Gentoo/MIPS LiveCD [VERY EXPERIMENTAL!!]

Kumba

If the topic hasn't provided any indication yet, this is a topic for discussion of the LiveCD design the Mips Team has debated, pondered, and worked on. This is a very experimental design, and differs from the traditional concept of bootable CDs greatly, primarily due to the inability of SGI PROMs to read ISO9660 format.

Essentially, the CD is partitioned like a disk, complete with an SGI Disklabel, a Volume Header (and Volume) partitions, and a data partition containing the root filesystem. This approach was taken because it should work universally across all SGI systems (in theory), provided a arcboot binary and kernel designed for that system is available.

Several things to note regarding this method of design:

The kernel is patched to allow detection of the partitions on the CDROM. This patch is experimental, was briefly discussed on LKML in Feb 2004, and will trigger a couple 'Call Traces' in dmesg, which so far, appear to be relatively harmless.

It would be much appreciated if anyone out there familiar with the block device subsystem of the kernel would be willing to take a look at this patch, and see if it can't be whipped up into something more functional. Posted below are some links of interests:
http://lwn.net/Articles/72929/ (Article)
http://lwn.net/Articles/72676/ (Original Patch)
http://seclists.org/lists/linux-kernel/2004/Feb/5753.html (LKML Discussion from Feb 2004)
Arcboot is rather slow at loading kernels off the disc. I have been told that there's not much of a way around this for some reason (that I can't recall atm), but with this current test, expect Indy kernels to take upwards of ~10 minutes to boot and load. I hope to resolve this to some degree by modularizing the kernels and shrinking them down (they're monolithic for now).
The userland on the CD is basically the 20040802 netboot userland, just copied into the data partition of the CD. Eventually, I'll figure out catalyst enough to build a real Gentoo LiveCD root, and use that for testing, but this suffices for now as it is merely to test the actual design (skeleton, if you will) of the CD.
This CD only boots Indy/Indigo2 and O2 systems (r4k, r5k, rm5k2) right now, as that's pretty much the only ones Arcboot can boot for now (O2 RM7K is untested). Further support for other systems *might* be possible, but this is highly dependent on whether we can coax a 64-bit arcboot out, and that's not exactly an easy thing to do.

Further information can be found in the file titled "README". I encourage everyone to read that first, then ask questions. MD5 and SHA1 sums have also been provided.

Oh, and before I forget, you can find the test image (mips-livecd-prototype-rc1-20041025.img) on the mirrors in experimental/mips/livecd. Use this topic for any discussion regarding this CD, and for questions, comments, flames, ideas, patches, etc...

--Kumba
_________________
"The past tempts us, the present confuses us, the future frightens us. And our lives slip away, moment by moment, lost in that vast, terrible in-between."
--Emperor Turhan, Centauri Republic

mattpayne · n00b Joined: 22 Jan 2004 Posts: 23

is there an image available that can be burnt from a windows PC??? (currently only machine with CDRW

)

also, how do you put the environment back to default on the O2...

when i start it up it now doesnt boot, as its looking to boot from the CD...

Kumba · Posted: Wed Oct 27, 2004 11:19 pm Post subject:

If you're using a Windows system to burn, then the best I can suggest is a program that doesn't try to force anything. It should just let you select the file and burn it. The file itself is not an ISO image, but burninjg it as if it was an ISO *might* work. I'm not for certain on this, however, as I haven't done burning from Windows for quite a long while.

As for resetting the O2 to defaults, just get into the PROM Command monitor and you shou7ld be fine. It sounds like to read the README file and set the four variables accordingly, but left your system in autoboot mode. If you can get into the prom (usually by pressing ESC at bootup on the graphical or serial console), then you can issue "setenv AutoLoad No" and that will disable auto booting and always drop you to the Prom monitor on serial, or a graphical prom screen.

--Kumba
_________________
"The past tempts us, the present confuses us, the future frightens us. And our lives slip away, moment by moment, lost in that vast, terrible in-between."
--Emperor Turhan, Centauri Republic

Kumba · Posted: Wed Oct 27, 2004 11:21 pm Post subject:

Also, if you download the CD image, check it's file size and md5sum/sha1sum. There appeared to have been some kind of hiccup during the mirror transfer process that caused only 302MB of 335MB to get uploaded. Make sure that if you downloaded the incomplete copy to re-download the fixed copy.

--Kumba
_________________
"The past tempts us, the present confuses us, the future frightens us. And our lives slip away, moment by moment, lost in that vast, terrible in-between."
--Emperor Turhan, Centauri Republic

mattpayne · n00b Joined: 22 Jan 2004 Posts: 23

Ok, just redownloaded the CD, I was lazy, and didnt check the MD5 and had only downloaded 302mb!

Image burned fine on my windows PC (changed file extention to iso and burned with nero)

My O2 recognises and loads arcboot from the CD but crashes after about 4 mins...

I get a screen that looks like the normal O2 boot screen (with a ghosted box where 'stop for maintainance' ususallly is) but with a frozen mouse pointer and lots of graphical corruption... the only way out is to hold the power button in and reset the machine...

mattpayne · n00b Joined: 22 Jan 2004 Posts: 23

Zeroing memory
Starting 32-bit kernel

are the last 2 commands shown on the screen before the machine fails...

I now cannot get the machine to boot to the hard drive... the setenv commands are saved to the prom so its always trying to boot from the CD...

Booting the system normally (without anything in the CD drive) gives me this command box -
--------------------------------------------------------------------------------

dks0d4s8: Drive not ready:Medium not present
dks0d4s8: drive is not ready

Unable to execute pci(0)scsi(0)disk(4)rdisk(0)parttion(

/ip32 media not loaded

No volume header on device: pci(0)scsi(0)disk(4)rdisk(0)partition(

/ip32

Unable to boot; press any key to continue:

------------------------------------------------------------------------------------

at which point im dropped back at the maintainance menu...
how do i reset the environment variables back to default so it will boot cleanly from the hard drive?? ive tried power of and power cable out over night, but looks as though the setenv saved into the prom...

freshy98 · Posted: Fri Oct 29, 2004 8:58 am Post subject:

mattpayne, if you do "help" in the PROM monitor you will see a option called "resetenv". this resets the PROM environment to default settings.
then do "init" which will save and reset the O2. make sure to check if the settings are ok with "printenv".
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mattpayne · n00b Joined: 22 Jan 2004 Posts: 23

poulpe · n00b Joined: 21 Oct 2004 Posts: 10 Location: France

Hello Kumba

I tried the experimental liveCD but it failed for me too.
I used it via serial console on my O2 R5k 180MHz 256Mb (without screen and keyboard attached), the kernel seems to load fine but crashed at start :

Kumba · Posted: Sat Oct 30, 2004 1:05 am Post subject:

poulpe · n00b Joined: 21 Oct 2004 Posts: 10 Location: France

I tried liveCD RC2 and it seems to works perfectly on both serial console and framebuffer output... Amazing work Kumba !

Since I have some spare scsi disks, I'll try to bootstrap the system from the liveCD.

By the way, my PROM parameters are:

Kumba · Posted: Tue Nov 02, 2004 11:19 pm Post subject:

mattpayne · n00b Joined: 22 Jan 2004 Posts: 23

heres the HINV from my O2 which the CD didnt work quite right...

What command do you put in the shell to get the prom version???

Kumba · Posted: Thu Nov 04, 2004 12:12 am Post subject:

squawker · Posted: Thu Nov 04, 2004 7:49 pm Post subject:

Hey Kumba - great work

This O2....

poulpe · n00b Joined: 21 Oct 2004 Posts: 10 Location: France

For info, I successfully bootstrapped/emerged system from scratch (with LiveCD RC2) and rebooted my O2 r5k with my own custom kernel from hard drive.
No netboot was used during the process !
Once again great work Kumba !

squawker · Posted: Tue Nov 09, 2004 10:13 am Post subject:

Poulpe, Kumba

I'm almost there too. System is boostrapped and emerged. Hit a snag with an undefined IRQ compiling 2.6.9 + mipscvs-2.6.9-20041022, and I'm not sure my .config is totally sane as its my first mips/sgi kernel. Hopefully I'll get it sorted tonight. Yeehaa!

-Andy

squawker · Posted: Wed Nov 10, 2004 9:17 am Post subject:

Okay, I'm new to all this and I've run into a few problems building a kernel for the O2 I mentioned above. Kernel source checked out of CVS last night. I'm compiling native on the bootstrapped/emerged Gentoo system.

squawker · Posted: Wed Nov 10, 2004 11:32 am Post subject:

Following up myself here - I've read the man page for arcboot and I think I'm getting the big picture now.

Very confused about 32 vs. 64 bit though. I thought R5000 was a 32 bit arch, but you only get to build an ip32 kernel if you select CONFIG_MIPS64. Huh?

Also, linking doesn't seem to work unless CONFIG_BUILD_ELF64 is selected. From the Config Help this seems to be a limitation in later binutils - is it correct to select this? Will it work? I noticed that the kernel on the livecd didn't have this selected, so I guess it was built with older binutils. Any tips or explanations will be received with much gratitude.

-Andy

poulpe · n00b Joined: 21 Oct 2004 Posts: 10 Location: France

I agree that building a good working kernel for an O2 is far from easy.

You should use one of the 2.6.x ebuild provided in portage 'mips-sources' instead of using straight CVS method cause Kumba added some 'well-known' patches which are not integrated into CVS. The problem of 'option' vs 'options' in GBE framebuffer is a good example but there are other fixes too => it is most likely that your framebuffer will not work at all if you compile from CVS sources.

R5000 is a 32bit arch but you need to build a 64bit kernel to get arcboot to work (and this way, boot from the hard drive instead of netboot). This allows also to use more than 256Mb of RAM in your O2. There is normally a performance loss with a 64bit kernel but I don't find it significant for now.

You'll find at the URL below the config I used to build my kernel and the output of dmesg after the boot. I used the mips-sources-2.6.9-r2 ebuild to generate the kernel.

http://nova.dyndns.org/config-spoutnik.txt
http://nova.dyndns.org/boot-spoutnik.txt

Hope that helps! :roll:

Kumba · Posted: Sat Nov 20, 2004 10:42 am Post subject:

UltraHarry · n00b Joined: 27 Dec 2003 Posts: 21 Location: Hamburg

hi,
thanks for the live-cd. after some problems, caused by the use of a cd-rw instead of a simple cdr (the installed o2 cdrom seems to be a bit picky), the machine booted. but to my disappointment, it still refuses to work with my installed tft-panel (1600SW). so all i saw was a black screen. is there some workaround for this behaviour yet?
unfortunatly im neither a kernel hacker nor am i able to program C any good. but i nevertheless would like to share my experiences on this topic for anyone giving me a kernel that might work. maybe kumba remembers some talk we had about this. one of his kernels actually gave some weired output to the panel.

or is it true, and i am the only one, using that panel?

regards,
harry
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libellous · n00b Joined: 10 Jan 2005 Posts: 8 Location: LONDON

Silly question and of no practical use to myself - my machines will both boot from the live CD anyway. Would it be possible to bootstrap some of the newer boxes from a cd by using sash off an irix boot install cd to boot a kernel? I might give it a go just for interest's sake anyway.

lhaza · n00b Joined: 26 May 2006 Posts: 1

I had the following experiences with the Live-CD rc5 on my irixboxen:
O2 r10k sash not found
Octane2 r12k sash not found
Fuel r14ka
ARCLoader version 0.43 (c) Stanislaw Skowronek
Loading configuration for 'unix'...
Detecting system parameters

here it hangs for at least 10 minutes. what surprised me that it kinda worked best on the fuel-box.

greetings

Redhatter · Posted: Fri May 26, 2006 4:50 am Post subject: