From:  PLyttle <[email protected]>
Reply-To:  <[email protected]>
Date:  Monday, April 28, 2014 at 5:19 AM
To:  <[email protected]>
Subject:  Re: [beagleboard] Re: Booting Archlinux from microSD (again)

> Confusion galore...
> 
> When the board is powered on it boots from mmc1 (eMMC) as per SRM. It loads
> the uBoot files (including uEnv.txt) form eMMC.
I don¹t think this is correct. Looking at the default u-boot env, if an
SDCard is installed, it will load the uEnv.txt from the SDCard.

Regards,
John
> 
> when mmc1 does not hold a valid uBoot, or when the boot button is held down it
> boots from mmc0 (SD-card)
> 
> Most uBoot implementations work in reverse. When a valid /boot/zImage is
> availale on the SD-card it will default to booting Linux from SD, if not it
> will boot Linux from eMMC.
> 
> when a reboot is issued, the board boots as previously selected. (no need to
> press the boot button). When the board is shutdown it resets to default (mmc1)
> 
> It is pretty well documented in the SRM, but that is only valid for the uBoot
> phase
> 
> I makes a difference when you talk about uBoot booting or Linux booting.
> 
> LP
> 
> On Monday, April 28, 2014 10:42:01 AM UTC+2, William Hermans wrote:
>> John, what ? I have "booted" from multiple types of devices, and have never
>> had to hold down the power button. No modification, nothing. IN fact, I wrote
>> a blog post on netbooting Debian ( TFTP / NFS rootfs ) and had a comment come
>> back telling me this method worked for ARCH, and busybox as well.
>> 
>> 
>> Looking at the link Robert gave, those setting in a uEnv.txt file should
>> work. It probably would not hurt of the OP built his / her own uboot / MLO
>> too . . .
>> 
>> 
>> On Sun, Apr 27, 2014 at 11:28 PM, Don deJuan <[email protected]
>> <javascript:> > wrote:
>>>     
>>>  
>>> On 04/27/2014 11:09 PM, John Syn wrote:
>>>  
>>>  
>>>>  
>>>>  
>>>>  
>>>> 
>>>>  
>>>>  
>>>>  
>>>>   
>>>> From:  Don deJuan <[email protected] <javascript:> >
>>>>  Reply-To:  <[email protected] <javascript:> >
>>>>  Date:  Sunday, April 27, 2014 at 10:57 PM
>>>>  To:  <[email protected] <javascript:> >
>>>>  Subject:  Re: [beagleboard] Re: Booting Archlinux from microSD (again)
>>>>  
>>>>  
>>>> 
>>>>  
>>>>  
>>>>>  
>>>>>   
>>>>>  
>>>>> On 04/27/2014 10:16 PM, John Syn wrote:
>>>>>  
>>>>>  
>>>>>>  
>>>>>>  
>>>>>>  
>>>>>> 
>>>>>>  
>>>>>>  
>>>>>>  
>>>>>>   
>>>>>> From:  Doug <[email protected] <javascript:> >
>>>>>>  Reply-To:  <[email protected] <javascript:> >
>>>>>>  Date:  Sunday, April 27, 2014 at 9:52 PM
>>>>>>  To:  <[email protected] <javascript:> >
>>>>>>  Subject:  [beagleboard] Re: Booting Archlinux from microSD (again)
>>>>>>  
>>>>>>  
>>>>>> 
>>>>>>  
>>>>>>  
>>>>>>>  
>>>>>>> OK this does not work on Archlinux. Besides the fact Archlinux does not
>>>>>>> have initrd there must be some other issue holding it up. We are getting
>>>>>>> a serial connection hooked up to look at that.
>>>>>>>  
>>>>>>>  The answer about the only way was to remove a resistor is NOT a good
>>>>>>> answer. First of all it is not something you would do when distributing
>>>>>>> and image to be written on an SD card to a user. Hack your board so it
>>>>>>> works! No way.
>>>>>>>  
>>>>>>   
>>>>>> You asked for a solution that will work ³no matter what is on the eMMC².
>>>>>> If you have u-boot on the eMMC, BBB will use it, period. No script or
>>>>>> anything else for that matter will prevent this. Remove u-boot from the
>>>>>> eMMC and BBB will use u-boot from the SDCard. With SYS_BOOT2 high (Boot
>>>>>> not pressed), the boot sequence is MMC1 (eMMC), MMC0 (SDCard), UART0,
>>>>>> USB0. If SYS_BOOT2 is low (Boot button pressed) the boot sequence is
>>>>>> SPI0, MMC0, USB0, UART0.
>>>>>>  
>>>>>> 
>>>>>>  
>>>>>>  
>>>>>> Regards,
>>>>>>  
>>>>>> John
>>>>>>   
>>>>>>>  
>>>>>>> 
>>>>>>>  
>>>>>>>  I would like to get this fixed but an easy answer would be to have a
>>>>>>> script that does a one time run of zeroing the eMMC on first boot of
>>>>>>> ArchLinux on the SD card. We have no reason to use the eMMC card in our
>>>>>>> application. I wish there was a HW switch or jumper on the BBB to
>>>>>>> disable it. That would make things much easier.
>>>>>>>  
>>>>>>>  So please don't go hacking your board, just nuke the code on the eMMC.
>>>>>>> It will then boot happily from the SD card.
>>>>>>>  
>>>>>>>  Hopefully we will find a better way so we won't have to do that. I will
>>>>>>> report back in a few days with any progress.
>>>>>>>  
>>>>>>>  On Sunday, April 27, 2014 10:15:04 PM UTC-4, Doug wrote:
>>>>>>>  
>>>>>>> OK I asked this question before and I was never able to resolve it.
>>>>>>>  
>>>>>>>  I have an image (application) on microSD card that I want to
>>>>>>> distribute. It uses Archlinux.
>>>>>>>  
>>>>>>>  I don't want the user to have to play with boot directories pushing
>>>>>>> buttons or anything like that. I just want it to boot at power up.
>>>>>>>  
>>>>>>>  As long as a distribution (stock) image is on the eMMC it will not boot
>>>>>>> the SD card unless the boot button is held down at power up.
>>>>>>>  
>>>>>>>  I can get around this by wiping the eMMC but I do not want a user
>>>>>>> getting an image on SD and having to do that.
>>>>>>>  
>>>>>>>  Is there anything I can do on the SD card (boot record) to cause it to
>>>>>>> boot directly from SD regardless of what is on eMMC.
>>>>>>>  
>>>>>>>  Debian apparently has no problem with this. It seems to be an Archlinux
>>>>>>> issue.
>>>>>>>  
>>>>>>>  If therei s an answer please pass along the code or point me to it.
>>>>>>>  
>>>>>>>  
>>>>>>>  
>>>>>>>  -- 
>>>>>>>  For more options, visit http://beagleboard.org/discuss
>>>>>>>  --- 
>>>>>>>  You received this message because you are subscribed to the Google
>>>>>>> Groups "BeagleBoard" group.
>>>>>>>  To unsubscribe from this group and stop receiving emails from it, send
>>>>>>> an email to [email protected] <javascript:> .
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>>>>>>>  
>>>>>>   -- 
>>>>>>  For more options, visit http://beagleboard.org/discuss
>>>>>>  --- 
>>>>>>  You received this message because you are subscribed to the Google
>>>>>> Groups "BeagleBoard" group.
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>>>>>> an email to [email protected] <javascript:> .
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>>>>>>  
>>>>>  or why not just edit the uEnv.txt on the eMMC?
>>>>>  
>>>>>  
>>>>   
>>>> It is u-boot default environment that loads the uEnv.txt file. uEnv.txt
>>>> only augments the existing scripts already present in the u-boot
>>>> environment. Nothing that you do to the uEnv.txt will prevent BBB from
>>>> using the u-boot on the eMMC.
>>>>  
>>>> 
>>>>  
>>>>  
>>>> Regards,
>>>>  
>>>> John
>>>>   
>>>>>  
>>>>>  
>>>>> 
>>>>>  
>>>>>  
>>>>>  -- 
>>>>>  For more options, visit http://beagleboard.org/discuss
>>>>>  --- 
>>>>>  You received this message because you are subscribed to the Google Groups
>>>>> "BeagleBoard" group.
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>>>>> email to [email protected] <javascript:> .
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>>>>>  
>>>>   -- 
>>>>  For more options, visit http://beagleboard.org/discuss
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>>>>  
>>>  hmm strange
>>>  
>>> -- 
>>> For more options, visit http://beagleboard.org/discuss
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>> 
> 
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