Re: HME and IPX

All,

On 4 August 2011 18:57, Jochen Kunz <[email protected]> wrote:
> On Thu, 4 Aug 2011 09:26:20 +0800
> Simon Fryer <[email protected]> wrote:
>
>> While we are discussing IPX's. I quick review of the BSD's (Open/Net)
>> indicate that there is no support for the HME 100MB sbus ethernet
>> interface on the 4c platform.
> How do you come to this conclusion?
> hme(4) is in the default (GENERIC) kernel configuration:
> $ grep -B 1 ^hme /usr/src/current/src/sys/arch/arch/sparc/conf/GENERIC
> ## Happy Meal Ethernet
> hme*    at sbus? slot ? offset ?

1) The error messages while the kernel probed and initalised the
hardware was the first hint.

2) in /usr/src/sys/arch/sparc/conf/GENERIC on OpenBSD 4.9
# HappyMeal ethernet (will not work on sun4c)
hme*    at sbus?

I am running the distribution kernel and given the age of the platform
I wasn't really expecting any additional hardware support.

>> Is there a technical reason why the HME
>> interfaces are not supported on the sun4c platform, or is it purely a
>> BSD driver issue?
> There may be a hardware or firmware incompatibility, that makes it
> impossible to use a HME in a sun4c. I dim remember that some cg6 / TGX
> cards have this problem with some early sun4c machines. Besides this,
> nothing prevents you from adding hme(4) to the kernel and use it. The
> hme(4) driver interfaces to the platform independent sbus(4) bus_space(9).
> It should not noitce at all if it runs on port-sparc or port-sparc64.

Okay. This looks good and answers my questions about if I should spend
some time trying to get it to work, or there is a fundamental
architecture issue that I will come across after several nights of
background reading. So, it seems that it is purely a driver issue.

Simon

--
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"Well, an engineer is not concerned with the truth; that is left to
philosophers and theologians: the prime concern of an engineer is
the utility of the final product."
Lectures on the Electrical Properties of Materials, L.Solymar, D.Walsh