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gerrit-public.fairphone.software / kernel / msm-4.9 / 73d8a12f05292d86623b4ec7bf5fd75d5ad5f687 / . / usr / Kconfig
blob: 5166078d45f2dae85150ac79a4c0cf342fc83fe4 [file] [log] [blame]
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200[diff] [blame]1#
2# Configuration for initramfs
3#
4
5config INITRAMFS_SOURCE
6 string "Initramfs source file(s)"
7 default ""
8 help
9 This can be either a single cpio archive with a .cpio suffix or a
10 space-separated list of directories and files for building the
11 initramfs image. A cpio archive should contain a filesystem archive
12 to be used as an initramfs image. Directories should contain a
13 filesystem layout to be included in the initramfs image. Files
14 should contain entries according to the format described by the
15 "usr/gen_init_cpio" program in the kernel tree.
16
17 When multiple directories and files are specified then the
18 initramfs image will be the aggregate of all of them.
19
Alexander E. Patrakov0979f372007-03-16 18:01:45 +0500[diff] [blame]20 See <file:Documentation/early-userspace/README> for more details.
Sam Ravnborgdbec4862005-08-10 20:44:50 +0200[diff] [blame]21
22 If you are not sure, leave it blank.
23
24config INITRAMFS_ROOT_UID
25 int "User ID to map to 0 (user root)"
26 depends on INITRAMFS_SOURCE!=""
27 default "0"
28 help
29 This setting is only meaningful if the INITRAMFS_SOURCE is
30 contains a directory. Setting this user ID (UID) to something
31 other than "0" will cause all files owned by that UID to be
32 owned by user root in the initial ramdisk image.
33
34 If you are not sure, leave it set to "0".
35
36config INITRAMFS_ROOT_GID
37 int "Group ID to map to 0 (group root)"
38 depends on INITRAMFS_SOURCE!=""
39 default "0"
40 help
41 This setting is only meaningful if the INITRAMFS_SOURCE is
42 contains a directory. Setting this group ID (GID) to something
43 other than "0" will cause all files owned by that GID to be
44 owned by group root in the initial ramdisk image.
45
46 If you are not sure, leave it set to "0".
H. Peter Anvinfb9a4ca2009-01-07 00:03:49 -0800[diff] [blame]47
48config RD_GZIP
H. Peter Anvin73d8a122009-03-28 15:49:08 -0700[diff] [blame^]49 bool "Initial ramdisk compressed using gzip" if EMBEDDED
H. Peter Anvinfb9a4ca2009-01-07 00:03:49 -0800[diff] [blame]50 default y
H. Peter Anvin73d8a122009-03-28 15:49:08 -0700[diff] [blame^]51 depends on BLK_DEV_INITRD
H. Peter Anvinfb9a4ca2009-01-07 00:03:49 -0800[diff] [blame]52 select DECOMPRESS_GZIP
53 help
54 Support loading of a gzip encoded initial ramdisk or cpio buffer.
55 If unsure, say Y.
56
57config RD_BZIP2
H. Peter Anvin73d8a122009-03-28 15:49:08 -0700[diff] [blame^]58 bool "Initial ramdisk compressed using bzip2" if EMBEDDED
59 default !EMBEDDED
60 depends on BLK_DEV_INITRD
H. Peter Anvinfb9a4ca2009-01-07 00:03:49 -0800[diff] [blame]61 select DECOMPRESS_BZIP2
62 help
63 Support loading of a bzip2 encoded initial ramdisk or cpio buffer
64 If unsure, say N.
65
66config RD_LZMA
H. Peter Anvin73d8a122009-03-28 15:49:08 -0700[diff] [blame^]67 bool "Initial ramdisk compressed using lzma" if EMBEDDED
68 default !EMBEDDED
69 depends on BLK_DEV_INITRD
H. Peter Anvinfb9a4ca2009-01-07 00:03:49 -0800[diff] [blame]70 select DECOMPRESS_LZMA
71 help
72 Support loading of a lzma encoded initial ramdisk or cpio buffer
73 If unsure, say N.
Alain Knaffab76f3d2009-02-19 13:43:51 -0800[diff] [blame]74
75choice
76 prompt "Built-in initramfs compression mode"
77 help
78 This setting is only meaningful if the INITRAMFS_SOURCE is
79 set. It decides by which algorithm the INITRAMFS_SOURCE will
80 be compressed.
81 Several compression algorithms are available, which differ
82 in efficiency, compression and decompression speed.
83 Compression speed is only relevant when building a kernel.
84 Decompression speed is relevant at each boot.
85
86 If you have any problems with bzip2 or lzma compressed
87 initramfs, mail me (Alain Knaff) <alain@knaff.lu>.
88
89 High compression options are mostly useful for users who
90 are low on disk space (embedded systems), but for whom ram
91 size matters less.
92
93 If in doubt, select 'gzip'
94
95config INITRAMFS_COMPRESSION_NONE
96 bool "None"
97 help
98 Do not compress the built-in initramfs at all. This may
99 sound wasteful in space, but, you should be aware that the
100 built-in initramfs will be compressed at a later stage
101 anyways along with the rest of the kernel, on those
102 architectures that support this.
103 However, not compressing the initramfs may lead to slightly
104 higher memory consumption during a short time at boot, while
105 both the cpio image and the unpacked filesystem image will
106 be present in memory simultaneously
107
108config INITRAMFS_COMPRESSION_GZIP
109 bool "Gzip"
110 depends on RD_GZIP
111 help
112 The old and tried gzip compression. Its compression ratio is
113 the poorest among the 3 choices; however its speed (both
114 compression and decompression) is the fastest.
115
116config INITRAMFS_COMPRESSION_BZIP2
117 bool "Bzip2"
118 depends on RD_BZIP2
119 help
120 Its compression ratio and speed is intermediate.
121 Decompression speed is slowest among the three. The initramfs
122 size is about 10% smaller with bzip2, in comparison to gzip.
123 Bzip2 uses a large amount of memory. For modern kernels you
124 will need at least 8MB RAM or more for booting.
125
126config INITRAMFS_COMPRESSION_LZMA
127 bool "LZMA"
128 depends on RD_LZMA
129 help
130 The most recent compression algorithm.
131 Its ratio is best, decompression speed is between the other
132 two. Compression is slowest. The initramfs size is about 33%
133 smaller with LZMA in comparison to gzip.
134
135endchoice