Towards an ARM system-building script

[Ganbold Tsagaankhuu]

On Tue, Oct 9, 2012 at 5:10 PM, Ganbold Tsagaankhuu <ganbold at gmail.com> wrote:
> On Tue, Oct 9, 2012 at 12:42 PM, Tim Kientzle <tim at kientzle.com> wrote:
>>
>> On Oct 8, 2012, at 9:07 PM, Ganbold Tsagaankhuu wrote:
>>
>>> On Mon, Sep 24, 2012 at 2:55 AM, Tim Kientzle <tim at kientzle.com> wrote:
>>>> On Sep 4, 2012, at 9:52 PM, Tim Kientzle wrote:
>>>>> On Sep 4, 2012, at 9:33 PM, Dave Cheney wrote:
>>>>>
>>>>>> Sorry to butt in on this discussion, but how feasible would it be to adapt this build script to the pandaboard. I understand there may be a config in svn similar to the beaglebone which may be applicable.
>>
>>>> I've made significant progress and would
>>>> appreciate any feedback:
>>>>
>>>>   github.com/kientzle/freebsd-beaglebone
>>>>
>>>> * PandaBoard:  I have a completely untested
>>>>    sketch.  Someone with a PandaBoard will need
>>>>    to work through the U-Boot configuration to make
>>>>    this work.
>>>
>>> I tried your script on PandaBoard ES.
>>> Basically it works with some modifications/considerations:
>>
>> Wonderful!  Thanks for trying it!
>>
>> Please send me any patches you used; I'll try
>> to incorporate them.
>>
>>> 1. PANDABOARD kernel config should be modified to use mmcsd card as root.
>>
>> Would anyone object to adding this line to FreeBSD SVN?
>>
>> # Boot device is 2nd slice on MMC/SD card
>> options         ROOTDEVNAME=\"ufs:mmcsd0s2\"
>>
>>
>>> 2. u-boot build complains about the board was configured to support THUMB mode
>>
>> Hmmm…  Not sure I understand this.
>>
>>> 3. Maybe there is need some more patches to have correct u-boot.bin,
>>> since it looks for uImage for instance
>>
>> There will certainly need to be some U-Boot patches.
>>
>> Perhaps Oleksandr can point us to the source he
>> used for that u-boot.bin?  If so, I can help fill in
>> the options so it can correctly chain ubldr.
>>
>>> 4. I didn't dig into ubldr/u-boot much, instead modified uEnv.txt to
>>> load kernel.bin from first partition which is FAT. I tried 8MB of FAT.
>
>
> Progress, seems like ubldr is working after patching u-boot.
> Here are the patches, uEnv.txt etc:
>
> http://people.freebsd.org/~ganbold/pandaboard/
>
> MLO is used from http://people.freebsd.org/~gonzo/pandaboard/

Strange, with ubldr Ethernet is not found, although kernel config is
the same as before.

Ganbold

>
> Ganbold
>
>
>
>>> 5. I used MLO, u-boot.bin from http://people.freebsd.org/~gonzo/pandaboard/
>>>
>>> So how does ubldr work? Can it load kernel.bin from second partition
>>> in case of PandaBoard?
>>
>> Yes, it can.  At heart, ubldr is the same as the FreeBSD
>> loader(8) that's used for i386/amd64 booting.  In particular,
>> it can load the kernel from UFS.
>>
>> The main difference between ubldr and loader(8)
>> is in how they access hardware:  loader(8) uses
>> the PC BIOS and ubldr talks to U-Boot to do low-level
>> device access.
>>
>> I think ubldr makes a lot of sense for BeagleBone and
>> probably PandaBoard.  I'm not sure it makes sense
>> for Raspberry Pi, though that's a different discussion.
>>
>> But ubldr requires that U-Boot be built with a few
>> non-standard options, so again we'll certainly have
>> to patch U-Boot to enable those options.
>>
>>
>> Tim
>>