Documentation/mainboard/lenovo: Add ThinkCentre M700/M900 Tiny

Heavily based on M710s documentation.

Change-Id: I8c3860ba6254919769082c9ed749f8bb287a5f5e
Signed-off-by: Michał Kopeć <michal.kopec@3mdeb.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/87044
Reviewed-by: Nicholas Chin <nic.c3.14@gmail.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

Documentation/mainboard/index.md

@@ -186,6 +186,7 @@ Mainboard codenames <lenovo/codenames.md>
 Hardware Maintenance Manual of ThinkPads <lenovo/thinkpad_hmm.md>
 R60 <lenovo/r60.md>
 ThinkCentre M710s <lenovo/thinkcentre_m710s.md>
+ThinkCentre M700 / M900 Tiny <lenovo/thinkcentre_m900_tiny.md>
 T4xx common <lenovo/t4xx_series.md>
 X2xx common <lenovo/x2xx_series.md>
 M920 Tiny <lenovo/m920q.md>

Documentation/mainboard/lenovo/thinkcentre_m900_tiny.md

@@ -0,0 +1,88 @@
+# Lenovo ThinkCentre M700 / M900 Tiny
+
+This page provides technical documentation on [Lenovo ThinkCentre M700 / M900 Tiny].
+
+M700 Tiny and M900 Tiny are twin designs using the same exact mainboard, with
+the following differences:
+
+```{eval-rst}
++------------------------+------+------+
+|        Feature         | M700 | M900 |
++========================+======+======+
+| Chipset                | B150 | Q170 |
++------------------------+------+------+
+| Intel AMT              | No   | Yes  |
++------------------------+------+------+
+| Intel TXT              | No   | Yes  |
++------------------------+------+------+
+| PCIe lanes in M.2 slot | No   | Yes  |
++------------------------+------+------+
+```
+
+## Flash chip
+
+```{eval-rst}
++----------+--------------------------+
+|   Type   |          Value           |
++==========+==========================+
+| Socketed | no                       |
++----------+--------------------------+
+| Model    | W25Q128.V or MX25L12873F |
++----------+--------------------------+
+| Size     | 16MiB                    |
++----------+--------------------------+
+| Package  | SOIC-8                   |
++----------+--------------------------+
+```
+
+The flash chip is divided into the following regions.
+
+	00000000:00000fff fd
+	00001000:00002fff gbe
+	00003000:007fffff me
+	00800000:00ffffff bios
+
+## Flashing
+
+The flash chip cannot be flashed internally when running vendor firmware, and must
+be flashed externally using a programmer of your choice.
+
+Steps on how to open the chassis and get access to the mainboard are described
+in the [hardware maintenance manual]. Follow the steps shown from
+"[Removing the computer cover]" until "[Replacing the M.2 storage drive]".
+
+The SPI flash should be easy to identify and the location is shown in the image
+below. See the [datasheet] and [flashing firmware tutorial] for more information.
+
+![](thinkcentre_m900_tiny_spi_location.jpg)
+
+## Status
+
+### Working
+
+ * Debian 12 (Linux 6.1.0) using MrChromebox' EDK II fork (uefipayload_2502)
+ * M.2 SATA + NVMe slot
+ * M.2 Wi-Fi slot
+ * Display ports
+ * USB
+ * Audio
+ * LAN
+ * CPU fan
+ * Discrete TPM 1.2
+ * Internal flashing (from coreboot)
+ * COM1 header
+ * DisplayPort header
+ * Power LED
+ * S3 Suspend
+
+### Untested
+
+ * PS/2 header
+ * PCIe + SATA "2L" expansion header
+
+[Lenovo ThinkCentre M700 / M900 Tiny]: https://psref.lenovo.com/syspool/Sys/PDF/ThinkCentre/ThinkCentre_M900_Tiny/ThinkCentre_M900_Tiny_Spec.PDF
+[hardware maintenance manual]: https://download.lenovo.com/pccbbs/thinkcentre_pdf/m700_m900_m900x_tiny_hmm.pdf
+[Removing the computer cover]: https://download.lenovo.com/pccbbs/thinkcentre_pdf/m700_m900_m900x_tiny_hmm.pdf#page=119
+[Replacing the M.2 storage drive]: https://download.lenovo.com/pccbbs/thinkcentre_pdf/m700_m900_m900x_tiny_hmm.pdf#page=134
+[datasheet]: https://www.mouser.com/datasheet/2/949/w25q128jv_revf_03272018_plus-1489608.pdf
+[flashing firmware tutorial]: ../../tutorial/flashing_firmware/index.md