|  | # CIIC Harness | 
|  |  | 
|  | A template SoC for Google SKY130 free shuttles. It is still WIP. The current SoC architecture is given below. | 
|  |  | 
|  | <p align=”center”> | 
|  | <img src="/doc/ciic_harness.png" width="75%" height="75%"> | 
|  | </p> | 
|  |  | 
|  |  | 
|  | ## Getting Started: | 
|  |  | 
|  | * For information on tooling and versioning, please refer to [this][1]. | 
|  |  | 
|  | Start by cloning the repo and uncompressing the files. | 
|  | ```bash | 
|  | git clone https://github.com/efabless/caravel.git | 
|  | cd caravel | 
|  | make uncompress | 
|  | ``` | 
|  |  | 
|  | Then you need to install the open_pdks prerequisite: | 
|  | - [Magic VLSI Layout Tool](http://opencircuitdesign.com/magic/index.html) is needed to run open_pdks -- version >= 8.3.60* | 
|  |  | 
|  | > \* Note: You can avoid the need for the magic prerequisite by using the openlane docker to do the installation step in open_pdks. This [file](https://github.com/efabless/openlane/blob/develop/travisCI/travisBuild.sh) shows how. | 
|  |  | 
|  | Install the required version of the PDK by running the following commands: | 
|  |  | 
|  | ```bash | 
|  | export PDK_ROOT=<The place where you want to install the pdk> | 
|  | make pdk | 
|  | ``` | 
|  |  | 
|  | Then, you can learn more about the caravel chip by watching these video: | 
|  | - Caravel User Project Features -- https://youtu.be/zJhnmilXGPo | 
|  | - Aboard Caravel -- How to put your design on Caravel? -- https://youtu.be/9QV8SDelURk | 
|  | - Things to Clarify About Caravel -- What versions to use with Caravel? -- https://youtu.be/-LZ522mxXMw | 
|  | - You could only use openlane:rc5 | 
|  | - Make sure you have the commit hashes provided here inside the [Makefile](./Makefile) | 
|  | ## Aboard Caravel: | 
|  |  | 
|  | Your area is the full user_project_wrapper, so feel free to add your project there or create a differnt macro and harden it seperately then insert it into the user_project_wrapper. For example, if your design is analog or you're using a different tool other than OpenLANE. | 
|  |  | 
|  | If you will use OpenLANE to harden your design, go through the instructions in this [README.md][0]. | 
|  |  | 
|  | Then, you will need to put your design aboard the Caravel chip. Make sure you have the following: | 
|  |  | 
|  | - [Magic VLSI Layout Tool](http://opencircuitdesign.com/magic/index.html) installed on your machine. We may provide a Dockerized version later.\* | 
|  | - You have your user_project_wrapper.gds under `./gds/` in the Caravel directory. | 
|  |  | 
|  | > \* **Note:** You can avoid the need for the magic prerequisite by using the openlane docker to run the make step. This [section](#running-make-using-openlane-magic) shows how. | 
|  |  | 
|  | Run the following command: | 
|  |  | 
|  | ```bash | 
|  | export PDK_ROOT=<The place where the installed pdk resides. The same PDK_ROOT used in the pdk installation step> | 
|  | make | 
|  | ``` | 
|  |  | 
|  | This should merge the GDSes using magic and you'll end up with your version of `./gds/caravel.gds`. You should expect hundred of thousands of magic DRC violations with the current "development" state of caravel. | 
|  |  | 
|  | ## Running Make using OpenLANE Magic | 
|  |  | 
|  | To use the magic installed inside Openlane to complete the final GDS streaming out step, export the following: | 
|  |  | 
|  | ```bash | 
|  | export PDK_ROOT=<The location where the pdk is installed> | 
|  | export OPENLANE_ROOT=<the absolute path to the openlane directory cloned or to be cloned> | 
|  | export IMAGE_NAME=<the openlane image name installed on your machine. Preferably openlane:rc5> | 
|  | export CARAVEL_PATH=$(pwd) | 
|  | ``` | 
|  |  | 
|  | Then, mount the docker: | 
|  |  | 
|  | ```bash | 
|  | docker run -it -v $CARAVEL_PATH:$CARAVEL_PATH -v $OPENLANE_ROOT:/openLANE_flow -v $PDK_ROOT:$PDK_ROOT -e CARAVEL_PATH=$CARAVEL_PATH -e PDK_ROOT=$PDK_ROOT -u $(id -u $USER):$(id -g $USER) $IMAGE_NAME | 
|  | ``` | 
|  |  | 
|  | Finally, once inside the docker run the following commands: | 
|  | ```bash | 
|  | cd $CARAVEL_PATH | 
|  | make | 
|  | exit | 
|  | ``` | 
|  |  | 
|  | This should merge the GDSes using magic and you'll end up with your version of `./gds/caravel.gds`. You should expect hundred of thousands of magic DRC violations with the current "development" state of caravel. | 
|  |  | 
|  | ## Required Directory Structure | 
|  |  | 
|  | - ./gds/ : includes all the gds files used or produced from the project. | 
|  | - ./def/ : includes all the def files used or produced from the project. | 
|  | - ./lef/ : includes all the lef files used or produced from the project. | 
|  | - ./mag/ : includes all the mag files used or produced from the project. | 
|  | - ./maglef/ : includes all the maglef files used or produced from the project. | 
|  | - ./spi/lvs/ : includes all the maglef files used or produced from the project. | 
|  | - ./verilog/dv/ : includes all the simulation test benches and how to run them. | 
|  | - ./verilog/gl/ : includes all the synthesized/elaborated netlists. | 
|  | - ./verilog/rtl/ : includes all the Verilog RTLs and source files. | 
|  | - ./openlane/`<macro>`/ : includes all configuration files used to run openlane on your project. | 
|  | - info.yaml: includes all the info required in [this example](info.yaml). Please make sure that you are pointing to an elaborated caravel netlist as well as a synthesized gate-level-netlist for the user_project_wrapper | 
|  |  | 
|  | ## Managment SoC | 
|  | The managment SoC runs firmware that can be used to: | 
|  | - Configure User Project I/O pads | 
|  | - Observe and control User Project signals (through on-chip logic analyzer probes) | 
|  | - Control the User Project power supply | 
|  |  | 
|  | The memory map of the management SoC can be found [here](verilog/rtl/README) | 
|  |  | 
|  | ## User Project Area | 
|  | This is the user space. It has limited silicon area (TBD, about 3.1mm x 3.8mm) as well as a fixed number of I/O pads (37) and power pads (10).  See [the Caravel  premliminary datasheet](doc/caravel_datasheet.pdf) for details. | 
|  | The repository contains a [sample user project](/verilog/rtl/user_proj_example.v) that contains a binary 32-bit up counter.  </br> | 
|  |  | 
|  | <p align=”center”> | 
|  | <img src="/doc/counter_32.png" width="50%" height="50%"> | 
|  | </p> | 
|  |  | 
|  | The firmware running on the Management Area SoC, configures the I/O pads used by the counter and uses the logic probes to observe/control the counter. Three firmware examples are provided: | 
|  | 1. Configure the User Project I/O pads as o/p. Observe the counter value in the testbench: [IO_Ports Test](verilog/dv/caravel/user_proj_example/io_ports). | 
|  | 2. Configure the User Project I/O pads as o/p. Use the Chip LA to load the counter and observe the o/p till it reaches 500: [LA_Test1](verilog/dv/caravel/user_proj_example/la_test1). | 
|  | 3. Configure the User Project I/O pads as o/p. Use the Chip LA to control the clock source and reset signals and observe the counter value for five clock cylcles:  [LA_Test2](verilog/dv/caravel/user_proj_example/la_test2). | 
|  |  | 
|  | [0]: openlane/README.md | 
|  | [1]: mpw-one-a.md |