diff --git a/src/mainboard/google/rex/Kconfig b/src/mainboard/google/rex/Kconfig
index d848ac71f2..dbccce6770 100644
--- a/src/mainboard/google/rex/Kconfig
+++ b/src/mainboard/google/rex/Kconfig
@@ -7,6 +7,8 @@ config BOARD_GOOGLE_REX_COMMON
 config BOARD_GOOGLE_BASEBOARD_REX
 	def_bool n
 	select BOARD_GOOGLE_REX_COMMON
+	select EC_GOOGLE_CHROMEEC
+	select EC_GOOGLE_CHROMEEC_ESPI
 	select SOC_INTEL_METEORLAKE
 	select SYSTEM_TYPE_LAPTOP
 
@@ -19,6 +21,10 @@ config BASEBOARD_DIR
 	string
 	default "rex" if BOARD_GOOGLE_BASEBOARD_REX
 
+config CHROMEOS
+	select GBB_FLAG_DISABLE_EC_SOFTWARE_SYNC
+	select VBOOT_LID_SWITCH
+
 config DEVICETREE
 	default "variants/baseboard/\$(CONFIG_BASEBOARD_DIR)/devicetree.cb"
 
diff --git a/src/mainboard/google/rex/Makefile.inc b/src/mainboard/google/rex/Makefile.inc
index f839c328fd..cab45dfa2a 100644
--- a/src/mainboard/google/rex/Makefile.inc
+++ b/src/mainboard/google/rex/Makefile.inc
@@ -3,6 +3,7 @@ bootblock-y += bootblock.c
 romstage-y += romstage.c
 
 ramstage-y += mainboard.c
+ramstage-y += ec.c
 
 VARIANT_DIR:=$(call strip_quotes,$(CONFIG_VARIANT_DIR))
 BASEBOARD_DIR:=$(call strip_quotes,$(CONFIG_BASEBOARD_DIR))
diff --git a/src/mainboard/google/rex/dsdt.asl b/src/mainboard/google/rex/dsdt.asl
index cecfe521fa..c967f5a3ff 100644
--- a/src/mainboard/google/rex/dsdt.asl
+++ b/src/mainboard/google/rex/dsdt.asl
@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: GPL-2.0-or-later */
 
 #include <acpi/acpi.h>
+#include <variant/ec.h>
 
 DefinitionBlock(
 	"dsdt.aml",
@@ -31,4 +32,13 @@ DefinitionBlock(
 
 	/* Chipset specific sleep states */
 	#include <southbridge/intel/common/acpi/sleepstates.asl>
+
+	/* Chrome OS Embedded Controller */
+	Scope (\_SB.PCI0.LPCB)
+	{
+		/* ACPI code for EC SuperIO functions */
+		#include <ec/google/chromeec/acpi/superio.asl>
+		/* ACPI code for EC functions */
+		#include <ec/google/chromeec/acpi/ec.asl>
+	}
 }
diff --git a/src/mainboard/google/rex/ec.c b/src/mainboard/google/rex/ec.c
new file mode 100644
index 0000000000..f828bc5547
--- /dev/null
+++ b/src/mainboard/google/rex/ec.c
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#include <acpi/acpi.h>
+#include <console/console.h>
+#include <ec/ec.h>
+#include <ec/google/chromeec/ec.h>
+#include <variant/ec.h>
+
+void mainboard_ec_init(void)
+{
+	static const struct google_chromeec_event_info info = {
+		.log_events = MAINBOARD_EC_LOG_EVENTS,
+		.sci_events = MAINBOARD_EC_SCI_EVENTS,
+		.s3_wake_events = MAINBOARD_EC_S3_WAKE_EVENTS,
+		.s5_wake_events = MAINBOARD_EC_S5_WAKE_EVENTS,
+		.s0ix_wake_events = MAINBOARD_EC_S0IX_WAKE_EVENTS,
+	};
+
+	printk(BIOS_DEBUG, "mainboard: EC init\n");
+
+	google_chromeec_events_init(&info, acpi_is_wakeup_s3());
+}
diff --git a/src/mainboard/google/rex/mainboard.c b/src/mainboard/google/rex/mainboard.c
index d7c31565b9..f3fef836dc 100644
--- a/src/mainboard/google/rex/mainboard.c
+++ b/src/mainboard/google/rex/mainboard.c
@@ -2,6 +2,7 @@
 
 #include <baseboard/variants.h>
 #include <device/device.h>
+#include <ec/ec.h>
 
 static void mainboard_init(void *chip_info)
 {
@@ -10,10 +11,14 @@ static void mainboard_init(void *chip_info)
 	pads = variant_gpio_table(&num);
 	gpio_configure_pads(pads, num);
 }
+static void mainboard_dev_init(struct device *dev)
+{
+	mainboard_ec_init();
+}
 
 static void mainboard_enable(struct device *dev)
 {
-	/* TODO: Enable mainboard */
+	dev->ops->init = mainboard_dev_init;
 }
 
 struct chip_operations mainboard_ops = {
diff --git a/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/ec.h b/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/ec.h
new file mode 100644
index 0000000000..3c7fde5f54
--- /dev/null
+++ b/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/ec.h
@@ -0,0 +1,76 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef __BASEBOARD_EC_H__
+#define __BASEBOARD_EC_H__
+
+#include <ec/ec.h>
+#include <ec/google/chromeec/ec_commands.h>
+#include <baseboard/gpio.h>
+
+#define MAINBOARD_EC_SCI_EVENTS \
+	(EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_CLOSED)        |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_OPEN)          |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_CONNECTED)      |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_DISCONNECTED)   |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_LOW)       |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_CRITICAL)  |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY)           |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_STATUS)    |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_THERMAL_THRESHOLD) |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_THROTTLE_START)    |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_THROTTLE_STOP)     |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_CHARGER)       |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_MKBP)              |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_PD_MCU)            |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_MODE_CHANGE)       |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX))
+#define MAINBOARD_EC_SMI_EVENTS \
+	(EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_CLOSED))
+/* EC can wake from S5 with lid or power button */
+#define MAINBOARD_EC_S5_WAKE_EVENTS \
+	(EC_HOST_EVENT_MASK(EC_HOST_EVENT_LID_OPEN)     |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_POWER_BUTTON))
+/*
+ * EC can wake from S3/S0ix with:
+ * 1. Lid open
+ * 2. AC Connect/Disconnect
+ * 3. Power button
+ * 4. Key press
+ * 5. Mode change
+ */
+#define MAINBOARD_EC_S3_WAKE_EVENTS \
+	(MAINBOARD_EC_S5_WAKE_EVENTS |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_CONNECTED)    |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_AC_DISCONNECTED) |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_KEY_PRESSED)     |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_MODE_CHANGE))
+#define MAINBOARD_EC_S0IX_WAKE_EVENTS \
+	(MAINBOARD_EC_S3_WAKE_EVENTS |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_USB_MUX)         |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_HANG_DETECT))
+/* Log EC wake events plus EC shutdown events */
+#define MAINBOARD_EC_LOG_EVENTS \
+	(EC_HOST_EVENT_MASK(EC_HOST_EVENT_THERMAL_SHUTDOWN) |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_BATTERY_SHUTDOWN) |\
+	 EC_HOST_EVENT_MASK(EC_HOST_EVENT_PANIC))
+/*
+ * ACPI related definitions for ASL code.
+ */
+/* Enable EC backed ALS device in ACPI */
+#define EC_ENABLE_ALS_DEVICE
+/* Enable Keyboard Backlight */
+#define EC_ENABLE_KEYBOARD_BACKLIGHT
+/* Enable MKBP for buttons and switches */
+#define EC_ENABLE_MKBP_DEVICE
+/* Enable LID switch and provide wake pin for EC */
+#define EC_ENABLE_LID_SWITCH
+#define EC_ENABLE_WAKE_PIN      GPE_EC_WAKE
+/* Enable EC backed PD MCU device in ACPI */
+#define EC_ENABLE_PD_MCU_DEVICE
+#define SIO_EC_MEMMAP_ENABLE     /* EC Memory Map Resources */
+#define SIO_EC_HOST_ENABLE       /* EC Host Interface Resources */
+#define SIO_EC_ENABLE_PS2K       /* Enable PS/2 Keyboard */
+
+#define EC_ENABLE_SYNC_IRQ      /* Enable tight timestamp / wake support */
+
+#endif /* __BASEBOARD_EC_H__ */
diff --git a/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/gpio.h b/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/gpio.h
index a708db11ad..0011ebb6ed 100644
--- a/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/gpio.h
+++ b/src/mainboard/google/rex/variants/baseboard/rex/include/baseboard/gpio.h
@@ -6,4 +6,11 @@
 #include <soc/gpe.h>
 #include <soc/gpio.h>
 
+/* GPIO IRQ for tight timestamps / wake support */
+#define EC_SYNC_IRQ	0
+/* eSPI virtual wire reporting */
+#define EC_SCI_GPI	GPE0_ESPI
+/* EC wake is LAN_WAKE# which is a special DeepSX wake pin */
+#define GPE_EC_WAKE	GPE0_LAN_WAK
+
 #endif /* __BASEBOARD_GPIO_H__ */
diff --git a/src/mainboard/google/rex/variants/rex0/include/variant/ec.h b/src/mainboard/google/rex/variants/rex0/include/variant/ec.h
new file mode 100644
index 0000000000..4fc0622f15
--- /dev/null
+++ b/src/mainboard/google/rex/variants/rex0/include/variant/ec.h
@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#ifndef MAINBOARD_EC_H
+#define MAINBOARD_EC_H
+
+#include <baseboard/ec.h>
+
+#endif /* MAINBOARD_GPIO_H */
diff --git a/src/mainboard/google/rex/variants/rex0/include/variant/gpio.h b/src/mainboard/google/rex/variants/rex0/include/variant/gpio.h
index 27c87b3fe7..41c3798bc1 100644
--- a/src/mainboard/google/rex/variants/rex0/include/variant/gpio.h
+++ b/src/mainboard/google/rex/variants/rex0/include/variant/gpio.h
@@ -5,4 +5,6 @@
 
 #include <baseboard/gpio.h>
 
+/* TODO: Add GPIO as per rex board */
+
 #endif /* __MAINBOARD_GPIO_H__ */