MTD driver

MTD driver

[Subrahmanyam]

 Hi Stephen,

 Yes as you have said I shall setup a dedicated partition to give access a
 particular location in flash. We, have an Intel starta NOR flash which uses
 cfi command set driver, which basically i guess takes care of the erase
 operation too.  I have accessed the target through minicom tool, is this
 where i have to set up an additional partition?, can you suggest any site 
or
 procedure by which I can acheive setting up an additional partition.

 Yes, Thomas has suggested that i indeed use a filesystem, but how can I 
best
 achieve it! I mean the procedure to store data in a file.

 Thanks,
 Subrahmanyam.

>
> ----- Original Message ----- 
> From: "Stephan Linke" <Stephan.Linke@epygi.de>
> To: "Subrahmanyam" <subrahmanyam@navayuga.co.in>
> Cc: <linux-mtd@lists.infradead.org>
> Sent: Wednesday, December 08, 2004 03:33 PM
> Subject: RE: MTD driver
>
>
>> Hi,
>>
>> you may setup a dedicated partition that gives you access to the 
>> particular
>> location in the flash where you whant to place this data. Then you can 
>> use
>> normal open() read() write() and seek() functions to access what ever 
>> byte in
>> this partition. How to erass a block you can look up in one of the MTD 
>> tools.
>> (Only if you are using NAND flash you should not do it like this since 
>> bad block
>> handling whould be missing.)
>> But I aggree with Thomas. Best whould be to put it into a filesystem...
>>
>> Stephan
>>
>>
>>> -----Original Message-----
>>> From: linux-mtd-bounces@lists.infradead.org
>>> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Thomas
>>> Gleixner
>>> Sent: Mittwoch, 8. Dezember 2004 07:37
>>> To: Subrahmanyam
>>> Cc: linux-mtd@lists.infradead.org
>>> Subject: Re: MTD driver
>>>
>>>
>>> On Tue, 2004-12-07 at 09:16 +0530, Subrahmanyam wrote:
>>> >  Hi,
>>> >
>>> >  I need to provide an user interface/GUI wherein when a certain data
>>> > (string/key) is entered, it should basically store the key in the 
>>> > flash
>>> > (this basically happens during run time after the target has been
>>> identified
>>> > by the host).
>>> >
>>> > In the target we have a flash in which there is jffs2 file system and 
>>> > also
>>> > mtd drivers, since i need to store block oriented data, i am looking 
>>> > at the
>>> > possiblity of using mtd driver and storing data(key) in a particular
>>> > location in flash. How should i proceed in acheiving the same.
>>>
>>> Is there any good reason, why the key cannot be stored on the already
>>> available jffs2 filesystem ?
>>>
>>> tglx
>>>
>>>
>>>
>>> ______________________________________________________
>>> Linux MTD discussion mailing list
>>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>>>
>>
> 

RE: MTD driver

[Stephan Linke]

Hi Subrahmanyam,

to setup a separate partition you should have a look at the files in mtd/maps
directory.

The rest is simple as long as you whant to access it from user space. Just use
open/lseek/write (see man pages (2)) on either the filedescriptor of a regular
file or the device inode of the new flash partition.

If you need to access the data from within kernel code it is slightly different.
If you write to a flash partition you can find some ideas how to do it in
mtd/maps. About writing a file from within kernel code I can only tell you that
it is possible but I have no experience.

Stephan

> -----Original Message-----
> From: linux-mtd-bounces@lists.infradead.org
> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Subrahmanyam
> Sent: Donnerstag, 9. Dezember 2004 04:38
> To: linux-mtd@lists.infradead.org
> Subject: MTD driver
>
>
>  Hi Stephen,
>
>  Yes as you have said I shall setup a dedicated partition to give access a
>  particular location in flash. We, have an Intel starta NOR flash which uses
>  cfi command set driver, which basically i guess takes care of the erase
>  operation too.  I have accessed the target through minicom tool, is this
>  where i have to set up an additional partition?, can you suggest any site
> or
>  procedure by which I can acheive setting up an additional partition.
>
>  Yes, Thomas has suggested that i indeed use a filesystem, but how can I
> best
>  achieve it! I mean the procedure to store data in a file.
>
>  Thanks,
>  Subrahmanyam.
>
> >
> > ----- Original Message -----
> > From: "Stephan Linke" <Stephan.Linke@epygi.de>
> > To: "Subrahmanyam" <subrahmanyam@navayuga.co.in>
> > Cc: <linux-mtd@lists.infradead.org>
> > Sent: Wednesday, December 08, 2004 03:33 PM
> > Subject: RE: MTD driver
> >
> >
> >> Hi,
> >>
> >> you may setup a dedicated partition that gives you access to the
> >> particular
> >> location in the flash where you whant to place this data. Then you can
> >> use
> >> normal open() read() write() and seek() functions to access what ever
> >> byte in
> >> this partition. How to erass a block you can look up in one of the MTD
> >> tools.
> >> (Only if you are using NAND flash you should not do it like this since
> >> bad block
> >> handling whould be missing.)
> >> But I aggree with Thomas. Best whould be to put it into a filesystem...
> >>
> >> Stephan
> >>
> >>
> >>> -----Original Message-----
> >>> From: linux-mtd-bounces@lists.infradead.org
> >>> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Thomas
> >>> Gleixner
> >>> Sent: Mittwoch, 8. Dezember 2004 07:37
> >>> To: Subrahmanyam
> >>> Cc: linux-mtd@lists.infradead.org
> >>> Subject: Re: MTD driver
> >>>
> >>>
> >>> On Tue, 2004-12-07 at 09:16 +0530, Subrahmanyam wrote:
> >>> >  Hi,
> >>> >
> >>> >  I need to provide an user interface/GUI wherein when a certain data
> >>> > (string/key) is entered, it should basically store the key in the
> >>> > flash
> >>> > (this basically happens during run time after the target has been
> >>> identified
> >>> > by the host).
> >>> >
> >>> > In the target we have a flash in which there is jffs2 file system and
> >>> > also
> >>> > mtd drivers, since i need to store block oriented data, i am looking
> >>> > at the
> >>> > possiblity of using mtd driver and storing data(key) in a particular
> >>> > location in flash. How should i proceed in acheiving the same.
> >>>
> >>> Is there any good reason, why the key cannot be stored on the already
> >>> available jffs2 filesystem ?
> >>>
> >>> tglx
> >>>
> >>>
> >>>
> >>> ______________________________________________________
> >>> Linux MTD discussion mailing list
> >>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
> >>>
> >>
> >
>
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>

Re: MTD driver

[Subrahmanyam]

Hi Stephan,

Thanks for the help.

Inorder to create a new partition on the flash, can I use the "fis" commands 
when connected to the target through minicom tool.

As you have said to create a partition, a understanding of the files in 
mtd/maps directory is required, but there are so many files pertaining to
it, is it the file of the processor in the target, which in our case happens 
to be iop80321.

Please suggest how I can use the already existing jffs2 filesystem upon 
which I can create a file and store the key in a file. Apart from the file
system the other option would be to store the key in block oriented format 
i.e. by using fis from the redboot.

After storing the key in the flash, you have suggested that I can access the 
key using the device inode of the flash partition, how exactly can I obtain 
the device inode of a particular partition, could you please suggest the 
same.

Thanks,
Subrahmanyam.


----- Original Message ----- 
From: "Stephan Linke" <Stephan.Linke@epygi.de>
To: "Subrahmanyam" <subrahmanyam@navayuga.co.in>; 
<linux-mtd@lists.infradead.org>
Sent: Thursday, December 09, 2004 02:21 PM
Subject: RE: MTD driver


> Hi Subrahmanyam,
>
> to setup a separate partition you should have a look at the files in 
> mtd/maps
> directory.
>
> The rest is simple as long as you whant to access it from user space. Just 
> use
> open/lseek/write (see man pages (2)) on either the filedescriptor of a 
> regular
> file or the device inode of the new flash partition.
>
> If you need to access the data from within kernel code it is slightly 
> different.
> If you write to a flash partition you can find some ideas how to do it in
> mtd/maps. About writing a file from within kernel code I can only tell you 
> that
> it is possible but I have no experience.
>
> Stephan
>
>> -----Original Message-----
>> From: linux-mtd-bounces@lists.infradead.org
>> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Subrahmanyam
>> Sent: Donnerstag, 9. Dezember 2004 04:38
>> To: linux-mtd@lists.infradead.org
>> Subject: MTD driver
>>
>>
>>  Hi Stephen,
>>
>>  Yes as you have said I shall setup a dedicated partition to give access 
>> a
>>  particular location in flash. We, have an Intel starta NOR flash which 
>> uses
>>  cfi command set driver, which basically i guess takes care of the erase
>>  operation too.  I have accessed the target through minicom tool, is this
>>  where i have to set up an additional partition?, can you suggest any 
>> site
>> or
>>  procedure by which I can acheive setting up an additional partition.
>>
>>  Yes, Thomas has suggested that i indeed use a filesystem, but how can I
>> best
>>  achieve it! I mean the procedure to store data in a file.
>>
>>  Thanks,
>>  Subrahmanyam.
>>
>> >
>> > ----- Original Message -----
>> > From: "Stephan Linke" <Stephan.Linke@epygi.de>
>> > To: "Subrahmanyam" <subrahmanyam@navayuga.co.in>
>> > Cc: <linux-mtd@lists.infradead.org>
>> > Sent: Wednesday, December 08, 2004 03:33 PM
>> > Subject: RE: MTD driver
>> >
>> >
>> >> Hi,
>> >>
>> >> you may setup a dedicated partition that gives you access to the
>> >> particular
>> >> location in the flash where you whant to place this data. Then you can
>> >> use
>> >> normal open() read() write() and seek() functions to access what ever
>> >> byte in
>> >> this partition. How to erass a block you can look up in one of the MTD
>> >> tools.
>> >> (Only if you are using NAND flash you should not do it like this since
>> >> bad block
>> >> handling whould be missing.)
>> >> But I aggree with Thomas. Best whould be to put it into a 
>> >> filesystem...
>> >>
>> >> Stephan
>> >>
>> >>
>> >>> -----Original Message-----
>> >>> From: linux-mtd-bounces@lists.infradead.org
>> >>> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Thomas
>> >>> Gleixner
>> >>> Sent: Mittwoch, 8. Dezember 2004 07:37
>> >>> To: Subrahmanyam
>> >>> Cc: linux-mtd@lists.infradead.org
>> >>> Subject: Re: MTD driver
>> >>>
>> >>>
>> >>> On Tue, 2004-12-07 at 09:16 +0530, Subrahmanyam wrote:
>> >>> >  Hi,
>> >>> >
>> >>> >  I need to provide an user interface/GUI wherein when a certain 
>> >>> > data
>> >>> > (string/key) is entered, it should basically store the key in the
>> >>> > flash
>> >>> > (this basically happens during run time after the target has been
>> >>> identified
>> >>> > by the host).
>> >>> >
>> >>> > In the target we have a flash in which there is jffs2 file system 
>> >>> > and
>> >>> > also
>> >>> > mtd drivers, since i need to store block oriented data, i am 
>> >>> > looking
>> >>> > at the
>> >>> > possiblity of using mtd driver and storing data(key) in a 
>> >>> > particular
>> >>> > location in flash. How should i proceed in acheiving the same.
>> >>>
>> >>> Is there any good reason, why the key cannot be stored on the already
>> >>> available jffs2 filesystem ?
>> >>>
>> >>> tglx
>> >>>
>> >>>
>> >>>
>> >>> ______________________________________________________
>> >>> Linux MTD discussion mailing list
>> >>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>> >>>
>> >>
>> >
>>
>>
>> ______________________________________________________
>> Linux MTD discussion mailing list
>> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>>
> 

Re: MTD driver

[Thomas Gleixner]

On Thu, 2004-12-09 at 09:08 +0530, Subrahmanyam wrote:
>  Yes, Thomas has suggested that i indeed use a filesystem, but how can I 
> best
>  achieve it! I mean the procedure to store data in a file.

# echo "KEYSTRING" >/path/to/your/file

All programming languages provide functions to write to files.

# man 2 write

might be a good start. If this does not help you might try

http://www.amazon.com/exec/obidos/ASIN/0764570684/dangookin/104-4933924-3663106?creative=327641&camp=14573&link_code=as1

for further assistance.

tglx

Re: MTD driver

[Subrahmanyam]

Hi Thomas,

Can you suggest an approach to write into the flash either by using a file 
system or by using mtd drivers.
Yes, I am aware of writing data to a normal file but, but how is it possible 
to do in a jffs2 file system which is read only.

Please do suggest an approach.

Thanks,
Subrahmanyam.


----- Original Message ----- 
From: "Thomas Gleixner" <tglx@linutronix.de>
To: "Subrahmanyam" <subrahmanyam@navayuga.co.in>
Cc: <linux-mtd@lists.infradead.org>
Sent: Thursday, December 09, 2004 03:34 PM
Subject: Re: MTD driver


> On Thu, 2004-12-09 at 09:08 +0530, Subrahmanyam wrote:
>>  Yes, Thomas has suggested that i indeed use a filesystem, but how can I
>> best
>>  achieve it! I mean the procedure to store data in a file.
>
> # echo "KEYSTRING" >/path/to/your/file
>
> All programming languages provide functions to write to files.
>
> # man 2 write
>
> might be a good start. If this does not help you might try
>
> http://www.amazon.com/exec/obidos/ASIN/0764570684/dangookin/104-4933924-3663106?creative=327641&camp=14573&link_code=as1
>
> for further assistance.
>
> tglx
>
> 

MTD driver

[Subrahmanyam]

 Hi,

 I need to provide an user interface/GUI wherein when a certain data 
(string/key) is entered, it should basically store the key in the flash 
(this basically happens during run time after the target has been identified 
by the host).

In the target we have a flash in which there is jffs2 file system and also 
mtd drivers, since i need to store block oriented data, i am looking at the 
possiblity of using mtd driver and storing data(key) in a particular 
location in flash. How should i proceed in acheiving the same.

I will be thankful if you can best suggest an approach for acheiving the
same.

Thanks,
Subrahmanyam. 

Re: MTD driver

[Thomas Gleixner]

On Tue, 2004-12-07 at 09:16 +0530, Subrahmanyam wrote:
>  Hi,
> 
>  I need to provide an user interface/GUI wherein when a certain data 
> (string/key) is entered, it should basically store the key in the flash 
> (this basically happens during run time after the target has been identified 
> by the host).
> 
> In the target we have a flash in which there is jffs2 file system and also 
> mtd drivers, since i need to store block oriented data, i am looking at the 
> possiblity of using mtd driver and storing data(key) in a particular 
> location in flash. How should i proceed in acheiving the same.

Is there any good reason, why the key cannot be stored on the already
available jffs2 filesystem ?

tglx

RE: MTD driver

[Stephan Linke]

Hi,

you may setup a dedicated partition that gives you access to the particular
location in the flash where you whant to place this data. Then you can use
normal open() read() write() and seek() functions to access what ever byte in
this partition. How to erass a block you can look up in one of the MTD tools.
(Only if you are using NAND flash you should not do it like this since bad block
handling whould be missing.)
But I aggree with Thomas. Best whould be to put it into a filesystem...

Stephan


> -----Original Message-----
> From: linux-mtd-bounces@lists.infradead.org
> [mailto:linux-mtd-bounces@lists.infradead.org]On Behalf Of Thomas
> Gleixner
> Sent: Mittwoch, 8. Dezember 2004 07:37
> To: Subrahmanyam
> Cc: linux-mtd@lists.infradead.org
> Subject: Re: MTD driver
>
>
> On Tue, 2004-12-07 at 09:16 +0530, Subrahmanyam wrote:
> >  Hi,
> >
> >  I need to provide an user interface/GUI wherein when a certain data
> > (string/key) is entered, it should basically store the key in the flash
> > (this basically happens during run time after the target has been
> identified
> > by the host).
> >
> > In the target we have a flash in which there is jffs2 file system and also
> > mtd drivers, since i need to store block oriented data, i am looking at the
> > possiblity of using mtd driver and storing data(key) in a particular
> > location in flash. How should i proceed in acheiving the same.
>
> Is there any good reason, why the key cannot be stored on the already
> available jffs2 filesystem ?
>
> tglx
>
>
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/
>