Supermicro X10SLM+-F

This section details how to run coreboot on the Supermicro X10SLM+-F.

Required proprietary blobs

Please see mrc.bin.

Building coreboot

If you haven’t already, build the coreboot toolchain as described in coreboot Lesson 1: Starting from scratch.

A fully working image should be possible so long as you have the Haswell mrc.bin file. You can set the basic config with the following commands. However, it is strongly advised to use make menuconfig afterwards (or instead), so that you can see all of the settings.

make distclean # Note: this will remove your current config, if it exists.
touch .config
./util/scripts/config --enable VENDOR_SUPERMICRO
./util/scripts/config --enable BOARD_SUPERMICRO_X10SLM_PLUS_F
./util/scripts/config --enable HAVE_MRC
make olddefconfig

If you don’t plan on using coreboot’s serial console to collect logs, you might want to disable it at this point (./util/scripts/config --disable CONSOLE_SERIAL). It should reduce the boot time by several seconds. However, a more flexible method is to change the console log level from within an OS using util/nvramtool, or with the nvramcui payload.

Now, run make to build the coreboot image.

Flashing coreboot

In addition to the information here, please see the Flashing firmware tutorial.

Internal programming

Under the vendor firmware, the BIOS region of the flash chip is write-protected. Additionally, the vendor flashing tool does not work with a coreboot image. So, external programming needs to be used when first installing coreboot. By default, coreboot is not configured to write-protect the BIOS region, so internal programming can be used thereafter.

flashrom may be used to flash coreboot internally:

sudo flashrom -p internal --ifd -i bios --noverify-all -w coreboot.rom

The use of --noverify-all is required since the Management Engine region is not readable even by the host.

External programming

The main firmware flash chip is an SOIC-8 package located near the CMOS battery and SATA ports. It should come with a sticker attached that states the firmware revision (e.g. “X10SLH 4.424”). The chip model is an N25Q128A, and the datasheet can be found here.

As with internal programming, flashrom works reliably:

flashrom -p <your-programmer> --ifd -i bios -w coreboot.rom

For flashing to work, power to the board should be disconnected (ACPI G3), and power should be supplied from the external programmer. There is a diode attached to Vcc, so such flashing should not damage the board. During testing, a single X10SLM+-F has been flashed dozens of times this way without issue.

BMC (IPMI)

This board has an ASPEED AST2400, which has BMC functionality. The BMC firmware resides in a 32 MiB SOIC-16 chip just above the AST2400. This chip is an MX25L25635F, whose datasheet can be found here.

Removing the BMC functionality

The BMC functionality on this board can be removed. If you do not need its features, removing the BMC functionality might increase security. This topic has not been widely explored, and you should only undertake this process at your own risk.

There is a jumper labelled JPB1 on the board that states the ability to disable the BMC. Though, pins 1 and 2 are fixed together, keeping the BMC enabled. It might be possible to disable the BMC by cutting the connection between pins 1 and 2 (and then connecting pins 2 and 3). This has not been tested so far.

Another approach is to erase the entire BMC firmware chip. However, if this is done, and the board’s power cycled, the voltage changes on some pins of the flash chip, so it will be harder to flash it again!

To remove the firmware, connect an external programmer to the BMC firmware chip. Vcc should not be connected via the external programmer. The system should be turned off, but the power still connected (ACPI S5). Then, erase the chip with flashrom. Power cycle the board, and the BMC should no longer be active.

If you erase the BMC firmware while using the vendor BIOS, you will need to cut the connection between pins 1 and 2 of JPB1. The system will stall for two minutes each time when booting, but it will eventually start. There is no such delay when running coreboot.

ECC DRAM

ECC DRAM seems to work, but please see mrc.bin for caveats.

Known issues

  • Broadwell CPUs are not supported. They might work with minimal changes to the code, but this has not been tested.
  • The PCH thermal sensor doesn’t yet have a driver in coreboot, so it can’t be used for temperature readings.
  • There is no automatic, OS-independent fan control. This is because the super I/O hardware monitor can only obtain valid CPU temperature readings from the PECI agent, but the required driver doesn’t exist in coreboot. The coretemp driver can still be used for accurate CPU temperature readings from an OS, and hence the OS can do fan control.

Please also see Known issues with Haswell.

Untested

  • TPM
  • PCIe (likely to work, but maybe not at Gen 3 speeds)
  • BMC (IPMI) functionality
  • internal serial port
  • chassis intrusion header
  • SATA DOM header
  • standby power header
  • serial GPIO headers
  • power supply SMBus header
  • jumpers not otherwise mentioned
  • LEDs

Working

  • USB
  • S3 suspend/resume
  • Gigabit Ethernet
  • SATA
  • external serial port
  • VGA graphics
  • disabling VGA graphics using the jumper
  • hiding the AST2400 using the CMOS setting
  • super I/O hardware monitor (see Known issues)
  • initialisation with Haswell MRC version 1.6.1 build 2
  • flashrom under coreboot
  • Wake-on-LAN
  • front panel header
  • internal buzzer

Technology

CPU Intel Haswell documentation
PCH Intel Lynx Point (C224)
Super I/O Nuvoton NCT6776
Coprocessor Intel SPS (server version of the ME)
Coprocessor ASPEED AST2400