Experimental Physics and
Industrial Control System

Eric Norum <[email protected]> · Fri, 2 May 2008 10:31:57 -0500

On May 2, 2008, at 10:22 AM, Till Straumann wrote:

It just seems that rtems_netconfig.c mixes functionality of

initializing RTEMS

(networking, console, ...) and initializing EPICS (some generic

things, some

os/RTEMS specific).

How so?

As far as I can tell, rtems_netconfig.c contains nothing but the

network configuration structures.

At least that's all that I intended it to contain.

IMO it would be useful to break the two apart so that users

implementing

their own RTEMS initialization can still use the pieces that deal

with initializing

EPICS (w/o having to copy/paste from rtems_netconfig.c)

For network configuration, the hooks mentioned in the release notes

should be all that's needed to implement custom tweaks (no copying of

rtems_netconfig.c required). For example, our BPM embedded IOCs set

all their network configuration based on the setting of front-panel

switches.

There are no corresponding hooks for RTEMS configuration at the

moment, though.

- Till

- Andrew

Eric Norum wrote:

There are some mechanisms already available.

1) EPICS RTEMS support breaks the configuration/initialization

into several source files. If, for example, your application

requires some specialized network configuration, simply copy

rtems_netconfig.c to the application directory, make the changes,

and add rtems_netconfig.c to the application Makefile. To do this

on a site-wide basis, put your site-specific version of

rtems_netconfig.o into a support module where it will be linked

before -lrtemsCom is encountered. There's a separate

rtems_config.c file, too.

2) As noted in the EPICS R3.14.10 release notes, there are some

hooks to make it easier to set up your own specific configuration:

Added hooks for application routines to supply special network

configuration parameters. The RTEMS startup code calls

epicsRtemsInitPreSetBootConfigFromNVRAM just before reading

values from NVRAM and epicsRtemsInitPostSetBootConfigFromNVRAM

just afterwards. See epicsRtemsInitHooks.h for prototypes and

global variables.

On May 1, 2008, at 4:10 PM, Andrew Johnson wrote:

Till Straumann wrote:

seems that 3.14.10 does a more initialization in the 'Init'

function

which we don't use (e.g., because it hardcodes things like the

the

amount of mbuf  (networking buffers) space [which ends up
being the same] and whether BOOTP should be used.

IMHO we should come up with a better way of initializing the

system

that is more flexible (here we use a bootloader plus a small

library

for connecting the bootloader, user interactive input, non-

volatile memory

and the bootee).

For the time being, IMHO 'Init' should be broken up into pieces
that
a) deal with initializing RTEMS (networking, filesystem, console)

b) deal with initializing EPICS (setting some environment

variables,

  rtemsTicksPerSecond_double etc.)

The user should be able to override all of (a) but use (b) to

initialize

EPICS on an RTEMS system of her preference.

That seems entirely reasonable, can you work with Eric to come up

with a proposal and patch that works for both camps? R3.14.10 is

not set in stone yet, and it would be good to get this cleared up

before the release.

- Andrew

--
Eric Norum <[email protected]>
Advanced Photon Source
Argonne National Laboratory
(630) 252-4793

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System