[Raspberry Pi General] trevd:
[MENTION=5027322]GeekyDroid[/MENTION] Hi ... Should have mentioned that I threw together an HACKING document in the vendor repo :o

But Basically I've gone with on an 8GB sd

Number Name	Start End Size Type File system Flags
1 boot	512B 80.0MB 80.0MB primary fat16 lba
2 system	80.7MB 1000MB 920MB primary ext4
3 data	1000MB 7000MB 6000MB primary ext4
4 cache	7000MB 8000MB 999MB primary ext4

The sizes you can pick yourself boot is about 12MB at the moment. The system.img create by the build is and unsparsed ext4 image which is 512MB as specified in the device/broadcom/rpi/BoardConfig.mk . The actual system directory is ~215MB

My basic workflow for sdcard creation is to use a SDCard USB Adaptor. setup the partitions using parted and mount the boot partition. copy out/target/product/rpi/kernel out/target/product/rpi/ramdisk.img and the contents of out/target/product/rpi/bootloader to the mounted directory

then I used make_ext4 on the data and cache device nodes and then I just cat the out/target/product/rpi/kernel out/target/product/system.img to the system parted.

The hacking document explains it way better than I just have ... but I've typed it now so sod it :silly:

Obviously this method leaves gaps between the system and data partitions but for now I ain't to bothered. Recovery does work and there's a switch you can pass to the raspberry reboot which "tells" it to boot recovery ... i believe that's how their ( RPI Official ) noobs installer and like works. I've not got round to creating a updater-script for it yet

Once the system.img is "flashed" onto the sdcard and because of the nature of the task then you don't really need to create another one, I give mine a refresh every now and again just because I've been at it a couple of months now.

Once the PI is Booted as there is no OTG it brings up eth0 and runs netcfg eth0 dhcp as a late_start service and prints the ip address to the console. In my case the PI is connected to my home network so I then use adb over tcp for debugging fun! .. The bootanimation gets in the way of the printip now .. I should fix that .. obviously you can use a static one or whatever you like** The aforementioned services are specified in device/broadcom/rpi/init.bcm2708.rc

You can use mmp from within source directories to make and push whatever module your working on then adb restart to "hot restart" the framework.

you can also quickly replace the ramdisk.img kernel config.txt which has the resolution and kernel command line args by mounting using adb to mount /dev/block/mmcblk0p1 somewhere and just dropping in your replacements and rebooting .... saves constant pulling of the sdcard ; I read in various places that the sdcard slot isn't so robust but that's what you get for £30! :)

Hopefully that makes a little bit of sense ... I've only just picked the PI development backup after a month "off" ... I'm still a bit confused about GPU/GFX development in general and the fact that there's at least 3 maybe even 5 ways of allocating/locking/mapping the gpu memory and whether it even has to be mapped or whether "we" can just smash it using DMA isn't aiding in my rapid understanding of it .... I'll get there though.

Thanks

trevd

** I think eric anholt who is working on the vc4 drm/kms drivers and actually knows what he's doing wrt all the gfx fun is booting over NFS so is always an option see : http://anholt.livejournal.com/ for that work