mb/supermicro: Add X9SAE and X9SAE-V

Mainboard information can be found in the included documentation.

Change-Id: I9dfc58bb99e14cd9dac2ac53afc0ea11d2252aa9
Signed-off-by: Bill XIE <persmule@hardenedlinux.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/57191
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>

Documentation/mainboard/supermicro/x9sae.md

@@ -0,0 +1,108 @@
+# Supermicro X9SAE and X9SAE-V
+
+This page describes how to run coreboot on the Supermicro [X9SAE] and [X9SAE-V]
+
+## Flashing coreboot
+
+```eval_rst
++---------------------+----------------+
+| Type                | Value          |
++=====================+================+
+| Socketed flash      | occasionally   |
++---------------------+----------------+
+| Model               | W25Q128FVSG    |
++---------------------+----------------+
+| Size                | 16 MiB         |
++---------------------+----------------+
+| Package             | SOIC-8         |
++---------------------+----------------+
+| Write protection    | no             |
++---------------------+----------------+
+| Dual BIOS feature   | no             |
++---------------------+----------------+
+| Internal flashing   | yes            |
++---------------------+----------------+
+```
+
+The flash IC is located between the PCH and the front panel connector,
+(circled) sometimes it is socketed.
+![](x9sae.jpg)
+
+### How to flash
+
+Unlike ordinary desktop boards, the BIOS version 2.00 of X9SAE-V does not
+apply any write protection, so the main SPI flash can be accessed using
+[flashrom], and the whole flash is writable.
+
+Note: If you are going to modify the ME region via internal programming, you had
+better disable ME functionalities as much as possible in the vendor firmware
+first, otherwise ME may write something back and break the firmware you write.
+
+The following command may be used to flash coreboot. (To do so, linux kernel
+could be started with `iomem=relaxed` or unload the `lpc_ich` kernel module)
+
+Now you can [flash internally](/flash_tutorial/int_flashrom.md). It is
+recommended to flash only the `bios` region (use `--ifd -i bios -N` flashrom
+arguments), in order to minimize the chances of messing something up in the
+beginning.
+
+The flash chip is a SOIC-8 SPI flash, and may be socketed, so it's also easy
+to do in-system programming, or remove and flash externally if it is socketed.
+
+## Difference between X9SAE and X9SAE-V
+On X9SAE PCI-E slot 4 is absent. Lane 9~16 of PCI-E slot 6 on X9SAE are wired
+to slot 4 on X9SAE-V. Unlike ASUS P8C WS, there is no dynamic switch on X9SAE-V,
+so on X9SAE-V slot 6 can work as x8 at most.
+
+On X9SAE-V device pci 01.1 appears even if not defined in devicetree.cb, so it
+seems that it shall not appear on X9SAE even if it is defined.
+
+## Working (on my X9SAE-V)
+- Intel Xeon E3-1225 V2 with 4 M391B1G73BH0-YK0 UDIMMs, ECC confirmed active
+- PS/2 keyboard with SeaBIOS 1.14.0 and Debian GNU/Linux with kernel 5.10.46
+- Use PS/2 keyboard and mouse simutaneously with a PS/2 Y-cable
+- Both Onboard NIC
+- S3 Suspend to RAM
+- USB2 on rear and front panel connectors
+- USB3
+- Integrated SATA
+- CPU Temp sensors (tested PSensor on GNU/Linux)
+- LPC TPM on TPM-header (tested tpm-tools with TPM 1.2 Infineon SLB9635TT12)
+- Native raminit
+- Integrated graphics with libgfxinit
+- Nvidia Quadro 600 in all PCIe-16x slots
+- Compex WLM200NX (Qualcomm Atheros AR9220) in PCI slot
+- Debug output from serial port
+
+## Untested
+
+- EHCI debugging
+- S/PDIF audio
+- PS/2 mouse
+
+## Technology
+
+```eval_rst
++------------------+--------------------------------------------------+
+| Northbridge      | :doc:`../../northbridge/intel/sandybridge/index` |
++------------------+--------------------------------------------------+
+| Southbridge      | bd82x6x                                          |
++------------------+--------------------------------------------------+
+| CPU              | model_206ax                                      |
++------------------+--------------------------------------------------+
+| Super I/O        | Nuvoton NCT6776F                                 |
++------------------+--------------------------------------------------+
+| EC               | None                                             |
++------------------+--------------------------------------------------+
+| Coprocessor      | Intel Management Engine                          |
++------------------+--------------------------------------------------+
+```
+
+## Extra resources
+
+- [Flash chip datasheet][W25Q128FVSG]
+
+[X9SAE]: https://www.supermicro.com/products/motherboard/xeon/c216/x9sae.cfm
+[X9SAE-V]:  https://www.supermicro.com/products/motherboard/xeon/c216/x9sae-v.cfm
+[W25Q128FVSG]: https://static.chipdip.ru/lib/093/DOC001093213.pdf
+[flashrom]: https://flashrom.org/Flashrom