This is Project Shodan, a project to research the fusion of novel hardware and software architectures to produce a low-power, ambient AI core. For more information, see our internal site.
We've stored our code in Gerrit, and like the Android developers before us, we use repo to manage the projects in our Gerrit repositories.
To get started, first make sure you have a Git login for all our projects by going to googlesource.com/new-password and pasting the provided script into a terminal.
Now you need to pull down a copy of the repo tool from our public facing sites and add it to your path:
mkdir -p bin export PATH=$PATH:$HOME/bin curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo chmod a+x ~/bin/repo
Make sure you've initialized git with your name and email address, and have configured it properly for fetching the sources:
git config --global user.name "Your Name" git config --global user.email "you@example.com"
Once you‘ve done this, you’re actually ready to check out the sources. Make a new directory where you'd like it to live, and initialize repo with the current release branch.
repo init -u https://spacebeaker.googlesource.com/shodan/manifest -g default,internal --no-use-superproject repo sync -j$(nproc)
Development for shodan requires that the necessary tools and prerequisites be installed.
To setup the build system:
source build/setup.sh
Install the prerequisites:
m prereqs
Install the tools used for development:
m tools
In general, working with repo is relatively simple:
repo start ${TOPICNAME}git add -A and commit with git commit.repo upload --re ${REVIEWER} --cc ${CC_LIST}repo sync -j$(nproc) to update.repo prune to remove your topic branch.For more information on how to use repo and git effectively, take a look at the official documentation.
In the Shodan project, we follow a “sticky +2” policy.
What this means is that you must get a +2 Code Review from a peer, or a TL. Gerrit will automatically pass any +2 Code Review scores you receive when you upload a patchset with minor changes. This policy is in place so that we can quickly get through code review and get our code submitted without requiring lots of round-trips with your reviewers.
If you change significant parts of the CL post-+2, please ask for additional review from your peers in a reply. Note: two +1s does not count as a +2!
You can‘t self-+2 your own CL, no matter the urgency or how simple the change is! This policy ensures the code change is peer reviewed, and prevent us from getting in trouble with security/compliance. If you don’t know who to send a CL to, put one of the TLs on the review list, and they'll redirect it appropriately, or review your change.
As a reviewer, please use good judgement to help the team keep the good momentum: If you provide a +1 score, please note in your comment who should provide the +2; if your comments are minor changes about style, format, etc., and not related to the functionality of the code, please provide +2 so the code owner can address the comments and submit the code without further review.
At the time of this writing, the TLs are:
Cindy Liu <hcindyl@> June Tate-Gans <jtgans@> Bangfei Pan <pbf@> Steve Xu <stevexu@>
Finally, if you can't get one of the above people, please put Kai Yick <kingkai@> on the review line.
Special note if you're listed above: you still must get your +2 from someone else -- we need the TLs to lead by example and demonstrate the appropriate behavior.
repo sync -j$(nproc)
Then if you have any outstanding branches, a repo rebase will help.
To upload a branch to gerrit for review, do this:
repo upload --re reviewer1,reviewer2 --cc email@host.com,email2@host2.com
Reviewers can be specified as usernames or full email addresses, likewise for --cc.
Repo will then output a URL for you to visit that allows you to make comments and abandon and merge the changes into the repository. To make changes during the review process, make your changes to the files, then:
git add -A # To add the files you've changed git commit --amend # To update the previous change repo upload -t --re ${REVIEWER} --cc ${CC_LIST} # To upload the change to Gerrit for review
Our layout is pretty simple:
Contains build scripts for the whole tree. This is effectively just an orchestration layer to make building the whole shebang easier. Each subtree may have its own build systems and have their own ways of building.
The cached cross-compilation toolchain, including rust and RISC-V GCC/LLVM toolchain.
Contains continuous integration scripts and tooling for Jenkins, our CI/CD tool.
Lots of extra documentation (we hope) about how the repo is laid out, how the build system works, code reviews, licensing, etc.
Contains all of the source code and RTL required to build the Shodan hardware, as well as simulate it in Verilator.
Security core.
System management controller (SMC).
Vector core for ML acceleration.
Operating system software for the SMC; including seL4 kernel & CAmkES framework, and custom CAmkES components that support Shodan (or maybe KataOS) applications.
The repo manifest used to glue all the git repositories together.
Contains utility scripts to help automate a few things.
Contains tools and src for simulators (Renode and Verilator) of the shodan system.
Contains the source code of applications running in all shodan cores.
TODO: add more details
Bootstrap for System Management Controller, Security Core, and Vector Core. This is the first software to run after reset; it does low-level hardware setup and starts TockOs (SC) and seL4 (SMC).
pigweed frameworks. Currently it is used for vector core functional tests.
The operating system running on the Security Core.
Springbok BSP, as well as the RVV instruction functional tests.
Springbok IREE application. It builds IREE runtime applications for ML models using IREE libraries and Spingbok BSP.
Contains the src to build the RISCV QEMU emulator, and IREE toolchain for ML models.
The ML executable is built with IREE workflow, targeted to RISCV 32-bit bare-metal config.
To build the IREE targets:
m iree
The IREE compiler sits in out/host/iree_compiler, while the runtime library/example sits in out/springbok_iree. To run the toy example (four-element vector element-wise multiplication) for testing:
sim_springbok out/springbok_iree/samples/simple_vec_mul/simple_int_vec_mul_embedded_sync
The output should be shown as:
21:27:11.0241 [INFO] cpu2: simprint: "INFO |simple_vec_mul finished successfully", 0 (0x0) 21:27:11.0248 [INFO] cpu2: simprint: "main returned: ", 0 (0x0)
(Enter quit or q to exit the Renode simulation)
The simulator used for Shodan is Renode. The configuration for the Shodan system is sim/config/platforms/shodan.repl, while and starting script is in sim/config/shodan.resc
To run the full system simulation, build the default target:
m
After all the artifacts are bulit, the Renode simulation session automatically starts, and you should see the secured core and SMC booted
10:40:14.6784 [INFO] uart1: [output] init_kernel() 10:40:14.6807 [INFO] uart1: [output] Init local IRQ 10:40:14.6831 [INFO] uart1: [output] Bootstrapping kernel 10:40:14.6842 [INFO] uart1: [output] Initialing PLIC... 10:40:14.7028 [INFO] uart0: [output] OpenTitan initialisation complete. Entering main loop 10:40:14.7066 [INFO] uart0: [output] Woo Tock! 10:40:14.7346 [INFO] uart0: [output] Hello Tock World 10:40:15.8820 [INFO] uart1: [output] Booting all finished, dropped to user space
At this point, you should be able to connect to the SMC debug console.
Install socat to your machine
sudo apt install socat
In a new shell session, launch the debug console with
scripts/kshell.sh
You will see the kataOS prompt showing up when you hit enter. Use ctrl-c to leave the console.
Renode has its own console to control the emulation environment. You can connect to it by
telnet localhost 1234
For example, you can check the core status
(matcha) cpu1 IsHalted False
or stop the whole emulation with
(matcha) quit
You can launch the ML workload execution by communicating through the debug console
KATA> test_mlexecute
and you should see
15:17:59.9864 [INFO] uart1: [output] KATA> test_mlexecute ... 15:18:02.6868 [INFO] cpu2: simprint: "main returned: ", 0 (0x0)
For more available Shodan build targets, please see Build target lists.