Claudio Talarico
Home
VLSI

More on Setting up and installing the required EDA softwares

Enable Windows Subsystem for Linux (WSL)


1. Prerequisites

  • WSL requires Windows 10, Version 1903 or higher, with Build 18362 or higher, for x64 systems, and Version 2004 or higher,
    with Build 19041 or higher, for ARM64 systems

  • To find your machine's architecture and Windows version/build number go to:

    • Settings > System > About

alt text 

2. Enable the Windows Subsystem for Linux feature

  • The easiest way to enable the feature is using the GUI

    • go to Start Menu, and search “Turn Windows feature on or off”

    • select Windows Subsystem for Linux and click OK

alt text 


3. After enabling Windows Subsystem for Linux, restart your computer when prompted

4. Install your Linux distribution of choice

  • Open the Microsoft Store and select the latest LTS Ubuntu Linux distribution available

5. Create a UNIX user

  • the first time you launch a Linux distribution in Windows, you will be prompted to create a UNIX username and password.

  • this UNIX username and password has no relationship to your Windows username and password, so to avoid any confusion use a different username
    (example: utalarico)

6. Update the Linux distribution 

sudo apt-get update && sudo apt-get upgrade -y && sudo apt-get dist-upgrade -y && sudo apt-get autoremove -y

The -y flag signifies automatic yes to any prompts that may come up in the command line

7. Accessing the Windows filesystem from WSL

  • To make it easier to access your Windows user directory, consider adding a symbolic link, such as: 

ln -s /mnt/c/Users/<windowsusername> ~/winhome

(example of windowsusername: ctalarico)

8. Starting up WSL

  • in general, to start using WSL, open up a PowerShell terminal and type wsl. If you’ve set up WSL correctly, you’ll enter a bash terminal running on
    the WSL distro of choice. From here, you can run any Linux commands you wish.

  • in our specific case, since we have installed mobaXterm we can also start the WSL terminal through MobaXterm

alt text 

9. Graphical Applications

  • To run Linux GUI applications using WSL, you must:

    • install an X server for Windows

    • configure bash to tell the GUIs applications to use the local X server

  • Method 1:

    • Don't do anything: take advantage of the Xserver provided by mobaXterm.

    • the configuration of the Xserver is directly handled by mobaxterm.

  • Method 2:

    • since to run graphical Linux applications, you need an X server, install VcXsrv.

    • VcXsrv is the only fully open source and up-do-date native X server for Windows.

    • download and run the latest installer, then locate the XLaunch shortcut in the Start Menu, and click it.

    • configure the bash shell to use the local X server:

in bash run:

echo "export DISPLAY=localhost:0.0" >> ~/.bashrc

and then to have the configuration changes take effect, restart the bash or run:

. ~/.bashrc

Installing magic


The skywater SKY130 PDK requires at least Magic VLSI version 8.3.25.
If the version of magic available through Ubuntu is adequate you can install it using sudo apt install magic.

To install the latest version compile and build magic from the source distribution

1. download the latest source distribution using git 

git clone https://github.com/RTimothyEdwards/magic.git git_magic

2. magic requires a number of supporting software packages

  • build-essential

  • flex

  • bison

  • m4

  • tcsh

  • csh

  • libx11-dev

  • tcl-dev

  • tk-dev

  • libcairo2-dev

  • libncurses-dev

  • blt

  • freeglut3

  • mesa-common-dev

  • libgl1-mesa-dev

  • libglu1-mesa-dev

To check what packages are installed use apt list package-name

To install the missing packages use sudo apt install package-name

The process of installing packages is quite empirical, and depends on the order in which you installed packages on you machine. This is because,
typically, whenever you install a software package, there is also a number of other dependent or recommended packages that will get installed with it.
For example installing the package flex does also install the package gcc that includes the compiler c99 (but this falls “under the radar”).

To check the dependencies of a package you can use apt show package-name or apt rdepends package-name

To check if a program belongs to a certain package you can use dpkg --search file-name or
if the file is not installed you can use apt-file search file-name

Example: 

dpkg --search c99

To check all the files in a package you can use apt-file list package-name

4. configure and install magic 

cd ~/git_magic
./configure --prefix=/home/<unixusername>/opt/magic
make
make install

The location of magic's binaries is ~/opt/magic/bin

5. create a .bash_profile file and add the location of the magic binaries to the PATH 

cd
.bash_profile
#!/usr/bin/bash

PATH=${PATH}

# Careful:
# when there is a .bash_profile the WSL terminal does not source .bashrc by default
source ~/.bashrc

# prevent "Warning: Missing charset in String to FontSet conversion"
export LC_ALL=C

# magic: binaries location
MAGIC_BIN=$HOME/opt/magic/bin

PATH="$MAGIC_BIN:$PATH"

# eliminate duplicates from the PATH
PATH=$(echo $PATH | gawk -F: '
{ for (i = 1; i <= NF; i++) arr[$i]; }
END { for (i in arr) printf "%s:" , i; printf "\n"; } ')

# and finally export the PATH
export PATH="$PATH"

Installing ngspice


The skywater SKY130 PDK requires at least ngspice version 34.
If the version of ngspice available through Ubuntu is adequate you can install it using sudo apt install ngspice.

To install the latest version download and compile ngspice from the source distribution

1. download ngspice-<xx>.tar.gz from here
(replace <xx> with the ngspice's version number you want to install, for example 38)

2. expand ngspice-<xx>.tar.gz into your home directory 

tar xvfz ngspice-<xx>-tar.gz -C ~

3. ngspice requires a number of packages

  • build-essential

  • flex

  • bison

  • libx11-6

  • libx11-dev

  • libxaw7

  • libxaw7-dev

  • fontconfig

  • libxft-dev

  • libxft2

  • libcairo2

  • libcairo2-dev

  • libxmu6

  • libxext-dev

  • libxext6

  • libxrender1

  • libxrender-dev

  • libtool

  • readline-common

  • libreadline-dev

  • gawk

To check what packages are installed use apt list package-name

To install the missing packages use sudo apt install package-name

4. browse to the location of ngspice's source files and configure and compile them 

cd ~/ngspice-<xx>
mkdir release
cd release
../configure --with-x --enable-xspice --disable-debug --enable-cider --with-readline=yes --enable-openmp --prefix=/home/<unixusername>/opt/ngspice
make 2>&1 | tee make.log
make install

The location of ngspice's binary is ~/opt/ngspice/bin

5. edit the .bash_profile file and add the ngspice's binary location to the PATH 

cd
.bash_profile
#!/usr/bin/bash

PATH=${PATH}

# Careful:
# when there is a .bash_profile the WSL terminal does not source .bashrc by default
source ~/.bashrc

# prevent "Warning: Missing charset in String to FontSet conversion"
export LC_ALL=C

# magic: binaries location
MAGIC_BIN=$HOME/opt/magic/bin

# ngspice: binaries location
NGSPICE_BIN=$HOME/opt/ngspice/bin

PATH="$NGSPICE_BIN:$MAGIC_BIN:$PATH"

# eliminate duplicates from the PATH
PATH=$(echo $PATH | gawk -F: '
{ for (i = 1; i <= NF; i++) arr[$i]; }
END { for (i in arr) printf "%s:" , i; printf "\n"; } ')

# and finally export the PATH
export PATH="$PATH"

“Aside” for Mac Users only


In this case, Windows 10 is a Virtual Machine. Since VMs do sometimes break (for example when the host OS X gets an update) it is not a good idea to save your work
on the VM. Instead, is advisable to store your work either on the Mac's hard drive or on a cloud storage service (e.g. OneDrive, Google Drive or iCloud drive).

The first option (saving the data on the Mac's hard drive) poses some visibility challenge. Since the Linux account (WSL) has no relationship to the Windows account,
the WSL account does not see the Mac OS Shared Folders provided through the VM mechanism.

Diversely, MobaXterm does not have any issue to access the Mac OS Shared Folders (this is because MobaXterm is a Linux emulator not a full Linux System environment)

Accessing Linux files (WSL) from windows 10 is also not an issue:

  • From the WSL command line interface run 

cd ~
explorer.exe .

  • This will launch File Explorer showing the current linux directory

> Network > wsl$ > Ubuntu > home > unixusername

1. How to make a folder on the Mac's hard drive accessible to WSL

a. on the Mac OS

  • select System Preferences > Users & Groups

  • add the windows OS user’ (example: ctalarico)

b. on the Mac OS

  • select System Preferences > Sharing

  • turn on the File Sharing Service

  • add the folder you want to share to the list of Shared Folder

  • add the windows user to the list of Users that can access the Shared Folders

  • shared folders can be accessed through samba at smb://some_address

c. on the Windows OS

  • select Explorer > This PC > Computer > Map Network drive

  • set the drive field to one of the available letters (example U:)

  • set the folder field to \\some_address\foldername

  • select reconnect to sign in

d. start the WSL terminal

  • run the command 

sudo mkdir -p /mnt/u
sudo mount -t drvfs U: /mnt/u

  • to make the mounting permanent edit the file /etc/fstab 

sudo vi /etc/fstab

  • add the following line 

U: /mnt/u drvfs defaults 0 0

  • reload the fstab using 

sudo mount -a

  • the owner of the mounted drive is root

  • to find out the uid and gid of the various users you can use the Linux command 

id

  • for the unix user (example: utalarico) uid=1000 and gid=1000

  • for the windows user (example: ctalarico) uid=1001 and gid=513

  • to change the ownership of the mounted drive use: 

sudo mount -t drvfs U: /mnt/u -o metadata,uid=1000,gid=1000

  • to learn how to modify the /etc/fstab for making the mounting permanent

    • look at how the previous command has modified the /etc/mtab or the /proc/mounts file

    • copy the corresponding line in the /etc/fstab file 

U: /mnt/u drvfs rw,relatime,uid=1000,gid=1000,case=off 0 0

  • reload the fstab using 

sudo mount -a

  • for convenience create a link to your mac's shared folder 

ln -s /mnt/u ~/machome

2. How to access data on a cloud storage service using WSL (example: iCloud)

  • open the Microsoft store and install iCloud

  • the files are mounted at: 

/mnt/c/Users/<windowsusername>/iCloudDrive/

  • for convenience create a link to iCloudDrive 

ln -s /mnt/c/Users/<windowsusername>/iCloudDrive ~/ihome

A few Linux commands we may need

  • to do administration as root 

sudo -s

  • to switch to root user 

sudo -i

  • to exit from the root user or the root administrative provileges 

exit

  • to check the linux release you are running 

lsb_release -a

  • to list in long format sorting by time in reverse lexographical order 

ls -ltr

  • to check if a package is installed and what version is available 

apt list [package_name]

  • to check the version of an available package 

apt show [package_name]

  • to create a compressed tarball file 

tar -czvf filename.tgz directory

  • to expand a compressed tarball file 

tar -xzvf filename.tgz

  • to expand a gz file 

gzip -dk filename.gz

Installing and “tuning up” xschem


For skywater 130nm PDK integration install at least xschem version 3.0.0
If the version of xschem available through Ubuntu is adequate you can install it using: 

sudo apt install xschem

Otherwise, download and compile the latest version from the source distribution

xschem requires a number of supporting software packages

  • build-essential

  • flex

  • bison

  • libx11-6

  • libx11-dev

  • libxcb1

  • libx11-xcb-dev

  • libxrender1

  • libxrender-dev

  • libcairo2

  • libcairo2-dev

  • libxpm4

  • libxpm-dev

  • tcl8.6

  • tcl8.6-dev

  • tk8.6

  • tk8.6-dev

  • gawk

  • graphicsmagick

  • vim-gtk3

To check what packages are installed use apt list package-name

To install the missing packages use sudo apt install package-name

Most packages are already presents on the systems since we already installed them for magic and ngspice

Here are the steps for installing, setting up and configuring xschem:

1. download xschem: 

cd
git clone https://github.com/StefanSchippers/xschem.git git_xschem

2. configure and install xschem 

cd ./git_xschem
./configure --prefix=/home/<unixusername>/opt/xschem
make
make install

the location of xschem's binaries (xschem and rawtovcd) is /home/<unixusername>/opt/xschem/bin

3. edit the .bash_profile file to add the xschem's binaries to the PATH 

cd
.bash_profile
#!/usr/bin/bash

PATH=${PATH}

# Careful:
# when there is .bash_profile the WSL terminal does not source .bashrc by default
source ~/.bashrc

# prevent "Warning: Missing charset in String to FontSet conversion"
export LC_ALL=C

# magic: binaries location
MAGIC_BIN=$HOME/opt/magic/bin

# ngspice: binaries location
NGSPICE_BIN=$HOME/opt/ngspice/bin

# xschem: binaries location
XSCHEM_BIN=$HOME/opt/xschem/bin

PATH="$XSCHEM_BIN:$NGSPICE_BIN:$MAGIC_BIN:$PATH"

# eliminate duplicates from the PATH
PATH=$(echo $PATH | gawk -F: '
{ for (i = 1; i <= NF; i++) arr[$i]; }
END { for (i in arr) printf "%s:" , i; printf "\n"; } ')

# and finally export the PATH
export PATH="$PATH"

4. xschem and tclsh

  • xschem relies on the use of tclsh in interactive mode

  • to use the tab key (for command completion) and the up and down arrow keys (for retrieving commands from the history buffer) we need to install the
    package tcl-tclreadline 

sudo apt install tcl-tclreadline

  • and add the following lines to ~/.tclshrc

.tclshrc
if {$tcl_interactive} {
    package require tclreadline
    ::tclreadline::Loop
}

5. setting up xschem

  • xschem default preferences are in the file xschemrc located in the directory xschem_install_dir/share/xschem/
    (with xschem_install_dir set to ~/opt/xschem)

  • to customize the default preferences xschem provides a special directory ~/.xschem/

  • copy the default xschmrc file into ~/.xschem/ and edit it according to your preferences

xschemrc (customizations)
...

# CT: 20211201
set XSCHEM_LIBRARY_PATH {}
append XSCHEM_LIBRARY_PATH $env(HOME_DIR)/ngs406/xSchems
append XSCHEM_LIBRARY_PATH :$env(HOME_DIR)/Lib406
append XSCHEM_LIBRARY_PATH :${XSCHEM_SHAREDIR}/xschem_library
append XSCHEM_LIBRARY_PATH :${XSCHEM_SHAREDIR}/xschem_library/devices
append XSCHEM_LIBRARY_PATH :$env(HOME)/share/pdk/sky130A/libs.tech/xschem
# end CT

...

# CT: 20211201
# set XSCHEM_START_WINDOW {sky130_tests/top.sch}
# end CT

...

# CT: 20211201
set netlist_dir $env(HOME_DIR)/ngs406/xSchems
# end CT

...

# CT: 20211201
# uncommented first two lines, added last two lines}
set hspice_netlist 1
set verilog_2001 1
set flat_netlist 0
set netlist_show 1
# CT end

...

# CT: 20211201
# SKYWATER PDK SPECIFIC VARIABLES
set SKYWATER_MODELS $env(HOME)/share/pdk/sky130A/libs.tech/ngspice
set SKYWATER_STDCELLS $env(HOME)/share/pdk/sky130A/libs.ref/sky130_fd_sc_hd/spice
# CT end

  • modify .bash_profile to add xschem's HOME_DIR location

.bash_profile
#!/usr/bin/bash

PATH=${PATH}

# Careful:
# when there is .bash_profile the WSL terminal does not source .bashrc by default
source ~/.bashrc

# prevent "Warning: Missing charset in String to FontSet conversion"
export LC_ALL=C

# magic: binaries location
MAGIC_BIN=$HOME/opt/magic/bin

# ngspice: binaries location
NGSPICE_BIN=$HOME/opt/magic/bin

# xschem: binaries location
XSCHEM_BIN=$HOME/opt/xschem/bin

# setting xschem's HOME_DIR variable
export HOME_DIR=$HOME/ihome

PATH="$XSCHEM_BIN:$NGSPICE_BIN:$MAGIC_BIN:$PATH"

# eliminate duplicates from the PATH
PATH=$(echo $PATH | gawk -F: '
{ for (i = 1; i <= NF; i++) arr[$i]; }
END { for (i in arr) printf "%s:" , i; printf "\n"; } ')

# and finally export the PATH
export PATH="$PATH"

  • to make sure xschem's variables are set according to you expectations

    • start xschem and in the tcl shell prompt type the following commands: 

puts $XSCHEM_LIBRARY_PATH
puts $XSCHEM_SHAREDIR
puts $USER_CONF_DIR
puts $SKYWATER_MODELS
puts $SKYWATER_STDCELLS
puts $netlist_dir
Response to the puts command (example)
/home/utalarico/ihome/ngs406/xSchems:/home/utalarico/ihome/Lib406:/home/utalarico/opt/xschem/share/xschem/xschem_library:/home/utalarico/opt/xschem/share/xschem/xschem_library/devices:/home/utalarico/share/pdk/sky130A/libs.tech/xschem

/home/utalarico/opt/xschem/share/xschem

/home/utalarico/.xschem

/home/utalarico/share/pdk/sky130A/libs.tech/ngspice

/home/utalarico/share/pdk/sky130A/libs.ref/sky130_fd_sc_hd/spice

/home/utalarico/ihome/ngs406/xSchems

  • for further details please look up the documentation and tutorials provided by xschem's author (Stefan Schippers)

6. Circuit simulation and visualization of the output waveforms
For the simulation and visualization of the outputs xschem provides the ability to interface with ngspice and gaw (Gtk Anaog Wave viewer).

7. Installing gaw
gaw (Gtk Analog Wave Viewer) does not come pre-packaged, so it must be installed from source, and in addition it requires the installation of the libgtk-3-dev package.

  • install the libgtk-3-dev package 

sudo apt-get install libgtk-3-dev

  • download gaw source's code from here
    the latest version of gaw (@ 2 Dec. 2021) is ver. 20200922

  • extract, configure and compile the source code 

tar zxvf gaw3-20200922.tar.gz
cd gaw-20200922
./configure
make
sudo make install

  • the gaw binary file is located at /usr/local/bin/gaw

  • the first time gaw gets started it creates a directory ~/.gaw containing the preference file gawrc

8. configure xschem for analog simulation (ngspice and gaw)

  • start xschem

  • go to Simulation > Configure simulators and tools

  • edit the configurations for ngspice, ngspice batch, and gaw viewer as follows:

alt text 

  • Click on Save Configuration to file
    the location of the configuration file is ~/.xschem/simrc

  • the meaning of the various variables used in the configuration settings is the following:

    • $N - netlist file full path (example: ~/ihome/ngs406/xSchems/tgate.spice)

    • $n - netlist file full path with extension chopped (example: ~/ihome/ngs406/xSchems/tgate)

    • $s - schematic name (example: tgate)

    • $d - netlist directory (example: ~/ihome/ngs406/xSchems)

    • for - more details lookup the file ~/opt/xschem/share/xschem/xschem.tcl

9. install the xschem's library for the skywater 130nm PDK

Instead of manually installing the xschem's skywater library from github (git clone https://github.com/StefanSchippers/xschem_sky130.git)
install it directly through the open_pdks as shown here.

The current (@ 3 Dec. 2021) xschem_sky130 examples use the model file locations installed by open_pdks

Install open_pdks and the skywater sky130 PDK


  • open_pdks aims to create the setups necessary to use open-source PDKs with open-source EDA tools (xschem, ngspice, magic, klayout, netgen, etc.)

  • open_pdks supports the Google/Skywater SKY130 open process

  • NOTE: for open_pdks to install the files required by the Magic, Magic must be installed !

  • use opendesign to install the sky130 PDK and organize the structure of the CAD tools 

git clone https://github.com/RTimothyEdwards/open_pdks.git git_open_pdks
cd ~/git_open_pdks
#./configure --enable-sky130-pdk=/home/<unixusername>/skywater-pdk \
#--with-sky130-variants=all --prefix=/home/<unixusername>
./configure --enable-sky130-pdk --with-sky130-variants=all --prefix=/home/<unixusername>
make
make install

The PDK gets installed at the location ~/share/pdk

Libraries in the SKY130 PDK are named using the following scheme:
<Process name>_<Library Source>_<Library Type>

  • process name:
    sky130 = skywater 130nm processs

  • library source:
    fd = skywater foundry

  • library type:
    sc = digital standard cells
    io = input/output and periphery cells
    pr = basic primitives
    hd = high density
    hvl = high voltage
    hdll = high density low leakage
    hs = high speed
    ms = medium speed
    ls = low speed
    lp = low power

make sure the xschem_sky130 library is installed correctly


  • create an example directory and browse to it 

mkdir -p ~/example_xschem_sky130
cd example_xschem_sky130

  • copy in the example directory the xschem initialization file available in the PDK 

cp ~/share/pdk/sky130A/libs.tech/xschem/xschemrc .

  • create an ngspice initialization file .spiceinit with the following lines:
    set ngbehavior=hs
    set ng_nomodcheck
    set color0=white
    set color1=black
    set xbrushwidth=2

  • start xschem

  • a few useful zoom commands and their shortcuts:

    • Zoom Full | F

    • Zoom In | Shift + Z

    • Zoom Out | Ctrl Z

    • Zoom Box | Z

  • select the cell test_nmos and hit the key E to descend into its schematic

  • double click the Netlist “button”

  • double click the Simulate “button”

Build your own xschem library


  • make a directory Lib406 (example: ~/ihome/Lib406)

  • copy your favorite symbols into the directory

  • in case you are not satisfied with the look of the existing symbols edit them

  • here is a sample Lib to get started with