Building Host Programs

Because we would like to have both Zigbee and Openthread capabilities, we will need to build 2 different host services :

• OTBR Agent
• Z3 Gateway CPC

However, to ensure interoperability, we need to align all different software versions.

Because CPC daemon is at the center of this architecture, we will align all our sw pieces around it.

CPCd version numbering aligns with Silicon Labs Gecko SDK version. OTBR sources used in this guide will come from GSDK

Eventually, since we are interested in running Matter, we will need to align version numbering with it too

Identifying Matter/OpenThread related software commit hashes

• Start from CPC, which latest version is available on its release page

  • In this case we are running v4.5.1
  • This can also be retrived on an deployed environment using cpcd -v

• From there we need to look at the GSDK release page that matches v4.5.1 and look for the OpenThread Release note of that release

  • Section 8.2 provides : OpenThread GitHub repo (https://github.com/openthread/openthread) up to and including commit 1fceb225b
  • Section 8.3 provides : OpenThread border router GitHub repo (https://github.com/openthread/ot-br-posix) up to and including commit e56c02006

• Finally, if we want to use Matter over this router, we need to go to Silicon Labs' matter_extension repository release page and look for the one that uses the same Simplicity SDK v2024.6.1 as we are, this appears to be Matter Extension v2.3.1-1.3

  • Version listing provides : Simpicity SDK v2024.6.1

  • Version listing provides : OpenThread: v2.5.1.0

    hash 1fceb225b

  • Version listing provides : Matter hash 5bb5c9e

At this point we are sure that Gecko SDK and OpenThread versions and hashes align . We also know which Matter and OTBR hash we will be using

In summary for developments with RCP from Simplicity Studio on Simplicity SDK 2024.6.1 will require following hashes :

CPC Daemon (CPCd)

Gecko SDK Suite (GSDK)

If chiptool build is required :

Connectivity Standards Alliance (CSA) connectedhomeip (Matter)

Silicon Labs fork of Connectivity Standards Alliance (CSA) connectedhomeip (Matter) used in Simplicity Studio

This does not allow build of chip-tool (Use CSA main repo) This does not allow builds outside of Simplicity Studio

If required, everything can be built from sources using below each repo hash (Not covered in this guide, where we cover only building from GSDK) :

OpenThread for RCP build

OpenThread Border Router (OTBR)

Downloading and Building OTBR Agent

Downloading OTBR sources

Since we are using CPC, we will fully rely on OTBR sources provided via Silicon Labs GSDK

We go back to our working directory :

cd ~/border_router_dev

And clone Gecko SDK version 2024.6.1 :

git clone https://github.com/SiliconLabs/simplicity_sdk.git
cd simplicity_sdk
git checkout v2024.6.1

Building OTBR Agent

Building OTBR Agent requires a lot of extra steps from GSDK.

1. First we need to symlink the OpenThread repo from GSDK to the ot-br-posix third party repo :

   ln -s ~/border_router_dev/simplicity_sdk/util/third_party/openthread/ ~/border_router_dev/simplicity_sdk/util/third_party/ot-br-posix/third_party/openthread/repo 
   

2. Copy the Silicon Labs specific platform header to the ot-br-posix folder

   cp ~/border_router_dev/simplicity_sdk/protocol/openthread/platform-abstraction/posix/openthread-core-silabs-posix-config.h ~/border_router_dev/simplicity_sdk/util/third_party/openthread/src/posix/platform/
   

3. Set the GSDK absolute path as an environment variable

   export GSDK_DIR=~/border_router_dev/simplicity_sdk
   

4. Set the CPCd source directory path as an environment variable

   export CPCD_DIR=~/border_router_dev/cpc-daemon
   

At this stage we are ready to launch the OTBR Agent build command with CPC support. For detailed documentation about the build options refer to section 2.2.3.2 of AN1333

Go into the ot-br-posix folder :

cd ~/border_router_dev/simplicity_sdk/util/third_party/ot-br-posix/

To launch the build procedure run :

sudo RELEASE=1 REFERENCE_DEVICE=1 BACKBONE_ROUTER=1 NAT64=1 DNS64=1 ./script/bootstrap

This will install all dependencies required to build the agent and can take a while

Followed by :

sudo INFRA_IF_NAME=eth0 RELEASE=1 REFERENCE_DEVICE=1 BACKBONE_ROUTER=1 BORDER_ROUTING=1 NAT64=1 DNS64=1 OTBR_OPTIONS="-DOT_THREAD_VERSION=1.4 -DOT_MULTIPAN_RCP=ON -DCPCD_SOURCE_DIR=$CPCD_DIR -DOT_POSIX_RCP_VENDOR_BUS=ON -DOT_POSIX_CONFIG_RCP_VENDOR_DEPS_PACKAGE=$GSDK_DIR/protocol/openthread/platform-abstraction/posix/posix_vendor_rcp.cmake -DOT_POSIX_CONFIG_RCP_VENDOR_INTERFACE=$GSDK_DIR/protocol/openthread/platform-abstraction/posix/cpc_interface.cpp -DOT_CLI_VENDOR_EXTENSION=$GSDK_DIR/protocol/openthread/platform-abstraction/posix/posix_vendor_cli.cmake -DOT_PLATFORM_CONFIG=openthread-core-silabs-posix-config.h -DOTBR_DUA_ROUTING=ON -DOTBR_DNSSD_DISCOVERY_PROXY=ON -DOTBR_SRP_ADVERTISING_PROXY=ON" ./script/setup

Building Zigbee 3.0 CPC Host

Generating Project using Simplicity Studio

Simplcity studio is required to generate the Zigbee Host software required to address the NCP CMP firmware. If you followed this guide in its entirety, you should already the have the IDE up and running

First step will be to Download the Gecko SDK that matches the versioning we chose above at CPCd stage. In our case we will fetch GSDK v4.4.0

To do so, simply click the Install button and click on Manage Installed Packages :

Once in the package manager, got to the SDK tab and click Add SDK

When done, go back the Launcher perspective of the IDE (Main Menu) and do precisely as follows :

1. Locate the My Products view and type linux in the textbox
2. Click Linux 64 bit and/or Linux 32 bit depending on the architecture you run your hosts
3. You should now have a Linux 64 Bit listed in the products view
4. Click Linux 64 Bit listed in the products view, this should rearrange the Launcher so you can create a project for Linux archs on GSDK 4.4.0

5. Click Create New Project in the main view

   

6. In the examples list, look for Zigbee - Gateway CPC and click Next

7. In the With project files: select Copy contents and then click Finish

   

At this point we have a default CPC Host project that we can either cross compile locally or push on our Gateway and build there.

We will go for the second option

Note : If you do not follow these steps exactly as described, you might not be able to generate a project for Linux Hosts using the Wizard and/or build it later on

Copying the Zigbee Gateway sources to the Raspberry Pi

Linux/Mac users can simply use scp to copy the entire Z3GatewayCpc folder and its contents to our border router working directory

Windows users can use WinSCP

Back on the Raspberry, cd to the Zigbee project folder we just copied:

cd ~/border_router_dev/Z3GatewayCpc/

Building the Zigbee Gateway sources on the Raspberry Pi

Silicon Labs Host projects are Makefile based, simply call make by specifying the makefile provided in the project directory as below :

make -f Z3GatewayCpc.Makefile -j2

The resulting executable file will be located under build/debug/Z3GatewayCpc