[Emc-developers] emc 2.4: hostmot2 firmware images

[Jeff E. <je...@un...>]

Thanks to the help of Peter and Seb, I feel pretty confident about the
hostmot2 firmwares I announced last week --
    http://article.gmane.org/gmane.linux.distributions.emc.devel/2834

For emc2.4 I'd like to use these built firmwares in place of the ones
that are presently in our source tree.  Here is how I envision that
happening:

    * Put my new work in a new git repository on linuxcnc.org,
      hostmot2-firmware.git

    * Add debian/ stuff to that for building the emc2-firmware packages
      on systems where Xilinx ISE 9.2 is available -- packages built in
      this way will be put on linuxcnc.org for installation with
      apt-get, and on linuxcnc.org and/or sourceforge.net in .tar.gz form
      for people who do not use debian-based systems

    * Remove hal/drivers/mesa-hostmot2/firmware from the emc2 source
      tree in the master branch

    * Remove the src/Makefile and debian/ stuff for installing and
      packaging the emc2-firmware packages

What are the benefits of this?

    * Reduce the size of an emc2 source tar.gz by about 3 megs (25%!)

    * Stop increasing the size of an initial git clone by a similar
      amount each time the hostmot2 firmwares are updated

    * Be certain that we know what source goes with mesa firmwares

    * emc2 and hostmot2-firmware releases need not be made in lock-step
      -- you won't have to download new hostmot2 firmwares with each
      emc2 release, or get a new emc2 release just for a hostmot2
      bugfix, new pinout, or other change

What problems are there?

    * There may be card-specific problems (like the 3x20 problem) until
      I have feedback from users with each card (however, Seb and I will
      have a chance to test a number of cards next weekend)

    * For technical reasons these firmwares are not compatible with
      current emc2.3 versions; if we find it desirable, we can add that
      compatibility to a future emc2.3 release.  For users of the
      packages, I believe that a line like 'Conflicts: emc2 (<<2.4.0)'
      will make sure the new firmwares aren't installed alongside a
      2.3.x system; after a future 2.3.x release such as 2.3.6 supports
      these firmwares, new firmwares can be issued which 'Conflicts:
      emc2 (<<2.3.6)'.  (Adding support in 2.3 looks as easy as merging
      commit ac4284af but I haven't tried it)

    * The no-cost ISE 9.2 does not support the 3s2000 fpga on the
      3x20-2000, so that card will not be supported.  however, there are
      not presently many reasons to buy this card for hostmot2 as the
      3x20-1000 has only about 1/3 of the chip resources used by a
      typical firmware (SV24, the firmware for 24 pwm + 24 encoders)

Why use a different git repository, instead of leaving it in emc2.git?
It makes the most sense to maintain a 1:1 relationship between debian
source packages and git repositories, but I don't want to force everyone
building an emc2 package to have Xilinx ISE installed.

Please let me know your thoughts in the next week.  Unless this thread
turns up some unforeseen problems, I will make the emc2.git changes
early next month (yes, fudging my own deadlines, but I want to make sure
this has some time for discussion and additional testing)

Jeff