Dasharo internal flashing (Ubuntu 20.04)

Intro

Flashing Dasharo can be done from Linux using flashrom with the internal programmer. This document describes the process of building, installing and running flashrom on Ubuntu 20.04.

Pre-setup

Ensure that the EC is running updated firmware. Follow the steps outlined in EC firmware update

Build flashrom

Currently, the latest flashrom release lacks support for Tiger Lake-U internal flashing. Because of this, we need to build flashrom from source.

Install build dependencies:

apt install git build-essential debhelper pkg-config libpci-dev libusb-1.0-0-dev libftdi1-dev meson

Obtain source code:

git clone https://review.coreboot.org/flashrom.git
cd flashrom

Build flashrom:

make
sudo make install

Reading flash contents

To read from the flash and save them to a file (dump.rom), execute the following command:

flashrom -p internal -r dump.rom

Flashing Dasharo

To flash Dasharo to the laptop, execute the following command - replace [path] with the path to the Dasharo image you want to flash, e.g. build/coreboot.rom.

If stock firmware or Dasharo version below v1.1.0 is currently installed:

flashrom -p internal -w [path] --ifd -i bios

If version v1.1.0 or higher is currently installed, only the RW_SECTION_A partition of the flash needs to be updated. Flash it using the following command:

flashrom -p internal -w [path] --fmap -i RW_SECTION_A

This command also preserves the bootsplash, UEFI settings and the boot order.