Powerd and est / eist functionality

Jeremy Chadwick freebsd at jdc.parodius.com
Sun Mar 28 21:14:01 UTC 2010

On Sun, Mar 28, 2010 at 12:42:02PM -0700, Jeremy Chadwick wrote:
> I'll see if I can find a very high resolution photo of your motherboard
> and try to work out if any ASICs are used for H/W monitoring (these days
> such chips also often provide Super I/O support (floppy, LPT, COM,
> LPC/ISA, etc.)).  I'll probably have to review the user manual.
> I'll report back once I do that.

Success -- the Gigabyte GA-G41M-ES2L board uses an ITE IT8718 Super I/O
chip, which also drives H/W monitoring support.  Verified both visually
and in the user manual.  The official datasheets for the IT8718 are here:


Regardless of chip subrevision (J vs. K), neither supports SMBus; the
chips appear to be entirely LPC/ISA-based.

mbmon could be extended/enhanced to support this chip (mbmon -I would be
required), but you'd still need to know what I/O ports are that Gigabyte
tie to the chip.  That's where Linux lm-sensors comes into play.  Based
on some Google results, the base I/O port is probably 0x290 (I'm
assuming 0x290 = read, 0x291 = write) -- but I'm basing that on some
ambiguous output here:


There's also this, which is pretty disheartening:


"The IT8718F also features VID inputs (up to 8 pins) but the value is
stored in the Super-I/O configuration space. Due to technical
limitations, this value can currently only be read once at
initialization time, so the driver won't notice and report changes in
the VID value. The two upper VID bits share their pins with voltage
inputs (in5 and in6) so you can't have both on a given board."

If someone feels like contacting the mbmon author to get this added, be
my guest.  Or if someone feels like adding it to mbmon, that's cool too.

| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |

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