• ASUS KCMA-D8 Motherboard

• Overview
• Specifications
• Drivers
• Manual

• Memory Configuration
• PCI Slot Speeds
• Jumpers

• When booting Ubuntu 18.10, there's a gfx error; type help and press Enter to boot ¹⁾
• Jumpers seem to act slightly different with Coreboot ²⁾
• Windows 10's installer can't start ³⁾
• For unknown reasons, some builds of Coreboot from master have unreliable POST; using the release tar of 4.9 works fine though, and as of 2019/04/20, is the latest known-good release

• Samsung M393B5270CH0-CH9 ⁴⁾
• SK Hynix HMT151R7BFR4C-H9 ^{5) 6)}

• Nanya NT2GC64B88B0NF-CG ⁷⁾
• Micron 16JTF25664AZ-1G4F1 ⁸⁾
• Samsung M378B5273CH0-CK0 ⁹⁾

• Fedora Workstation 29 cannot be used to compile older versions of Coreboot wanting a non-matching major GCC version for crossgcc ¹⁰⁾

sudo dnf install make ncurses-devel acpica-tools flex bison gcc-c++ patch zlib-devel gcc-gnat pciutils-devel

sudo zypper install git-core make cmake ncurses-devel acpica flex bison gcc-c++ patch zlib-devel gcc-ada pciutils-devel

cd ~ && mkdir -p ~/'Projects' && rm -Rf ~/'Projects/coreboot/src' && sync && git clone --branch 'master' --depth '1' --recurse-submodules 'https://review.coreboot.org/coreboot.git' ~/'Projects/coreboot/src' && sync

cd ~/'Projects/coreboot/src' && make 'crossgcc-clean' && make 'crossgcc-i386' CPUS='16'

• Use CMOS for configuration values speeds up boot significantly
• Including CPU microcode caused Linux to kernel panic on 2019/04/16
• For some unknown reason, POST randomly fails at times depending on when Coreboot is built, regardless of what config settings are used

• Last updated: 2019/05/22

• Mainboard vendor: ASUS
• Mainboard model: KCMA-D8
• ROM chip size: 2048 KB (2MB)
• System Power State after Failure: S5 Soft Off

• Local version string: Nightwane
• [*] Use CMOS for configuration values
• [*] Load default configuration values into CMOS on each boot
• [ ] Compress ramstage with LZMA
• [ ] Include the coreboot .config file into the ROM image
• [ ] Create a table of timestamps collected during boot

• Include CPU microcode in CBFS: Do not include microcode updates
• [*] Enable high speed SPI clock

• [ ] Serial port on SuperIO
• [ ] Support Intel PCI-e WiFi adapters

• [ ] Send console output to a CBMEM buffer
• Default console log level: 0: EMERG
• [*] Don't show any POST codes

• SeaBIOS version: master
• [*] Hardware init during option ROM execution
• SeaBIOS debug level (verbosity): 0

cd ~/'Projects/coreboot/src' && make 'distclean' && make 'nconfig' && sync

• Presents config options that are changed from defaults
• Reference
• Last updated: 2019/05/22

cd ~/'Projects/coreboot/src' && make 'savedefconfig' && gio open ~/'Projects/coreboot/src/defconfig'

CONFIG_LOCALVERSION="Nightwane"
CONFIG_USE_OPTION_TABLE=y
CONFIG_STATIC_OPTION_TABLE=y
# CONFIG_COMPRESS_RAMSTAGE is not set
# CONFIG_INCLUDE_CONFIG_FILE is not set
# CONFIG_COLLECT_TIMESTAMPS is not set
CONFIG_VENDOR_ASUS=y
CONFIG_BOARD_ASUS_KCMA_D8=y
# CONFIG_DRIVERS_UART_8250IO is not set
CONFIG_POWER_STATE_OFF_AFTER_FAILURE=y
# CONFIG_CONSOLE_CBMEM is not set
CONFIG_CPU_MICROCODE_CBFS_NONE=y
CONFIG_SOUTHBRIDGE_AMD_SB700_33MHZ_SPI=y
# CONFIG_DRIVERS_INTEL_WIFI is not set
CONFIG_DEFAULT_CONSOLE_LOGLEVEL_0=y
CONFIG_NO_POST=y
CONFIG_SEABIOS_MASTER=y
CONFIG_SEABIOS_THREAD_OPTIONROMS=y
CONFIG_SEABIOS_DEBUG_LEVEL=0

• Last updated: 2019/05/23

gio open ~/'Projects/coreboot/src/src/mainboard/asus/kcma-d8/cmos.default'

l3_cache_partitioning=Enable

experimental_memory_speed_boost=Enable

cd ~/'Projects/coreboot/src' && make clean && make && sync

mv ~/'Projects/coreboot/src/build/coreboot.rom' ~/'Downloads/KCMAD8-coreboot-'$(date +%Y-%m-%d)'.rom' && sync

• Add internal:amd_imc_force=yes after the --programmer flag if flashing from ASUS proprietary BIOS ^{11) 12) 13)}

sync && sudo flashrom --programmer 'internal' --write ~/'Downloads/KCMAD8-coreboot-'*'.rom'