[U-Boot] [U-BOOT PROBLEM] RAM loading RAMdisk addresses

[U-Boot] [U-BOOT PROBLEM] RAM loading RAMdisk addresses

[GRACE, ERWAN ** CTR **]

Hello all,

My name is Erwan Gr?ce, I'm French. Here's my issue : I had loaded the Flash memory of an electronic card with 2 RAMdisk which are supposed to be the same. However, when I checked the messages displayed on a screen at boot time, I observed that there were some differences between the 2 RAMdisk :

Messages displayed for the 1st RAMdisk :

## Booting image at ffb00000 ...
   Image Name:   Linux-2.6.10_mvlcge401-8560ads
   Image Type:   PowerPC Linux Kernel Image (gzip compressed)
   Data Size:    1662041 Bytes =  1.6 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Uncompressing Kernel Image ... OK
## Loading RAMDisk Image at fc100000 ...
   Image Name:   tcifl.ramdisk
   Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
   Data Size:    42466734 Bytes = 40.5 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Loading Ramdisk to 15780000, end 17fffdae ... OK

Messages displayed for the 2nd RAMdisk :

## Booting image at ffb00000 ...
   Image Name:   Linux-2.6.10_mvlcge401-8560ads
   Image Type:   PowerPC Linux Kernel Image (gzip compressed)
   Data Size:    1662041 Bytes =  1.6 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Uncompressing Kernel Image ... OK
## Loading RAMDisk Image at fc100000 ...
   Image Name:   tcifl.ramdisk
   Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
   Data Size:    42451540 Bytes = 40.5 MB
   Load Address: 00000000
   Entry Point:  00000000
   Verifying Checksum ... OK
   Loading Ramdisk to 15783000, end 17fff254 ... OK

As you can notice, the 2 RAMdisk seem to be different but I don't know why. I just observe that they have different size and they are not loaded at the same address in RAM memory. I precise that I didn't build this RAMdisk. Can someone help me to understand what is the root cause of these differences, please ? Thank you very much for your help.

Best regards,

Erwan Gr?ce

[U-Boot] [U-BOOT PROBLEM] RAM loading RAMdisk addresses

[Albert ARIBAUD]

Le 31/01/2011 14:43, GRACE, ERWAN (ERWAN)** CTR ** a ?crit :
> Hello all,
>
> My name is Erwan Gr?ce, I'm French. Here's my issue : I had loaded the Flash memory of an electronic card with 2 RAMdisk which are supposed to be the same. However, when I checked the messages displayed on a screen at boot time, I observed that there were some differences between the 2 RAMdisk :
>
> Messages displayed for the 1st RAMdisk :
>
> ## Booting image at ffb00000 ...
>     Image Name:   Linux-2.6.10_mvlcge401-8560ads
>     Image Type:   PowerPC Linux Kernel Image (gzip compressed)
>     Data Size:    1662041 Bytes =  1.6 MB
>     Load Address: 00000000
>     Entry Point:  00000000
>     Verifying Checksum ... OK
>     Uncompressing Kernel Image ... OK
> ## Loading RAMDisk Image at fc100000 ...
>     Image Name:   tcifl.ramdisk
>     Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
>     Data Size:    42466734 Bytes = 40.5 MB
>     Load Address: 00000000
>     Entry Point:  00000000
>     Verifying Checksum ... OK
>     Loading Ramdisk to 15780000, end 17fffdae ... OK
>
> Messages displayed for the 2nd RAMdisk :
>
> ## Booting image at ffb00000 ...
>     Image Name:   Linux-2.6.10_mvlcge401-8560ads
>     Image Type:   PowerPC Linux Kernel Image (gzip compressed)
>     Data Size:    1662041 Bytes =  1.6 MB
>     Load Address: 00000000
>     Entry Point:  00000000
>     Verifying Checksum ... OK
>     Uncompressing Kernel Image ... OK
> ## Loading RAMDisk Image at fc100000 ...
>     Image Name:   tcifl.ramdisk
>     Image Type:   PowerPC Linux RAMDisk Image (gzip compressed)
>     Data Size:    42451540 Bytes = 40.5 MB
>     Load Address: 00000000
>     Entry Point:  00000000
>     Verifying Checksum ... OK
>     Loading Ramdisk to 15783000, end 17fff254 ... OK
>
> As you can notice, the 2 RAMdisk seem to be different but I don't
> know  why. I just observe that they have different size and they are
> not loaded at the same address in RAM memory. I precise that I didn't
> build this RAMdisk. Can someone help me to understand what is the root
> cause of these differences, please ? Thank you very much for your help.

Hi Erwan,

I'm afraid this is absolutely not related to U-Boot. I can just offer 
the remark that iminfo shows your ramdisks differ in their rootfs part.

If you have any additional question, feel free to e-mail me -- in 
private, to avoid noise on the U-Boot list.

> Best regards,
>
> Erwan Gr?ce

Amicalement,
-- 
Albert.

[U-Boot] [U-BOOT PROBLEM] RAM loading RAMdisk addresses

[Wolfgang Denk]

Dear "GRACE, ERWAN (ERWAN)** CTR **",

In message <F427B25935CD0742BA694C0B6918F5701B705D87C7@FRMRSSXCHMBSE2.dc-m.alcatel-lucent.com> you wrote:
>
> My name is Erwan Gr?ce, I'm French. Here's my issue : I had loaded the Fl
> ash memory of an electronic card with 2 RAMdisk which are supposed to be th
> e same. However, when I checked the messages displayed on a screen at boot
> time, I observed that there were some differences between the 2 RAMdisk :

Please restrict your line length to some 70 characters or so.  Thanks.

> As you can notice, the 2 RAMdisk seem to be different but I don't know why.

The are obviously different, as they have different sizes.

We cannot answer the "why" as we have zero information about what you
did on that system, or why you even think they should be the same.
These are two different files.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
"Intelligence without character is a dangerous thing."   - G. Steinem

[U-Boot] [U-BOOT PROBLEM] RAM loading RAMdisk addresses

[Wolfgang Denk]

Dear "GRACE, ERWAN (ERWAN)** CTR **",

please make sure to keep the mailing list on Cc:

Also, please restrict your line length to some 70 characters or so.

In message <F427B25935CD0742BA694C0B6918F5701B70632924@FRMRSSXCHMBSE2.dc-m.alcatel-lucent.com> you wrote:
> 
> Thank you for your answer. I'd like to precise that the 2 RAMdisks
> weren't built from exactly the same set of files. There's a small
> difference between these RAMdisks as one of them was generated
> after replacing only one filewith another file which is supposed to
> be exactly the same as the first one. So, at the end of the day,
> these RAMdisks should have the same size but that isn't the case. I

No, they should not.  They should probably have the same content on a
file system level, but when erasing a file and replacing it by another
one (or even an identical copy) you will have other file system blocks
used, other inode and free block lists, etc.  In other words, the
binary images of the file systems will be different.  They will most
probably also compress to different sizes, then.

> precise that I'm not the person who generated these RAMdisks,
> that's why I try to understand why there's such a difference betw
> een them. Moreover, in the messages displayed on the screen when the

They are different images, with different sizes.

> board is booting, we can see that the addresses shown in the line
> "Loading RAMdisk to ..., end ... OK" are different. I'd like to
> know where these addressesare defined (in a configuration file? In

They are computed based on the ramdisk sizes (plus some rounding).
Given different ramdisk sizes you end up with different load
addresses.  There is no magic anywhere here.

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,     MD: Wolfgang Denk & Detlev Zundel
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Emotions are alien to me.  I'm a scientist.
	-- Spock, "This Side of Paradise", stardate 3417.3