diff --git a/board/siemens/iot2050/board.c b/board/siemens/iot2050/board.c
index 2735ae3..df705b7 100644
--- a/board/siemens/iot2050/board.c
+++ b/board/siemens/iot2050/board.c
@@ -1,7 +1,7 @@
 // SPDX-License-Identifier: GPL-2.0+
 /*
  * Board specific initialization for IOT2050
- * Copyright (c) Siemens AG, 2018-2021
+ * Copyright (c) Siemens AG, 2018-2022
  *
  * Authors:
  *   Le Jin <le.jin@siemens.com>
@@ -11,9 +11,11 @@
 #include <common.h>
 #include <bootstage.h>
 #include <dm.h>
+#include <fdt_support.h>
 #include <i2c.h>
 #include <led.h>
 #include <malloc.h>
+#include <mapmem.h>
 #include <net.h>
 #include <phy.h>
 #include <spl.h>
@@ -47,6 +49,114 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
+struct gpio_config {
+	const char *gpio_name;
+	const char *label;
+};
+
+enum m2_connector_mode {
+	BKEY_PCIEX2 = 0,
+	BKEY_PCIE_EKEY_PCIE,
+	BKEY_USB30_EKEY_PCIE,
+	CONNECTOR_MODE_INVALID
+};
+
+struct m2_config_pins {
+	int config[4];
+};
+
+struct serdes_mux_control {
+	int ctrl_usb30_pcie0_lane0;
+	int ctrl_pcie1_pcie0;
+	int ctrl_usb30_pcie0_lane1;
+};
+
+struct m2_config_table {
+	struct m2_config_pins config_pins;
+	enum m2_connector_mode mode;
+};
+
+static const struct gpio_config serdes_mux_ctl_pin_info[] = {
+	{"gpio@600000_88", "CTRL_USB30_PCIE0_LANE0"},
+	{"gpio@600000_82", "CTRL_PCIE1_PCIE0"},
+	{"gpio@600000_89", "CTRL_USB30_PCIE0_LANE1"},
+};
+
+static const struct gpio_config m2_bkey_cfg_pin_info[] = {
+	{"gpio@601000_18", "KEY_CONFIG_0"},
+	{"gpio@601000_19", "KEY_CONFIG_1"},
+	{"gpio@601000_88", "KEY_CONFIG_2"},
+	{"gpio@601000_89", "KEY_CONFIG_3"},
+};
+
+static const struct m2_config_table m2_config_table[] = {
+	{{{0, 1, 0, 0}}, BKEY_PCIEX2},
+	{{{0, 0, 1, 0}}, BKEY_PCIE_EKEY_PCIE},
+	{{{0, 1, 1, 0}}, BKEY_PCIE_EKEY_PCIE},
+	{{{1, 0, 0, 1}}, BKEY_PCIE_EKEY_PCIE},
+	{{{1, 1, 0, 1}}, BKEY_PCIE_EKEY_PCIE},
+	{{{0, 0, 0, 1}}, BKEY_USB30_EKEY_PCIE},
+	{{{0, 1, 0, 1}}, BKEY_USB30_EKEY_PCIE},
+	{{{0, 0, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+	{{{0, 1, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+	{{{1, 0, 1, 1}}, BKEY_USB30_EKEY_PCIE},
+};
+
+static const struct serdes_mux_control serdes_mux_ctrl[] = {
+	[BKEY_PCIEX2]          = {0, 0, 1},
+	[BKEY_PCIE_EKEY_PCIE]  = {0, 1, 0},
+	[BKEY_USB30_EKEY_PCIE] = {1, 1, 0},
+};
+
+static const char *m2_connector_mode_name[] = {
+	[BKEY_PCIEX2]          = "PCIe x2 (key B)",
+	[BKEY_PCIE_EKEY_PCIE]  = "PCIe (key B) / PCIe (key E)",
+	[BKEY_USB30_EKEY_PCIE] = "USB 3.0 (key B) / PCIe (key E)",
+};
+
+static enum m2_connector_mode connector_mode;
+
+#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+static void *connector_overlay;
+static u32 connector_overlay_size;
+#endif
+
+static int get_pinvalue(const char *gpio_name, const char *label)
+{
+	struct gpio_desc gpio;
+
+	if (dm_gpio_lookup_name(gpio_name, &gpio) < 0 ||
+	    dm_gpio_request(&gpio, label) < 0 ||
+	    dm_gpio_set_dir_flags(&gpio, GPIOD_IS_IN) < 0) {
+		pr_err("Cannot get pin %s for M.2 configuration\n", gpio_name);
+		return 0;
+	}
+
+	return dm_gpio_get_value(&gpio);
+}
+
+static void set_pinvalue(const char *gpio_name, const char *label, int value)
+{
+	struct gpio_desc gpio;
+
+	if (dm_gpio_lookup_name(gpio_name, &gpio) < 0 ||
+	    dm_gpio_request(&gpio, label) < 0 ||
+	    dm_gpio_set_dir_flags(&gpio, GPIOD_IS_OUT) < 0) {
+		pr_err("Cannot set pin %s for M.2 configuration\n", gpio_name);
+		return;
+	}
+	dm_gpio_set_value(&gpio, value);
+}
+
+static bool board_is_m2(void)
+{
+	struct iot2050_info *info = IOT2050_INFO_DATA;
+
+	return IS_ENABLED(CONFIG_TARGET_IOT2050_A53_PG2) &&
+		info->magic == IOT2050_INFO_MAGIC &&
+		strcmp((char *)info->name, "IOT2050-ADVANCED-M2") == 0;
+}
+
 static bool board_is_advanced(void)
 {
 	struct iot2050_info *info = IOT2050_INFO_DATA;
@@ -103,6 +213,8 @@
 	if (board_is_advanced()) {
 		if (IS_ENABLED(CONFIG_TARGET_IOT2050_A53_PG1))
 			fdtfile = "ti/k3-am6548-iot2050-advanced.dtb";
+		else if(board_is_m2())
+			fdtfile = "ti/k3-am6548-iot2050-advanced-m2.dtb";
 		else
 			fdtfile = "ti/k3-am6548-iot2050-advanced-pg2.dtb";
 	} else {
@@ -118,6 +230,101 @@
 	env_save();
 }
 
+static void m2_overlay_prepare(void)
+{
+#if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+	const char *overlay_path;
+	void *overlay;
+	u64 loadaddr;
+	ofnode node;
+	int ret;
+
+	if (connector_mode == BKEY_PCIEX2)
+		return;
+
+	if (connector_mode == BKEY_PCIE_EKEY_PCIE)
+		overlay_path = "/fit-images/bkey-ekey-pcie-overlay";
+	else
+		overlay_path = "/fit-images/bkey-usb3-overlay";
+
+	node = ofnode_path(overlay_path);
+	if (!ofnode_valid(node))
+		goto fit_error;
+
+	ret = ofnode_read_u64(node, "load", &loadaddr);
+	if (ret)
+		goto fit_error;
+
+	ret = ofnode_read_u32(node, "size", &connector_overlay_size);
+	if (ret)
+		goto fit_error;
+
+	overlay = map_sysmem(loadaddr, connector_overlay_size);
+
+	connector_overlay = malloc(connector_overlay_size);
+	if (!connector_overlay)
+		goto fit_error;
+
+	memcpy(connector_overlay, overlay, connector_overlay_size);
+	return;
+
+fit_error:
+	pr_err("M.2 device tree overlay %s not available,\n", overlay_path);
+#endif
+}
+
+static void m2_connector_setup(void)
+{
+	ulong m2_manual_config = env_get_ulong("m2_manual_config", 10,
+					       CONNECTOR_MODE_INVALID);
+	const char *mode_info = "";
+	struct m2_config_pins config_pins;
+	unsigned int n;
+
+	/* enable M.2 connector power */
+	set_pinvalue("gpio@601000_17", "P3V3_M2_EN", 1);
+	udelay(4 * 100);
+
+	if (m2_manual_config < CONNECTOR_MODE_INVALID) {
+		mode_info = " [manual mode]";
+		connector_mode = m2_manual_config;
+	} else { /* auto detection */
+		for (n = 0; n < ARRAY_SIZE(config_pins.config); n++)
+			config_pins.config[n] =
+				get_pinvalue(m2_bkey_cfg_pin_info[n].gpio_name,
+					     m2_bkey_cfg_pin_info[n].label);
+		connector_mode = CONNECTOR_MODE_INVALID;
+		for (n = 0; n < ARRAY_SIZE(m2_config_table); n++) {
+			if (!memcmp(config_pins.config,
+				    m2_config_table[n].config_pins.config,
+				    sizeof(config_pins.config))) {
+				connector_mode = m2_config_table[n].mode;
+				break;
+			}
+		}
+		if (connector_mode == CONNECTOR_MODE_INVALID) {
+			mode_info = " [fallback, card unknown/unsupported]";
+			connector_mode = BKEY_USB30_EKEY_PCIE;
+		}
+	}
+
+	printf("M.2:   %s%s\n", m2_connector_mode_name[connector_mode],
+	       mode_info);
+
+	/* configure serdes mux */
+	set_pinvalue(serdes_mux_ctl_pin_info[0].gpio_name,
+		     serdes_mux_ctl_pin_info[0].label,
+		     serdes_mux_ctrl[connector_mode].ctrl_usb30_pcie0_lane0);
+	set_pinvalue(serdes_mux_ctl_pin_info[1].gpio_name,
+		     serdes_mux_ctl_pin_info[1].label,
+		     serdes_mux_ctrl[connector_mode].ctrl_pcie1_pcie0);
+	set_pinvalue(serdes_mux_ctl_pin_info[2].gpio_name,
+		     serdes_mux_ctl_pin_info[2].label,
+		     serdes_mux_ctrl[connector_mode].ctrl_usb30_pcie0_lane1);
+
+	m2_overlay_prepare();
+}
+
 int board_init(void)
 {
 	return 0;
@@ -215,6 +422,9 @@
 	/* change CTRL_MMR register to let serdes0 not output USB3.0 signals. */
 	writel(0x3, SERDES0_LANE_SELECT);
 
+	if (board_is_m2())
+		m2_connector_setup();
+
 	set_board_info_env();
 
 	/* remove the eMMC if requested via button */
@@ -226,6 +436,50 @@
 }
 
 #if defined(CONFIG_OF_LIBFDT) && defined(CONFIG_OF_BOARD_SETUP)
+static void m2_fdt_fixup(void *blob)
+{
+	void *overlay_copy = NULL;
+	void *fdt_copy = NULL;
+	u32 fdt_size;
+	int err;
+
+	if (!connector_overlay)
+		return;
+
+	/*
+	 * We need to work with temporary copies here because fdt_overlay_apply
+	 * is destructive to the overlay and also to the target blob, even if
+	 * application fails.
+	 */
+	fdt_size = fdt_totalsize(blob);
+	fdt_copy = malloc(fdt_size);
+	if (!fdt_copy)
+		goto fixup_error;
+
+	memcpy(fdt_copy, blob, fdt_size);
+
+	overlay_copy = malloc(connector_overlay_size);
+	if (!overlay_copy)
+		goto fixup_error;
+
+	memcpy(overlay_copy, connector_overlay, connector_overlay_size);
+
+	err = fdt_overlay_apply_verbose(fdt_copy, overlay_copy);
+	if (err)
+		goto fixup_error;
+
+	memcpy(blob, fdt_copy, fdt_size);
+
+cleanup:
+	free(fdt_copy);
+	free(overlay_copy);
+	return;
+
+fixup_error:
+	pr_err("Could not apply M.2 device tree overlay\n");
+	goto cleanup;
+}
+
 int ft_board_setup(void *blob, struct bd_info *bd)
 {
 	int ret;
@@ -237,6 +491,9 @@
 	if (ret)
 		pr_err("%s: fixing up msmc ram failed %d\n", __func__, ret);
 
+	if (board_is_m2())
+		m2_fdt_fixup(blob);
+
 	return ret;
 }
 #endif