2.1. Hammer Technologies

Hammer currently has open-source technology plugins in the hammer/technology folder. Other proprietary technology plugins cannot be made public without 3-way NDAs or special agreements with their respective foundries.

The structure of each technology plugin package is as follows:

  • hammer


      • __init__.py contains the tech class object and methods for PDK installation/extraction and getting hooks.

      • <name>.tech.json contains the static information about the technology. See the section Hammer Tech JSON for a guide.

      • defaults.yml contains the default tech-specific Hammer IR and Meta Variables. See the section Hammer Tech defaults.yml for a guide.


        • __init__.py (optional) can contain a technology’s implementation of an action. Commonly, this is used for the SRAM compilation action.

        • TOOL_NAME

          • __init__.py (optional) contains callable hook methods specific to the technology and tool, if there are too many to put in TECHNOLOGY_NAME/__init__.py.

Resources that are needed may go in this directory structure where necessary.

2.1.1. HammerTechnology Class

The HammerTechnology class is the base class that all technology plugins should inherit from and is defined in hammer/tech/__init__.py. Particularly useful methods are:

  • post_install_script: the plugin subclass should override this method to apply any non-default PDK installation steps or hotfixes in order to set up the technology libraries for use with Hammer.

  • read_libs: this is a particularly powerful method to read the libraries contained in the tech.json file and filter them using the filters also contained the same file. See the Library Filters section for details.

  • get_tech_<action>_hooks: these methods are necessary if tech–specific hooks are needed, and must return a list of hooks when a given tool name implementing the relevant action is called. Refer to the Extending Hammer with Hooks section for details about how to write hooks.