linux boot sequence

linux boot sequence

[Rami WEHBI]

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Hi all,
 
    I am using the ppc405 and I would like to know, how does linux on this architect detect the available memory size in details !!!
        is it a parameter passed to linux at startup by the boot loader ??
        is it an automatic detection ?? what are the steps to accomplish this job then ???
 
Best regards to all,
 
Rami
 



Rami WEHBI 	
Recherche & Développement 	
Tél :	 +33 2 36 56 86 00	
Fax :	 +33 2 36 56 86 01	
www.wirecom-tech.com	

  <http://www.wirecom-tech.com> 	

WIRECOM Technologies 
135, Rue Jacques Charles
45166 Olivet
	

  	

  	


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linux boot sequence

[Siva Prasad]

Well!... You can pass the size as part of the OF memory=3D<>.

Typically your boot loader should detect the amount of memory on the
system and update the OF dtb to reflect the available memory.

You may also tweak the kernel yourself to autodetect, instead of reading
from the OF. How ever, I would recommend the previous approach.

- Siva


Date: Fri, 11 Jul 2008 08:34:54 +0200
From: "Rami WEHBI" <rwehbi@wirecom-tech.com>
Subject: linux boot sequence
To: <linuxppc-embedded@ozlabs.org>
Message-ID:
=09
<D3C541E264C021479BFB60B3B790C0FB497014@etoilenoire.STARWARS.local>
Content-Type: text/plain; charset=3D"iso-8859-1"


Hi all,
=20
    I am using the ppc405 and I would like to know, how does linux on
this architect detect the available memory size in details !!!
        is it a parameter passed to linux at startup by the boot loader
??
        is it an automatic detection ?? what are the steps to accomplish
this job then ???
=20
Best regards to all,
=20
Rami
=20



Rami WEHBI =09
Recherche & D?veloppement =09
T?l :	 +33 2 36 56 86 00=09
Fax :	 +33 2 36 56 86 01=09
www.wirecom-tech.com=09

  <http://www.wirecom-tech.com> =09

WIRECOM Technologies=20
135, Rue Jacques Charles
45166 Olivet
=09

Re: linux boot sequence

[Wolfgang Denk]

In message <D3C541E264C021479BFB60B3B790C0FB497014@etoilenoire.STARWARS.local> you wrote:
> 
>     I am using the ppc405 and I would like to know, how does linux on
> this architect detect the available memory size in details !!!
>         is it a parameter passed to linux at startup by the boot loader
> ??

Yes.


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@denx.de
The more complex the mind, the greater the need for the simplicity of
play.
	-- Kirk, "Shore Leave", stardate 3025.8

RE: linux boot sequence

[Siva Prasad]

Rami,

Please make sure to copy the list as well.

OF - Open firmware. I am not sure which version of Linux kernel you are =
using, and which boot loader. Lately it is all OF based, however it is =
supported in the form of device tree blob/structure. For more =
information read booting-without-of.txt in Documentation/powerpc.

U-Boot updates the detected memory in the dtb you loaded, so that when =
kernel reads it, correct information is provided.

There is no auto-detect option in kernel. You need to write your own =
code at the exact location it needs to identify the size of memory. =
Typically this is passed to the kernel either through DTB or kernel =
arguments.

Good Luck.

- Siva




-----Original Message-----
From: Rami WEHBI [mailto:rwehbi@wirecom-tech.com]=20
Sent: Monday, July 14, 2008 11:47 PM
To: Siva Prasad
Subject: RE: linux boot sequence


 what is the OF dtb ??? And how does the bootloader update it ???

 How can I do to set the autodetect option in the kernel ???


Best Regards,
Rami,



-----Message d'origine-----
De : Siva Prasad [mailto:sprasad@bivio.net]=20
Envoy=E9 : vendredi 11 juillet 2008 23:01
=C0 : Rami WEHBI
Cc : linuxppc-embedded@ozlabs.org
Objet : linux boot sequence


Well!... You can pass the size as part of the OF memory=3D<>.

Typically your boot loader should detect the amount of memory on the =
system and update the OF dtb to reflect the available memory.

You may also tweak the kernel yourself to autodetect, instead of reading =
from the OF. How ever, I would recommend the previous approach.

- Siva


Date: Fri, 11 Jul 2008 08:34:54 +0200
From: "Rami WEHBI" <rwehbi@wirecom-tech.com>
Subject: linux boot sequence
To: <linuxppc-embedded@ozlabs.org>
Message-ID:
=09
<D3C541E264C021479BFB60B3B790C0FB497014@etoilenoire.STARWARS.local>
Content-Type: text/plain; charset=3D"iso-8859-1"


Hi all,
=20
    I am using the ppc405 and I would like to know, how does linux on =
this architect detect the available memory size in details !!!
        is it a parameter passed to linux at startup by the boot loader =
??
        is it an automatic detection ?? what are the steps to accomplish =
this job then ???
=20
Best regards to all,
=20
Rami
=20



Rami WEHBI =09
Recherche & D?veloppement =09
T?l :	 +33 2 36 56 86 00=09
Fax :	 +33 2 36 56 86 01=09
www.wirecom-tech.com=09

  <http://www.wirecom-tech.com> =09

WIRECOM Technologies
135, Rue Jacques Charles
45166 Olivet
=09

RE: linux boot sequence

[Rami WEHBI]

Hello Siva,

I am using the 2.6.23 kernel and the target is the ppc405.=20

Using the booting-without-of.txt, and in searching in the kernel code I =
found that the devices_info are passed as parameters (memory size is the =
parameter I am searching for) by calling the function =
"find_bootinfo(void)" in /arch/ppc/kernel/setup.c
This function initializes send the pointer to linux on the device info =
as following (line 345):

		Rec =3D (struct bi_record *) =
_ALIGN((ulong)__bss_start+(1<<20)-1,(1<<20));

What is this address stand for ???=20


Rami,



-----Message d'origine-----
De : linuxppc-embedded-bounces+rami.wehbi=3Dwirecom-tech.com@ozlabs.org =
[mailto:linuxppc-embedded-bounces+rami.wehbi=3Dwirecom-tech.com@ozlabs.or=
g] De la part de Siva Prasad
Envoy=E9 : mercredi 16 juillet 2008 20:46
=C0 : Rami WEHBI
Cc : linuxppc-embedded@ozlabs.org
Objet : RE: linux boot sequence

Rami,

Please make sure to copy the list as well.

OF - Open firmware. I am not sure which version of Linux kernel you are =
using, and which boot loader. Lately it is all OF based, however it is =
supported in the form of device tree blob/structure. For more =
information read booting-without-of.txt in Documentation/powerpc.

U-Boot updates the detected memory in the dtb you loaded, so that when =
kernel reads it, correct information is provided.

There is no auto-detect option in kernel. You need to write your own =
code at the exact location it needs to identify the size of memory. =
Typically this is passed to the kernel either through DTB or kernel =
arguments.

Good Luck.

- Siva




-----Original Message-----
From: Rami WEHBI [mailto:rwehbi@wirecom-tech.com]
Sent: Monday, July 14, 2008 11:47 PM
To: Siva Prasad
Subject: RE: linux boot sequence


 what is the OF dtb ??? And how does the bootloader update it ???

 How can I do to set the autodetect option in the kernel ???


Best Regards,
Rami,



-----Message d'origine-----
De : Siva Prasad [mailto:sprasad@bivio.net]=20
Envoy=E9 : vendredi 11 juillet 2008 23:01
=C0 : Rami WEHBI
Cc : linuxppc-embedded@ozlabs.org
Objet : linux boot sequence


Well!... You can pass the size as part of the OF memory=3D<>.

Typically your boot loader should detect the amount of memory on the =
system and update the OF dtb to reflect the available memory.

You may also tweak the kernel yourself to autodetect, instead of reading =
from the OF. How ever, I would recommend the previous approach.

- Siva


Date: Fri, 11 Jul 2008 08:34:54 +0200
From: "Rami WEHBI" <rwehbi@wirecom-tech.com>
Subject: linux boot sequence
To: <linuxppc-embedded@ozlabs.org>
Message-ID:
=09
<D3C541E264C021479BFB60B3B790C0FB497014@etoilenoire.STARWARS.local>
Content-Type: text/plain; charset=3D"iso-8859-1"


Hi all,
=20
    I am using the ppc405 and I would like to know, how does linux on =
this architect detect the available memory size in details !!!
        is it a parameter passed to linux at startup by the boot loader =
??
        is it an automatic detection ?? what are the steps to accomplish =
this job then ???
=20
Best regards to all,
=20
Rami
=20



Rami WEHBI =09
Recherche & D?veloppement =09
T?l :	 +33 2 36 56 86 00=09
Fax :	 +33 2 36 56 86 01=09
www.wirecom-tech.com=09

  <http://www.wirecom-tech.com> =09

WIRECOM Technologies
135, Rue Jacques Charles
45166 Olivet
=09






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

RE: linux boot sequence

[Siva Prasad]

Rami,

I am copy pasting a portion of my dts file. Here I am mentioning 2GB of =
memory. However, U-Boot can update this automatically, as u-boot is OF =
aware.

        memory {
                device_type =3D "memory";
                reg =3D <00000000 80000000>;
        };

What is the boot loader you are using?

With the latest kernels you should be on arch/powerpc, not arch/ppc. I =
am not sure about the support for your PPC405 in powerpc.

- Siva



-----Original Message-----
From: Rami WEHBI [mailto:rwehbi@wirecom-tech.com]=20
Sent: Thursday, July 17, 2008 5:42 AM
To: Siva Prasad
Cc: linuxppc-embedded@ozlabs.org
Subject: RE: linux boot sequence

Hello Siva,

I am using the 2.6.23 kernel and the target is the ppc405.=20

Using the booting-without-of.txt, and in searching in the kernel code I =
found that the devices_info are passed as parameters (memory size is the =
parameter I am searching for) by calling the function =
"find_bootinfo(void)" in /arch/ppc/kernel/setup.c
This function initializes send the pointer to linux on the device info =
as following (line 345):

		Rec =3D (struct bi_record *) =
_ALIGN((ulong)__bss_start+(1<<20)-1,(1<<20));

What is this address stand for ???=20


Rami,



-----Message d'origine-----
De : linuxppc-embedded-bounces+rami.wehbi=3Dwirecom-tech.com@ozlabs.org =
[mailto:linuxppc-embedded-bounces+rami.wehbi=3Dwirecom-tech.com@ozlabs.or=
g] De la part de Siva Prasad
Envoy=E9 : mercredi 16 juillet 2008 20:46
=C0 : Rami WEHBI
Cc : linuxppc-embedded@ozlabs.org
Objet : RE: linux boot sequence

Rami,

Please make sure to copy the list as well.

OF - Open firmware. I am not sure which version of Linux kernel you are =
using, and which boot loader. Lately it is all OF based, however it is =
supported in the form of device tree blob/structure. For more =
information read booting-without-of.txt in Documentation/powerpc.

U-Boot updates the detected memory in the dtb you loaded, so that when =
kernel reads it, correct information is provided.

There is no auto-detect option in kernel. You need to write your own =
code at the exact location it needs to identify the size of memory. =
Typically this is passed to the kernel either through DTB or kernel =
arguments.

Good Luck.

- Siva




-----Original Message-----
From: Rami WEHBI [mailto:rwehbi@wirecom-tech.com]
Sent: Monday, July 14, 2008 11:47 PM
To: Siva Prasad
Subject: RE: linux boot sequence


 what is the OF dtb ??? And how does the bootloader update it ???

 How can I do to set the autodetect option in the kernel ???


Best Regards,
Rami,



-----Message d'origine-----
De : Siva Prasad [mailto:sprasad@bivio.net]=20
Envoy=E9 : vendredi 11 juillet 2008 23:01
=C0 : Rami WEHBI
Cc : linuxppc-embedded@ozlabs.org
Objet : linux boot sequence


Well!... You can pass the size as part of the OF memory=3D<>.

Typically your boot loader should detect the amount of memory on the =
system and update the OF dtb to reflect the available memory.

You may also tweak the kernel yourself to autodetect, instead of reading =
from the OF. How ever, I would recommend the previous approach.

- Siva


Date: Fri, 11 Jul 2008 08:34:54 +0200
From: "Rami WEHBI" <rwehbi@wirecom-tech.com>
Subject: linux boot sequence
To: <linuxppc-embedded@ozlabs.org>
Message-ID:
=09
<D3C541E264C021479BFB60B3B790C0FB497014@etoilenoire.STARWARS.local>
Content-Type: text/plain; charset=3D"iso-8859-1"


Hi all,
=20
    I am using the ppc405 and I would like to know, how does linux on =
this architect detect the available memory size in details !!!
        is it a parameter passed to linux at startup by the boot loader =
??
        is it an automatic detection ?? what are the steps to accomplish =
this job then ???
=20
Best regards to all,
=20
Rami
=20



Rami WEHBI =09
Recherche & D?veloppement =09
T?l :	 +33 2 36 56 86 00=09
Fax :	 +33 2 36 56 86 01=09
www.wirecom-tech.com=09

  <http://www.wirecom-tech.com> =09

WIRECOM Technologies
135, Rue Jacques Charles
45166 Olivet
=09






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Linuxppc-embedded mailing list
Linuxppc-embedded@ozlabs.org
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