board: siemens: Add support for SIMATIC IOT2050 devices

This adds support for the IOT2050 Basic and Advanced devices. The Basic
used the dual-core AM6528 GP processor, the Advanced one the AM6548 HS
quad-core version.

Both variants are booted via a Siemens-provided FSBL that runs on the R5
cores. Consequently, U-Boot support is targeting the A53 cores. U-Boot
SPL, ATF and TEE have to reside in SPI flash.

Full integration into a bootable image can be found on
https://github.com/siemens/meta-iot2050

Based on original board support by Le Jin, Gao Nian and Chao Zeng.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
diff --git a/board/siemens/iot2050/Kconfig b/board/siemens/iot2050/Kconfig
new file mode 100644
index 0000000..8f634c1
--- /dev/null
+++ b/board/siemens/iot2050/Kconfig
@@ -0,0 +1,32 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# Copyright (c) Siemens AG, 2018-2021
+#
+# Authors:
+#   Le Jin <le.jin@siemens.com>
+#   Jan Kiszka <jan.kiszka@siemens.com>
+
+config TARGET_IOT2050_A53
+	bool "IOT2050 running on A53"
+	select ARM64
+	select SOC_K3_AM6
+	select BOARD_LATE_INIT
+	select SYS_DISABLE_DCACHE_OPS
+	select BINMAN
+
+if TARGET_IOT2050_A53
+
+config SYS_BOARD
+	default "iot2050"
+
+config SYS_VENDOR
+	default "siemens"
+
+config SYS_CONFIG_NAME
+	default "iot2050"
+
+config IOT2050_BOOT_SWITCH
+	bool "Disable eMMC boot via USER button (Advanced version only)"
+	default y
+
+endif