U-Boot - Revision history

User890104 at 23:02, 11 August 2026

2026-08-11T23:02:23Z

← Older revision		Revision as of 23:02, 11 August 2026
Line 91:		Line 91:
	== Known issues ==		== Known issues ==

	* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.		* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600. Also it looks like the system timer is running 2x or more slower.
	* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled~~. Also it looks like the timer is running 2x slower~~.		* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the time characters are garbled.
	* On [[Nano 5G]] it fails to boot using https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77. It's caused by a misaligned DT, which is checked here: https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77?file_path=scripts%2Fdtc%2Flibfdt%2Ffdt.c#line_b918a48ef_A25		* On [[Nano 5G]] it fails to boot using https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77. It's caused by a misaligned DT, which is checked here: https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77?file_path=scripts%2Fdtc%2Flibfdt%2Ffdt.c#line_b918a48ef_A25
	<pre>		<pre>

User890104 at 22:18, 11 August 2026

2026-08-11T22:18:20Z

← Older revision		Revision as of 22:18, 11 August 2026
Line 93:		Line 93:
	* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.		* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.
	* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.		* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.
	* On [[Nano 5G]] it ~~currently~~ fails to boot. It's caused by a misaligned DT, which is checked here: https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77?file_path=scripts%2Fdtc%2Flibfdt%2Ffdt.c#line_b918a48ef_A25		* On [[Nano 5G]] it fails to boot using https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77. It's caused by a misaligned DT, which is checked here: https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77?file_path=scripts%2Fdtc%2Flibfdt%2Ffdt.c#line_b918a48ef_A25
	<pre>		<pre>
	<debug_uart>		<debug_uart>

User890104 at 22:17, 11 August 2026

2026-08-11T22:17:15Z

← Older revision		Revision as of 22:17, 11 August 2026
Line 93:		Line 93:
	* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.		* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.
	* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.		* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.
	* On [[Nano 5G]] it currently fails to boot.		* On [[Nano 5G]] it currently fails to boot. It's caused by a misaligned DT, which is checked here: https://git.u-boot-project.org/u-boot/u-boot/-/commit/0535e46d55d7423094d8b553d704a0f7f678de77?file_path=scripts%2Fdtc%2Flibfdt%2Ffdt.c#line_b918a48ef_A25
	<pre>		<pre>
	<debug_uart>		<debug_uart>
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	### ERROR ### Please RESET the board ###		### ERROR ### Please RESET the board ###
	</pre>		</pre>
			* Out-of-tree building is broken in https://git.u-boot-project.org/u-boot/custodians/u-boot-stm/-/commit/bd3f9ee679b4d1456d0d3c261ab76788950e6096 because a relative path is used (srctree) instead of an absolute one (KBUILD_SRC).

	Your mileage may vary. Patches welcome.		Your mileage may vary. Patches welcome.

User890104 at 12:06, 11 August 2026

2026-08-11T12:06:40Z

← Older revision		Revision as of 12:06, 11 August 2026
Line 93:		Line 93:
	* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.		* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.
	* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.		* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.
			* On [[Nano 5G]] it currently fails to boot.
			<pre>
			<debug_uart>
			No valid device tree binary found at 0ac4b774
			initcall_run_f(): initcall fdtdec_setup() failed
			### ERROR ### Please RESET the board ###
			</pre>

	Your mileage may vary. Patches welcome.		Your mileage may vary. Patches welcome.

User890104 at 11:29, 11 August 2026

2026-08-11T11:29:34Z

← Older revision		Revision as of 11:29, 11 August 2026
Line 89:		Line 89:
	The bootrom of the S5L87xx SoCs is 50 KiB (0xc800 bytes). It is unencrypted and contains ARM executable code. It is read-only, hence the -ROM suffix.		The bootrom of the S5L87xx SoCs is 50 KiB (0xc800 bytes). It is unencrypted and contains ARM executable code. It is read-only, hence the -ROM suffix.

	== ~~Work in progress~~==		== Known issues ==

	~~You can run the~~ [[Nano 5G]] ~~image on a~~ [[~~Nano 4G~~]] and it ~~seems to be working at first glance~~.		* On [[Nano 3G]] and [[Classic 1G]] the UART interface is using an odd baudrate - 57600.
			* On [[Classic 1G]] sending UART commands to U-boot is very unstable and most of the characters are garbled. Also it looks like the timer is running 2x slower.

	Your mileage may vary. Patches welcome.		Your mileage may vary. Patches welcome.

User890104: add classic 6th gen

2026-08-11T11:11:48Z

add classic 6th gen

← Older revision		Revision as of 11:11, 11 August 2026
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	== U-Boot Port ==		== U-Boot Port ==

	We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]] ~~and~~ [[Nano 7G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.		We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]], [[Nano 7G]] and [[Classic 1G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.

	The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.		The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.
Line 18:		Line 18:
	$ make apple_n20_defconfig # iPod nano (6th generation)		$ make apple_n20_defconfig # iPod nano (6th generation)
	$ make apple_n31_defconfig # iPod nano (7th generation)		$ make apple_n31_defconfig # iPod nano (7th generation)
			$ make apple_n25_defconfig # iPod classic (6th generation)

	=== Building ===		=== Building ===
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	Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.		Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.

	==== [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]] ~~and~~ [[Nano 7G]] ====		==== [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]], [[Nano 7G]] and [[Classic_1G]] ====

	Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:		Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:
Line 210:		Line 211:
	Net: No ethernet found.		Net: No ethernet found.
	Hit any key to stop autoboot: 0		Hit any key to stop autoboot: 0
			</pre>
			=== [[Classic 1G]] ===
			<pre>
			<debug_uart>


			U-Boot 2026.10-rc2-00072-g3aa4be6d5553 (Aug 11 2026 - 12:40:25 +0300)

			CPU: Samsung S5L8702 (ARM926EJ-S)
			Model: Apple iPod classic (6th generation)
			DRAM: 64 MiB
			Core: 8 devices, 7 uclasses, devicetree: separate
			MMC:
			Loading Environment from nowhere... OK
			In: uart@3cc00000
			Out: uart@3cc00000
			Err: uart@3cc00000
			Net: No ethernet found.
			Hit any key to stop autoboot: 0
	</pre>		</pre>

User890104: add nano 4th

2026-08-10T17:11:30Z

add nano 4th

← Older revision		Revision as of 17:11, 10 August 2026
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	== U-Boot Port ==		== U-Boot Port ==

	We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.		We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.

	The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.		The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.
Line 14:		Line 14:
	$ make apple_n36_defconfig # iPod nano (2nd generation)		$ make apple_n36_defconfig # iPod nano (2nd generation)
	$ make apple_n46_defconfig # iPod nano (3rd generation)		$ make apple_n46_defconfig # iPod nano (3rd generation)
			$ make apple_n58_defconfig # iPod nano (4th generation)
	$ make apple_n33_defconfig # iPod nano (5th generation)		$ make apple_n33_defconfig # iPod nano (5th generation)
	$ make apple_n20_defconfig # iPod nano (6th generation)		$ make apple_n20_defconfig # iPod nano (6th generation)
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	Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.		Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.

	==== [[Nano 3G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]] ====		==== [[Nano 3G]], [[Nano 4G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]] ====

	Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:		Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:
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	DRAM: 32 MiB		DRAM: 32 MiB
	LCD: Type 38b3 (0)		LCD: Type 38b3 (0)
			Core: 8 devices, 7 uclasses, devicetree: separate
			MMC:
			Loading Environment from nowhere... OK
			In: uart@3cc00000
			Out: uart@3cc00000
			Err: uart@3cc00000
			Net: No ethernet found.
			Hit any key to stop autoboot: 0
			</pre>
			=== [[Nano 4G]] ===
			<pre>
			<debug_uart>


			U-Boot 2025.07-rc4-g9eb882bc879d (Aug 10 2026 - 20:03:21 +0300)

			CPU: Samsung S5L8720 (ARM1176JZF-S)
			Model: Apple iPod nano (4th generation)
			DRAM: 32 MiB
	Core: 8 devices, 7 uclasses, devicetree: separate		Core: 8 devices, 7 uclasses, devicetree: separate
	MMC:		MMC:

User890104: bootrom dumping

2026-08-09T22:06:58Z

bootrom dumping

← Older revision		Revision as of 22:06, 9 August 2026
Line 61:		Line 61:

	The command may fail the first time, retry one or two times before asking for help.		The command may fail the first time, retry one or two times before asking for help.

			=== Verifying if U-boot is running ===

			After executing the exploit, check if U-boot started successfully. It should expose a DFU interface that provides 2 altsettings: firmware (0) and bootrom (1). The first can be used to boot the next firmware (U-boot, Linux, Rockbox, etc.), the second one can be used to dump the device's bootrom for further inspection.

			$ dfu-util --device 05ac:8007 --list

	=== Pushing an image to U-boot ===		=== Pushing an image to U-boot ===

	~~When successfully started,~~ U-Boot ~~will then enumerate as yet another DFU device, this time ready~~ to ~~receive an~~ U-~~Boot compatible image. You can load an image~~ using dfu-util:		You can send an U-Boot compatible image to the firmware endpoint of U-boot using dfu-util:

	$ dfu-util --device 05ac:8007 --alt 0 --download foo		$ dfu-util --device 05ac:8007 --alt firmware --download foo
	$ dfu-util --device 05ac:8007 --detach		$ dfu-util --device 05ac:8007 --detach

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	Make sure your user can access the raw USB device, add udev rules (recommended) or run with root (not recommended).		Make sure your user can access the raw USB device, add udev rules (recommended) or run with root (not recommended).

			=== Dumping the BootROM ===

			You can dump the bootrom from the device using dfu-util. It can be used for reverse-engineering and debugging.

			$ dfu-util --device 05ac:8007 --alt bootrom --upload bootrom.bin

			The bootrom of the S5L87xx SoCs is 50 KiB (0xc800 bytes). It is unencrypted and contains ARM executable code. It is read-only, hence the -ROM suffix.

	== Work in progress==		== Work in progress==

User890104: /* Pushing an image to U-boot */

2026-08-09T21:57:07Z

Pushing an image to U-boot

← Older revision		Revision as of 21:57, 9 August 2026
Line 66:		Line 66:
	When successfully started, U-Boot will then enumerate as yet another DFU device, this time ready to receive an U-Boot compatible image. You can load an image using dfu-util:		When successfully started, U-Boot will then enumerate as yet another DFU device, this time ready to receive an U-Boot compatible image. You can load an image using dfu-util:

	$ dfu-util --device 05ac:8007 --download foo		$ dfu-util --device 05ac:8007 --alt 0 --download foo
	$ dfu-util --device 05ac:8007 --detach		$ dfu-util --device 05ac:8007 --detach

User890104: Add Nano 6G

2026-08-09T21:56:41Z

Add Nano 6G

← Older revision		Revision as of 21:56, 9 August 2026
Line 1:		Line 1:
	== U-Boot Port ==		== U-Boot Port ==

	We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 5G]] and [[Nano 7G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.		We've been working on an experimental U-Boot port for the [[Nano 2G]], [[Nano 3G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]]. It can be started using [[wInd3x]] and will start up a CDC-ACM serial console over USB for debugging purposes. Currently it has no storage driver.

	The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.		The current port expects to be loaded in place of [[OSOS]], eg. by packaging it into an [[IMG1]] and sending it to [[WTF]]. This is what [[wInd3x]] does. This way, U-Boot does not have to do any of the 'annoying' early boot stuff like bringing up DRAM.
Line 15:		Line 15:
	$ make apple_n46_defconfig # iPod nano (3rd generation)		$ make apple_n46_defconfig # iPod nano (3rd generation)
	$ make apple_n33_defconfig # iPod nano (5th generation)		$ make apple_n33_defconfig # iPod nano (5th generation)
			$ make apple_n20_defconfig # iPod nano (6th generation)
	$ make apple_n31_defconfig # iPod nano (7th generation)		$ make apple_n31_defconfig # iPod nano (7th generation)

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	Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.		Upload the file to your iPod. Run Rockbox, go to File Manager, find the u-boot.ipod file and select it.

	==== [[Nano 3G]], [[Nano 5G]] and [[Nano 7G]] ====		==== [[Nano 3G]], [[Nano 5G]], [[Nano 6G]] and [[Nano 7G]] ====

	Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:		Connect your iPod in [[Modes\|DFU Mode]] and use [[wInd3x]] to start U-Boot:
Line 75:		Line 76:

	You can run the [[Nano 5G]] image on a [[Nano 4G]] and it seems to be working at first glance.		You can run the [[Nano 5G]] image on a [[Nano 4G]] and it seems to be working at first glance.

	You can run the [[Nano 5G]] image on a [[Nano 6G]], but if you don't stop the countdown before auto-booting, it gets stuck since the timer which is used to measure how much a second takes is not initialized properly. You can flood the UART console with key presses just while U-boot is printing the messages to skip the auto-boot prompt entiery and get dropped into a U-boot console.

	Your mileage may vary. Patches welcome.		Your mileage may vary. Patches welcome.
Line 131:		Line 130:
	DRAM: 64 MiB		DRAM: 64 MiB
	LCD: Type 38b3 (0)		LCD: Type 38b3 (0)
			Core: 8 devices, 7 uclasses, devicetree: separate
			MMC:
			Loading Environment from nowhere... OK
			In: uart@3cc00000
			Out: uart@3cc00000
			Err: uart@3cc00000
			Net: No ethernet found.
			Hit any key to stop autoboot: 0
			</pre>
			=== [[Nano 6G]] ===
			<pre>
			<debug_uart>


			U-Boot 2025.07-rc4-g5a3badf00973 (Aug 09 2026 - 17:57:17 +0300)

			CPU: Samsung S5L8723 (ARM1176JZF-S)
			Model: Apple iPod nano (6th generation)
			DRAM: 64 MiB
	Core: 8 devices, 7 uclasses, devicetree: separate		Core: 8 devices, 7 uclasses, devicetree: separate
	MMC:		MMC: