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Factory Build and Test

This is a recommended process for building and testing Modalix-based boards in a factory. Adapt it to your board, test fixtures, and assembly line.

  1. Physical Assembly
  2. Electrical Verification
  3. Program the Board ID and MAC Address
  4. Set Up the Test Station
  5. Boot the Test Image
  6. Run Diagnostics
  7. Program the Production Image
  8. Application Testing, Labeling, and Packaging

Serial Consoles​

A Modalix board has two serial consoles. Both run at 115200 baud with hardware flow control disabled.

ConsoleUsed for
tRoot UART (secure boot)Board ID and MAC programming, tRoot update messages
U-Boot/Linux UARTU-Boot commands, Linux login, and every test in this page

The connector for each depends on the board. On the reference carrier board, see the UART roles in Carrier Board Bring-up. Connect to each console from the host, for example:

sima-user@sima-user-machine:~$ minicom -b 115200 -D /dev/ttyUSB0

The device name (/dev/ttyUSB0, /dev/ttyUSB1) depends on how the cables enumerate on the host.

Physical Assembly​

This depends on your board and production flow: fitting heatsinks, installing the board in an enclosure or test fixture, and so on.

Electrical Verification​

  1. List the access points for every main power rail, and check each rail's impedance for opens and shorts.
  2. List the voltages you can measure, and log them for every board, or for a sample of boards in each build.
  3. Check the clocks you can measure, and record them against each serial number.

Program the Board ID and MAC Address​

The board ID (also called the device ID) and the MAC addresses are written to the MLSoC's one-time programmable (OTP) memory by a special tRoot firmware.

OTP values are permanent

OTP memory can be written only once. Check each value before you confirm it.

  1. Connect the host to the tRoot UART.

  2. Connect the SPI flash programmer, then connect power.

  3. Load the OTP programming tRoot firmware into SPI flash, as described in Program the tRoot SPI Flash.

  4. Remove power, disconnect the SPI flash programmer, and reconnect power.

  5. On the tRoot console, enter the board ID in hex, confirm it, then enter the MAC address:

    enter hwid in hex format(ex:0x00010012)
    hwid entered is 0x123
    Press (Y/N)
    burning hwid
    Configured HWID :: 0x123
    Activated ID Selector :: 1
    Enter mac addr in format (A0:B1:C2:D3:E4:F5)

    After you enter the MAC address, the board immediately completes a boot sequence.

  6. Power-cycle the board, and check that it boots and reports that the board ID is already programmed.

  7. Load your production tRoot firmware into SPI flash, as described in Program the tRoot SPI Flash.

Program the tRoot SPI Flash​

The tRoot firmware is a single binary, troot_blob.be. You write one of two versions: the OTP programming firmware used above, or your production firmware. SiMa.ai recommends a Total Phase Aardvark I2C/SPI host adapter with the Total Phase Flash Center software.

  1. Install Flash Center on the host.
  2. Connect the programmer to the board's SPI flash header. This connector depends on the board, and is typically a dual-row header.
  3. Start Flash Center. It also has command-line tools if you want to automate this step.
  4. Add the adapter.
  5. Select the target device: choose SPI Flash, then the part fitted to your board, for example a Winbond W25Q16 (2 MB).
  6. Load troot_blob.be.
  7. Program the flash.

Set Up the Test Station​

  1. If the board under test needs a carrier or interface board, connect it.
  2. Connect the host to both the tRoot UART and the U-Boot/Linux UART.
  3. If the board has Ethernet ports, connect each one to the host.
  4. If the board has MIPI camera inputs, connect test cameras.
  5. If the board is a PCIe card, install it in a host PCIe Gen5 slot of at least x8 width.

Boot the Test Image​

Boot the latest released test firmware from an SD card or the network, as described in Flash an Image to eMMC. An SD card is preferred, because it leaves the Ethernet ports free for the network stress test.

Run Diagnostics​

The sequence is: record the idle temperature, run the stress tests, check the final temperature, then check each I/O interface.

Run every test in the U-Boot/Linux console. Power on the board, wait for the Linux prompt, log in as sima with password edgeai, then become root:

sima@modalix:~$ sudo su

If the board has Ethernet, give the host one address per board port. For example, with the host interface eno1:

sima-user@sima-user-machine:~$ sudo ifconfig eno1:1 192.168.1.10 up
sima-user@sima-user-machine:~$ sudo ifconfig eno1:2 192.168.2.10 up
sima-user@sima-user-machine:~$ sudo ifconfig eno1:3 192.168.3.10 up
sima-user@sima-user-machine:~$ sudo ifconfig eno1:4 192.168.4.10 up

For a PCIe card, remove any external power from the card before you power on the host. The card is powered from the slot.

1. Idle Temperature​

Find the hwmon device named simaai_modalix_thermal_sensor:

root@modalix:~# grep -l simaai_modalix_thermal_sensor /sys/class/hwmon/hwmon*/name

Read its temp1_input ten times and average the readings. The value is in thousandths of a degree Celsius. Replace X with the number you found:

root@modalix:~# for i in $(seq 10); do cat /sys/class/hwmon/hwmonX/temp1_input; done | awk '{s+=$1} END {print s/NR/1000 " C"}'

2. Ethernet​

Start an iperf3 server on the host:

sima-user@sima-user-machine:~$ iperf3 -s

On the board, run a client for each Ethernet port:

root@modalix:~# iperf3 -c 192.168.1.10 -t 60 --logfile /tmp/iperf1   # end0
root@modalix:~# iperf3 -c 192.168.2.10 -t 60 --logfile /tmp/iperf2   # end1
root@modalix:~# iperf3 -c 192.168.3.10 -t 60 --logfile /tmp/iperf3   # end2
root@modalix:~# iperf3 -c 192.168.4.10 -t 60 --logfile /tmp/iperf4   # end3

3. Memory​

root@modalix:~# stress-ng --class memory --all -1 --log-file /tmp/memorytest --log-brief --verify --abort -x atomic,heapsort,judy,mergesort,radixsort,tree,wcs,zlib -t 370s

4. CPU Cache​

root@modalix:~# stress-ng --class cpu-cache --seq 2 -t 8s --log-brief --log-file /tmp/cpucache

5. CPU​

root@modalix:~# stress-ng --cpu 0 --verify -t 1m --log-brief --log-file /tmp/cpu0

--cpu 0 runs on every CPU. The result must report 16 CPUs.

6. Final Temperature​

Read the temperature again as in Idle Temperature, and check it against your board's thermal limits.

7. PCIe Loopback​

  1. On the host, install sima_pcie_hostpkg.sh, then boot the board with the matching binaries.

  2. After the board boots, run this in the board console:

    root@modalix:~# sima_pep_test

  3. On the host, create a 1 MB test file and start the loopback test:

    sima-user@sima-user-machine:~$ dd if=/dev/urandom of=~/data1MB.bin bs=1M count=1
    sima-user@sima-user-machine:~$ sima_mla_test -Q 1 -q 0 -e 32 -i 8 -d ~/data1MB.bin

The host prints a success message with the transmitted and received frame counts.

8. MIPI Cameras​

  1. Load the camera overlays for the ports under test. Reboot, interrupt autoboot, and set dtbos. Overlay names have the form modalix-som-<carrier>-<camera>-<port>.dtbo. For an Arducam IMX477 on the first camera port of a Modalix DevKit:

    sima$ env set dtbos modalix-som-waveshare-ARDU-IMX477-1CAM.dtbo
    sima$ saveenv

    Overlays are specific to the camera, the port, and the board. See MIPI Camera Interfaces.

  2. Connect an IMX477 camera to each port under test, power-cycle, log in, and run sudo su.

  3. Capture raw frames, then start the ISP output. Change video0raw and video0out to match the port under test:

    root@modalix:~# gst-launch-1.0 v4l2src device=/dev/video0raw ! 'video/x-bayer,format=rggb12le,width=2048,height=1080,framerate=30/1' ! queue ! multifilesink location=/tmp/mipi_in_%d.raw12 &
    root@modalix:~# gst-launch-1.0 v4l2src device=/dev/video0out ! 'video/x-raw,format=RGB,width=2048,height=1080,framerate=30/1' ! fakesink

    The first pipeline writes 30 files a second into /tmp, which has limited space. Stop after about 10 seconds: press Ctrl+C to stop the second pipeline, then run fg and press Ctrl+C to stop the first.

9. SD Card​

Skip this test if the board booted from the SD card. Otherwise, insert an SD card and run the storage test script. Choose 1 for the SD card, then 2 for a quick throughput test or 3 for a full read and write of the card:

root@modalix:~# /usr/bin/simaai_pt/emmc_sd_test.sh
Enter 0 - /dev/mmcblk0 (eMMC) or 1 /dev/mmcblk1 (SD card)
Choice: 1
1) Test 1: Memory Operations
2) Test 2: Throughput Measurement
3) Test 3: Whole memory read and write
4) Test 4: sd_card insertion and connection back
Enter your choice (1 or 2 or 3 or 4): 2
Throughput: 11.3099 MB/s

10. eMMC​

warning

This test overwrites the eMMC. Run it only when the board is booted from the network or an SD card, and flash the production image afterwards.

Run the same script and choose 0 for the eMMC, then 2 or 3.

11. Display and USB​

If the board has a display output, boot an eLxr image from the network or an SD card. Connect a USB keyboard and mouse, and check that the desktop appears at 1920×1080. Log in with the keyboard and mouse, using the same credentials as the console.

12. NVMe​

With an NVMe drive fitted, check that it is detected, then measure the direct read speed:

root@modalix:~# nvme list
root@modalix:~# hdparm -tT --direct /dev/nvme0n1

To format and mount the drive, see Configure NVMe Storage.

13. tRoot Self-Update​

This test installs a tRoot update package with swupdate.

  1. Copy the production troot-upgrade-simaai-ev.swu to /tmp on the board.

  2. Keep both the tRoot and U-Boot/Linux consoles connected.

  3. In the U-Boot/Linux console, as root:

    root@modalix:~# swupdate -v -H simaai-image-troot:1.0 -i /tmp/troot-upgrade-simaai-ev.swu

  4. Check that output on the tRoot console stops within 5 minutes.

Program the Production Image​

Write the latest released production image to the eMMC, as described in Flash an Image to eMMC, then check that the board boots from eMMC.

Application Testing, Labeling, and Packaging​

These steps depend on your product.