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+coreboot lesson 1 - Starting from scratch
+=========================================
+
+From a fresh Ubuntu 16.04 or 18.04 install, here are all the steps required for
+a very basic build:
+
+Download, configure, and build coreboot
+---------------------------------------
+
+### Step 1 - Install tools and libraries needed for coreboot
+ $ sudo apt-get install -y bison build-essential curl flex git gnat-5 libncurses5-dev m4 zlib1g-dev
+
+### Step 2 - Download coreboot source tree
+ $ git clone https://review.coreboot.org/coreboot
+ $ cd coreboot
+
+### Step 3 - Build the coreboot toolchain
+Please note that this can take a significant amount of time
+
+ $ make crossgcc-i386 CPUS=$(nproc)
+
+Also note that you can possibly use your system toolchain, but the results are
+not reproducible, and may have issues, so this is not recommended. See step 5
+to use your system toolchain.
+
+### Step 4 - Build the payload - coreinfo
+ $ make -C payloads/coreinfo olddefconfig
+ $ make -C payloads/coreinfo
+
+### Step 5 - Configure the build
+
+* ##### Configure your mainboard
+ $ make menuconfig
+ select 'Mainboard' menu
+ Beside 'Mainboard vendor' should be '(Emulation)'
+ Beside 'Mainboard model' should be 'QEMU x86 i440fx/piix4'
+ select < Exit >
+These should be the default selections, so if anything else was set, run
+`make distclean` to remove your old config file and start over.
+
+* ##### Optionally use your system toolchain (Again, not recommended)
+ select 'General Setup' menu
+ select 'Allow building with any toolchain'
+ select < Exit >
+
+* ##### Select the payload
+ select 'Payload' menu
+ select 'Add a Payload'
+ choose 'An Elf executable payload'
+ select 'Payload path and filename'
+ enter 'payloads/coreinfo/build/coreinfo.elf'
+ select < Exit >
+ select < Exit >
+ select < Yes >
+
+##### check your configuration (optional step):
+
+ $ make savedefconfig
+ $ cat defconfig
+
+There should only be two lines (or 3 if you're using the system toolchain):
+
+ CONFIG_PAYLOAD_ELF=y
+ CONFIG_PAYLOAD_FILE="payloads/coreinfo/build/coreinfo.elf"
+
+### Step 6 - build coreboot
+ $ make
+
+At the end of the build, you should see:
+
+ Build emulation/qemu-i440fx (QEMU x86 i440fx/piix4)
+
+This means your build was successful. The output from the build is in the build
+directory. build/coreboot.rom is the full rom file.
+
+Test the image using QEMU
+-------------------------
+
+### Step 7 - Install QEMU
+ $ sudo apt-get install -y qemu
+
+### Step 8 - Run QEMU
+Start QEMU, and point it to the ROM you just built:
+
+ $ qemu-system-x86_64 -bios build/coreboot.rom -serial stdio
+
+You should see the serial output of coreboot in the original console window, and
+a new window will appear running the coreinfo payload.
+
+Summary
+-------
+
+### Step 1 summary - Install tools and libraries needed for coreboot
+You installed the minimum additional requirements for ubuntu to download and
+build coreboot. Ubuntu already has most of the other tools that would be
+required installed by default.
+
+* `build-essential` is the basic tools for doing builds. It comes pre-installed
+on some Ubuntu flavors, and not on others.
+* `git` is needed to download coreboot from the coreboot git repository.
+* `libncurses5-dev` is needed to build the menu for 'make menuconfig'
+* `m4, bison, curl, flex, gnat-5, zlib1g-dev` are needed to build the coreboot
+toolchain.
+
+If you started with a different distribution, you might need to install many
+other items which vary by distribution.
+
+### Step 2 summary - Download coreboot source tree
+This will download a 'read-only' copy of the coreboot tree. This just means
+that if you made changes to the coreboot tree, you couldn't immediately
+contribute them back to the community. To pull a copy of coreboot that would
+allow you to contribute back, you would first need to sign up for an account on
+gerrit.
+
+### Step 3 summary - Build the coreboot toolchain.
+This builds one of the coreboot cross-compiler toolchains for X86 platforms.
+Because of the variability of compilers and the other required tools between
+the various operating systems that coreboot can be built on, coreboot supplies
+and uses its own cross-compiler toolchain to build the binaries that end up as
+part of the coreboot ROM. The toolchain provided by the operating system (the
+'host toolchain') is used to build various tools that will run on the local
+system during the build process.
+
+### Step 4 summary - Build the payload
+To actually do anything useful with coreboot, you need to build a payload to
+include in the rom. The idea behind coreboot is that it does the minimum amount
+possible before passing control of the machine to a payload. There are various
+payloads such as grub or SeaBIOS that are typically used to boot the operating
+system. Instead, we used coreinfo, a small demonstration payload that allows the
+user to look at various things such as memory and the contents of coreboot's
+cbfs - the pieces that make up the coreboot rom.
+
+### Step 5 summary - Configure the build
+This step configures coreboot's build options using the menuconfig interface to
+Kconfig. Kconfig is the same configuration program used by the linux kernel. It
+allows you to enable, disable, and change various values to control the coreboot
+build process, including which mainboard(motherboard) to use, which toolchain to
+use, and how the runtime debug console should be presented and saved.
+Anytime you change mainboards in Kconfig, you should always run `make distclean`
+before running `make menuconfig`. Due to the way that Kconfig works, values will
+be kept from the previous mainboard if you skip the clean step. This leads to a
+hybrid configuration which may or may not work as expected.
+
+### Step 6 summary - Build coreboot
+You may notice that a number of other pieces are downloaded at the beginning of
+the build process. These are the git submodules used in various coreboot builds.
+By default, the BLOBS submodule is not downloaded. This git submodule may be
+required for other builds for microcode or other binaries. To enable downloading
+this submodule, select the option "Allow use of binary-only repository" in the
+"General Setup" menu of Kconfig
+This attempts to build the coreboot rom. The rom file itself ends up in the
+build directory as 'coreboot.rom'. At the end of the build process, the build
+displayed the contents of the rom file.
+
+### Step 7 summary - Install QEMU
+QEMU is a processor emulator which we can use to show coreboot
+
+### Step 8 summary - Run QEMU
+Here's the command line broken down:
+* `qemu-system-x86_64`
+This starts the QEMU emulator with the i440FX host PCI bridge and PIIX3 PCI to
+ISA bridge.
+* `-bios build/coreboot.rom`
+Use the bios rom image that we just built. If this is left off, the standard
+SeaBIOS image that comes with QEMU is used.
+* `-serial stdio`
+Send the serial output to the console. This allows you to view the coreboot
+debug output.