## Intellectual Properties (IP)

IP files can be stored anywhere in your repository or in submodules. However, particular care must be taken to avoid that files generated by Vivado or Quartus are kept separated and not committed to the repository, unless you want to keep the IP in a locked status.

To achieve this, these simple rules must be followed:

- each ip file (.xci for Vivado) must be contained in a sub-folder called with the same name as the .xci file (extension excluded).
- only the ip file must be committed to the repository (e.g. `.xci` for Vivado, `.ip` for Quartus)
- a `.gitignore` file must be used to tell git to ignore all non-ip files, a template is provided in the `Templates` directory.

Basically for each IP in your project run:

```bash
  mkdir -p path_to_your_ips/ip_name/
  cp ../old_repo/ip_name.xci path_to_your_ips/ip_name/
```

Then you must add the `.xci` files to the .src list file you want, in this case we will use a separate file called `IP.src`. You can use the following script if you like:


```bash
  for i in $( ls path_to_your_ips/* ); do \
    echo $i/$i.xci >> Top/myproject/list/myproject.src;
  done
```

```{note}
There is no concept of library for the IPs, so we prefer to put them in a separate .src file. You can put them in the same list file as your other source files if you wish. Just open `Top/myproject/list/myproject.src` with a text editor and add them there.
```

As usual, you can check that the files are correctly picked up by regenerating the project `./Hog/CreateProject.sh myproject`
If you are satisfied with the changes, you can commit your work.

```bash
  git add path_to_your_ips
  git add Top/myproject/list/IP.src
  git commit -m "Adding IP Files"
```

### Keep the IP locked (Vivado only)
Sometimes you might want an IP to be kept in a locked status, for example, when you are using an older version of the IP and want to prevent Vivado to update it.
This can be achieved by committing to the repository the entire folder where the `.xci` file is located and by removing the dedicated `.gitignore`. Then, in your `.src` list file you can specify the *locked* property for your IP as following.

```bash
    IP/ip1.xci locked
```

You can achieve the same result, by unticking the *IS_MANAGED* property of your IP in the Vivado GUI.

##### IP initialisation files (.coe, .mif)

Please note that the `.gitignore` template provided by Hog adds constraints on the IP folder.
Out of all the files contained in *repo*/*IP*/, git will pick up only *.xci* files.
Files with different extensions will be ignored.
If you have *.coe* files for RAM initialization or analogous files please make sure that you store these files in a separate folder and point to them in the IP one by using a relative path.