coriolis/cumulus
Jean-Paul Chaput c131e7a948 Clean parameters for routing topologies. Improved 2RL- support.
Previously, the relevant NetBuilder and routing strategies where
directly guessed from the RoutingGauge traits. This is no longer
doable as the combinations increases. Now to configure both the
global and detailed router we need three "parameters" :

1. The routing gauge itself (tells which layers are in which
   directions) and how to make the VIAs.
2. The NetBuilder to use, they are identified by strings.
   Currently we support:
   * "HV,3RL+", for all SxLib derived standard cells.
   * "VH,2RL", for hybrid routing (over the cell, but terminals
     are also in the first RL).
   * "2RL-", for strict channel routing.
   * "VH,3RL+", an attempt for FreePDK 45, not optimized enough
     to be considered as usable.
3. The routing style, mostly affect the way the GCell grid will be
   built.
   * VH      : first RL is V.
   * HV      : first RL is H.
   * OTH     : Run in full over-the-cell mode (needs at least 3RL).
   * Channel : Run in *strict* channel routing mode (no routing over
               the standard cells).
   * Hybrid  : Create channels, but can use H tracks over the
               standard cells.

Thoses three parameters are partly overlapping and must be sets in
a consistent manner, otherwise strange results may occurs.

* New: CRL::RoutingGauge::getFirstRoutingGauge(), to get the lowest
    layer available for routing (not a PinOnly, not a PowerSupply).
* Change: In CRL::RoutingGauge::isHV() and isVH(), were previously
    always returning false when the gauge was 2RL only. Now, check
    on the first usable RL.
* Bug: In cumulus/plugins.block.configuration._loadRoutingGauge(),
    there was a bad computation of the deep RLs when the top layer
    was not defined. Occured for 2RL gauges only.
* Bug: In Anabatic::RpsInRow::slacken() (LayerAssign), forgotten curly braces
    in the test to skip METAL2 terminals.
* Change: In Etestian::BloatChannel::getDx(), adjust the bloating
    policy to converge on Arlet6502. Always ensure that there is
    a 50% ratio between terminal used V-tracks and free ones.
      If there is more than 80% of terminals, add one more track.
* Bug: In AnabaticEngine & KatanaEngine, KatanaEngine is a derived
    class of AnabaticEngine.  They uses Anabatic::Configuration
    and Katana::Configuration that also derives from each other.
    I though I had made one configuration attribute in the base
    class that was using the right Configuration. But no. I did
    have two configurations attributes, one in AnabaticEngine and
    one in KatanaEngine, the later "shadowing" the former. As a
    results, parameters modified in AnabaticEngine, *after* the
    initial creation of the tool *where never seen* at Katana
    level (due to it's own duplicate). What a mess.
      Now there is only one attribute in the *base* class Anabatic,
    which is created through a new virtual function _createConfiguration()
    called in _postCreate() which allocate the right Configuration
    according to the dynamic type of the tool (KatanaEngine).
      In KatanaEngine, access the configuration through the
    attribute (_configuration) and not the accessor (getConfiguration()).
* Bug: In KatanaEngine, no longer directly use the _configuration attribute
    (which is not accessible anyway) but the getConfiguration() accessor.
    The accessor perform a static_cast from the Super::getConfiguration()
    into Katana::Configuration.
      Complete cleanup of the various configuration accessors.
* New: AnabaticEngine::setupNetBuilder(), perform an early check
    of the requested NetBuilderStyle. The NetBuilderStyle is just a
    string that will be matched against the (hard-coded) supported
    NetBuilders. Then check the topological characteristics against
    the capabilities of the gauge (HV, VH and so on).
      Still a bit too hard-coded for now.
      This function has been split from AnabaticEngine::_loadGrByNet().
* Change: AnabaticEngine::isChannelStyle() renamed from isChannelMode().
* New: In Anabatic::Configuration, two new attributes to select the
    topology and routing style:
      - _netBuilderStyle to explicitely select the NetBuilder to use.
        It's a string, which is provided by each NetBuilder.
      - _routingStyle to define how the overall routing will work.
        It's a set of flags (StyleFlags):
	* VH      : first RL is V.
	* HV      : first RL is H.
	* OTH     : Run in full over-the-cell mode (needs at least 3RL).
	* Channel : Run in *strict* channel routing mode (no routing over
	            the standard cells).
	* Hybrid  : Create channels, but can use H tracks over the
	            standard cells.
* New: In anabatic/Constants, add StyleFlags to define how the router
    should operate (see above).
* Bug: In Anabatic::GCell, in CTOR, no reason to set up the HChannelGCell flag.
* Bug: In Anabatic::GCell::updateDensity(), when computing layers non contiguous
    saturation, do not systematically skip RL 0, but only if it's PinOnly.
* Change: In Anabatic::NetBuilder, rename isTwoMetal by isStrictChannel.
* Change: In Anabatic::NetBuilderHV, rename doRp_AccessNorthPin() in
    doRp_AccessNorthSouthPin(). More accurate.
* Bug: In NetBuilderHV::_do_1G_xM1_1PinM2(), the wires to connect the M1
    terminals where created *twice*. Uterly stupid, there where placed in
    overlap by the router!
* New: In AnabaticEngine, new accessors to the NetBuilderStyle and
    RoutingStyle, proxies towards Configuration.
* Bug: In Manipulator::relax(), if there are two doglegs to be done, but
    they are in the same GCell, only do one (the conflicting interval)
    is short.
* Change: In Katana::Session, rename isChannelMode() into isChannelStyle().
* Change: In TrackSegment::isUnbreakable() and isStrap(), return false
    when the base segment is a *weak global* (aligned with a global one).
* Change: In Katana::Row::createChannel(), correctly distinguish between
    *strict channel* style and *hybrid* style. Tag the GCells as std cells
    row or channels only in the former case.
2022-11-26 13:07:12 +01:00
..
src Clean parameters for routing topologies. Improved 2RL- support. 2022-11-26 13:07:12 +01:00
CMakeLists.txt Bump minimum CMake version 2021-10-15 13:38:38 +01:00