/dev/mtd* not there with latest MTD

/dev/mtd* not there with latest MTD

[Bernhard Priewasser]

Hello,

I'm using a modified 2.6.11 kernel running on a Hynix eval board with 
NOR flash. Using the existing MTD works fine (CONFIG_MTD_BLOCK and 
CONFIG_MTD_CHAR enabled), MTD is using a custom map and is running fine. 
U-Boot uses nfsroot.

Today I patched in the latest CVS snapshot (2005-10-10). Kernel is 
starting without problems (MTD debug level 3):

 > H720x-MTD probing 32bit FLASH
 > H720X: Found 2 x16 devices at 0x0 in 32-bit bank
 >  Intel/Sharp Extended Query Table at 0x0031
 > Using buffer write method
 > cfi_cmdset_0001: Erase suspend on write enabled
 > cmdlinepart partition parsing not available
 > Using builtin partition table
 > Creating 5 MTD partitions on "H720X":
 > 0x00000000-0x00080000 : "ArMon"
 > mtd: Giving out device 0 to ArMon
 > 0x00080000-0x000c0000 : "Env"
 > mtd: Giving out device 1 to Env
 > 0x000c0000-0x00240000 : "Kernel"
 > mtd: Giving out device 2 to Kernel
 > 0x00240000-0x00640000 : "Ramdisk"
 > mtd: Giving out device 3 to Ramdisk
 > 0x00640000-0x02000000 : "jffs2"
 > mtd: Giving out device 4 to jffs2

But: there is no /dev/mtd* or /dev/mtdblock* at all!
There are no changes to u-boot or some other kernel config, only the new 
MTD source.

Patching the kernel with 2005-06-21 CVS results in having only 
/dev/mtdblock*, but no /dev/mtd*!..... very confusing.

I would be glad if someone could help, I can provide more information if 
needed.

Regards,
Bernhard

Re: /dev/mtd* not there with latest MTD

[Todd Poynor]

Bernhard Priewasser wrote:

> But: there is no /dev/mtd* or /dev/mtdblock* at all!
> There are no changes to u-boot or some other kernel config, only the new 
> MTD source.
> 
> Patching the kernel with 2005-06-21 CVS results in having only 
> /dev/mtdblock*, but no /dev/mtd*!..... very confusing.

You're probably using devfs to automatically create device nodes, which 
is on its way out.  udev is the way recent 2.6 kernels do this 
http://www.kernel.org/pub/linux/utils/kernel/hotplug/udev.html

-- 
Todd

Re: /dev/mtd* not there with latest MTD

[Holger Schurig]

> But: there is no /dev/mtd* or /dev/mtdblock* at all!
> There are no changes to u-boot or some other kernel config, only the new
> MTD source.

This is no longer created by the CVS version MTD. Not wanting udev on my 
device (I was able to not use initrd's for years, why should I now begin?), I 
made some old-fanshiond mknod-style device files there. They have the same 
names as devfs without devfsd had, so my software just runs fine.

Re: /dev/mtd* not there with latest MTD

[Bernhard Priewasser]

Oh...
http://lists.infradead.org/pipermail/linux-mtd/2005-August/013385.html
Sorry, my fault.

Bernhard

Re: /dev/mtd* not there with latest MTD

[Bernhard Priewasser]

> I made some old-fanshiond mknod-style device files there. They have the
> same names as devfs without devfsd had, so my software just runs fine.

/dev/mtdblockX works fine, but /dev/mtdX NOT.

Did you only create mtdblocks or mtds too?
Older MTD creates /dev/mtdX with minor numbers X*2; running flash_erase 
(for example) works fine.
Not so with same kernel, but latest CVS: creating exactly the same 
/dev/mtdX as mtdchar.c would do (e.g. older MTD would do), I cannot 
operate the flash properly. flash_erase results in an CFI error:

 > > flash_erase /dev/mtd4
 > Erase Total 1 Units
 > Performing Flash Erase of length 262144 at offset 0x0
 > H720X: block erase error: (status timeout)
 > MTD Erase failure: Input/output error
 > H720X: Waiting for chip to be ready timed out. Status 300080

Hm...

Regards,
Bernhard