[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[microblaze-uclinux] Re: [uClinux-dev] using flashw
Hi Anand,
anand_12 wrote:
> Thanks a lot for your clarification..well..thats precisely the information I was hunting for..I keep getting this
> error/message "can't allocate major number 31 to....."
> ..now I know why that is happening..well otherwise..I have verified the flash partitions..they are getting created properly..atleast thats what i assume from this kernel bootlog :
>
> Blkmem copyright 1998,1999 D. Jeff Dionne
> Blkmem copyright 1998 Kenneth Albanowski
> Blkmem 1 disk images:
> 0: 8014CA10-80188E0F [VIRTUAL 8014CA10-80188E0F] (RO)
Here the blkmem driver is taking responsibility for the romfs...
> uclinux[mtd]: RAM probe address=0x8014ca10 size=0x3d000
> uclinux[mtd]: root filesystem index=0
> MBVanilla flash probe(0xff000000,
> Amd/Fujitsu Extended Query Table v1.1 at 0x0040
> number of CFI chips: 1
> cfi_cmdset_0002: Disabling fast programming due to code brokenness.
> Creating 8 MTD partitions on "Flash":
> 0x00000000-0x00020000 : "Bootloader"
> 0x00020000-0x00040000 : "Bootargs"
> 0x00040000-0x00060000 : "MAC"
> 0x00080000-0x00100000 : "Config"
> 0x00060000-0x00080000 : "Spare"
> 0x00100000-0x00300000 : "Image"
> 0x00300000-0x00800000 : "JFFS2"
> 0x00000000-0x00800000 : "Flash"
> MBVanilla ram probe(0x8014ca10,249856,4): 3d000 at 8014ca10
> Creating 1 MTD partitions on "RAM":
> 0x00000000-0x0003d000 : "Romfs"
And here MTD is attempting to do the same (as well as create flash
partitions). This is bad.
> Can't allocate major number 31 for Memory Technology Devices.
And here is the MTD driver complaining about driver major number being
already taken (by blkmem).
You should just disable the blkmem driver in the kernel config, and
rebuild the kernel. I expect that will fix the problem immediately.
Arguments on blkmem vs MTD go something like this:
blkmem is simple, lightweight and it works. However, configuring it is
a mess of hacking on header files and so on. blkmem is slowly dying
(not sure if it's in 2.6)
MTD is also simple, and it works, with I think very slightly larger
overhead (code footprint). However, configuring it for a new platform
is a breeze. MTD is alive and well, widely used outside the NOMMU
community.
I switched the default microblaze configuration over to MTD about 12
months ago, and it is enabled by default in the mbvanilla_net platform.
Unless you have compelling reasons to do otherwise, I'd recommend you
just go with MTD.
Regards,
John
___________________________
microblaze-uclinux mailing list
microblaze-uclinux@itee.uq.edu.au
Project Home Page : http://www.itee.uq.edu.au/~jwilliams/mblaze-uclinux
Mailing List Archive : http://www.itee.uq.edu.au/~listarch/microblaze-uclinux/