From f00ce5ca9b118df6fb318f63112a078dd671ea41 Mon Sep 17 00:00:00 2001
From: Hector Palacios <hector.palacios@digi.com>
Date: Mon, 23 Aug 2021 13:26:24 +0200
Subject: [PATCH] u-boot-dey: add support for dualboot to boot scripts

The support for dualboot was integrated on meta-digi-dualboot layer, but it
really depends only on environment variable 'dualboot' so we'd better
integrate the support on the scripts in meta-digi, to avoid synchonization
problems between both layers.
This also allows to be able to easily enable dualboot in U-Boot with the
variable, without needing to update the script on the linux partition.

Signed-off-by: Hector Palacios <hector.palacios@digi.com>
---
 .../u-boot/u-boot-dey/ccimx6qpsbc/boot.txt    | 75 +++++++++++++---
 .../u-boot/u-boot-dey/ccimx6sbc/boot.txt      | 75 +++++++++++++---
 .../u-boot/u-boot-dey/ccimx6ulsbc/boot.txt    | 42 ++++++++-
 .../u-boot-dey/ccimx6ulstarter/boot.txt       | 42 ++++++++-
 .../u-boot/u-boot-dey/ccimx8mm-dvk/boot.txt   | 88 ++++++++++++++++---
 .../u-boot/u-boot-dey/ccimx8mn-dvk/boot.txt   | 88 ++++++++++++++++---
 .../u-boot-dey/ccimx8x-sbc-express/boot.txt   | 83 ++++++++++++++---
 .../u-boot-dey/ccimx8x-sbc-pro/boot.txt       | 83 ++++++++++++++---
 8 files changed, 496 insertions(+), 80 deletions(-)

diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6qpsbc/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6qpsbc/boot.txt
index 2ae28ea4a..5dedaa36d 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6qpsbc/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6qpsbc/boot.txt
@@ -25,19 +25,70 @@ else
 	fi
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_a_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6sbc/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6sbc/boot.txt
index e15593d2c..12b927abd 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6sbc/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6sbc/boot.txt
@@ -53,19 +53,70 @@ else
 	fi
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_a_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulsbc/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulsbc/boot.txt
index 03b3f7929..b3ddefaf9 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulsbc/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulsbc/boot.txt
@@ -37,11 +37,45 @@ else
 	fi
 fi
 
-if test "${mtdbootpart}" = "recovery"; then
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${mtdbootpart}" = "linux_a"; then
+				setenv mtdbootpart linux_b
+				setenv mtdlinuxindex ${mtdlinux_b_index}
+				setenv mtdrootfsindex ${mtdrootfs_b_index}
+			else
+				setenv mtdbootpart linux_a
+				setenv mtdlinuxindex ${mtdlinux_a_index}
+				setenv mtdrootfsindex ${mtdrootfs_a_index}
+			fi
+			setenv active_system ${mtdbootpart}
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			setenv mtdbootpart ${active_system}
+			setenv mtdlinuxindex ${mtdlinux_a_index}
+			setenv mtdrootfsindex ${mtdrootfs_a_index}
+		else
+			echo "Booting from system B"
+			setenv mtdbootpart ${active_system}
+			setenv mtdlinuxindex ${mtdlinux_b_index}
+			setenv mtdrootfsindex ${mtdrootfs_b_index}
+		fi
+	fi
 else
-	true
+	if test "${mtdbootpart}" = "recovery"; then
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		true
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux nand ${mtdbootpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulstarter/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulstarter/boot.txt
index 31825889d..84da4dfde 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulstarter/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx6ulstarter/boot.txt
@@ -37,11 +37,45 @@ else
 	fi
 fi
 
-if test "${mtdbootpart}" = "recovery"; then
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${mtdbootpart}" = "linux_a"; then
+				setenv mtdbootpart linux_b
+				setenv mtdlinuxindex ${mtdlinux_b_index}
+				setenv mtdrootfsindex ${mtdrootfs_b_index}
+			else
+				setenv mtdbootpart linux_a
+				setenv mtdlinuxindex ${mtdlinux_a_index}
+				setenv mtdrootfsindex ${mtdrootfs_a_index}
+			fi
+			setenv active_system ${mtdbootpart}
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			setenv mtdbootpart ${active_system}
+			setenv mtdlinuxindex ${mtdlinux_a_index}
+			setenv mtdrootfsindex ${mtdrootfs_a_index}
+		else
+			echo "Booting from system B"
+			setenv mtdbootpart ${active_system}
+			setenv mtdlinuxindex ${mtdlinux_b_index}
+			setenv mtdrootfsindex ${mtdrootfs_b_index}
+		fi
+	fi
 else
-	true
+	if test "${mtdbootpart}" = "recovery"; then
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		true
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux nand ${mtdbootpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mm-dvk/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mm-dvk/boot.txt
index ff9e9e163..1513df9e9 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mm-dvk/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mm-dvk/boot.txt
@@ -6,6 +6,19 @@
 setenv ORIG_overlays ${overlays}
 setenv ORIG_extra_bootargs ${extra_bootargs}
 
+# Set SOC type to "imx8mm" if not already defined by U-Boot
+if test ! -n "${soc_type}"; then
+	setenv soc_type "imx8mm"
+fi
+
+# Reset overlays when using dualboot mode, because we need to
+# save the environment in case of an installation fall back.
+if test "${dual_boot}" = "yes"; then
+        if test -n "${overlays}"; then
+                setenv overlays
+        fi
+fi
+
 #
 # Determine overlays to apply depending on the hardware capabilities
 # described by the HWID, SOM version, and carrier board version.
@@ -28,19 +41,70 @@ if test -n "${module_ram}"; then
 	fi
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_a_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mn-dvk/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mn-dvk/boot.txt
index 38530dcaf..7b7df5917 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mn-dvk/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8mn-dvk/boot.txt
@@ -6,6 +6,19 @@
 setenv ORIG_overlays ${overlays}
 setenv ORIG_extra_bootargs ${extra_bootargs}
 
+# Set SOC type to "imx8mn" if not already defined by U-Boot
+if test ! -n "${soc_type}"; then
+	setenv soc_type "imx8mn"
+fi
+
+# Reset overlays when using dualboot mode, because we need to
+# save the environment in case of an installation fall back.
+if test "${dual_boot}" = "yes"; then
+        if test -n "${overlays}"; then
+                setenv overlays
+        fi
+fi
+
 #
 # Determine overlays to apply depending on the hardware capabilities
 # described by the HWID, SOM version, and carrier board version.
@@ -37,19 +50,70 @@ if test "${board_version}" -lt "3"; then
 	setenv overlays _ov_board_v1-v2_ccimx8mn-dvk.dtbo,${overlays}
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-express/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-express/boot.txt
index 278914bcd..b99b3378b 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-express/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-express/boot.txt
@@ -11,6 +11,14 @@ if test ! -n "${soc_type}"; then
 	setenv soc_type "imx8qxp"
 fi
 
+# Reset overlays when using dualboot mode, because we need to
+# save the environment in case of an installation fall back.
+if test "${dual_boot}" = "yes"; then
+	if test -n "${overlays}"; then
+		setenv overlays
+	fi
+fi
+
 #
 # Determine overlays to apply depending on the hardware capabilities
 # described by the HWID, SOM version, and carrier board version.
@@ -45,19 +53,70 @@ if test "${soc_type}" = "imx8qxp"; then
 	setenv overlays _ov_som_quad_ccimx8x.dtbo,${overlays}
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_a_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}
diff --git a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-pro/boot.txt b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-pro/boot.txt
index 481c8cc2d..759308337 100644
--- a/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-pro/boot.txt
+++ b/meta-digi-arm/recipes-bsp/u-boot/u-boot-dey/ccimx8x-sbc-pro/boot.txt
@@ -11,6 +11,14 @@ if test ! -n "${soc_type}"; then
 	setenv soc_type "imx8qxp"
 fi
 
+# Reset overlays when using dualboot mode, because we need to
+# save the environment in case of an installation fall back.
+if test "${dual_boot}" = "yes"; then
+	if test -n "${overlays}"; then
+		setenv overlays
+	fi
+fi
+
 #
 # Determine overlays to apply depending on the hardware capabilities
 # described by the HWID, SOM version, and carrier board version.
@@ -50,19 +58,70 @@ if test "${board_version}" -le "3"; then
 	setenv overlays _ov_board_v1-v3_ccimx8x-sbc-pro.dtbo,${overlays}
 fi
 
-# Get the UUID of the configured boot partition.
-part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
-# Check the boot source.
-if test "${bootpart}" = "${part1_uuid}"; then
-	# We are booting from the eMMC using 'linux'.
-	true
-elif test "${bootpart}" = "${part2_uuid}"; then
-	# We are booting from the eMMC using 'recovery'.
-	setenv boot_initrd true
-	setenv initrd_file uramdisk-recovery.img
+# Dual boot update verification
+if test "${dualboot}" = "yes"; then
+	if test "${upgrade_available}" = "1"; then
+		echo "Update detected; Booting new system (try ${bootcount})"
+		if test "${bootcount}" = "${bootlimit}"; then
+			echo "## Update failed; Rolling back to previous version."
+			if test "${active_system}" = "linux_a"; then
+				part number mmc ${mmcbootdev} linux_b pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_b_index
+				part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+				# Save the rootfs_b UUID into mmcroot_b
+				part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+				setenv mmcroot PARTUUID=${mmcroot_b}
+				setenv active_system linux_b
+			else
+				part number mmc ${mmcbootdev} linux_a pi
+				setenv mmcpart ${pi}
+				# Save the partition index on variable rootfs_a_index
+				part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+				# Save the rootfs_a UUID into mmcroot_a
+				part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+				setenv mmcroot PARTUUID=${mmcroot_a}
+				setenv active_system linux_a
+			fi
+			setenv upgrade_available
+			saveenv
+		fi
+	else
+		if test "${active_system}" = "linux_a"; then
+			echo "Booting from system A"
+			part number mmc ${mmcbootdev} linux_a pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_a_index
+			part number mmc ${mmcbootdev} rootfs_a rootfs_a_index
+			# Save the rootfs_a UUID into mmcroot_a
+			part uuid mmc ${mmcbootdev}:${rootfs_a_index} mmcroot_a
+			setenv mmcroot PARTUUID=${mmcroot_a}
+		else
+			echo "Booting from system B"
+			part number mmc ${mmcbootdev} linux_b pi
+			setenv mmcpart ${pi}
+			# Save the partition index on variable rootfs_b_index
+			part number mmc ${mmcbootdev} rootfs_b rootfs_b_index
+			# Save the rootfs_b UUID into mmcroot_b
+			part uuid mmc ${mmcbootdev}:${rootfs_b_index} mmcroot_b
+			setenv mmcroot PARTUUID=${mmcroot_b}
+		fi
+	fi
 else
-	# We are booting from the SD card.
-	setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	# Get the UUID of the configured boot partition.
+	part uuid mmc ${mmcbootdev}:${mmcpart} bootpart
+	# Check the boot source.
+	if test "${bootpart}" = "${part1_uuid}"; then
+		# We are booting from the eMMC using 'linux'.
+		true
+	elif test "${bootpart}" = "${part2_uuid}"; then
+		# We are booting from the eMMC using 'recovery'.
+		setenv boot_initrd true
+		setenv initrd_file uramdisk-recovery.img
+	else
+		# We are booting from the SD card.
+		setenv mmcroot /dev/mmcblk${mmcbootdev}p2
+	fi
 fi
 setenv extra_bootargs fbcon=logo-pos:center ${extra_bootargs}
 dboot linux mmc ${mmcbootdev}:${mmcpart}