Board:lenovo/x201

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Revision as of 23:26, 18 March 2017 by SamPabloKuper (talk | contribs) (Method 2: external flasher: Delineate subsection)
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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 X201 port.

Issues:

  • Sometimes Gnome starts to think that battery is 10 time larger than real. Information from sysfs remains correct. Doesn't appear in newer gnome
  • Yellow USB port is not powered when computer is shut down or in S3.
  • Most times after suspend an EC IRQ hangs in the queue and all functions keys stopped working until cold boot.
  • Commit 456f495d broke USB and PCI-E (unable to boot from live ISO on USB), a hard reset to commit a3e41c08 fixed the boot issue, however the following issues occured/persisted:

Tested:

  • RAM module combinations of 4G+4G, 4G, 2G+2G,4G+2G, 2G
  • suspend to RAM (S3) (see issue mentioned above)
  • USB (see issues mentioned above)
  • Video (both internal and VGA)
  • Expresscard slot (including hotplug)
  • Sound
  • LAN
  • mini-PCIe slots (both wlan and wwan)
  • Linux (through GRUB-as-payload & SeaBIOS-as-payload)
  • Windows (through GRUB-as-payload loading SeaBIOS image from disk; you have to use extracted VGA blob, dumped from memory isn't good enough)
  • SD card slot
  • Thermal management
  • Fingerprint reader
  • Webcam
  • Bluetooth
  • Digitizer on X201t variant.

Not tested:

  • Modem

proprietary components status

  • CPU Microcode
  • VGA Option ROM (optional): you need it if you want graphics in SeaBIOS but most payloads (e.g. GRUB2) work just fine without it (text mode or corebootfb mode)
  • [[Intel_Management_Engine|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)

Code

 $ git clone https://review.coreboot.org/coreboot.git


Flashing

Background info: flash layout

The flash memory in the X201 is divided into roughly 4 parts, readable and writable thus:

Part Size With Flashrom on
the running system
With Flashrom via
an external programmer
Readable Writable Readable Writable
Descriptor 12K Yes No Yes Yes
ME firmware 5M minus 12K No No Yes Yes
Rewriteable flash 3M minus 96K Yes Yes Yes Yes
Locked bootblock 96K Yes No Yes Yes

To install coreboot onto the X201, we need to preserve the descriptor and the ME firmware, and to overwrite the rewriteable region and the bootblock. There are two ways to achieve this:

  • External flasher.
  • Unlock bootblock.

Method 1: external flasher

In addition to your X201, you will need an external SPI flasher supported by Flashrom, connected to a PC capable of running Flashrom.

Read the flash chip contents

Turn off your X201.

Remove the following:

  • battery;
  • keyboard;
  • palmrest.

Locate the SPI chip. It should be beneath a protective plastic sheet, under where the keyboard was, at roughly the location where the trackpoint was.

Found it!
Under the keyboard
The SPI chip


Connect your external SPI flasher to the SPI chip, ideally using a SOIC-8 clip.

The pinout is as follows. (The colors in parentheses are those used by the Bus Pirate breakout cable; your programmer may use leads with different colors.)

^ Towards LCD display (i.e. away from you)
|

   (red)        (violet) (gray)
   3.3V    N/C     CLK    MOSI
   _|_______|_______|_______|_
  |                           |
  |                           |
  |                           |
  |                           |
  |___________________________|
    |       |       |       |
   CS      MISO    N/C     GND
  (white) (black)        (brown)

|
v Towards front edge of laptop base (i.e. towards you)


Not all external programmers supply enough current to enable reliable reads from and writes to the flash chip. If yours does not (as is the case with the Bus Pirate and the BeagleBone Black), then you may have to use a more powerful regulated power supply to feed the chip's 3.3V pin. Make sure not to exceed 3.3V.

Read the flash chip's contents at least twice, using Flashrom. Compare the files to be sure they are identical.

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

If you have trouble reading the chip successfully, check for an eliminate these common problems:

  • insufficient power supply;
  • bad contacts;
  • excessively long wires (even 10cm may be too long);
  • incorrect connections.

For additional troubleshooting, see: In-System Programming.

Once you have a good copy of the flash chip's contents, save a copy of the file to external media as a backup.

  • Recover descriptor and ME firmare:
 dd if=flash.bin of=coreboot/3rdparty/mainboard/lenovo/x201/descriptor.bin \
   count=12288 bs=1M iflag=count_bytes
 dd if=flash.bin of=coreboot/3rdparty/mainboard/lenovo/x201/me.bin \
   skip=12288 count=5230592 bs=1M iflag=count_bytes,skip_bytes
  • Compile coreboot. Remember to enable HAVE_IFD and HAVE_ME_BIN
  • Flash the resulting build/coreboot.rom


Method 2: unlocking the bootblock

No-one has so far published any success with this method. In theory, however, it is possible.

The locking mechanism is in the bootblock itself. The original firmware has a way to update it as follows.

Flash an update of rewriteable region. On next boot bootblock parses the image and sees that it contains a compressed copy of new bootblock. That copy is uncompressed and flashed. A way to unlock the bootblock would be to modify a firmware update to have a copy of bootblock without protection. For this you need to compress the modified block to fit into original space. The compression used is Lempel-Ziv- Huffman variant. I've written a compressor for it but unfortunately it's not performant enough.

identify the regions

[root@x201 ~]# flashrom -r bios.bin -pinternal:laptop=force_I_want_a_brick
flashrom v0.9.6.1-r1563 on Linux 3.10-1-grml-amd64 (x86_64)
flashrom is free software, get the source code at http://www.flashrom.org

Calibrating delay loop... OK.
Found chipset "Intel QM57". Enabling flash write... WARNING: SPI Configuration Lockdown activated.
FREG0: WARNING: Flash Descriptor region (0x00000000-0x00000fff) is read-only.
FREG2: WARNING: Management Engine region (0x00003000-0x004fffff) is locked.
PR0: WARNING: 0x007d0000-0x01ffffff is read-only.
Please send a verbose log to flashrom@flashrom.org if this board is not listed on
http://flashrom.org/Supported_hardware#Supported_mainboards yet.
Writes have been disabled. You can enforce write support with the
ich_spi_force programmer option, but it will most likely harm your hardware!
If you force flashrom you will get no support if something breaks.
OK.
Found Macronix flash chip "MX25L6405" (8192 kB, SPI) at physical address 0xff800000.
Reading flash... FAILED.

it will print the ME regions:

FREG2: WARNING: Management Engine region (0x00003000-0x004fffff) is locked.

it will also print the chip:

Found Macronix flash chip "MX25L6405" (8192 kB, SPI) at physical address 0xff800000.

But as in this case, flashrom might misidentify the chip, this output is from this MX25L6445E

visually verify your chip's part number and find an appropriate datasheet

=>verify that its voltage matches with the programmer voltage...

  • Use flashrom layouts:
       -l, --layout <file>

X201 Layout

000000000:00000fff fd
000001000:00002fff gbe
000003000:004fffff me
000500000:007fffff bios

To flash only the bios partition (coreboot + payload) do:

flashrom -l <layout> -i bios -w coreboot.rom