Recovery

Intro

The following documentation describes the process of recovering hardware from the brick state using an RTE and Dasharo open-source firmware.

External flashing

Prerequisites

• Prepared RTE
• 5x2 1mm pitch female header to 10x 2.54mm female DuPont connector adapter cable
• TPM removed

Connections

To prepare the stand for flashing follow the steps described in the Generic test stand setup.

Connect the RTE to the BIOS_PH1 header according to the following pinout:

The mentioned BIOS_PH1 header is not listed in the SPC741D8-2L2T user manual. It can be found next to the debug code seven segment display as marked on the image below.

Firmware flashing

To flash firmware follow the steps described below:

1. Login to RTE via ssh or minicom.
2. Turn on the platform by connecting the power supply.
3. Wait at least 5 seconds.
4. Turn off the platform by using the power button.
5. Wait at least 3 seconds.

6. Set the proper state of the SPI by using the following commands on RTE:

   # set SPI Vcc to 3.3V
   echo 1 > /sys/class/gpio/gpio405/value
   # SPI Vcc on
   echo 1 > /sys/class/gpio/gpio406/value
   # SPI lines ON
   echo 1 > /sys/class/gpio/gpio404/value
   

   Starting with RTE distro v0.8.x the GPIOS are 517, 518, 516.

7. Wait at least 2 seconds.

8. Disconnect the power supply from the platform.
9. Wait at least 2 seconds.

10. Check if the flash chip is connected properly

    flashrom -p linux_spi:dev=/dev/spidev1.0,spispeed=16000
    

11. Flash the platform by using the following command:

    flashrom -p linux_spi:dev=/dev/spidev1.0,spispeed=16000 \
        -w [path_to_binary] --ifd -i bios -N
    

12. Change back the state of the SPI by using the following commands:

    echo 0 > /sys/class/gpio/gpio404/value
    echo 0 > /sys/class/gpio/gpio405/value
    echo 0 > /sys/class/gpio/gpio406/value
    

    Starting with RTE distro v0.8.x the GPIOS are 516, 517, 518.

13. Turn on the platform by connecting the power supply.