Hi,
On 12/20/2012 02:26 PM, Peter Robinson wrote:
Hi Hans,
Second try!
> I'm very interested in fedora on arm, and as such I've started
> a "little" hobby project to get Fedora-arm up and running
> on allwinner a10 boards.
A number of us are interested in the A1x devices. I have a Cubieboard.
Lucky you, I'm on the pre-order list for the 2nd batch.
> After 2 weeks (mostly weekends) of fiddling and writing
> some kernel patches (more to follow). I've fedora-arm
> up and running nicely on an mk802-II "hdmi-stick", but it
> still needs some polishing before I can make images available.
>
> It also runs on the gooseberry board Spot gave me at
> Fudcon Paris, but the hdmi out of that board is having
> issues...
>
> My work is based on:
> -f18arm-latest-armhfp-xfce.tar.xz
> -https://github.com/linux-sunxi/linux-sunxi (3.4 branch)
> -https://github.com/linux-sunxi/u-boot-sunxi
>
> So all 100% open (not all upstream / mainline, but a group
> of people is working on that).
The initial upstream support has landed in 3.8 for the sunxi SoC
support. I'm not sure how complete it is.
Very incomplete it only does the timer core, etc. The dma
engine for example is still missing and thus anything
depending on it like usb / sata, etc.
There was someone working on
upstreaming the uboot support. I would be nice to find out the status
of that too.
I can ask on the linux-sunxi list.
> 1) Does anyone know a good place to host images, IE can I
> create a fedorahosted page for this and/or abuse
>
fedorapeople.org for this?
fedorapeople.org might be OK if you have enough space.
I don't think I've enough space though.
> 2) There are many A10 based devices (I've 3 more coming
> from china / hong kong), and all of them have different
> board-configs.
>
> The good news here is that the A10 boot setup involve
> something called a "fex" file, which is a config file which
> tells the kernel about which parts of the A10 are used on
> a board and which gpio pins are connected to what.
>
> So all a10 boards share a common kernel-build, they
> just need a different fex file, and a different u-boot.
>
> AFAIK for F-18 the same is done for some supported boards,
> where there is a single kernel, which gets configured through
> devicetree for specific boards. Ideally the A10 (sunxi)
> kernels should move over to devicetree too, but that will
> be a while, and won't really change the problem.
Yes, the mainline 3.8 support will have DT support I suspect.
Right, I think so too.
> So now we finally get to the question, how to deal with
> the situation where we can, and want to, support many
> boards, all with the same image, except for the need
> of a different u-boot and a small config file in /boot.
>
> One option would be to create 8 almost identical images,
> but that seems like a bad idea to me. What I'm currently
> thinking about is creating 1 4GB image for all A10 devices
> and configure it by default for the MK802 (version 1),
> but include compiled u-boot "images" and fex files
> under /boot, together with a small .sh script using dialog
> which allows the user to change the selected board-config.
>
> The user can then dd the image to an sdcard, mount it
> and then run the sh script to select the board model he
> wants to use it with. The sh script will be written so
> as to run on any architecture and distro.
I think that sounds reasonable, is there a means of specifying the fex
file in the uboot configuration? Then it might be just a matter of
specifying it and regenerating the uboot.scr file.
That might work, but uboot itself is board specific too...
> It could even be run on an actual A10 device, assuming the
> device is compatible with the MK802 revision 1, which most
> are (they need there own u-boot + fex to enable usage of
> 1G versus 512 MB ram, extra USB ports, etc.).
Yes, sounds fairly standard like most ARM variants based on a single SoC.
> So summarizing I'm looking for suggestions for:
> 1) Where to host Fedora-18 images for A10 based devices
> 2) How to deal with having board-specific u-boot + fex file
> without multiplying the number of images.
1) fedorapeople should be OK, or I have a host I can give you access
too if that doesn't work.
2) I think a simple script should be enough, with luck in a short
amount of time we should be able to support it all in the mainline
Fedora kernel with device tree.
I wouldn't count on the mainline kernel support getting there soon,
yes people are working on it. But the original sunxi code is
ugly as hell, so each part of it needs a lot of rework before
it can go upstream.
BTW does it need any binary firmwares for any HW support?
No firmware. There are the usual non firmware (iow running under
Linux) blobs for 3d / hardware-video decompression, etc.
But we get /dev/fb0 without any blobs, and I think I may even
be able to get a somewhat accelerated X running without the need
for blobs.
Also work is on its way to get an opensource stack with 3d support
running on the mali400, and the developer of this is using a10
as his reference platform.
Regards,
Hans