imx: imx8mm: Add support for Kontron Electronics SL/BL i.MX8M-Mini boards (N801x)

The Kontron SoM-Line i.MX8MM (N801x) by Kontron Electronics GmbH is a SoM
module with an i.MX8M-Mini SoC, 1/2/4 GB LPDDR4 RAM, SPI NOR, eMMC and PMIC.

The matching evaluation boards (Board-Line) have 2 Ethernets, USB 2.0, HDMI/LVDS,
SD card, CAN, RS485 and much more.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Stefano Babic <sbabic@denx.de>
Tested-by: Heiko Thiery <heiko.thiery@gmail.com>

2 files changed, 86 insertions, 0 deletions

diff --git a/doc/board/kontron/index.rst b/doc/board/kontron/index.rst
index c3fadcef76..7dfe3d9bc0 100644
--- a/doc/board/kontron/index.rst
+++ b/doc/board/kontron/index.rst
@@ -8,3 +8,4 @@ Kontron
 
    sl28
    sl-mx6ul
+   sl-mx8mm
diff --git a/doc/board/kontron/sl-mx8mm.rst b/doc/board/kontron/sl-mx8mm.rst
new file mode 100644
index 0000000000..74ff228f20
--- /dev/null
+++ b/doc/board/kontron/sl-mx8mm.rst
@@ -0,0 +1,85 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+Kontron Electronics SL i.MX8MM SoM
+==================================
+
+The Kontron SoM-Line i.MX8MM (N801x) by Kontron Electronics GmbH is a SoM module
+with an i.MX8M-Mini SoC, 1/2/4 GB LPDDR4 RAM, SPI NOR, eMMC and PMIC.
+
+The matching evaluation boards (Board-Line) have two Ethernet ports, USB 2.0,
+HDMI/LVDS, SD card, CAN, RS485, RS232 and much more.
+
+Quick Start
+-----------
+
+- Get and Build the Trusted Firmware-A (TF-A)
+- Get the DDR firmware
+- Build U-Boot
+- Boot
+
+Get and Build the Trusted Firmware-A (TF-A)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Note: builddir is U-Boot build directory (source directory for in-tree builds)
+
+There are two sources for the TF-A. Mainline and NXP. Get the one you prefer
+(support and features might differ).
+
+**NXP's imx-atf**
+
+1. Get TF-A from: https://source.codeaurora.org/external/imx/imx-atf, branch: imx_5.4.70_2.3.0
+2. Apply the patch to select the correct UART for the console, otherwise the TF-A will lock up during boot.
+3. Build
+
+  .. code-block:: bash
+
+     $ make PLAT=imx8mm bl31
+     $ cp build/imx8mm/release/bl31.bin $(builddir)
+
+**Mainline TF-A**
+
+1. Get TF-A from: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/, tag: v2.4
+2. Build
+
+  .. code-block:: bash
+
+     $ make PLAT=imx8mm CROSS_COMPILE=aarch64-linux-gnu- IMX_BOOT_UART_BASE="0x30880000" bl31
+     $ cp build/imx8mm/release/bl31.bin $(builddir)
+
+Get the DDR firmware
+^^^^^^^^^^^^^^^^^^^^
+
+.. code-block:: bash
+
+   $ wget https://www.nxp.com/lgfiles/NMG/MAD/YOCTO/firmware-imx-8.9.bin
+   $ chmod +x firmware-imx-8.9.bin
+   $ ./firmware-imx-8.9.bin
+   $ cp firmware-imx-8.9/firmware/ddr/synopsys/lpddr4*.bin $(builddir)
+
+Build U-Boot
+^^^^^^^^^^^^
+
+.. code-block:: bash
+
+   $ make kontron-sl-mx8mm_defconfig
+   $ export ATF_LOAD_ADDR=0x920000
+   $ make
+
+Burn the flash.bin to SD card at an offset of 33 KiB:
+
+.. code-block:: bash
+
+   $ dd if=flash.bin of=/dev/sd[x] bs=1K seek=33 conv=notrunc
+
+Boot
+^^^^
+
+Put the SD card in the slot on the board and apply power.
+
+Further Information
+-------------------
+
+The bootloader configuration is setup to be used with kernel FIT images. Legacy
+images might not be working out of the box.
+
+Please see https://docs.kontron-electronics.de for further vendor documentation.