Need Guidance on an AMD Geode LX800 System

ambad4u · Last edited by ambad4u on Sun Mar 22, 2015 11:07 am; edited 1 time in total

Greetings to All,

First of all, I am not sure if this is in the right forum section as I am torn between selecting "Installing Gentoo", "Kernel & Hardware" and "Gentoo on Alternative Architecture".

anyways, I have an AMD Geode LX800 System and is very similar to that of Alix SBC's.
to enumerate what I have:
[*] AMD Geode LX800 (i586 variant processor)
[*] CS5536 Companion Chipset
[*] Gigabit LAN RTL-8110SC/8169SC
[*] 512Mb RAM (removable)
[*] onboard VGA, sound, 3x USB, normal internal IDE header + compact flash card slot
[*] 512Mb CF Card [will be using the 120Gb 2.5" ide hdd instead]
[*] have 8Gb usb flash drive (just in case) [will be using the 120Gb 2.5" ide hdd instead]
to have a good idea how it looks like, google these: "tr2350 futro a220"

downloaded the 486 iso 'install-x86-minimal-20150310.iso', used unetbootin to transder the iso to usb, booted and it detected all things needed.
I am leaning towards installing Gentoo on this little marvel of yesteryear's

, but I have some 'minor' problem(s) in my current device setup.

The Limitations:
[*] can't use regular HDD's and I'm limited into using the 512Mb CF card and probably with the 8Gb flash drive (512Mb + 8Gb combo) [cancelled]
[*] can't upgrade/buy another CF card, too expensive[cancelled]
[*] uclibc maybe a good option but I'd rather stick with the normal glibc
[*] minimum console 'ncurses' support, X is optional
[*] was thinking also 'BuildRoot', 'OE' 'yocto/poky' but seems out of my league already

[*] tinycore/microcore is also good as this is what is currently inside the CF card but I'll be migrating to Gentoo for this time

The Guidance/Advise that I need are:
[-1-] So, I need advise on the partition scheme for the 512Mb + 8Gb combo media that I have.
[-2-] building/compiling with these devices will take 'ages' to complete the whole installation thing, what I have in mind is to setup distcc and/or crosscompile on another machine to help speed the process but am a TOTAL noob on distcc/crosscompile. What would you advise on this?
[-3-] since the destination medium are CF and usb flash drive, how to prevent wear and tear? tmpfs?

The finished product will serve as a mini Music Jukebox and as an SMS Centric stuff, facilitating like:
[*] SMS forwarding
[*] SMS to IM and vise versa
[*] any other SMS service I can think of

hoping for the guidance/advice/directions on this subject matter, thanks in advance!

eccerr0r · Posted: Tue Mar 17, 2015 4:45 pm Post subject:

The 512MB storage may be a problem. Likely the best way to start this is to bootstrap with another system, perhaps with a VM and transfer to this machine.

I have an AMD SC520 with a 2GB CF card (and also a Geode GX1 on an ATX dev board, but I think the SC520 is more of a problem). I bootstrapped on a 1GB "486" -- a virtual machine on my Core2 Quad machine. Then I copied the image to the CF card, and started it that way. However since I did use a stage3, this install is a full Gentoo install with the full portage toolchain and because that, it'll be hard to get even a text only system below 450MB due to all the stuff Python and Perl drag along...which will make it hard to get it to fit on a 512MB card and still have space to do anything else. Part of the problem is the huge installed package database, and this isn't even including the /usr/portage/ tree - I have it mounted via NFS - nor temp space for compiling. NFS has to provide that space too.

Was the intent to make this machine self-hosting Gentoo or will you be updating this box by pulling the 'disk' and upgrading via a bigger box?

The intent of my 2GB CF install was the latter, as the SC520 only has 64MB RAM on it... but the install would be done via a VM versus a non-self-hosting stage1 install where python is omitted.

ambad4u · Posted: Tue Mar 17, 2015 4:59 pm Post subject:

eccerr0r · Posted: Tue Mar 17, 2015 7:44 pm Post subject:

Since the portage tree itself (/usr/portage) will exceed 500MB or so, likely you will need to use the 8G flash to be completely self hosting and not depend on NFS.

On a side note, I have a USB 16GB Flash memory that will boot my machines and run completely from it as rootfs is on that media. It's self hosting (I can emerge anything on it, as if it were a regular machine - a bit different from a livecd or liveusb). Its install size was 9GB or so, and has a full portage tree, X11/XFCE desktop, Firefox, 1GB swap, etc. I'm not sure how long this thing will last but it has been working OK, though it is a bit slow due to write speeds.

It's a Lexar branded USB stick if it matters, maybe it'll last a while, who knows. Theoretically there should be wear leveling on USB just like on SATA SSDs.

NeddySeagoon · Posted: Tue Mar 17, 2015 10:34 pm Post subject:

dab_s_bad,

You can put the portage tree into squashfs to keep the size down. You can also --exclude branches from emerge sync.
There is no need to have the whole tree. You do need the space to make the squashfs image somewhere from time to time.

8G is very tight. I have an Acer One netbook from 2009 with the 8G SSD.
It has space for a Gnome2 install but that is achieved by building elsewhere and leaving behind /usr/portage and /usr/src
That comes to about 6G. The toolchain is still there but no portage tree or distfiles.

cross distcc just works but with such a shortage of resources. I would build on more capable hardware, then move it across.
That can be in a chroot or in a VM.

USB sticks are slow you really don't want to build there if you can help it.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

ambad4u · Posted: Wed Mar 18, 2015 12:30 pm Post subject:

Thanks for the inputs @NeddySeagoon and @eccerr0r

I really need to re-think the HDD portion of my system and may resort to use my 2.5" ide HDD for this.
will do this on the weekend.

the problem I have now is the install part and the update part to make it i586 (to satisfy my OCD inside

)

which is better to use for the installation (to speed up)? chroot version or doing it in VM?, does doing chroot does not affect CHOST and CFLAGS?

eccerr0r · Posted: Fri Mar 20, 2015 11:32 pm Post subject:

The nice thing about VM is that you can tailor the environment to match (or at least closer match) the target.
The bad thing about VM is that it can be slightly slower computationally.

The nice thing about chroot is that it runs mostly at native speed (though I find chroot disk access slightly slower, but not slower than the VM).
The bad thing is that if there are any buildtime processor detection, the packages may be built for the wrong CPU.

The third method is using ROOT= and that's really, really buggy, but it's pretty much the only way to do a stage 1 bootstrap. Buggy in that it sometimes gets confused between the ROOT= and the main system (wrt use flags, and also suffers from buildtime processor detection), but when it does works, this is theoretically the fastest build as no emulation is going on, and does not need bind mounts to /proc, etc., to work.
_________________
Intel Core i7 2700K/Radeon R7 250/24GB DDR3/256GB SSD
What am I supposed watching?

ambad4u · Posted: Sat Mar 21, 2015 9:30 am Post subject:

fengalin · n00b Joined: 09 Feb 2008 Posts: 17

Hi dab_s_bad

I use a similar architecture (Linutop 2, see: https://en.wikipedia.org/wiki/Linutop). I use it as a download server mostly (transmission & amule daemons and the matching remote GUI on my main system). I decided to attach a USB HDD for /home and /var/ filesystems. /boot and / are located on the SDCard. See the filesystems on the AMD Geode below:

Ant P. · Watchman Joined: 18 Apr 2009 Posts: 6920

-march=i586 is okay. -march=i486 is safer.

-march=native would be the safest and fastest though; run this on the Geode if you're using distcc to get an equivalent list that'll work:

NeddySeagoon · Posted: Mon Mar 23, 2015 9:21 pm Post subject:

Ant P.

CHOST will 'only' trash the toolchain. If that is never rebuilt and used, it won't be detected.
That its =i686 suggestn that the wrong stage3 tarball is in use, as thats where its set by default.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

fengalin · n00b Joined: 09 Feb 2008 Posts: 17

Thanks both of you for your clarifications. You're right Ant P., I should update the CHOST on the target system. Like I said, I never use the AMD Geode for generation, so it never caused any issue.

Here is the output of the command you suggested:

NeddySeagoon · Posted: Mon Mar 23, 2015 9:57 pm Post subject:

fengalin,

-march=geode should be enough.

You can add -Os or -O2 and -pipe if you want.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

ambad4u · Posted: Tue Mar 24, 2015 1:19 am Post subject:

thanks for the inputs

ambad4u · Posted: Tue Mar 24, 2015 7:38 pm Post subject:

BTW, for learning and curiosity sake..., lets say I have installed gentoo faithfully using the x32 handbook/guide and using a stage3 486 tarball.

how do I convert the ENTIRE thing to i586?

I know that doing this 'natively' will take months to complete

I have also read many things about this particular Proc is that its better to have it stay to i486 than to i586
In the future if I'm able to install it successfully with the i486 variant, would definitely be back asking guidance on to cross compile it if time permits.

thanks to all!

NeddySeagoon · Posted: Tue Mar 24, 2015 7:59 pm Post subject:

dab_s_bad,

Natively, you follow the CHOST changing guide to get a i586 toolchain.
This is really a waste of time, since the CHOST tells what host the toolchain will run on and not the host it will build code for.
That is a CHOST=i486 toolchain will produce code for whatever you put in -march= as losg as its Intel/AMD 32 bit.

You fix your -march= and either let nature take its course with updates or run

fengalin · n00b Joined: 09 Feb 2008 Posts: 17

dab_s_bad,

I forgot to mention: this architecture doesn't use PAE, so make sure to uncheck this in kernel configuration:

ambad4u · Posted: Sat Mar 28, 2015 10:46 am Post subject:

Simba7 · Posted: Mon Mar 30, 2015 5:41 am Post subject:

One thing you could look for is a Microdrive. Basically, it's a 5-8GB Hard Disk in the form of a CF card. You can find them cheaply on eBay. I've used them, and you can put swap on them without fear of destroying your card.

..then.. if you want to.. use parts of the script in my Stage1 build tutorial. That way you can use some features in the processor instead of being stuck with i486. I would highly suggest a decent-sized swap, along with an NFS share for portage.

ambad4u · Posted: Tue Mar 31, 2015 9:12 am Post subject:

ambad4u · Posted: Sat May 02, 2015 7:50 am Post subject:

giving some little follow-ups...

I have somewhat made now my geode system be an i586 one and at the same time a hardened one in one go!?

.
what I did was somewhat like this: [taken from 'change chost' and 'hardened guide']
changed first chost in make.conf

NeddySeagoon · Posted: Sat May 02, 2015 8:27 am Post subject:

dab_s_bad,

If your system is not now i586 we are all in trouble. The CHOST changing guide worked for a lot of users when glibc dropped I386 support.
All that really matters is your -march=

You will need to rebuild the initrd every time you update the kernel if it contains kernel modules.
Its actually slightly worse than that as the kernel and its modules must be built with the same version of gcc.

If your initrd only contains userspace tools, it should work with gentoo-hardened too, no rebuild required.
The initrd won't be hardened but does that matter to you?
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

ambad4u · Posted: Sat May 02, 2015 9:55 am Post subject:

I'm somewhat amazed that I have rebooted a couple of times and I'm still able to use my old geode

anyways, its not much of use as of now that kernel and initrd is vanilla but I would like it to be hardened also as I'll be using this little thing as a mini server (front facing the internet), I'll be using dynamic dns for this for a mini website perhaps or some ssh capabilities also.

and..., when I tried gcc-config (-l/-c) it points to i586 stuff and I guess its good I think as it did not produce any errors and subsequent builds after gcc glibc binutils all went well...

what would you think!?

NeddySeagoon · Posted: Sat May 02, 2015 12:08 pm Post subject:

dab_s_bad,

Its very difficult to use the initrd as an attack vector. Its not running during normal operation but it might still be in the free memory pool.

If your initrd includes networking, you might be more concerned.
The only good reason for that is console over the network.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.

ambad4u · Posted: Sat May 02, 2015 1:18 pm Post subject:

NeddySeagoon,

I have initrd because I have lvm and because I want a filesystem that is I can shrink/enlarge later.

I have read somewhere here also that we can use resize2fs or something. can I use resize2fs on ext4 without lvm to shrink/enlarge an ext4 filesystem?

honestly, I'm a super noob on this, I do not even know the whole purpose of the initrd

but am still learning