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From: Christian Erhardt <christian.erhardt@mojo2k.de>
To: u-boot@lists.denx.de
Subject: [U-Boot] /proc/cpuinfo Revision field is 0000 on raspberry pi after booting with u-boot
Date: Sat, 13 Dec 2014 10:29:37 +0100	[thread overview]
Message-ID: <548C0701.90901@mojo2k.de> (raw)
In-Reply-To: <5486F2C5.1030908@mojo2k.de>

Hello,

just wanted to let you know, that i found the reason, why this is not 
working:

The raspberry pi passes the revision, serial number, mac address as 
parameters to the kernel during boot. When i start via u-boot, u-boot 
receives this parameters and does not pass them to the kernel. Thats why 
the revision field is empty.

Is there any way to pass parameters given to u-boot on to the kernel?

Regards

Christian


On 09.12.2014 14:01, Christian Erhardt wrote:
> Hello,
>
> i'm upcycling an old stereo amplifier and using an raspberry pi to do 
> this. Since i didn't want to unscrew the cover everytime i want to do 
> an update, i thought booting with u-boot from a secondary partition 
> would be a good idea. I'm using buildroot to create a customized 
> kernel / system (default raspberry 3.12.y with minor adjustments for 
> my wifi card).
>
> The kernel boots fine and the system is working. The issue is, that 
> when i do a 'cat /proc/cpuinfo' the Revision field is set to 0000. 
> When i boot the kernel directly, without u-boot, it reports 000e.
>
> The problem is, that the python gpio library is checking this revision 
> field to determine the right configuration. So the gpio stuff is not 
> working an complaining that my board is not a raspberry pi.
>
> It seems to me, that this issue is related to u-boot, but i have no 
> clue why this is happening and what i can do about it.
>
> If i can provide any more information, let me know.
>
> Regards
>
> Christian
> _______________________________________________
> U-Boot mailing list
> U-Boot at lists.denx.de
> http://lists.denx.de/mailman/listinfo/u-boot

      reply	other threads:[~2014-12-13  9:29 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-12-09 13:01 [U-Boot] /proc/cpuinfo Revision field is 0000 on raspberry pi after booting with u-boot Christian Erhardt
2014-12-13  9:29 ` Christian Erhardt [this message]

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