Re: /dev/flash and MTD

Re: /dev/flash and MTD

[diekema_jon]

> To enable MTD on a board, do we still need /dev/flash?

No.

> In other words, is there any relationship between /dev/flash and
> MTD? I found that only on Denx distribution of 2.4.4 there is such a
> device '/dev/flash'. Thanks.

The /dev/flash device entries use a stand alone flash driver that
isn't part of MTD.

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Re: /dev/flash and MTD

[Wolfgang Denk]

In message <3D540B52.8080709@redswitch.com> you wrote:
> To enable MTD on a board, do we still need /dev/flash? In other words,

No, this is not needed for MTD.  It's  an  alternative  interface  to
access  flash  memory; we mostly keep it for compatibility with older
projects, and because it provides some nice features like allowing to
mmap() the flash (RO).

> is there any relationship between /dev/flash and MTD? I found that only
> on Denx distribution of 2.4.4 there is such a device '/dev/flash'. Thanks.

These are two independend solutions to the task of  providing  access
to  flash  memory;  MTD is superior when you also need a block device
interface.

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
When you say "I wrote a program that crashed  Windows",  people  just
stare  at you blankly and say "Hey, I got those with the system, *for
free*".        - Linus Torvalds in <3itc77$9lj@ninurta.fer.uni-lj.si>

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Re: /dev/flash and MTD

[Wolfgang Denk]

Dear Shawn,

in message <3D54526C.80703@redswitch.com> you wrote:
>
> WINDOW_SIZE. What does this difference mean? If I know the physical
> start address of flash memory and the size, is there a generic map
> driver available to do the probing? My general question is "do we need a
> MTD map driver for each board, especially for those custom boards?".

Actually we don't. Set  the  config  option  CONFIG_MTD_CMDLINE_PARTS
which  allows  the  use  of  a generic mapping driver and passing the
partitioning info from the command line.

Wolfgang Denk

--
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-4596-87  Fax: (+49)-8142-4596-88  Email: wd@denx.de
Do not follow where the path may lead....go instead where there is no
path and leave a trail.

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