Board:lenovo/x220

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Revision as of 21:03, 6 January 2015 by Phcoder (talk | contribs) (→‎Status)
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The wiki is being retired!

Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to https://doc.coreboot.org/. Contributions welcome!

Status

Thanks for your interest in Lenovo X220 port. Issues:

  • no MRC cache (longer boot time)
  • yellow USB port isn't powered in power-off state.
  • Badly seated RAM may prevent booting (not really a problem but coreboot is more suspicious to this than vendor BIOS)

Tested (and works):

  • RAM module combinations of 4G+0, 4G+4G
  • S3 (Suspend to RAM)
  • digitizer on x220t variant
  • WLAN (first minipcie slot)
  • Linux (through GRUB-as-payload)
  • trackpoint
  • Fn hotkeys
  • Video (both internal and VGA, including native gfx init)
  • touchpad
  • battery indicator
  • Fingerprint reader.
  • Thermal management
  • Webcam
  • Expresscard slot (including hotplugging)
  • USB (all 3 ports)
  • bluetooth
  • SD card slot
  • LAN
  • Sound (integrated speakers, integrated mic, external headphones, external mic)
  • WWAN
  • WLAN slot USB
  • Windows (through SeaBIOS; you have to use extracted VGA blob, dumped from memory isn't good enough)
  • msata
  • displayport

Not tested:

  • Thinklight (probably works).
  • dock (probably works)
  • USB 3.0 in some models (probably doesn't work)

proprietary components status

  • CPU Microcode
  • VGA option rom (optional): you need it if you wantgraphics in SeaBIOS but most payloads should work without it (text mode or corebootfb mode)
  • ME(Management Engine) => you do not have to touch it(just leave it where it is)
  • EC(Embedded Controller) => you do not have to touch it(just leave it where it is)

Flashing

X220 has 1 flash chip of 8M. It's subdivided in roughly in 3 parts:

  • Descriptor (12K)
  • ME firmware (5M-12K)
  • System flash (7M)

ME firmware is not readable. Vendor firmware locks the flash and so you need to flash externally (unless until someone figures out a way around it).

Proceeds as follows:

  • Turn off your laptop, remove battery and AC adapter.
  • Remove the keyboard.
  • Connect your external SPI flasher to the top SPI chip which is under palm resting space, on left side of the board. It's a 8M chip.

I recommend using SOIC clip. Depending on the flasher you use, you may have to use separate 3.3V source. Make sure not to feed more than 3.3V ot the chip. I used buspirate as flasher and 3.3V power lines from another computer.

  • Read the flash. Twice. Compare the files to be sure. Save a copy of it on

external media.

flashrom -p <yourprogrammer> -r flash.bin
flashrom -p <yourprogrammer> -r flash2.bin
diff flash.bin flash2.bin

If they don't match, do not proceed.

  • Recover descriptor and me firmare:
 dd if=flash.bin of=coreboot/3rdparty/mainboard/lenovo/x220/descriptor.bin \
   count=12288 bs=1M iflag=count_bytes
 dd if=flash.bin of=coreboot/3rdparty/mainboard/lenovo/x220/me.bin \
   skip=12288 count=5230592 bs=1M iflag=count_bytes,skip_bytes
  • Compile coreboot
  • Flash the resulting build/coreboot.rom

If you have trouble reading the chip successfully, the most common problems are

  • insufficient power supply
  • bad contacts
  • too long wires
  • bad pinout

The cable shipped with buspirate was too long, and needed to be trimmed.

See also In-System Programming