VHDL Producer

Install

Install using pip (>= 19.0)

pip install git+https://github.com/cms-l1-globaltrigger/tm-vhdlproducer.git@2.23.0

Build from source

Basic development instructions.

git clone https://github.com/cms-l1-globaltrigger/tm-vhdlproducer.git
cd tm-vhdlproducer
git checkout master

Create virtual environment.

python3 -m venv env
. env/bin/activate

Install package for local development.

pip install --upgrade pip
pip install --editable .

Basic usage

Generate VHDL output from XML trigger menu.

tm-vhdlproducer --modules <n> -d|--dist <n> [--ratio <f>]
               [--sorting asc|desc] [--constraint <type:modules>]
               [--dryrun] <menu>

Distribute to multiple modules

Example for distributing on two modules:

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1

This will create a directory L1Menu_sample-d1/ in the current directory.

Specifying distribution number

To specify the distribution number use the --dist flag. For example

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 2  # set distribution number to 2

will write the output to /tmp/L1Menu_sample-d2/.

Specify sort order for algorithm distribution

Example for reversing algorithm distribution descending order (default ascending):

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --sorting desc

This will distribute algorithms from high to low payload weight.

Specifying output location

To specify a different output location use the --output flag. For example

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --output /tmp

will write the output to /tmp/L1Menu_sample-d1/.

Optimizations

Shadow ratio

Adjust the shadow ratio to optimize the distribution of algorithms. A good starting point is a ratio between 0.0 and 0.25, although it depends heavily on the individual menu's content.

The shadow ratio controls what algorithms will be packed together in a module. Using a ratio of 0.5 means that all algorithms that contain at least 50 % of the same condition instances will be placed on the same module. Practical tests showed that this approach does not guarantee the most efficient distribution and should be used carefully (consider it as experimental). It is advised to start with a ratio of 0.0 and verify if higher ratios (up to 0.25) improve the chip resource usage.

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --ratio .25  # set ratio to 0.25

Condition constraints

To limit certain condition types to a subset of modules (or just a single module) use the --constraint argument. Limit a condition type to a single module

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --constraint ext:0  # limit external conditions to module 0

or to a subset of modules

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --constraint ext:2,4-6  # limit external conditions to modules 2, 4, 5 and 6

List of supported condition constraints:

• ext: external conditions
• zdc: both ZDC+ and ZDC- conditions

Dryrun

To try out different optimizations use the --dryrun flag to prevent writing output to the filesystem.

tm-vhdlproducer L1Menu_sample.xml --modules 2 --dist 1 --dryrun

Generated output

L1Menu_sample-d1/
 +-- doc/
 |    +-- L1Menu_sample-d1.html
 |    `-- L1Menu_sample-d1.twiki
 +-- testvectors/
 +-- vhdl/
 |    +-- module_0/
 |    |    `-- src/
 |    |         `-- *.vhd
 |    `-- ...
 +-- xml/
 |    `-- L1Menu_sample-d1.xml
 `-- tm-vhdlproducer.log

Documentation

A TWiki page template and a HTML menu documentation is also written to the doc/ directory in the output location.

Logging

All messages printed to the screen are written to a log file in the output location (e.g. L1Menu_sample/tm-vhdlproducer.log).

VHDL template hierarchy

VHDL template hierarchy for condition instances located in templates/vhdl/instances.