Linux Kernel MTD question

Linux Kernel MTD question

[JohnsonCheng]

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Dear All,

 

Just as I know, we can have many partitions for our flash if we turn on MTD
in Kernel. For example:

0x00000000-0x00040000:      u-boot

0x00040000-0x00100000:      kernel

0x00100000-0x00200000:      inirid1

0x00200000-0x00400000:      initrd2

 

How could I distribute my RootFS into initrd1 and initrd2?

In U-Boot command, bootcmd, I set it to "bootm 40000 100000". 40000 is
Kernel address, and 100000 is RootFS1 address. But where to set RootRS2
address?

 

Thanks,

Johnson Cheng

 


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Re: Linux Kernel MTD question

[Wolfgang Denk]

In message <20050821080936.DA55167F92@ozlabs.org> you wrote:
> 
> Just as I know, we can have many partitions for our flash if we turn on MTD
> in Kernel. For example:

Right.

> How could I distribute my RootFS into initrd1 and initrd2?

You cannot. The *root* filesystem is always just a single file system.

You can mount  additional  file  systems  on  top  of  the  directory
hierarchy  provided  by  your root file system, but this is something
completely different.

> In U-Boot command, bootcmd, I set it to "bootm 40000 100000". 40000 is
> Kernel address, and 100000 is RootFS1 address. But where to set RootRS2
> address?

There are several errors in this text.

First, the kernel download address 0x40000 = 256kB is  much  too  low
and can never work.

Second, the "100000" parameter is not a "RootFS1 address". It  is  the
start  address  of  a ramdisk image. This may or may not be your root
file system, and it is usually NOT the address as seen by the kernel.
And, 100000 = 1 MB is a much too low address and can never work.


And finally: all this has absolutely NOTHING to do with MTD partitions.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
Documentation is like sex: when it is good, it is  very,  very  good;
and when it is bad, it is better than nothing.         - Dick Brandon

RE: Linux Kernel MTD question

[JohnsonCheng]

Very Thanks for your reply.
I am sorry that this data is copied from Building Embedded Linux Systems
book.
Actually, the range of my flash is from 0xFF000000 to 0xFFFFFFFF. My
starting address of Kernel is 0xFF000000, and the starting address of
ramdisk image is FF200000, so the partitions is as following:
0xFF000000 - 0xFF1FFFFF		Kernel
0xFF200000 - 0xFF9FFFFF		RamDisk Image ( also my Root File System )

And I found my RootFS image is so big that waste many time while write it to
flash.
I hope I can use MTD to distribute it into two parts, Simple RootFS and
libraries, but I don't know how to implement it?

My CPU is MPC8241, and my kernel configure is base on Sandpoint_defconfig.

Thanks,
Johnson Cheng  

-----Original Message-----
From: linuxppc-embedded-bounces@ozlabs.org
[mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Wolfgang Denk
Sent: Monday, August 22, 2005 4:59 AM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question 

In message <20050821080936.DA55167F92@ozlabs.org> you wrote:
> 
> Just as I know, we can have many partitions for our flash if we turn on
MTD
> in Kernel. For example:

Right.

> How could I distribute my RootFS into initrd1 and initrd2?

You cannot. The *root* filesystem is always just a single file system.

You can mount  additional  file  systems  on  top  of  the  directory
hierarchy  provided  by  your root file system, but this is something
completely different.

> In U-Boot command, bootcmd, I set it to "bootm 40000 100000". 40000 is
> Kernel address, and 100000 is RootFS1 address. But where to set RootRS2
> address?

There are several errors in this text.

First, the kernel download address 0x40000 = 256kB is  much  too  low
and can never work.

Second, the "100000" parameter is not a "RootFS1 address". It  is  the
start  address  of  a ramdisk image. This may or may not be your root
file system, and it is usually NOT the address as seen by the kernel.
And, 100000 = 1 MB is a much too low address and can never work.


And finally: all this has absolutely NOTHING to do with MTD partitions.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
Documentation is like sex: when it is good, it is  very,  very  good;
and when it is bad, it is better than nothing.         - Dick Brandon
_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

Re: Linux Kernel MTD question

[Wolfgang Denk]

In message <20050822030032.4917442C7E@denx.de> you wrote:
>
> Actually, the range of my flash is from 0xFF000000 to 0xFFFFFFFF. My
> starting address of Kernel is 0xFF000000, and the starting address of
> ramdisk image is FF200000, so the partitions is as following:
> 0xFF000000 - 0xFF1FFFFF		Kernel
> 0xFF200000 - 0xFF9FFFFF		RamDisk Image ( also my Root File System )
> 
> And I found my RootFS image is so big that waste many time while write it to
> flash.

Then avoid writing it that often. Use  a  more  efficient  setup  for
developoment and test, like root file system mounted over NFS.

> I hope I can use MTD to distribute it into two parts, Simple RootFS and
> libraries, but I don't know how to implement it?

You can use MTD to provide an additional file system which  can  then
be mounted by one of your startup scripts. MTD configuration and file
system building is documented in the DULG, please see
http://www.denx.de/twiki/bin/view/DULG/Manual

It is not possible to  give  good  advice  how  to  split  data  into
separate  file  systems,  or  how  exactly  you  can mount it without
precise knowledge of your system and it's requirements. For  example,
do you use a SysV init with several run levels, or a simple setup for
example based on busybox? In the end this is something which you have
to design yourself.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
Let the programmers be many and the managers few -- then all will  be
productive.               -- Geoffrey James, "The Tao of Programming"

RE: Linux Kernel MTD question

[JohnsonCheng]

I have browsed the website, http://www.denx.de/twiki/bin/view/DULG/Manual.
For this example:
0x00000000-0x00060000 : "U-Boot"
0x00060000-0x00080000 : "Environment 1"
0x00080000-0x000A0000 : "Environment 2"
0x000A0000-0x000C0000 : "ASIC Images"
0x000C0000-0x001C0000 : "Linux Kernel"
0x001C0000-0x005C0000 : "Ramdisk Image"
0x005C0000-0x01000000 : "User Data"

How can I put the Environment variables or configurations in
0x00060000-0x00080000, or put User Data in 0x005C0000-0x1000000?
Use U-boot command? Or....

Best Regards,
Johnson Cheng


-----Original Message-----
From: linuxppc-embedded-bounces@ozlabs.org
[mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Wolfgang Denk
Sent: Monday, August 22, 2005 4:17 PM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question 

In message <20050822030032.4917442C7E@denx.de> you wrote:
>
> Actually, the range of my flash is from 0xFF000000 to 0xFFFFFFFF. My
> starting address of Kernel is 0xFF000000, and the starting address of
> ramdisk image is FF200000, so the partitions is as following:
> 0xFF000000 - 0xFF1FFFFF		Kernel
> 0xFF200000 - 0xFF9FFFFF		RamDisk Image ( also my Root File
System )
> 
> And I found my RootFS image is so big that waste many time while write it
to
> flash.

Then avoid writing it that often. Use  a  more  efficient  setup  for
developoment and test, like root file system mounted over NFS.

> I hope I can use MTD to distribute it into two parts, Simple RootFS and
> libraries, but I don't know how to implement it?

You can use MTD to provide an additional file system which  can  then
be mounted by one of your startup scripts. MTD configuration and file
system building is documented in the DULG, please see
http://www.denx.de/twiki/bin/view/DULG/Manual

It is not possible to  give  good  advice  how  to  split  data  into
separate  file  systems,  or  how  exactly  you  can mount it without
precise knowledge of your system and it's requirements. For  example,
do you use a SysV init with several run levels, or a simple setup for
example based on busybox? In the end this is something which you have
to design yourself.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
Let the programmers be many and the managers few -- then all will  be
productive.               -- Geoffrey James, "The Tao of Programming"
_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

Re: Linux Kernel MTD question

[Wolfgang Denk]

In message <20050822104924.214ED429CB@denx.de> you wrote:
> 
> How can I put the Environment variables or configurations in
> 0x00060000-0x00080000, or put User Data in 0x005C0000-0x1000000?
> Use U-boot command? Or....

It is up to you to define a memory map for your flash  device(s)  and
create  appropriate partitions for this map in Linux (and probably in
U-Boot, too, using the new "mtdparts" command).

Then you can use standard commands in U-Boot (erase, cp) and in Linux
(erase_all, cp) to store any data you likein your flash.

It is *your* design. *You* must create it.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
The IQ of the group is the lowest IQ of a member of the group divided
by the number of people in the group.

RE: Linux Kernel MTD question

[JohnsonCheng]

Yes. You are right. It's design by myself.
But I meet a problem. If I have three configuration files, A.conf, B.conf
and C.conf, then I hope save them in one of partitions of MTD,
0x005C0000-0x10000000.
Two questions:
1. How to build these configuration files into an image for U-boot with
mkimage?
2. In kernel, how to get these data? I use "mount /dev/mtd4 /mnt", but it
failed by block device required.

Thanks,
Johnson Cheng

-----Original Message-----
From: wd@denx.de [mailto:wd@denx.de] 
Sent: Monday, August 22, 2005 9:07 PM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question 

In message <20050822104924.214ED429CB@denx.de> you wrote:
> 
> How can I put the Environment variables or configurations in
> 0x00060000-0x00080000, or put User Data in 0x005C0000-0x1000000?
> Use U-boot command? Or....

It is up to you to define a memory map for your flash  device(s)  and
create  appropriate partitions for this map in Linux (and probably in
U-Boot, too, using the new "mtdparts" command).

Then you can use standard commands in U-Boot (erase, cp) and in Linux
(erase_all, cp) to store any data you likein your flash.

It is *your* design. *You* must create it.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
The IQ of the group is the lowest IQ of a member of the group divided
by the number of people in the group.

RE: Linux Kernel MTD question

[Robert P. J. Day]

On Sat, 23 Jul 2005, JohnsonCheng wrote:

> Yes. You are right. It's design by myself.
> But I meet a problem. If I have three configuration files, A.conf, B.conf
> and C.conf, then I hope save them in one of partitions of MTD,
> 0x005C0000-0x10000000.
> Two questions:
> 1. How to build these configuration files into an image for U-boot with
> mkimage?
> 2. In kernel, how to get these data? I use "mount /dev/mtd4 /mnt", but it
> failed by block device required.

for this second issue, you might try mounting the block device, which
is probably called /dev/mtdblock4 or something similar.

rday

RE: Linux Kernel MTD question

[JohnsonCheng]

When I want to turn on MTD with TQM8XXL, I can't find it in kernel 2.6.12.3.
I use "MTD\Mapping drivers for chip access\CFI Flash device in physical
memory map", it seems only one partition can be used.


Thanks,
Johnson Cheng


-----Original Message-----
From: linuxppc-embedded-bounces@ozlabs.org
[mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Wolfgang Denk
Sent: Monday, August 22, 2005 9:07 PM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question 

In message <20050822104924.214ED429CB@denx.de> you wrote:
> 
> How can I put the Environment variables or configurations in
> 0x00060000-0x00080000, or put User Data in 0x005C0000-0x1000000?
> Use U-boot command? Or....

It is up to you to define a memory map for your flash  device(s)  and
create  appropriate partitions for this map in Linux (and probably in
U-Boot, too, using the new "mtdparts" command).

Then you can use standard commands in U-Boot (erase, cp) and in Linux
(erase_all, cp) to store any data you likein your flash.

It is *your* design. *You* must create it.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
The IQ of the group is the lowest IQ of a member of the group divided
by the number of people in the group.
_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

RE: Linux Kernel MTD question

[JohnsonCheng]

It doesn't work, too. 
Error message: Invalid argument.

Thanks,
Johnson Cheng

-----Original Message-----
From: linuxppc-embedded-bounces@ozlabs.org
[mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Robert P. J. Day
Sent: Tuesday, August 23, 2005 11:24 AM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: RE: Linux Kernel MTD question 

On Sat, 23 Jul 2005, JohnsonCheng wrote:

> Yes. You are right. It's design by myself.
> But I meet a problem. If I have three configuration files, A.conf, B.conf
> and C.conf, then I hope save them in one of partitions of MTD,
> 0x005C0000-0x10000000.
> Two questions:
> 1. How to build these configuration files into an image for U-boot with
> mkimage?
> 2. In kernel, how to get these data? I use "mount /dev/mtd4 /mnt", but it
> failed by block device required.

for this second issue, you might try mounting the block device, which
is probably called /dev/mtdblock4 or something similar.

rday
_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

Re: Linux Kernel MTD question

[Wolfgang Denk]

In message <20050823053053.67D1A42AFE@denx.de> you wrote:
> When I want to turn on MTD with TQM8XXL, I can't find it in kernel 2.6.12.3.
> I use "MTD\Mapping drivers for chip access\CFI Flash device in physical
> memory map", it seems only one partition can be used.

There is no working support for TQM8xxL in the 2.6 kernel tree yet.

Please use the 2.4 kernel from our CVS server instead.

Best regards,

Wolfgang Denk

-- 
Software Engineering:  Embedded and Realtime Systems,  Embedded Linux
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd@denx.de
"And they told us, what they wanted... Was a sound  that  could  kill
some-one, from a distance."                               - Kate Bush

Re: Linux Kernel MTD question

[Ricardo Scop]

Hi Johnson,

On Tuesday 23 August 2005 02:31, JohnsonCheng wrote:
> It doesn't work, too.
> Error message: Invalid argument.
Well, do you have an mtdblock4 entry in /dev?

Also, you should specify your filesystem type to mount, like in:

mount -t jffs2 /dev/mtdblock4 /mnt

BTW, -t jffs2 is just an example.

HTH,

-Scop.

RE: Linux Kernel MTD question

[JohnsonCheng]

Dear Ricardo and Wolfgang,

Very thanks for your kindly support.
I am sorry I made a mistake.
Before you mount /dev/mtdblock4, you have to use mke2fs to format it.
Now I think my MTD function is almost ready, except write.
When I run "dd if=/dev/mtd1 of=kernel.img", it's OK.
But when I run "dd if=kernel.img of=/dev/mtd1", it's failed. No error
message printed, and the process time is shortly, cause Bad CRC.

Thanks,
Johnson Cheng

-----Original Message-----
From: linuxppc-embedded-bounces@ozlabs.org
[mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Ricardo Scop
Sent: Wednesday, August 24, 2005 3:17 AM
To: JohnsonCheng; 'Robert P. J. Day'
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question

Hi Johnson,

On Tuesday 23 August 2005 02:31, JohnsonCheng wrote:
> It doesn't work, too.
> Error message: Invalid argument.
Well, do you have an mtdblock4 entry in /dev?

Also, you should specify your filesystem type to mount, like in:

mount -t jffs2 /dev/mtdblock4 /mnt

BTW, -t jffs2 is just an example.

HTH,

-Scop.

_______________________________________________
Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-embedded

Re: Linux Kernel MTD question

[Alex Zeffertt]

Before doing a write to /dev/mtd1 try running 
~# eraseall /dev/mtd1

(eraseall is from the mtd-utils package.)

Alex


On Wed, 24 Aug 2005 13:02:31 +0800
"JohnsonCheng" <johnsoncheng@qnap.com.tw> wrote:

> Dear Ricardo and Wolfgang,
> 
> Very thanks for your kindly support.
> I am sorry I made a mistake.
> Before you mount /dev/mtdblock4, you have to use mke2fs to format it.
> Now I think my MTD function is almost ready, except write.
> When I run "dd if=/dev/mtd1 of=kernel.img", it's OK.
> But when I run "dd if=kernel.img of=/dev/mtd1", it's failed. No error
> message printed, and the process time is shortly, cause Bad CRC.
> 
> Thanks,
> Johnson Cheng
> 
> -----Original Message-----
> From: linuxppc-embedded-bounces@ozlabs.org
> [mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Ricardo Scop
> Sent: Wednesday, August 24, 2005 3:17 AM
> To: JohnsonCheng; 'Robert P. J. Day'
> Cc: linuxppc-embedded@ozlabs.org
> Subject: Re: Linux Kernel MTD question
> 
> Hi Johnson,
> 
> On Tuesday 23 August 2005 02:31, JohnsonCheng wrote:
> > It doesn't work, too.
> > Error message: Invalid argument.
> Well, do you have an mtdblock4 entry in /dev?
> 
> Also, you should specify your filesystem type to mount, like in:
> 
> mount -t jffs2 /dev/mtdblock4 /mnt
> 
> BTW, -t jffs2 is just an example.
> 
> HTH,
> 
> -Scop.
> 
> _______________________________________________
> Linuxppc-embedded mailing list
> Linuxppc-embedded@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
> 
> 
> _______________________________________________
> Linuxppc-embedded mailing list
> Linuxppc-embedded@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-embedded

RE: Linux Kernel MTD question

[JohnsonCheng]

Good idea. It works well.
The latest version of mtd utility for erase flash is flash_eraseall.

Thank you very much,
Johnson Cheng

-----Original Message-----
From: Alex Zeffertt [mailto:ajz@cambridgebroadband.com] 
Sent: Wednesday, August 24, 2005 4:50 PM
To: JohnsonCheng
Cc: linuxppc-embedded@ozlabs.org
Subject: Re: Linux Kernel MTD question

Before doing a write to /dev/mtd1 try running 
~# eraseall /dev/mtd1

(eraseall is from the mtd-utils package.)

Alex


On Wed, 24 Aug 2005 13:02:31 +0800
"JohnsonCheng" <johnsoncheng@qnap.com.tw> wrote:

> Dear Ricardo and Wolfgang,
> 
> Very thanks for your kindly support.
> I am sorry I made a mistake.
> Before you mount /dev/mtdblock4, you have to use mke2fs to format it.
> Now I think my MTD function is almost ready, except write.
> When I run "dd if=/dev/mtd1 of=kernel.img", it's OK.
> But when I run "dd if=kernel.img of=/dev/mtd1", it's failed. No error
> message printed, and the process time is shortly, cause Bad CRC.
> 
> Thanks,
> Johnson Cheng
> 
> -----Original Message-----
> From: linuxppc-embedded-bounces@ozlabs.org
> [mailto:linuxppc-embedded-bounces@ozlabs.org] On Behalf Of Ricardo Scop
> Sent: Wednesday, August 24, 2005 3:17 AM
> To: JohnsonCheng; 'Robert P. J. Day'
> Cc: linuxppc-embedded@ozlabs.org
> Subject: Re: Linux Kernel MTD question
> 
> Hi Johnson,
> 
> On Tuesday 23 August 2005 02:31, JohnsonCheng wrote:
> > It doesn't work, too.
> > Error message: Invalid argument.
> Well, do you have an mtdblock4 entry in /dev?
> 
> Also, you should specify your filesystem type to mount, like in:
> 
> mount -t jffs2 /dev/mtdblock4 /mnt
> 
> BTW, -t jffs2 is just an example.
> 
> HTH,
> 
> -Scop.
> 
> _______________________________________________
> Linuxppc-embedded mailing list
> Linuxppc-embedded@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-embedded
> 
> 
> _______________________________________________
> Linuxppc-embedded mailing list
> Linuxppc-embedded@ozlabs.org
> https://ozlabs.org/mailman/listinfo/linuxppc-embedded