imx: kontron-sl-mx8mm: Add support for Kontron Electronics SoM SL i.MX8MM OSM-S

This adds support for the Kontron Electronics SoM SL i.MX8MM OSM-S
and the matching baseboard BL i.MX8MM OSM-S.

The SoM hardware complies to the Open Standard Module (OSM) 1.0
specification, size S (https://sget.org/standards/osm).

The existing board configuration for the non-OSM SoM is reused and
allows to detect the SoM variant at runtime.

Signed-off-by: Frieder Schrempf <frieder.schrempf@kontron.de>
Reviewed-by: Fabio Estevam <festevam@denx.de>
diff --git a/arch/arm/dts/imx8mm-kontron-bl-common-u-boot.dtsi b/arch/arm/dts/imx8mm-kontron-bl-common-u-boot.dtsi
new file mode 100644
index 0000000..e7e900d
--- /dev/null
+++ b/arch/arm/dts/imx8mm-kontron-bl-common-u-boot.dtsi
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0+ OR MIT
+/*
+ * Copyright (C) 2019 Kontron Electronics GmbH
+ */
+
+#include "imx8mm-u-boot.dtsi"
+
+/ {
+	aliases {
+		usb0 = &usbotg1;
+		usb1 = &usbotg2;
+	};
+
+	wdt-reboot {
+		compatible = "wdt-reboot";
+		wdt = <&wdog1>;
+		u-boot,dm-spl;
+	};
+
+	firmware {
+		optee {
+			compatible = "linaro,optee-tz";
+			method = "smc";
+		};
+	};
+};
+
+&crypto {
+	u-boot,dm-spl;
+};
+
+&sec_jr0 {
+	u-boot,dm-spl;
+};
+
+&sec_jr1 {
+	u-boot,dm-spl;
+};
+
+&sec_jr2 {
+	u-boot,dm-spl;
+};
+
+&i2c1 {
+	u-boot,dm-spl;
+	u-boot,dm-pre-reloc;
+};
+
+&i2c2 {
+	status = "okay";
+	u-boot,dm-spl;
+	u-boot,dm-pre-reloc;
+};
+
+&pinctrl_ecspi1 {
+	u-boot,dm-spl;
+};
+
+&pinctrl_i2c1 {
+	u-boot,dm-spl;
+};
+
+&pinctrl_pmic {
+	u-boot,dm-spl;
+};
+
+&pinctrl_uart3 {
+	u-boot,dm-spl;
+	u-boot,dm-pre-reloc;
+};
+
+&pinctrl_usdhc1 {
+	u-boot,dm-spl;
+};
+
+&pinctrl_usdhc1_100mhz {
+	u-boot,dm-spl;
+};
+
+&pinctrl_usdhc1_200mhz {
+	u-boot,dm-spl;
+};
+
+&pinctrl_usdhc2 {
+	u-boot,dm-spl;
+};
+
+&pca9450 {
+	u-boot,dm-spl;
+};
+
+&{/soc@0/bus@30800000/i2c@30a20000/pmic@25/regulators} {
+	u-boot,dm-spl;
+};
+
+&ecspi1 {
+	u-boot,dm-spl;
+};
+
+&gpio1 {
+	u-boot,dm-spl;
+};
+
+&gpio2 {
+	u-boot,dm-spl;
+};
+
+&gpio3 {
+	u-boot,dm-spl;
+};
+
+&gpio4 {
+	u-boot,dm-spl;
+};
+
+&gpio5 {
+	u-boot,dm-spl;
+};
+
+&uart3 {
+	u-boot,dm-spl;
+	u-boot,dm-pre-reloc;
+};
+
+&usdhc1 {
+	u-boot,dm-spl;
+};
+
+&usdhc2 {
+	u-boot,dm-spl;
+};
+
+&wdog1 {
+	u-boot,dm-spl;
+};
+
+&pinctrl_wdog {
+	u-boot,dm-spl;
+};