JFFS2 images over UBI layer - Revision history

Mike: JFFS2 images over UBI layer moved to Linux: JFFS2 images over UBI layer

2009-12-23T08:08:19Z

JFFS2 images over UBI layer moved to Linux: JFFS2 images over UBI layer

Mike: 1 revision(s)

2009-11-26T08:46:25Z

1 revision(s)

Grinberg: /* Kernel support */

2009-11-22T14:23:17Z

‎Kernel support

Mike: 1 revision(s)

2009-07-01T12:31:49Z

1 revision(s)

Mike at 12:24, 1 July 2009

2009-07-01T12:24:15Z

New page

On this page we assume, that you have MTD utils installed as described in [[Linux_Development_for_XScale_modules#MTD_utils|Linux Development for XScale modules]] article.

== Kernel support ==

In order to get UBI and UBI GLUE driver working you need to enable them in kernel configuration. In kernel configuration choose '''"Device Drivers -> Memory Technology Device (MTD) support -> UBI - Unsorted block images"''' menu and enable '''"Enable UBI"''' and '''"Emulate MTD devices"''' options.
<pre>
┌─────────────────────────────────── UBI - Unsorted block images ────────────────────────────────────┐
│ Arrow keys navigate the menu. <Enter> selects submenus --->. Highlighted letters are hotkeys. │
│ Pressing <Y> includes, <N> excludes, <M> modularizes features. Press <Esc><Esc> to exit, <?> for │
│ Help, </> for Search. Legend: [*] built-in [ ] excluded <M> module < > module capable │
│ │
│ ┌────────────────────────────────────────────────────────────────────────────────────────────────┐ │
│ │ <*> Enable UBI │ │
│ │ (4096) UBI wear-leveling threshold (NEW) │ │
│ │ (1) Percentage of reserved eraseblocks for bad eraseblocks handling (NEW) │ │
│ │ [*] Emulate MTD devices │ │
│ │ *** UBI debugging options *** │ │
│ │ [ ] UBI debugging (NEW) │ │
│ │ │ │
│ └────────────────────────────────────────────────────────────────────────────────────────────────┘ │
├────────────────────────────────────────────────────────────────────────────────────────────────────┤
│ <Select> < Exit > < Help > │
└────────────────────────────────────────────────────────────────────────────────────────────────────┘
</pre>
Now you can build the kernel with UBI support including the UBI GLUE driver.

== User space tools ==

In this section we will use {{parameter|X}} as the MTD partition number attached to UBI, {{parameter|Y}} as the emulated MTD partition number and we assume that there were no MTD partitions attached to UBI before. <br>
To prepare the NAND for use with UBI, you should take the following steps:
* Erase the MTD partition that will be used for UBI volume(s):
<pre>
> flash_eraseall /dev/mtdX
</pre>
* Attach the MTD partition to UBI:
<pre>
> ubiattach /dev/ubi_ctrl -m X -O 2048
</pre>
* Create UBI volume:
<pre>
> ubimkvol /dev/ubi0 -m -N <ubi volume name>
</pre>
* Update the new UBI volume with JFFS2 image:
<pre>
> ubiupdatevol /dev/ubi0_0 <path to JFFS2 image>
</pre>
If you want to use the new UBI volume as the root filesystem on your device, you should change the {{parameter|root}} parameter of kernel command line to boot from emulated
MTD partition '''Y''' (which is UBI volume):
'''root=/dev/mtdblockY''' and add '''ubi.mtd=X,2048''' parameter, so the MTD partition containing the new UBI volume will be attached on kernel boot prior to root filesystem mount.

== JFFS2 image eraseblock size ==

UBI layer is using some part of NAND's ''physical'' erase block for it's own needs (e.g. bad blocks handling), therefore it provides a ''logical'' eraseblock for filesystem use. The logical eraseblock size is smaller than the physical, so when you construct the JFFS2 image, as described in section [[Linux_Development_for_XScale_modules#JFFS2_images|JFFS2 images]], you should set the {{parameter|eraseblock}} parameter to UBI's logical eraseblock size. <br>
The UBI logical eraseblock size can be obtained by invoking the command:
<pre>
> cat /sys/class/ubi/ubiX/eraseblock_size
</pre>
Where {{parameter|X}} is the UBI device number.

== See also ==
* [[Linux_Development_for_XScale_modules|Linux Development for XScale modules]]
* [[Linux_MTD_drivers_on_CM-X270|Linux MTD drivers on CM-X270]]
* [[Getting_started_with_Linux_on_CM-X300|Getting started with Linux on CM-X300]]
* [http://www.linux-mtd.infradead.org/doc/ubi.html UBI documentation]
* [http://www.linux-mtd.infradead.org/faq/ubi.html UBI FAQ and HOWTO]

← Older revision		Revision as of 08:08, 23 December 2009
Line 1:		Line 1:
−	~~On this page we assume, that you have MTD utils installed as described in~~ [[~~Linux_Development_for_XScale_modules#MTD_utils\|~~Linux ~~Development for XScale modules]] article.~~	+	#REDIRECT [[Linux: JFFS2 images over UBI layer]]
−
−	~~== Kernel support ==~~
−
−	In order to get UBI and UBI GLUE driver working you need to enable them in kernel configuration. In kernel configuration choose '''"Device Drivers -> Memory Technology Device (MTD) support -> UBI - Unsorted block images"''' menu and enable '''"Enable UBI"''' and '''"MTD devices emulation driver"''' options.
−	~~<pre>~~
−	┌─────────────────────────────────── UBI - Unsorted block images ────────────────────────────────────┐
−	~~│ Arrow keys navigate the menu. <Enter> selects submenus --->. Highlighted letters are hotkeys. │~~
−	~~│ Pressing <Y> includes, <N> excludes, <M> modularizes features. Press <Esc><Esc> to exit, <?> for │~~
−	~~│ Help, </> for Search. Legend: [*] built-in [ ] excluded <M> module < > module capable │~~
−	~~│ │~~
−	│ ┌────────────────────────────────────────────────────────────────────────────────────────────────┐ │
−	~~│ │ <*> Enable UBI │ │~~
−	~~│ │ (4096) UBI wear-leveling threshold │ │~~
−	~~│ │ (1) Percentage of reserved eraseblocks for bad eraseblocks handling │ │~~
−	~~│ │ <*> MTD devices emulation driver (gluebi) │ │~~
−	~~│ │ * UBI debugging options * │ │~~
−	~~│ │ [ ] UBI debugging │ │~~
−	~~│ │ │ │~~
−	│ └────────────────────────────────────────────────────────────────────────────────────────────────┘ │
−	├────────────────────────────────────────────────────────────────────────────────────────────────────┤
−	~~│ <Select> < Exit > < Help > │~~
−	└────────────────────────────────────────────────────────────────────────────────────────────────────┘
−	~~</pre>~~
−	~~Now you can build the kernel with UBI support including the UBI GLUE driver.~~
−
−	~~== User space tools ==~~
−
−	In this section we will use {{parameter\|X}} as the MTD partition number attached to UBI, {{parameter\|Y}} as the emulated MTD partition number and we assume that there were no MTD partitions attached to UBI before. <br>
−	~~To prepare the NAND for use with UBI, you should take the following steps~~:
−	* Erase the MTD partition that will be used for UBI volume(s):
−	~~<pre>~~
−	~~> flash_eraseall /dev/mtdX~~
−	~~</pre>~~
−	* Attach the MTD partition to UBI:
−	~~<pre>~~
−	~~> ubiattach /dev/ubi_ctrl -m X -O 2048~~
−	~~</pre>~~
−	* Create UBI volume:
−	~~<pre>~~
−	~~> ubimkvol /dev/ubi0 -m -N <ubi volume name>~~
−	~~</pre>~~
−	* Update the new UBI volume with JFFS2 ~~image:~~
−	~~<pre>~~
−	~~> ubiupdatevol /dev/ubi0_0 <path to JFFS2 image>~~
−	~~</pre>~~
−	~~If you want to use the new UBI volume as the root filesystem on your device, you should change the {{parameter\|root}} parameter of kernel command line to boot from emulated~~
−	~~MTD partition '''Y''' (which is UBI volume):~~
−	~~'''root=/dev/mtdblockY''' and add '''ubi.mtd=X,2048''' parameter, so the MTD partition containing the new UBI volume will be attached on kernel boot prior to root filesystem mount.~~
−
−	~~== UBI logical eraseblock size and JFFS2 image eraseblock size ==~~
−
−	UBI layer is using some part of NAND's ''physical'' erase block for it's own needs (e.g. bad blocks handling), therefore it provides a ''logical'' eraseblock for filesystem use. The logical eraseblock size is smaller than the physical, so when you construct the JFFS2/UBIFS image, as described in section [[Linux_Development_for_XScale_modules#JFFS2_images\|JFFS2 images]] and [[Linux_Development_for_XScale_modules#UBIFS_images\|UBIFS images]], you should set the {{parameter\|eraseblock}} (JFFS2) and {{parameter\|leb-size}} (UBIFS) parameter to UBI's logical eraseblock size. <br>
−	~~The UBI logical eraseblock size can be obtained by invoking the command:~~
−	~~<pre>~~
−	~~> cat /sys/class/ubi/ubiX/eraseblock_size~~
−	~~</pre>~~
−	~~Where {{parameter\|X}} is the UBI device number.~~
−
−	~~== See also ==~~
−	* [[Linux_Development_for_XScale_modules\|Linux Development for XScale modules]]
−	* [[Linux_MTD_drivers_on_CM-X270\|Linux MTD drivers on CM-X270]]
−	* [[Getting_started_with_Linux_on_CM-X300\|Getting started with Linux on CM-X300]]
−	* [http://www.linux-mtd.infradead.org/doc/ubi.html UBI documentation]
−	* [http://www.linux-mtd.infradead.org/faq/ubi.html UBI FAQ and HOWTO]

← Older revision	Revision as of 08:46, 26 November 2009
(No difference)

@@ Line 3: / Line 3: @@
 == Kernel support ==
-In order to get UBI and UBI GLUE driver working you need to enable them in kernel configuration. In kernel configuration choose '''"Device Drivers -> Memory Technology Device (MTD) support -> UBI - Unsorted block images"''' menu and enable '''"Enable UBI"''' and '''"Emulate MTD devices"''' options.
+In order to get UBI and UBI GLUE driver working you need to enable them in kernel configuration. In kernel configuration choose '''"Device Drivers -> Memory Technology Device (MTD) support -> UBI - Unsorted block images"''' menu and enable '''"Enable UBI"''' and '''"MTD devices emulation driver"''' options.
 <pre>
 ┌─────────────────────────────────── UBI - Unsorted block images ────────────────────────────────────┐
@@ Line 12: / Line 12: @@
 │ ┌────────────────────────────────────────────────────────────────────────────────────────────────┐ │
 │ │             <*> Enable UBI                                                                     │ │
-│ │             (4096) UBI wear-leveling threshold (NEW)                                           │ │
+│ │             (4096) UBI wear-leveling threshold                                                 │ │
-│ │             (1)   Percentage of reserved eraseblocks for bad eraseblocks handling (NEW)        │ │
+│ │             (1)   Percentage of reserved eraseblocks for bad eraseblocks handling              │ │
-│ │             [*]   Emulate MTD devices                                                          │ │
+│ │             <*>   MTD devices emulation driver (gluebi)                                        │ │
 │ │                   *** UBI debugging options ***                                                │ │
-│ │             [ ]   UBI debugging (NEW)                                                          │ │
+│ │             [ ]   UBI debugging                                                                │ │
 │ │                                                                                                │ │
 │ └────────────────────────────────────────────────────────────────────────────────────────────────┘ │
@@ Line 49: / Line 49: @@
 '''root=/dev/mtdblockY''' and add '''ubi.mtd=X,2048''' parameter, so the MTD partition containing the new UBI volume will be attached on kernel boot prior to root filesystem mount.
-== JFFS2 image eraseblock size ==
+== UBI logical eraseblock size and JFFS2 image eraseblock size ==
-UBI layer is using some part of NAND's ''physical'' erase block for it's own needs (e.g. bad blocks handling), therefore it provides a ''logical'' eraseblock for filesystem use. The logical eraseblock size is smaller than the physical, so when you construct the JFFS2 image, as described in section [[Linux_Development_for_XScale_modules#JFFS2_images|JFFS2 images]], you should set the {{parameter|eraseblock}} parameter to UBI's logical eraseblock size. <br>
+UBI layer is using some part of NAND's ''physical'' erase block for it's own needs (e.g. bad blocks handling), therefore it provides a ''logical'' eraseblock for filesystem use. The logical eraseblock size is smaller than the physical, so when you construct the JFFS2/UBIFS image, as described in section [[Linux_Development_for_XScale_modules#JFFS2_images|JFFS2 images]] and [[Linux_Development_for_XScale_modules#UBIFS_images|UBIFS images]], you should set the {{parameter|eraseblock}} (JFFS2) and {{parameter|leb-size}} (UBIFS) parameter to UBI's logical eraseblock size. <br>
 The UBI logical eraseblock size can be obtained by invoking the command:
 <pre>

← Older revision	Revision as of 12:31, 1 July 2009
(No difference)