From: rtcoffin@austin.ibm.com (Coffin)
Subject: Item #397: DSE: 'auto' string in network device properties
Date: Thu, 12 Dec 96 11:48:43 -0600


P1275 Openboot Working Group Proposal -- Proposal #:397 Ver 1.0

Title:          Include 'auto' string in Network Device Properties

Author:         R. T. Coffin

Date:           12/12/96

Ed/Tech:        Technical

Synopsis:       Add 'auto' string defintion to Network Device Properties

Doc & Version:  Device Support Extensions, Recommended Practice, Version 1.0

Problem:        Need a means for the "chosen-device-type" property to indicate
                to network device FCode to perform 'auto-negotiation' during
                a configuration or an initialization operation.

Proposal:

There is a need to incorporate an additional string value of 'auto' for the
parameters 'speed=n' and 'duplex=mode' in Section 9.1 ("network" device
properties) for the properties "supported-network-type" and "chosen-network
-type" [the second (speed) and forth (duplex) fields].

These two parameters would be used as shown below:

        speed=4,10,...,1000 or 'auto'

                and/or

        duplex='half', 'full' or 'auto'

where 'auto' indicates the device driver is to perform an 'auto-negotiate'
function for the speed and/or duplex functions if the network device is
capable of auto-negotiating.

The fields for 'speed' and 'duplex' could have a string value of 'auto'.

  Examples of a string value using 'auto' follow for 'network' device
  properties:

        "ethernet,10,rj45,auto"      -  auto-negotiate is supported for duplex
                                        mode
        "ethernet,auto,bnc,auto"     -  auto-negotiate is supported for speed
                                        and duplex mode
        "token-ring,auto,9pin,auto"  -  auto-negotiate is supported for speed
                                        and duplex mode

The value of the "chosen-network-type" property with an 'auto' string
included would indicate that the network device is to be configured by
auto-negotiation (input to the FCode), where the value of the "chosen-
network-type" property could have been established by an OS NVRAMRC
Script.  If the 'network' device has been initialized and/or configured with
the 'auto' string present, then 'network' device FCode would leave this value
for the "chosen-network-type" property value in the speed and/or duplex fields
after the network device was configured and/or initialized.  Leaving the 'auto'
string value in the property value would allow Open Firmware to reinitialize
a network device to auto-negotiate for multiple instances for each boot
operation.

This feedback path would allow an OS to control how a 'network' device could
be configured for each boot through a NVRAMRC Script from the
"chosen-network-device" property value;i.e., using the property value as input
to the 'network' device FCode.




-- 
 Regards,                 ______________________________________
                          \ R. T. Coffin, IBM - Austin, TX.     \
     /_)   /')  /_)        \ RS/6000 Hardware Architecture       \
    /__)  /_/  /__)         \ (512) 838-8240  Fax: (512) 838-6783 \
                             \  e-mail: rtcoffin@austin.ibm.com    \
================== N4LXK -30- ======================================\



[ P1275 Item #397 -- Received: Thu Dec 12 09:48:20 PST 1996 ]