[maemo-developers] [maemo-developers] Modified initfs with onscreen boot menu

[From: Frantisek Dufka]

Jason Mills wrote:
> You -could- install the modified "bootprompt" initfs to the 770's flash
> -once-, and then ship releases of Sardine in such a manner that all you'd
> need to do is `dd` the various stages to high(er) numbered partitions on the
> card. 

Well, we have apt-get and instructions how to upgrade to Sardine from 
developer rootfs or regular IT2006 cloned to card so IMO this is not 
strictly needed.

>  
> If my math is right, you'd need an RS-MMC/MMCmobile card of at least 256 MB.
> Street cost of these is negligible compared to the cost of the 770.

JFFS2 filesystem in flash is compressed. You need at least twice the 
space on MMC to be comfortable. I made this mistake and now have 128 
partition on card almost full just by cloning clean IT2006 system.

>  
>  
>  
> That would give you:
>  xxx    12 MB (256,000,000 Bytes vs. 256 MB "loss")
>  
>  P0      -    DOS Partition Table Descriptior
>  P1p*   48 MB "Memory Card" fs
>  P2p     4 MB (Sardine initfs + scratch)
>  P3p   128 MB rootfs+userfs
>  P4E     -    DOS Extended Partition Table Descriptor
>  P5e    64 MB swapfs
>  ------------
>        256 MB

FAT as first partition for both swap and testing IT2006 functionality 
(usb storage, file manager) is another option to make rootfs bigger, 128 
is too small. Also initfs is curently in flash and it is not very useful 
to move it to card. It would need kernel and boot parameter 
modifications to boot initfs directly from card which is not trivial and 
would make the kernel bigger (ext2 and 3 are now modules). If this could 
be done it would be also good to have separate kernel on card (which is 
even harder).

BTW, since someone mentioned my initfs modification in 
http://maemo.org/maemowiki/SardineDistro I've added incomplete and 
unfinished guide to http://maemo.org/maemowiki/HowTo_BootRootFSFromMMC 
as alternative 2 so people will not flash developer rootfs needlessly. I 
plan to finish it when I have more time. Feel free to fix or expand it 
meanwhile.

Frantisek