blob: b43e288ec56749d73be4b2de45a505ad6dbaa41c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001menu "Kernel hacking"
2
Ralf Baechle192ef362006-07-07 14:07:18 +01003config TRACE_IRQFLAGS_SUPPORT
4 bool
5 default y
6
Linus Torvalds1da177e2005-04-16 15:20:36 -07007source "lib/Kconfig.debug"
8
Ralf Baechle4dd92e12009-12-17 01:57:30 +00009config EARLY_PRINTK
David Rientjes6a108a12011-01-20 14:44:16 -080010 bool "Early printk" if EXPERT
Ralf Baechle4dd92e12009-12-17 01:57:30 +000011 depends on SYS_HAS_EARLY_PRINTK
12 default y
13 help
14 This option enables special console drivers which allow the kernel
15 to print messages very early in the bootup process.
16
17 This is useful for kernel debugging when your machine crashes very
18 early before the console code is initialized. For normal operation,
19 it is not recommended because it looks ugly on some machines and
20 doesn't cooperate with an X server. You should normally say N here,
21 unless you want to debug such a crash.
22
Yoichi Yuasa7cd93b82010-02-08 20:59:39 +090023config EARLY_PRINTK_8250
Ralf Baechlee6086552014-03-26 21:40:25 +010024 bool
25 depends on EARLY_PRINTK && USE_GENERIC_EARLY_PRINTK_8250
26 default y
Yoichi Yuasa7cd93b82010-02-08 20:59:39 +090027 help
Ralf Baechlee6086552014-03-26 21:40:25 +010028 "8250/16550 and compatible serial early printk driver"
Yoichi Yuasa7cd93b82010-02-08 20:59:39 +090029 If you say Y here, it will be possible to use a 8250/16550 serial
30 port as the boot console.
31
Ralf Baechlee6086552014-03-26 21:40:25 +010032config USE_GENERIC_EARLY_PRINTK_8250
33 bool
34
Dmitri Vorobiev6acc7d42009-11-21 22:34:41 +020035config CMDLINE_BOOL
36 bool "Built-in kernel command line"
37 default n
38 help
39 For most systems, it is firmware or second stage bootloader that
40 by default specifies the kernel command line options. However,
41 it might be necessary or advantageous to either override the
42 default kernel command line or add a few extra options to it.
43 For such cases, this option allows you to hardcode your own
44 command line options directly into the kernel. For that, you
45 should choose 'Y' here, and fill in the extra boot arguments
46 in CONFIG_CMDLINE.
47
48 The built-in options will be concatenated to the default command
49 line if CMDLINE_OVERRIDE is set to 'N'. Otherwise, the default
50 command line will be ignored and replaced by the built-in string.
51
52 Most MIPS systems will normally expect 'N' here and rely upon
53 the command line from the firmware or the second-stage bootloader.
54
Linus Torvalds1da177e2005-04-16 15:20:36 -070055config CMDLINE
56 string "Default kernel command string"
Dmitri Vorobiev6acc7d42009-11-21 22:34:41 +020057 depends on CMDLINE_BOOL
Linus Torvalds1da177e2005-04-16 15:20:36 -070058 default ""
59 help
Jan Altenberg3e7f9b822007-01-25 20:46:14 +010060 On some platforms, there is currently no way for the boot loader to
Dmitri Vorobiev6acc7d42009-11-21 22:34:41 +020061 pass arguments to the kernel. For these platforms, and for the cases
62 when you want to add some extra options to the command line or ignore
63 the default command line, you can supply some command-line options at
64 build time by entering them here. In other cases you can specify
65 kernel args so that you don't have to set them up in board prom
66 initialization routines.
67
68 For more information, see the CMDLINE_BOOL and CMDLINE_OVERRIDE
69 options.
70
71config CMDLINE_OVERRIDE
Masanari Iida6b2aac42012-04-14 00:14:11 +090072 bool "Built-in command line overrides firmware arguments"
Dmitri Vorobiev6acc7d42009-11-21 22:34:41 +020073 default n
74 depends on CMDLINE_BOOL
75 help
76 By setting this option to 'Y' you will have your kernel ignore
77 command line arguments from firmware or second stage bootloader.
78 Instead, the built-in command line will be used exclusively.
79
80 Normally, you will choose 'N' here.
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Linus Torvalds1da177e2005-04-16 15:20:36 -070082config SB1XXX_CORELIS
83 bool "Corelis Debugger"
84 depends on SIBYTE_SB1xxx_SOC
85 select DEBUG_INFO
86 help
87 Select compile flags that produce code that can be processed by the
88 Corelis mksym utility and UDB Emulator.
89
Wu Zhangjinf86a69b2010-01-31 20:39:40 +080090config DEBUG_ZBOOT
91 bool "Enable compressed kernel support debugging"
92 depends on DEBUG_KERNEL && SYS_SUPPORTS_ZBOOT
93 default n
94 help
95 If you want to add compressed kernel support to a new board, and the
96 board supports uart16550 compatible serial port, please select
97 SYS_SUPPORTS_ZBOOT_UART16550 for your board and enable this option to
98 debug it.
99
100 If your board doesn't support uart16550 compatible serial port, you
101 can try to select SYS_SUPPORTS_ZBOOT and use the other methods to
102 debug it. for example, add a new serial port support just as
103 arch/mips/boot/compressed/uart-16550.c does.
104
105 After the compressed kernel support works, please disable this option
106 to reduce the kernel image size and speed up the booting procedure a
107 little.
108
David Daneybba90762010-02-16 15:26:35 -0800109config 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
Paul Burtonc1a0e9b2015-09-22 10:07:41 -0700116if CPU_MIPSR6
117
118choice
119 prompt "Compact branch policy"
120 default MIPS_COMPACT_BRANCHES_OPTIMAL
121
122config MIPS_COMPACT_BRANCHES_NEVER
123 bool "Never (force delay slot branches)"
124 help
125 Pass the -mcompact-branches=never flag to the compiler in order to
126 force it to always emit branches with delay slots, and make no use
127 of the compact branch instructions introduced by MIPSr6. This is
128 useful if you suspect there may be an issue with compact branches in
129 either the compiler or the CPU.
130
131config MIPS_COMPACT_BRANCHES_OPTIMAL
132 bool "Optimal (use where beneficial)"
133 help
134 Pass the -mcompact-branches=optimal flag to the compiler in order for
135 it to make use of compact branch instructions where it deems them
136 beneficial, and use branches with delay slots elsewhere. This is the
137 default compiler behaviour, and should be used unless you have a
138 reason to choose otherwise.
139
140config MIPS_COMPACT_BRANCHES_ALWAYS
141 bool "Always (force compact branches)"
142 help
143 Pass the -mcompact-branches=always flag to the compiler in order to
144 force it to always emit compact branches, making no use of branch
145 instructions with delay slots. This can result in more compact code
146 which may be beneficial in some scenarios.
147
148endchoice
149
150endif # CPU_MIPSR6
151
Paul Burtond478b082015-09-22 10:10:56 -0700152config SCACHE_DEBUGFS
153 bool "L2 cache debugfs entries"
154 depends on DEBUG_FS
155 help
156 Enable this to allow parts of the L2 cache configuration, such as
157 whether or not prefetching is enabled, to be exposed to userland
158 via debugfs.
159
160 If unsure, say N.
161
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162endmenu