# Via EPIA M10000 Nehemiah make.conf and kernel setting info

## htpc101

I just got a Nehemiah Chipset Via EPIA board and am unsure of make.conf and kernel settings.  A good friend running debian on his Nehemiah reports quote "the Nehimahah chip uses a VIA-C32 chip rather than the VIA C3 chip and support for that chip is only avaiable in the later 2.4.21 kernels".  Anybody out there have info??  Thanxx

Mike

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## lazarusrat

I haven't heard anything about this. I've also not heard of a "C32." Nehemiah is, I believe, the third core to be offered in the C3 chips (first was Samuel 2 then Ezra-T). It's still a C3, though.

I know that with kernel 2.4.19 and 2.4.20 (and probably earlier), the C3 option compiles the kernel for an i486. So, given that the C3 didn't suddenly become an Alpha or something, you should be fine with kernels earlier than 2.4.21.

The built-in random number generator isn't supported until the later 2.5 kernels, but it's not something that's going to keep your box from working. It's possible later 2.4 kernels have some other support that gives better performance on a Nehemiah, but again, I haven't heard anything to that effect.

For make.conf, you can use march=i586. There are rumors that the Nehemiah C3s actually contain the cmov instruction, which is the only thing keeping Ezra-T C3s from being okay as march=i686. I haven't seen any confirmation of that though. Check /proc/cpuinfo to see what other flags it supports.

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## htpc101

Well, I put together a plywood system with the Nehemiah mobo and have an update.  I decided to shoot high on GCC optimizations and work my way down.  I am pleased to report that stage 1 (1.4_rc4) sucessfully bootstrapped and emerged with 

```
-march=pentium2 03 -fomit-frame-pointer -pipe
```

  It makes me wonder if I could get away with Pentium3.  In any event, stage 2 is now underway with the same optimizations.  I will continue to report what I find in this project.  I should mention that the only Gentoo boot disk with a kernel setup that could find the Via-rhine driver without modprobe and IRQ hassle was a 1.4_rc2 disk I had laying around.

Mike

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## lazarusrat

You might want to check your /proc/cpuinfo for other flags you can set.

The Nehemiah, according to Via, supports SSE. The Ezra-T C3 supports 3dnow and mmx, and I doubt those will have gone away. So you can likely add -m3dnow -mmmx and/or -msse if you want. I don't know which/how many of those are activated by the various march= options.

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## atom

 *htpc101 wrote:*   

> I just got a Nehemiah Chipset Via EPIA board

 

curious, but where did you get the board with the nehemiah chip?

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## htpc101

Well, after many experiments, I can report more about this board:

1.  The march=Pentium3 flag in make.conf crashed on gcc (although ncurses and binutils made it).  For me the flags in my above post worked well.

2.  Using the data in thishttps://forums.gentoo.org/viewtopic.php?t=47796&highlight=epia,thread, I got the CVS xfree86 via driver running.  Don't be temped to xmkmf the Imakefile with the CVS, I wasted a lot of time on that.

3.  I did indeed have to use a 2.4.20 patched to 2.4.21-rc1 kernel from kernel.org to get the option VIA-3-2 Processor under "Processor Type and Features" in the make menuconfig (not VIA 32 as reported from my Debian buddy).  cat /proc/cpuinfo reports the following flags

```
fpu de tsc msr mtrr pge cmov mmx fxsr sse
```

4.  The kernel was compiled with agpgart as a module that would not insmod without the agpgart suffix AGP_TRY_UNSUPPORTED=1 in /etc/modules.conf.  When I do a lsmod, however, agpgart comes back as (unused)

5.  The alsa-driver was emerged with 

```
ALSA_CARDS='via82xx'
```

 in my make conf.  After I emerged xmms, alsa-xmms, and xmms-mad, the driver works intermittently and produces horrible sounds accordeing to the datarate of a given shoutcast broadcast, with 48Khz working fine and others not (?).  This may be a broken xmms build, I have run into that before, so I will wait a week or so, emerge sync, and try again.  (The current xmms-version with

```
ACCEPT_KEYWORDS="~arch"
```

is 1.2.7-r20.

6.  I bought my Nehemiah on eBay, but they are also available on iDot.com.  I think that answers lazarusrat's and atom's questions.

My challenge is to now get a media player working.  I have emerged Xine, mplayer, and vlc.  Since I have no dri with the via driver, and no glx, my options seem to be limited.  I uncommented the line in XF86Config to allow dga to work, and it does so with mplayer, but much to be desired in performance.  Any suggestions??

This post has been edited for a significant error on the point #4 above, and the points have been renumbered since I occasionally cannot count.

Mike

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

"When man does not believe in God, it is not that he believes in nothing; he believes in anything, no matter how ludicrous or lethal" - G.K. Chesterton 

That's why I believe in Linux!!Last edited by htpc101 on Fri May 02, 2003 5:04 am; edited 1 time in total

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## lazarusrat

For the sound, I've got alsa 0.9.0-rc6. The crackling and stuff happened after that version, I haven't tried the 48K trick. I run esd to be able to hear more than one thing at once (moz/xmms).

I haven't had any problems with mplayer. If you put xv in your USE flags, you can use mplayer -vo xv for decent output. I'm not playing anything massive with it, though.

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## htpc101

Thanks lazarusrat for the sound tip.  It worked perfectly!!

I am still in the midst of video problems.  When I start mplayer with the option -vo xv, the Xserver crashes back to the console.  My assumption is that this part of /var/log/XFree86.0.log is quite relevant: 

```

(--) via(0): mapping framebuffer @ 0xd8000000 with size 0x2000000

(WW) via(0): Failed to set up write-combining range (0xd8000000,0x2000000)

(--) via(0): Frame buffer start: 0x40274000, free start: 0x500000 end: 0x2000000

(--) via(0): mapping MMIO @ 0xdc000000 with size 0x9000

(--) via(0): mapping BitBlt MMIO @ 0xdc200000 with size 0x10000

(II) via(0): vgaHWGetIOBase: hwp->IOBase is 0x03d0, hwp->PIOOffset is 0x0000
```

Further, cat /proc/mtrr reveals

```
reg00: base=0x00000000 (   0MB), size= 512MB: write-back, count=1

reg01: base=0x1e000000 ( 480MB), size=  32MB: uncachable, count=1

reg02: base=0xd0000000 (3328MB), size= 128MB: write-combining, count=1

reg03: base=0xd8000000 (3456MB), size=   8MB: write-combining, count=1
```

If I do

```
echo "base=0xd8000000 size=0x2000000 type=write-combining" >| /proc/mtrr
```

then cat /proc/mtrr is unchanged

Going back further, cat /proc/pci reveals:

```
    VGA compatible controller: PCI device 1106:3122 (VIA Technologies, Inc.) (rev 3).

      IRQ 11.

      Master Capable.  Latency=32.  Min Gnt=2.

      Prefetchable 32 bit memory at 0xd8000000 [0xdbffffff].

      Non-prefetchable 32 bit memory at 0xdc000000 [0xdcffffff]
```

I have agpgart compiled as a module with all chipsets enabled.  The module will only insmod with the "agp_try_unsupported=1" argument and lsmod  reports that agpgart is (unused).  

As reported above, cat /proc/cpuinfo reports that the Via C3-2 supports mtrr.  Any help would be appreciated.  The whole purpose of this little board was to get a little multimedia machine running.  Thanks!!

Mike

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

"When man does not believe in God, it is not that he believes in nothing; he believes in anything, no matter how ludicrous or lethal" - G.K. Chesterton 

That's why I believe in Linux!!

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## Gnufsh

I'm looking at getting one of these. Could you post you /proc/cpuinfo please?

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## htpc101

Sure, here it is:

```
bash-2.05b# cat /proc/cpuinfo

processor       : 0

vendor_id       : CentaurHauls

cpu family      : 6

model           : 9

model name      : VIA Nehemiah

stepping        : 1

cpu MHz         : 999.550

cache size      : 64 KB

fdiv_bug        : no

hlt_bug         : no

f00f_bug        : no

coma_bug        : no

fpu             : yes

fpu_exception   : yes

cpuid level     : 1

wp              : yes

flags           : fpu de tsc msr mtrr pge cmov mmx fxsr sse

bogomips        : 1992.2
```

Mike

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## Borgasm

Has anybody set up their M10000 Nehemiah as a set top box?

http://freevo.sourceforge.net

I have heard that the ITX boards can barely play DVD's, but I am wondering about their performance on DivX movies, etc...

I believe the older VIA CPU's floating point ran at half clock, and would seriously degrade performace, but the Nehemiah runs at full tilt.

I am making a car multimedia computer, and then moving it to be my PVR in an apartment. Just making sure I have enough power to decode movies and such.

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## htpc101

One of the guys at our LUG has just such a box.  He eschews freevo, uses myth tv on a debian distro Nehemiah with a 40gig HD.  He is not using X, bit has it all running in framebuffer.  I saw it and it looked good on replays, with a Hauppage PVR-250 (I believe) card, which was chosen for its MPEG encode capability.  He says the processor is pretty much out of instruction space on MPEG decode since there is still no linux driver for the MPEG decode support built into the Nehemiah mobo.

Mike

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

"When man does not believe in God, it is not that he believes in nothing; he believes in anything, no matter how ludicrous or lethal" - G.K. Chesterton 

That's why I believe in Linux!

----------

## Borgasm

Interesting, because I am running a Duron 1GHz on this box.  My /proc/cpuinfo looks strangely like the M10000 Nehemiah (above).

It runs DivX, DVD, TV...etc...just fine....

Perhaps its the special instructions/flags on the Duron that gives it an edge....but I tend to doubt it.

But he is right...freevo is quite possibly the most bloated program since OpenOffice....

 *htpc101 wrote:*   

> One of the guys at our LUG has just such a box.  He eschews freevo, uses myth tv on a debian distro Nehemiah with a 40gig HD.  He is not using X, bit has it all running in framebuffer.  I saw it and it looked good on replays, with a Hauppage PVR-250 (I believe) card, which was chosen for its MPEG encode capability.  He says the processor is pretty much out of instruction space on MPEG decode since there is still no linux driver for the MPEG decode support built into the Nehemiah mobo.

 

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## BradB

I don't think that the Mhz stacks up between the EPIA & Duron/athlon class CPUs.  I've heard that a C3 processor roughly equals 1/2 the Mhz of a P3 CPU.

Brad

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## htpc101

A few observations:

On the emerge system with whatever kernel boots the Gentoo 1.4_rc2 PIII disk, with a bootstrapped stage 1 1.4_rc4, the compile time for the xfree 4.3.0-r2 after download and patching was 2 hours and 15 minutes.

On the same system, after a 2.4.21-rc2 vanilla kernel was compiled with the Via C3-2 option under processor type and features, the compile time for the entire 10 May xfree cvs tree was 1 hour and 50 minutes.

On a Gentoo 1.4_rc4 based PIII 1 gig system with gentoo sourced 2.4.20 kernel (no need for 2.4.21 for the C3-2 option) the compile time for the same entire xfree cvs tree was 1 hour 45 minutes.

I realize that there are apples and oranges in the above observations, but the salient point is that the Via C3-2 option available in 2.4.21 pre and rc kernels make the Nehemiah core significantly faster.

Mike

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

"When man does not believe in God, it is not that he believes in nothing; he believes in anything, no matter how ludicrous or lethal" - G.K. Chesterton 

That's why I believe in Linux!!

----------

## Borgasm

And just when I thought hope was lost, a review comes along....

http://slashdot.org/article.pl?sid=03/05/19/1642255&mode=nested&tid=137

Interesting stuff...clears things up a bit....

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## Borgasm

Does anybody have data on the power consumption of the M10000 board installed in a full system.

I am looking into making a set top box with a 55W DC power supply. I'm not sure if this will be enough to run a DVD player, hard drive, and the M10000 board.

They say the CPU only draws ~11W, but other chips on the board draw power too, same with the HD and DVD.....

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## lazarusrat

You're likely to find better power consumption info at http://linitx.org or http://forums.viaarena.com. People have been reporting problems with Epia boards on 55W PSUs there for basically as long as the combination's been available. You'll have a lot better luck with a laptop DVD & hard drive, but even that can sometimes have problems, apparently. With some of the PSUs, it seems to have something to do with grounding (or lack thereof), and/or inadequate power from the 5V on certain PSUs.

According to http://forums.viaarena.com/messageview.cfm?catid=32&threadid=38365, http://www.dc2dc.com/ has 100W DC PSUs available if you contact them, even though their online store still says "coming soon." That post is probably worth keeping an eye on, since the poster doesn't have his PSU yet (or even a price as of right now).

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## richone

I found a system-wide fix to the sound problems and posted a mini-how-to for sound on the via eden boards.

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## zoltar

Just a data point: I just installed an entire stage 1 Gentoo system using CFLAGS="-march=i686 -mmmx -msse" and everything is cool...

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## taskara

this is a great thread, please keep posting anything you find!!

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## lazarusrat

About the i586/i686 thing:

The Ezra-T C3s were missing the "cmov" instruction in their instruction set. This was the only thing keeping them from handling i686-compiled code. Gcc considers that part of the i686 instruction set, even though it's optional, with no way to turn it off.

The /proc/cpuinfo (higher up in this thread) of Nehemiah C3s shows "cmov" in its list of features, so they've added that apparently. Since that was the only thing missing from Ezra-T, poof, all of the sudden the Nehemiahs are i686.  :Smile: 

Note sse replaced 3dnow, too.

There shouldn't be too many more Ezra-T boards floating around for much longer, but it's something to be wary of.

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## cisox

Hello everyone. I just got the EPIA M10000 with the Nehemiah processor. It is a beautiful thing. Support is linux is a bit of pain but it is still worth it. For some great resources on how to get this board to work, check out http://forums.viaarena.com. This place is crawling with all the help you would ever want to find for the EPIA boards. They have a great howto regarding how to get pretty much everything working on these boards. Also they even have a Gentoo howto on there somewhere. Well, I hope that helps anyone who is further interested in this board.

Long Live Linux!

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## taskara

perhaps here and here

 :Smile: 

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## icwhiting

I just thought that I would make a post about the performance issues surrounding the VIA C3 processor.

1. Before VIA released their 1GHz processor there was performance issues, these were largely due to the speed of the FPU. With the release of the 1GHz processor the speed has been vastly better.

2. The C3 processor was never designed for cutting edge number crunching performance, it was designed for low power, low temperature performance. With low temperature comes the posibility of smaller fans and less noise. Ideal for silent PC's or set-top boxes.

3. It is very cost effective when purchased as a complete motherboard / processor package such as the EPIA CL-10000 with a 1GHz C3 processor.

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