Coriolis User's Guide

The actively developed branch

The devel_anabatic branch is now closed and we go back to a more classical scheme where master is the stable version and devel the development one.

The Coriolis git repository is https://gitlab.lip6.fr/vlsi-cad/coriolis.git

Installing on RedHat or compatible distributions

1. Install or check that the required prerequisites are installed :

   dummy@lepka:~> yum install -y git cmake bison flex gcc-c++ libstdc++-devel  \
                                 binutils-devel                                \
                                 boost-devel boost-python boost-filesystem     \
                                 boost-regex  boost-wave                       \
                                 python-devel libxml2-devel bzip2-devel        \
                                 qt-devel
   

The packages qwt and qwt-devel are not provided by any standard repository (like epel). You may download them from the LIP6 Addons Repository Then run:

dummy@lepka:~> yum localinstall -y qwt-6.1.2-4.fc23.x86_64.rpm        \
                                   qwt-devel-6.1.2-4.fc23.x86_64.rpm  # Qwt for Qt 4.

You may also install them directly (whithout an intermediate download):

dummy@lepka:~> yum install -y http://ftp.lip6.fr/pub/linux/distributions/slsoc/soc/7/addons/x86_64/RPMS/qwt-6.1.2-4.fc23.x86_64.rpm \
                              http://ftp.lip6.fr/pub/linux/distributions/slsoc/soc/7/addons/x86_64/RPMS/qwt-devel-6.1.2-4.fc23.x86_64.rpm

2. Install the unpackaged prerequisites. Currently, only RapidJSON.

   dummy@lepka:~> mkdir -p ~/coriolis-2.x/src/support
   dummy@lepka:support> cd ~/coriolis-2.x/src/support
   dummy@lepka:support> git clone http://github.com/miloyip/rapidjson
   

3. Create the source directory and pull the git repository:

   dummy@lepka:~> mkdir -p ~/coriolis-2.x/src
   dummy@lepka:src> cd ~/coriolis-2.x/src
   dummy@lepka:src> git clone https://gitlab.lip6.fr/vlsi-cad/coriolis.git
   

4. Build & install:

   dummy@lepka:src> cd coriolis
   dummy@lepka:coriolis> git checkout devel
   dummy@lepka:coriolis> ./bootstrap/ccb.py --project=support  \
                                            --project=coriolis \
                                            --make="-j4 install"
   

dummy@lepka:coriolis> ./bootstrap/ccb.py --project=support  \
                                         --project=coriolis \
                                         --doc --make="-j1 install"

Under rhel6 or clones, you must build using the devtoolset, the version is to be given as argument:

dummy@lepka:coriolis> ./bootstrap/ccb.py --project=coriolis \
                                         --devtoolset=8 --make="-j4 install"

If you want to use Qt 5 instead of Qt 4, modify the previous steps as follows:

• At step 1, do not install the qt 4 related development package (qt4-devel), but instead:

  dummy@lepka:~> yum install -y qt5-qtbase-devel qt5-qtsvg-devel              # Qt 5.
  

  The package qwt-qt5-devel and it's dependency qwt-qt5 are not provided by any standard repository (like epel). You may download them from the LIP6 Addons Repository Then run:

  dummy@lepka:~> yum localinstall -y qwt-qt5-6.1.2-4.fc23.x86_64.rpm        \
                                     qwt-qt5-devel-6.1.2-4.fc23.x86_64.rpm  # Qwt for Qt 5.
  

• At step 4, add a --qt5 argument to the ccb.py command line.

• The Python scripts that make use of PyQt in crlcore and cumulus must be edited to import PyQt5 instead of PtQt4 (should find a way to automatically switch between the two of them).

The complete list of ccb functionalities can be accessed with the --help argument. It also may be run in graphical mode (--gui).

Building a Debug Enabled Version

The Release.Shared default version of the Coriolis is built stripped of symbols and optimized so that it makes analysing a core dump after a crash difficult. In the (unlikely) case of a crash, you may want to build, alongside the optimized version, a debug one which allows forensic examination by gdb (or valgrind or whatever).

Run again ccb.py, adding the --debug argument:

dummy@lepka:coriolis> ./bootstrap/ccb.py --project=support  \
                                         --project=coriolis \
                                         --make="-j4 install" --debug

As cgt is a Python script, the right command to run gdb is:

dummy@lepka:work> gdb python core.XXXX

Installing on Debian 9, Ubuntu 18 or compatible distributions

First, install or check that the required prerequisites are installed:

dummy@lepka:~> sudo apt-get install -y build-essential binutils-dev                     \
                                       git cmake bison flex gcc python-dev              \
                                       libboost-all-dev libboost-python-dev             \
                                       zlib1g-dev libxml2-dev rapidjson-dev libbz2-dev

To use with Qt 4:

dummy@lepka:~> sudo apt-get install -y qt4-dev-tools libqwt-dev python-qt4

To use with Qt 5:

dummy@lepka:~> sudo apt-get install -y qtbase5-dev libqt5svg5-dev libqwt-qt5-dev \
                                       python-pyqt5

Second step is to create the source directory and pull the git repository:

dummy@lepka:~> mkdir -p ~/coriolis-2.x/src
dummy@lepka:src> cd ~/coriolis-2.x/src
dummy@lepka:src> git clone https://gitlab.lip6.fr/vlsi-cad/coriolis.git

Third and final step, build & install:

dummy@lepka:src> cd coriolis
dummy@lepka:coriolis> git checkout devel
dummy@lepka:coriolis> ./bootstrap/ccb.py --project=coriolis \
                                         --make="-j4 install"

Additionnal Requirement under MacOS

Coriolis makes use of the boost::python module, but the MacPorts boost seems unable to work with the Python bundled with MacOS. So you have to install both of them from MacPorts:

dummy@macos:~> port install boost +python27
dummy@macos:~> port select python python27
dummy@macos:-> export DYLD_FRAMEWORK_PATH=/opt/local/Library/Frameworks

The last two lines tell MacOS to use the Python from MacPorts and not from the system.

Then proceed with the generic install instructions.

Stratus Netlist Capture

Stratus is the replacement for GenLib procedural netlist capture language. It is designed as a set of Python classes, and comes with it's own documentation (Stratus Documentation)

The Hurricane Data-Base

The Alliance flow is based on the mbk data-base, which has one data-structure for each view. That is, Lofig for the logical view and Phfig for the physical view. The place and route tools were responsible for maintaining (or not) the coherency between views. Reflecting this weak coupling between views, each one was stored in a separate file with a specific format. The logical view is stored in a vst file in vhdl format and the physical in an ap file in an ad-hoc format.

The Coriolis flow is based on the Hurricane data-base, which has a unified structure for logical and physical view. That data structure is the Cell object. The Cell can have any state between pure netlist and completly placed and routed design. Although the memory representation of the views has deeply changed we still use the Alliance files format, but they now really represent views of the same object. The point is that one must be very careful about view coherency when going to and from Coriolis.

As for the second release, Coriolis can be used only for three purposes :

• Placing a design, in which case the netlist view must be present.
• Routing a design, in that case the netlist view and the layout view must be present and layout view must contain a placement. Both views must have the same name. When saving the routed design, it is advised to change the design name otherwise the original unrouted placement in the layout view will be overwritten.
• Viewing a design, the netlist view must be present, if a layout view is present it still must have the same name but it can be in any state.

Synthetizing and loading a design

Coriolis supports several file formats. It can load all file format from the Alliance toolchain (.ap for layout, behavioural and structural vhdl .vbe and .vst), BLIF netlist format as well as benchmark formats from the ISPD contests.

It can be compiled with LEF/DEF support, although it requires acceptance of the SI2 license and may not be compiled in your version of the software.

Etesian -- Placer

The Etesian placer is a state of the art (as of 2015) analytical placer. It is within 5% of other placers' solutions, but is normally a bit worse than ePlace. This Coriolis tool is actually an encapsulation of Coloquinte which is the placer.

The placement area is defined by the top cell abutment box.

When placing a complete hierarchy, the abutment boxes of the cells (models) other than the top cell are set identical to the one of the top cell and their instances are all placed at position (0,0,ID). That is, all the abutments boxes, whatever the hierarchical level, define the same area (they are exactly superposed).

We choose this scheme because the placer will see all the instances as virtually flattened, so they can be placed anywhere inside the top-cell abutment box.

The placement area is computed using the etesian.aspectRatio and etesian.spaceMargin parameters only if the top-cell has an empty abutment box. If the top-cell abutment box has to be set, then it is propagated to all the instances models recursively.

Once a placement has been done, the placer cannot reset it (will be implemented later). To perform a new placement, you must restart cgt. In addition, if you have saved the placement on disk, you must erase any .ap file, which are automatically reloaded along with the netlist (.vst).

Etesian supports standard cells and fixed macros. As for the Coriolis 2.1 version, it doesn't support movable macros, and you must place every macro beforehand. Timing and routability analysis are not included either, and the returned placement may be unroutable.

Katana -- Global Router

The quality of Katana global routing solutions are equivalent to those of FGR 1.0. For an in-depth description of Katana algorithms, you may download the thesis of D. Dupuis avalaible from here~: Knik Thesis (Knik has been rewritten as part of Katana, the algorithms remains essentially the same).

The global router is now deterministic.

Katana -- Detailed Router

Katana no longer suffers from the limitations of Nero. It can route big designs as its runtime and memory footprint is almost linear (with respect to the number of gates). It has successfully routed design of more than 150K gates.

After each run, Katana displays a set of completion ratios which must all be equal to 100% or (NNNN+0) if the detailed routing has been successfull. In the event of a failure, on a saturated design, you may tweak the three following configuration parameters:

1. katana.hTrackReservedLocal, the number of track reserved for local routing, that quantity is substracted from the edge capacities (global routing) to give a sense of the cluttering inside the GCells.
2. katana.vTrackReservedLocal, same as above.
3. etesian.spaceMargin, increases the free area of the overall design so the routing density decrease.

The idea is to increase the horizontal and vertical local track reservation until the detailed router succeeds. But in doing so we make the task of the global router more and more difficult as the capacity of the edges decreases, and at some point it will fail too. So this is a balance.

Routing a design is done in four ordered steps:

1. Detailed pre-route P&R → Step by Step → Detailed PreRoute
2. Global routing P&R → Step by Step → Global Route
3. Detailed routing P&R → Step by Step → Detailed Route
4. Finalize routing P&R → Step by Step → Finalize Route

It is possible to supply to the router a complete wiring for some nets that the user wants to be routed according to a specific topology. The supplied topology must respect the building rules of the Anabatic database (contacts must be, terminals, turns, h-tee & v-tee only). During the first step Detailed Pre-Route the router will solve overlaps between the segments, without making any dogleg. If no pre-routed topologies are present, this step may be ommited. Any net routed at this step is then fixed and become unmovable for the later stages.

After the detailed routing step the Katana data-structure is still active (the Hurricane wiring is decorated). The finalize step performs the removal of the Katana data-structure, and it is not advisable to save the design before that step.

You may visualize the density (saturation) of either the edges (global routing) or the GCells (detailed routing) until the routing is finalized. Special layers appear to that effect in the The Layers&Go Tab.

Executing Python Scripts in Cgt

Python/Stratus scripts can be executed either in text or graphical mode.

A Python/Stratus script must contain a function called scriptMain() with one optional argument, the graphical editor into which it may be running (will be set to None in text mode). The Python interface to the editor (type: CellViewer) is limited to basic capabilities only.

Any script given on the command line will be run immediatly after the initializations and before any other argument is processed.

For more explanation on Python scripts see Python Interface to Coriolis.

Printing & Snapshots

Printing or saving into a pdf is fairly simple, just use the File -> Print menu or the CTRL+P shortcut to open the dialog box.

The print functionality uses exactly the same rendering mechanism as for the screen, beeing almost WYSIWYG. Thus, to obtain the best results it is advisable to select the Coriolis.Printer look (in the Controller), which uses a white background and well suited for high resolutions 32x32 pixels patterns

There is also two modes of printing selectable through the Controller Settings -> Misc -> Printer/Snapshot Mode:

Memento of Shortcuts in Graphic Mode

The main application binary is cgt.

Category	Keys	Action
Moves	Up, Down Left, Right	Shifts the view in the according direction
Fit	f	Fits to the Cell abutment box
Refresh	CTRL+L	Triggers a complete display redraw
Goto	g	apperture is the minimum side of the area displayed around the point to go to. It's an alternative way of setting the zoom level
Zoom	z, m	Respectively zoom by a 2 factor and unzoom by a 2 factor
	Area Zoom	You can perform a zoom to an area. Define the zoom area by holding down the left mouse button while moving the mouse.
Selection	Area Selection	You can select displayed objects under an area. Define the selection area by holding down the right mouse button while moving the mouse.
	Toggle Selection	You can toggle the selection of one object under the mouse position by pressing CTRL and pressing down the right mouse button. A popup list of what's under the position shows up into which you can toggle the selection state of one item.
	S	Toggle the selection visibility
Controller	CTRL+I	Show/hide the controller window. It's the Swiss Army Knife of the viewer. From it, you can fine-control the display and inspect almost everything in your design.
Rulers	k, ESC	One stroke on k enters the ruler mode, in which you can draw one ruler. You can exit the ruler mode by pressing ESC. Once in ruler mode, the first click on the left mouse button sets the ruler's starting point and the second click the ruler's end point. The second click exits automatically the ruler mode.
	K	Clears all the drawn rulers
Print	CTRL+P	Currently rather crude. It's a direct copy of what's displayed in pixels. So the resulting picture will be a little blurred due to anti-aliasing mechanism.
Open/Close	CTRL+O	Opens a new design. The design name must be given without path or extention.
	CTRL+W	Closes the current viewer window, but does not quit the application.
	CTRL+Q	CTRL+Q quits the application (closing all windows).
Hierarchy	CTRL+Down	Goes one hierarchy level down. That is, if there is an instance under the cursor position, loads its model Cell in place of the current one.
	CTRL+Up	Goes one hierarchy level up. If we have entered the current model through CTRL+Down reloads the previous model (the one in which this model is instanciated).

Cgt Command Line Options

Appart from the obvious --text options, all can be used for text and graphical mode.

Some Examples :

• Run both global and detailed router, then save the routed design:

  > cgt -v -t -G -R --cell=design --save-design=design_r
  

Miscellaneous Settings

The Look Tab

You can select how the layout will be displayed. There is a special one Printer.Coriolis specifically designed for Printing & Snapshots. You should select it prior to calling the print or snapshot dialog boxes.

The Filter Tab

The filter tab let you select what hierarchical levels of your design will be displayed. Hierarchy level are numbered top-down: the level 0 corresponds to the top-level cell, the level one to the instances of the top-level Cell and so on.

There are also check boxes to enable/disable the processing of Terminal Cell, Master Cells and Components. The processing of Terminal Cell (hierarchy leaf cells) is disabled by default when you load a hierarchical design and enabled when you load a single Cell.

You can choose what kind of form to give to the rubbers and the type of unit used to display coordinates.

The Layers&Go Tab

Control the individual display of all layers and Gos.

• Layers correspond to true physical layers. From a Hurricane point of view they are all the BasicLayers (could be matched to GDSII).
• Gos stands from Graphical Objects, they are drawings that have no physical existence but are added by the various tools to display extra information. One good exemple is the density map of the detailed router, to easily locate congested areas.

For each layer/Go there are two check boxes:

• The normal one triggers the display.
• The red-outlined allows objects of that layer to be selectable or not.

The Netlist Tab

The Netlist tab shows the list of nets... By default the tab is not synched with the displayed Cell. To see the nets you must check the Sync Netlist checkbox. You can narrow the set of displayed nets by using the filter pattern (supports regular expressions).

A very useful feature is to enable the Sync Selection, which will automatically select all the components of the selected net(s). You can select multiple nets. In the figure the net auxsc35 is selected and is highlighted in the Viewer.

The Selection Tab

The Selection tab lists all the components currently selected. They can be filtered thanks to the filter pattern.

Used in conjunction with the Netlist Sync Selection you will all see all the components part of net.

In this list, you can toggle individually the selection of component by pressing the t key. When unselected in this way a component is not removed from the the selection list but instead displayed in red italic. To see where a component is you may make it blink by repeatedly press the t key...

The Inspector Tab

This tab is very useful, but mostly for Coriolis developpers. It allows to browse through the live DataBase. The Inspector provides three entry points:

• DataBase: Starts from the whole Hurricane DataBase.
• Cell: Inspects the currently loaded Cell.
• Selection: Inspects the object currently highlighted in the Selection tab.

Once an entry point has been activated, you may recursively expore all its fields using the right/left arrows.

The Settings Tab

Here comes the description of the Settings tab.