[yocto] raspberrypi image questions

[Jack Mitchell]

On 05/09/2012 22:46, Paul Eggleton wrote:
> On Wednesday 05 September 2012 12:16:44 Gary Thomas wrote:
>> I just built Yocto/Poky for the raspberrypi, following the
>> recent thread on this list.  I noticed that the resulting SD
>> image is ~4GB, but most of that space seems to be unused:
>>
>>     $ ssh root at 192.168.1.150
>>     Warning: Permanently added '192.168.1.150' (RSA) to the list of known
>> hosts. root at 192.168.1.150's password:
>>     root at raspberrypi:~# df
>>     Filesystem           1K-blocks      Used Available Use% Mounted on
>>     /dev/root                57388     46754      7718  86% /
>>     none                     93964       156     93808   0% /dev
>>     /dev/mmcblk0p2           57388     46754      7718  86% /media/mmcblk0p2
>>     /dev/mmcblk0p1           19400      8928     10472  46% /media/mmcblk0p1
>>     tmpfs                    93964        56     93908   0% /var/volatile
>>     tmpfs                    93964         0     93964   0% /dev/shm
>>     tmpfs                    93964         0     93964   0% /media/ram
>>     root at raspberrypi:~# cat /proc/partitions
>>     major minor  #blocks  name
>>
>>      179        0    3977216 mmcblk0
>>      179        1      19456 mmcblk0p1
>>      179        2    3885056 mmcblk0p2
>>
>> Notice that the physical partition for /dev/mmcblk0p2 is huge but
>> the file system is only 57MB.
>>
>> How can I adjust my build and/or resize the file system to actually
>> use the rest of the SD card?
> I suspect a resize2fs call is needed in there. Since the SD card class in
> meta-raspberrypi was changed to use the actual ext2 rootfs image instead of
> creating a new one on the fly, this has become an issue. I would suggest filing
> the issue on the meta-raspberrypi github.
>
>> Also, is it possible to just build the SD image much like I do for
>> other devices like the BeagleBoard, albeit with different contents
>> in /boot?  Sloshing around 4GB images is rather painful, plus it
>> takes forever to DD it to the SD card.
> I must be missing something - do you want the rootfs larger or don't you? If
> it's expanded it will take up 4GB minus the boot partition size so you're into
> a large dd again...
>
> Cheers,
> Paul
>

I think what he means (or this is what I would like to see ) is a 
boot.tar.gz and a rootfs.tar.gz which can then be extracted straight 
onto the partitions? Hence only a ~40mb boot write and ~50mb rootfs 
write rather than a 4GB dd slog.