Change in ...coreboot[master]: mb/lenovo/x220: Add x1 as a variant

[Bill XIE (Code Review)]

Hello Patrick Rudolph, Angel Pons, build bot (Jenkins), Nico Huber,

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/29434

to look at the new patch set (#9).

Change subject: mb/lenovo/x220: Add x1 as a variant
......................................................................

mb/lenovo/x220: Add x1 as a variant

ThinkPad X1 ( https://www.thinkwiki.org/wiki/Category:X1 ) is nearly a
clone of X220, with additional USB3 controller on pci-e (as i7 variant
of x220), and a powered ESATA port wired to ata4 (Linux' annotation).

Documentation added.

Tested:
- CPU i5-2520M
- Slotted DIMM 8GiB
- Camera
- Mini pci-e on wlan slot
- Msata on wwan slot
- On board SDHCI connected to pci-e
- USB3 controller connected to pci-e
- NVRAM options for North and South bridges
- S3
- TPM1 on LPC
- Linux 4.9.110-3 within Debian GNU/Linux stable, loaded from
  SeaBIOS, or Linux payload (Heads)

Not tested:
- Fingerprint reader on USB2
- Onboard USB2 interfaces (wlan slot, wwan slot)

Change-Id: Ibbc45f22c63b77ac95c188db825d0d7e2b03d2d1
Signed-off-by: Bill XIE 
---
M Documentation/mainboard/index.md
M Documentation/mainboard/lenovo/t4xx_series.md
A Documentation/mainboard/lenovo/thinkpad_hmm.md
A Documentation/mainboard/lenovo/x1.md
A Documentation/mainboard/lenovo/x1_flash_ic.png
A Documentation/mainboard/lenovo/x2xx_series.md
M src/mainboard/lenovo/x220/Kconfig
M src/mainboard/lenovo/x220/Kconfig.name
M src/mainboard/lenovo/x220/Makefile.inc
M src/mainboard/lenovo/x220/devicetree.cb
M src/mainboard/lenovo/x220/romstage.c
A src/mainboard/lenovo/x220/variants/x1/data.vbt
A src/mainboard/lenovo/x220/variants/x1/gpio.c
A src/mainboard/lenovo/x220/variants/x1/overridetree.cb
A src/mainboard/lenovo/x220/variants/x1/romstage.c
R src/mainboard/lenovo/x220/variants/x220/data.vbt
R src/mainboard/lenovo/x220/variants/x220/gpio.c
A src/mainboard/lenovo/x220/variants/x220/overridetree.cb
A src/mainboard/lenovo/x220/variants/x220/romstage.c
19 files changed, 459 insertions(+), 24 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/34/29434/9