On Wed, Sep 10, 2008 at 11:19:10PM +0100, Bruce M Simpson
wrote:> Hi there,
>
> I have been looking at a system which has the Intel ICH7 south bridge.
>
> Whenever I try to probe the SMBus on this system with 'smbmsg -p',
I get
> a lot of status=41 timeout messages in dmesg from the ichsmb(4) driver.
>
> I have been given the addresses of the SMBus peripherals and have tried
> initiating reads to their register space directly using 'smbmsg',
with
> the same result.
Yes, I have seen this behaviour but *only* when querying a slave address
which was incorrect or had no device tied to it. You should not be
using the "8-bit data address".
> * Has anyone seen the same issues with the ICH7?
All of my development on bsdhwmon has been done exclusively on ICH7
chipsets, except for the hardware I don't have access to (which use
other chipsets, but still use ichsmb(4)):
http://bsdhwmon.parodius.com/
During early development of bsdhwmon, I used smbmsg exclusively for
testing.
So in that respect, no, I've never seen the problem you report.
> * Does anyone know of any userland code I could use as an alternative to
> the ichsmb(4) driver?
>
> I looked at mbmon, it appears it relies on the smb(4) drivers; its
> direct ISA access only works for specific hardware monitoring chips
> which appear on the ISA/LPC bus and does not implement SMBus bit-banging
> in userland.
mbmon does not use SMBus properly, or in the way you think it would.
It's a bad example.
If you would like some real code that interfaces with ichsmb(4)
reliably, let me know and I'll send you the current tarball to bsdhwmon.
It's very clean/easy to follow code.
If you're working on a hardware monitoring tool, possibly it would just
be best for me to include support for it in bsdhwmon.
--
| 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 |