Lenovo ThinkPad T440p

This page describes how to run coreboot on Lenovo ThinkPad T440p.

Required proprietary blobs

Please see mrc.bin.

Flashing instructions

T440p has two flash chips, an 8 MiB W25Q64FV and a 4 MiB W25Q32FV. To flash coreboot, you just need to remove the big door according to the T440 Hardware Maintenance Manual and flash the 4 MiB chip.

../../_images/t440p_flash_chip.jpgT440p flash chip

To access the 8 MiB chip, you need to remove the base cover.

../../_images/t440p_all_flash_chips.jpgT440p 8 MiB flash chip

The flash layout of the OEM firmware is as follows:

00000000:00000fff fd
00001000:00002fff gbe
00003000:004fffff me
00500000:00bfffff bios

After flashing coreboot, you may need to re-plug the AC adapter to make the laptop able to power on.

Known Issues

  • Cannot get the mainboard serial number from the mainboard: the OEM UEFI firmware gets the serial number from an “emulated EEPROM” via I/O port 0x1630/0x1634, but it’s still unknown how to make it work
  • The dGPU does not currently work in Windows.

Working

  • boot Arch Linux with Linux 4.19.77 from SeaBIOS payload
  • integrated graphics init with libgfxinit
  • EHCI debug: the port is the non-charging USB2 port on the right
  • video output: internal (eDP), miniDP, dock DP, dock HDMI
  • ACPI support
  • keyboard and trackpoint
  • SATA
  • M.2 SATA SSD
  • USB
  • Ethernet
  • WLAN
  • WWAN
  • bluetooth
  • virtualization: VT-x and VT-d
  • dock
  • CMOS options: wlan, trackpoint, fn_ctrl_swap
  • internal flashing when IFD is unlocked
  • using me_cleaner
  • dGPU (must be enabled in CMOS options)