How is mtdblock created?

Subodh Nijsure subodh at
Wed Feb 14 04:24:22 EST 2001

> Then mount the file system by:
> #mount -t jffs /dev/mtdblock0 /mnt/jffs (assuming /mnt/jffs exists, else
> make it).
> *** Making partitions with CFI flash and working with multiple banks
>     of FLASH:
> Unlike a "regular" block device, you cannot launch fdisk and create
> partitions on /dev/mtdblock0,1,2,3...
> (As far as I know) CFI flash partitions have to be created and
> compiled in the physmap.c file.

How are these /dev/mtdblock0...n devices created does one have to create 
them by hand are they are done as part of some module loading?

When I do modprobe physmap I get following output

sh-2.04# modprobe physmap
physmap flash device: size 0x00400000 at address 0x28000000
Call to cfi_probe received
cfi_probe_new_chip  buswidth is 4 size 0x00400000
Physically mapped flash: Found a coupled pair of CFI devices at location 0 in 16 bit mode
cfip->qry[0] = '', cfip->qry[1] = '', cfip->qry[2] = ''
Invalid CFI ident structure.
cfi.chipsize is zero. This is bad. cfi.cfiq.DevSize is 0
cfi_cfi_probe returned NULL
mtd: Giving out device 0 to Physically mapped flash
mtd: Giving out device 1 to SkyStream boot firmware
mtd: Giving out device 2 to SkyStream Flash Bank
sh-2.04# cat /proc/mtd
mtd0: 00400000 "Physically mapped flash"
mtd1: 00040000 "SkyStream boot firmware"
mtd2: 003a0000 "SkyStream Flash Bank"                                           

Now when I execute command od /dev/mtd0 to dump containts of the flash,
they match correctly. 

But I want to create the jffs file system (mkfs.jffs) and mount them 
but howto says I need /dev/mtdblockXX to do something like this,

	mount -t jffs /dev/mtdblock0 /mnt/jffs 

How is /dev/mtdblock0 created?


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