0029 config CMDLINE_BOOL
0030 bool "Built-in kernel command line"
0031 help
0032 For most systems, it is firmware or second stage bootloader that
0033 by default specifies the kernel command line options. However,
0034 it might be necessary or advantageous to either override the
0035 default kernel command line or add a few extra options to it.
0036 For such cases, this option allows you to hardcode your own
0037 command line options directly into the kernel. For that, you
0038 should choose 'Y' here, and fill in the extra boot arguments
0039 in CONFIG_CMDLINE.
0040
0041 The built-in options will be concatenated to the default command
0042 line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
0043 command line will be ignored and replaced by the built-in string.
0044
0045 Most MIPS systems will normally expect 'N' here and rely upon
0046 the command line from the firmware or the second-stage bootloader.
0047
0048 config CMDLINE
0049 string "Default kernel command string"
0050 depends on CMDLINE_BOOL
0051 help
0052 On some platforms, there is currently no way for the boot loader to
0053 pass arguments to the kernel. For these platforms, and for the cases
0054 when you want to add some extra options to the command line or ignore
0055 the default command line, you can supply some command-line options at
0056 build time by entering them here. In other cases you can specify
0057 kernel args so that you don't have to set them up in board prom
0058 initialization routines.
0059
0060 For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
0061 options.
0062
0063 config CMDLINE_OVERRIDE
0064 bool "Built-in command line overrides firmware arguments"
0065 depends on CMDLINE_BOOL
0066 help
0067 By setting this option to 'Y' you will have your kernel ignore
0068 command line arguments from firmware or second stage bootloader.
0069 Instead, the built-in command line will be used exclusively.
0070
0071 Normally, you will choose 'N' here.
0072
0073 config SB1XXX_CORELIS
0074 bool "Corelis Debugger"
0075 depends on SIBYTE_SB1xxx_SOC
0076 select DEBUG_KERNEL if !COMPILE_TEST
0077 select DEBUG_INFO if !COMPILE_TEST
0078 help
0079 Select compile flags that produce code that can be processed by the
0080 Corelis mksym utility and UDB Emulator.
0081
0082 config DEBUG_ZBOOT
0083 bool "Enable compressed kernel support debugging"
0084 depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
0085 default n
0086 help
0087 If you want to add compressed kernel support to a new board, and the
0088 board supports uart16550 compatible serial port, please select
0089 SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
0090 debug it.
0091
0092 If your board doesn't support uart16550 compatible serial port, you
0093 can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
0094 debug it. for example, add a new serial port support just as
0095 arch/mips/boot/compressed/uart-16550.c does.
0096
0097 After the compressed kernel support works, please disable this option
0098 to reduce the kernel image size and speed up the booting procedure a
0099 little.
0100
0101 config ZBOOT_INGENIC_UART
0102 int "UART to use for compressed kernel debugging"
0103 depends on DEBUG_ZBOOT && MACH_INGENIC_SOC
0104 default 0
0105 range 0 4
0106 help
0107 Specify the UART that should be used for compressed kernel debugging.
0108
0109 config SPINLOCK_TEST
0110 bool "Enable spinlock timing tests in debugfs"
0111 depends on DEBUG_FS
0112 default n
0113 help
0114 Add several files to the debugfs to test spinlock speed.
0115
0116 config SCACHE_DEBUGFS
0117 bool "L2 cache debugfs entries"
0118 depends on DEBUG_FS
0119 help
0120 Enable this to allow parts of the L2 cache configuration, such as
0121 whether or not prefetching is enabled, to be exposed to userland
0122 via debugfs.
0123
0124 If unsure, say N.
0125
0126 menuconfig MIPS_CPS_NS16550_BOOL
0127 bool "CPS SMP NS16550 UART output"
0128 depends on MIPS_CPS
0129 help
0130 Output debug information via an ns16550 compatible UART if exceptions
0131 occur early in the boot process of a secondary core.
0132
0133 if MIPS_CPS_NS16550_BOOL
0134
0135 config MIPS_CPS_NS16550
0136 def_bool MIPS_CPS_NS16550_BASE != 0
0137
0138 config MIPS_CPS_NS16550_BASE
0139 hex "UART Base Address"
0140 default 0x1b0003f8 if MIPS_MALTA
0141 default 0
0142 help
0143 The base address of the ns16550 compatible UART on which to output
0144 debug information from the early stages of core startup.
0145
0146 This is only used if non-zero.
0147
0148 config MIPS_CPS_NS16550_SHIFT
0149 int "UART Register Shift"
0150 default 0
0151 help
0152 The number of bits to shift ns16550 register indices by in order to
0153 form their addresses. That is, log base 2 of the span between
0154 adjacent ns16550 registers in the system.
0155
0156 config MIPS_CPS_NS16550_WIDTH
0157 int "UART Register Width"
0158 default 1
0159 help
0160 ns16550 registers width. UART registers IO access methods will be
0161 selected in accordance with this parameter. By setting it to 1, 2 or
0162 4 UART registers will be accessed by means of lb/sb, lh/sh or lw/sw
0163 instructions respectively. Any value not from that set activates
0164 lb/sb instructions.
0165
0166 endif # MIPS_CPS_NS16550_BOOL
