User's Manual

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8.2.2 Formatting YAFFS Partitions

All file systems need to be formatted before they can be mounted. Because YAFFS was designed from the

ground up to work with embedded flash technologies, it understands an 'erased' flash device to be both

formatted and empty. To prepare your partition for mounting, simply use LogicLoader's 'erase' command to

erase the area of flash where the partition is to be located.

Using the example partition scheme in the “Developing a Partition Scheme” section, above, the partitions

could be prepared for initial use by erasing the regions of the flash device spanned by them.

For example (LH7A404-11 system address used): losh> erase 0x000C0000 0x00800000

losh > erase 0x00900000 0x00400000

Warning: Erasing flash blocks that will be used for YAFFS partitions will erase everything in those areas of

flash. It is not required to format the partition every time the device is rebooted. The partition should only

be formatted when an entirely new YAFFS partition is created, or when the data on a stored partition needs

to be completely erased.

8.2.3 Adding YAFFS Type Partitions

LogicLoader maintains a partition table in RAM. Before a YAFFS partition can be mounted, it must be

added to the partition table. To do this, the 'add-yaffs' command is used. The 'add-yaffs' command takes the

following arguments:

• <name> a unique string which identifies the partition

• <type> type of flash device the partition resides on

• <start> the physical starting address of the partition

• <length> the length (in bytes) of the partition

Continuing with the example partitions above, LogicLoader can be instructed to add the partitions by

executing the commands as shown below (LH7A404-11 system address used):

losh> add-yaffs boot nor 0x000C0000 0x00800000

losh> add-yaffs data nor 0x00900000 0x00400000

Note: The above steps must be performed every time LogicLoader boots. Because LogicLoader keeps the

partition table in RAM, the existence and locations of YAFFS partitions does not persist across resets or

power cycles.

8.2.4 Mounting the Partition

To mount a partition in the partition table, the 'mount' command is used. That command takes the following

arguments:

• <fstype> the type of filesystem being mounted (‘yaffs’ here)

• [drive addr] not used when mounting a YAFFS partition

• <point> the name of the YAFFS partition

For example:

losh> mount yaffs /boot