1 # SPDX-License-Identifier: GPL-2.0 1 # SPDX-License-Identifier: GPL-2.0
2 2
3 config EARLY_PRINTK 3 config EARLY_PRINTK
4 bool "Activate early kernel debugging" !! 4 bool "Early printk" if EXPERT
>> 5 depends on SYS_HAS_EARLY_PRINTK
5 default y 6 default y
6 depends on TTY <<
7 select SERIAL_CORE_CONSOLE <<
8 help 7 help
9 Enable early printk on console. !! 8 This option enables special console drivers which allow the kernel
>> 9 to print messages very early in the bootup process.
>> 10
10 This is useful for kernel debugging 11 This is useful for kernel debugging when your machine crashes very
11 early before the console code is ini !! 12 early before the console code is initialized. For normal operation,
12 You should normally say N here, unle !! 13 it is not recommended because it looks ugly on some machines and
>> 14 doesn't cooperate with an X server. You should normally say N here,
>> 15 unless you want to debug such a crash.
>> 16
>> 17 config EARLY_PRINTK_8250
>> 18 bool
>> 19 depends on EARLY_PRINTK && USE_GENERIC_EARLY_PRINTK_8250
>> 20 default y
>> 21 help
>> 22 "8250/16550 and compatible serial early printk driver"
>> 23 If you say Y here, it will be possible to use a 8250/16550 serial
>> 24 port as the boot console.
>> 25
>> 26 config USE_GENERIC_EARLY_PRINTK_8250
>> 27 bool
>> 28
>> 29 config CMDLINE_BOOL
>> 30 bool "Built-in kernel command line"
>> 31 help
>> 32 For most systems, it is firmware or second stage bootloader that
>> 33 by default specifies the kernel command line options. However,
>> 34 it might be necessary or advantageous to either override the
>> 35 default kernel command line or add a few extra options to it.
>> 36 For such cases, this option allows you to hardcode your own
>> 37 command line options directly into the kernel. For that, you
>> 38 should choose 'Y' here, and fill in the extra boot arguments
>> 39 in CONFIG_CMDLINE.
>> 40
>> 41 The built-in options will be concatenated to the default command
>> 42 line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
>> 43 command line will be ignored and replaced by the built-in string.
>> 44
>> 45 Most MIPS systems will normally expect 'N' here and rely upon
>> 46 the command line from the firmware or the second-stage bootloader.
>> 47
>> 48 config CMDLINE
>> 49 string "Default kernel command string"
>> 50 depends on CMDLINE_BOOL
>> 51 help
>> 52 On some platforms, there is currently no way for the boot loader to
>> 53 pass arguments to the kernel. For these platforms, and for the cases
>> 54 when you want to add some extra options to the command line or ignore
>> 55 the default command line, you can supply some command-line options at
>> 56 build time by entering them here. In other cases you can specify
>> 57 kernel args so that you don't have to set them up in board prom
>> 58 initialization routines.
>> 59
>> 60 For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
>> 61 options.
>> 62
>> 63 config CMDLINE_OVERRIDE
>> 64 bool "Built-in command line overrides firmware arguments"
>> 65 depends on CMDLINE_BOOL
>> 66 help
>> 67 By setting this option to 'Y' you will have your kernel ignore
>> 68 command line arguments from firmware or second stage bootloader.
>> 69 Instead, the built-in command line will be used exclusively.
>> 70
>> 71 Normally, you will choose 'N' here.
>> 72
>> 73 config SB1XXX_CORELIS
>> 74 bool "Corelis Debugger"
>> 75 depends on SIBYTE_SB1xxx_SOC
>> 76 select DEBUG_KERNEL if !COMPILE_TEST
>> 77 select DEBUG_INFO if !COMPILE_TEST
>> 78 help
>> 79 Select compile flags that produce code that can be processed by the
>> 80 Corelis mksym utility and UDB Emulator.
>> 81
>> 82 config DEBUG_ZBOOT
>> 83 bool "Enable compressed kernel support debugging"
>> 84 depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
>> 85 default n
>> 86 help
>> 87 If you want to add compressed kernel support to a new board, and the
>> 88 board supports uart16550 compatible serial port, please select
>> 89 SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
>> 90 debug it.
>> 91
>> 92 If your board doesn't support uart16550 compatible serial port, you
>> 93 can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
>> 94 debug it. for example, add a new serial port support just as
>> 95 arch/mips/boot/compressed/uart-16550.c does.
>> 96
>> 97 After the compressed kernel support works, please disable this option
>> 98 to reduce the kernel image size and speed up the booting procedure a
>> 99 little.
>> 100
>> 101 config ZBOOT_INGENIC_UART
>> 102 int "UART to use for compressed kernel debugging"
>> 103 depends on DEBUG_ZBOOT && MACH_INGENIC_SOC
>> 104 default 0
>> 105 range 0 4
>> 106 help
>> 107 Specify the UART that should be used for compressed kernel debugging.
>> 108
>> 109 config SPINLOCK_TEST
>> 110 bool "Enable spinlock timing tests in debugfs"
>> 111 depends on DEBUG_FS
>> 112 default n
>> 113 help
>> 114 Add several files to the debugfs to test spinlock speed.
>> 115
>> 116 config SCACHE_DEBUGFS
>> 117 bool "L2 cache debugfs entries"
>> 118 depends on DEBUG_FS
>> 119 help
>> 120 Enable this to allow parts of the L2 cache configuration, such as
>> 121 whether or not prefetching is enabled, to be exposed to userland
>> 122 via debugfs.
>> 123
>> 124 If unsure, say N.
>> 125
>> 126 menuconfig MIPS_CPS_NS16550_BOOL
>> 127 bool "CPS SMP NS16550 UART output"
>> 128 depends on MIPS_CPS
>> 129 help
>> 130 Output debug information via an ns16550 compatible UART if exceptions
>> 131 occur early in the boot process of a secondary core.
>> 132
>> 133 if MIPS_CPS_NS16550_BOOL
>> 134
>> 135 config MIPS_CPS_NS16550
>> 136 def_bool MIPS_CPS_NS16550_BASE != 0
>> 137
>> 138 config MIPS_CPS_NS16550_BASE
>> 139 hex "UART Base Address"
>> 140 default 0x1b0003f8 if MIPS_MALTA
>> 141 default 0
>> 142 help
>> 143 The base address of the ns16550 compatible UART on which to output
>> 144 debug information from the early stages of core startup.
>> 145
>> 146 This is only used if non-zero.
>> 147
>> 148 config MIPS_CPS_NS16550_SHIFT
>> 149 int "UART Register Shift"
>> 150 default 0
>> 151 help
>> 152 The number of bits to shift ns16550 register indices by in order to
>> 153 form their addresses. That is, log base 2 of the span between
>> 154 adjacent ns16550 registers in the system.
>> 155
>> 156 config MIPS_CPS_NS16550_WIDTH
>> 157 int "UART Register Width"
>> 158 default 1
>> 159 help
>> 160 ns16550 registers width. UART registers IO access methods will be
>> 161 selected in accordance with this parameter. By setting it to 1, 2 or
>> 162 4 UART registers will be accessed by means of lb/sb, lh/sh or lw/sw
>> 163 instructions respectively. Any value not from that set activates
>> 164 lb/sb instructions.
>> 165
>> 166 endif # MIPS_CPS_NS16550_BOOL
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