Build the Coreboot ROM Image (ThinkPad X60-32bit) ================================================= Copyright (C) 2017, 2018, 2019, 2021, 2022 Kai Mertens Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled "GNU Free Documentation License". NOTE: This file lists essential steps for reference only, but should be thoroughly reviewed. Please use the toolchain scripts instead. See `../doc/toolchain.md`. Prepare ------- See Coreboot Build How-To: Basically: $ git clone https://review.coreboot.org/coreboot $ cd coreboot $ git checkout 4.8.1 $ git submodule update --init --checkout $ make crossgcc-i386 Configuration ------------- $ make menuconfig Use default values, but additionally select/deselect as specified: * Mainboard - Mainboard vendor (Lenovo) ---> - Mainboard model (ThinkPad X60 / X60s / X60t) ---> - ROM chip size (2048 KB (2 MB)) ---> - (0x200000) Size of CBFS filesystem in ROM * General Setup - [*] Use CMOS for configuration values * Chipset - Include CPU microcode in CBFS (Do not include microcode updates) ---> NOTE: We prefer to avoid CPU Microcode Updates on machines that are known to work well enough without (see libreboot’s documentation). Otherwise select "Generate from tree". * Devices - Graphics initialization (Use native graphics init) ---> - Display ---> + Framebuffer mode (Linear "high-resolution" framebuffer) ---> * Console - [ ] Serial port console output * Payload - Add a payload (An ELF executable payload) ---> - `"(payload.elf)"` Payload path and filename NOTE: File `payload.elf` should match your previously built executable GRUB payload file for platform i386-coreboot. See [GRUB How-To][]. - Secondary Payloads ---> + Select: Load coreinfo as a secondary payload + Select: Load nvramcui as a secondary payload NOTE: The `.config` file may contain your paths which you probably don't want to share with others. Compile ------- When you have exit the menuconfig tool, type: $ make This will provide the `coreboot.rom` in folder `build/`. Add Custom Files ---------------- ### Add Zerocat’s GRUB Configuration File Use coreboot’s `cbfstool` to add the custom configuration file as `etc/zerocat.cfg`: $ build/cbfstool build/coreboot.rom \ add -t raw -n etc/zerocat.cfg -f $ build/cbfstool build/coreboot.rom \ print See [grub@2.02_zerocat.cfg][] for reference. Before using it, please edit the file and adjust your keyboard layout which is currently pre-set via `keymap`. ### Secondary Payloads #### NVRAMCUI and Coreinfo Secondary payloads `nvramcui` and `coreinfo` should be accompanied with an informative message about occasional freezes, what can be achieved with GRUB, but not with SeaBIOS. Therefor, let’s move them out of the SeaBIOS `img/` search path: $ for i in coreinfo nvramcui; do \ build/cbfstool build/coreboot.rom \ extract -m x86 -n img/$i -f $i.extracted && \ build/cbfstool build/coreboot.rom \ remove -n img/$i && \ build/cbfstool build/coreboot.rom \ add-payload -c lzma -n $i -f $i.extracted && \ rm $i.extracted; \ done; NOTE: When invoking `coreinfo` fromout the GRUB Boot Menu, please get prepared for occasional freezes due to CPU exceptions and faults. See [Coreinfo CPU Exceptions][]. NOTE: When invoking `nvramcui` fromout the GRUB Boot Menu, switch your RF Kill Switch off! Active bluetooth devices might freeze the application. NOTE: Hmm..., and secondary payloads `nvramcui` and `coreinfo` seem to freeze in case a fingerprint sensor is part of the system, so please unplug that sensor. #### Add SeaBIOS Payload [Zerocat’s GRUB Configuration File][grub@2.02_zerocat.cfg] already comes with a menu entry to chainload the SeaBIOS payload. Add files to the `coreboot.rom` as required: $ build/cbfstool build/coreboot.rom \ add -t raw -n config-seabios -f $ build/cbfstool build/coreboot.rom \ add -t raw -n vgaroms/vgabios.bin -f $ build/cbfstool build/coreboot.rom \ add-payload -n seabios.elf -f $ build/cbfstool build/coreboot.rom \ print Please read section “Adding SeaBIOS Payload” of the [GRUB How-To][] for more information. ### Add Background Images [Zerocat’s GRUB Configuration File][grub@2.02_zerocat.cfg] has already been prepared to make use of background images, if available. Just add a first image like so: $ build/cbfstool build/coreboot.rom \ add -t raw -n background.png -f $ build/cbfstool build/coreboot.rom \ print You may add up to three more images named `background_1.png`, `background_2.png` and `background_3.png`. This feature provides space for additional information, such as a documented flash procedure for example. Use hotkey 'i' in GRUB’s Boot Menu to cycle through the images. Tweak Parameters in `cmos.default` ---------------------------------- Tweak parameters `gfx_uma_size`, `wwan` and `bluetooth` in the ROM’s `cmos.default` file: $ build/util/nvramtool/nvramtool -C build/coreboot.rom -w gfx_uma_size=64M $ build/util/nvramtool/nvramtool -C build/coreboot.rom -w wwan=Disable $ build/util/nvramtool/nvramtool -C build/coreboot.rom -w bluetooth=Disable Inquire parameter’s possible values with option `-e`, i.e.: $ build/util/nvramtool/nvramtool -C build/coreboot.rom -e gfx_uma_size Our “standard” CMOS setup now looks like this: $ build/util/nvramtool/nvramtool -C build/coreboot.rom -a boot_option = Fallback reboot_counter = 0x0 debug_level = Spew nmi = Enable gfx_uma_size = 64M boot_devices = '' boot_default = 0x40 cmos_defaults_loaded = Yes lpt = Enable hyper_threading = Enable first_battery = Primary bluetooth = Disable wwan = Disable wlan = Enable trackpoint = Enable sticky_fn = Disable power_management_beeps = Enable low_battery_beep = Enable volume = 0x3 tft_brightness = 0xff NOTE: You will be able to modify these settings with the NVRAMCUI Payload upon boot time. Done! ----- Your ROM should now be ready to go! In order to reset old & obsolete CMOS settings, please remind to unplug the coin battery for some seconds after flashing. [GRUB How-To]: ../doc/grub-how-to.md [Coreinfo CPU Exceptions]: ../doc/coreinfo-cpu-exceptions.md [grub@2.02_zerocat.cfg]: ../templates/grub@2.02_zerocat.cfg