Is there a non-dual-boot bootloader for the ipod 6th gen?

[Frankenpod]

Was considering putting a >128gb drive in a 6th gen classic (one with the LBA28 limitation in the original firmware), and just trying to use it exclusively with rockbox.  The problem with that is that if it ever boots up in the original firmware it will probably (as I understand it) immediately corrupt the storage.  Is there a version of the bootloader available that disables the dual-boot facility, locking it to rockbox mode, so as to avoid that problem?
(It'll probably be a hard drive, not a flash mod, so don't need to worry about the rockbox/flash mod compatibility issue, but would still need to avoid accidentally using the original firmware)

OK, I found this thread, but to follow the instructions there I'd need a copy of the mks5lboot tool, and am not sure where to get that...

https://forums.rockbox.org/index.php?topic=51810.0

[7o9]

I believe precompiled versions of mks5lboot come with Rockbox Utility. Did you check that?

If you are not on Windows, instructions (including getting mks5lboot) are here https://files.freemyipod.org/~user890104/bootloader-ipodclassic.html

[Frankenpod]

For whatever reason, I don't seem to have that executable in the more recent versions of RB utility I have (only files in the folder are ipodpatcher.exe, rockboxutility.exe and sansapatcher.exe)...though I did just find one in the folder of an early version of the ipod-classic-specific installer still on my PC from 2017.  Would that be sufficient?  Anything changed in that particular utility since 2017?

[rockbox_dev123]

If you had searched thoroughly you might have found this:
http://forums.rockbox.org/index.php/topic,42520.0.html

...

Here is the .patch file I used when I made these modifications myself:

Code: [Select]

--- ipod6g.c 2019-05-13 23:17:17.212288000 +0100
+++ "ipod6g (copy 1).c" 2019-05-13 23:47:38.047876458 +0100
@@ -372,12 +372,13 @@
             btn = button_read_device();
         }
         /* Enter OF, diagmode and diskmode using ONB */
-        if ((btn == BUTTON_MENU)
+/*        if ((btn == BUTTON_MENU)
                 || (btn == (BUTTON_SELECT|BUTTON_LEFT))
                 || (btn == (BUTTON_SELECT|BUTTON_PLAY))) {
             fw = FW_APPLE;
             rc = kernel_launch_onb();
         }
+*/
     }
 
     lcd_init();
@@ -409,12 +410,13 @@
         filesystem_init();
 
         /* We wait until HDD spins up to check for hold button */
-        if (button_hold()) {
+/*        if (button_hold()) {
             fw = FW_APPLE;
             printf("Executing OF...");
             ata_sleepnow();
             rc = kernel_launch_onb();
         }
+*/
     }
 
     if (rc != 0) {

I have attached the binary bootloader I compiled some time ago (rename the fake jpg extension to .ipod):

bootloader-ipod6g.ipod: pre-compiled bootloader modified to prevent launching official firmware as this corrupts all disks > ~127GB (flash with # mk6gboot --bl-inst bootloader-ipod6g_modif.ipod )

[rockbox_dev123]

I would suggest flashing the modified bootloader here instead of using single boot mode for the following reasons:

I found out the hard way that booting into Apple's Disk mode via the instructions here:

Usage
Turning on the iPod

Unlock the HOLD switch, or press any button if already unlocked.
Turning off the iPod when running Rockbox

Hold down the PLAY button, until you see Shutting down...
Switching from Apple's firmware to Rockbox

Hold down MENU+SELECT, until the iPod reboots. Release them immediately after the screen goes black.
Switching from Rockbox to Apple's firmware

Turn off the iPod, then turn it on and immediately lock the HOLD switch.

- OR -

Turn off the iPod, then turn it on and immediately hold down MENU.
Entering Apple's Disk mode

Turn off the iPod. Power it on by holding down SELECT+PLAY, keep holding until Disk mode starts.
Entering Apple's Diagnostics mode

Turn off the iPod. Power it on by holding down SELECT+LEFT, keep holding until Diagnostics mode starts.
Entering Rockbox's Bootloader USB mode

Turn off the iPod. Power it on by holding down SELECT+RIGHT, keep holding until you see the USB Mode message.

Will also corrupt your disk...

After spending a few days to re-transfer my music...

I just tested installing a freshly recompiled stock bootloader in single mode via:

Code: [Select]

[foo@bar mks5lboot]$ sudo ./mks5lboot --bl-inst ./bootloader-ipod6g.ipod --single
mks5lboot Version ee15e45224-200125
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[INFO] Building DFU:
[INFO]  type:         BL installer (single)
[INFO]  BL size:      102592
[INFO]  DFU size:     110736
[INFO]  model name:   Classic 6G
[INFO]  platform:     ipod6g
[INFO]  RB name:      ip6g
[INFO]  RB num:       71
[INFO] libusb: found [05ac:1223] at bus 1, device 30, USB ver. 0200
[INFO] iPod Nano 3G / Classic, mode: DFU
[INFO] DFU image sent successfully (110736 bytes)
As suggested here.

I find that I can still boot into the Apple firmware via the HOLD switch and it prompts to "Connect to iTunes to restore" but this thankfully doesn't corrupt my disk.

I'm not going to attempt to boot into Apple's Disk mode as it seems that its still possible to dual boot after flashing in --single mode.

I suspect that it is not removing the OF partition whcih is the opposite of what is suggested by the README of mks5lboot (emphasis mine):

The single-boot installer writes the bootloader on the NOR with no previous check, the original Apple NOR boot is destroyed if it exists.

[rockbox_dev123]

I've given some context that is hopefully useful in the previous messages I quoted.

Another thing that you can do - without needing to reflash the bootloader - is just to delete or erase the partition that holds the OFW. This should be a simple way to prevent it from booting.

[Frankenpod]

I've given some context that is hopefully useful in the previous messages I quoted.

Another thing that you can do - without needing to reflash the bootloader - is just to delete or erase the partition that holds the OFW. This should be a simple way to prevent it from booting.

Thanks!

  Sounds promising - will give both methods a try.  Have a 6th gen logic board left over and a few 160gb drives from a 7.5gen, so either have to waste 20Gb of storage, or make it a rockbox-only device.
(Trying to finally consolidate the big box of mismatched spare parts I have into as many working devices as possible and chuck the irredeemably broken bits!)

[iPodVT]

Apologies if the info I'm seeking is already posted and I missed it.

Yesterday I successfully followed the video instructions [https://www.iflash.xyz/how-to-rockbox-installation-on-ipod-classic-using-new-bootloader/] for eliminating the Apple firmware and its LBA28 128GB limit with the 6th Gen Classic.  I finished with yesterday's dev build of Rockbox installed and was able to access the entire capacity of a 256GB SD card ('translated' to [edit] ~238GB) in an iFlash adapter.

Is it (still) true that corruption will occur in any/all of the following conditions:

1 - Boot with Lock Switch engaged?

2 - Boot with Menu Button held down?

3 - Boot with [edit] Select and Play Buttons held down?

4 - How about trying to boot into Diagnostic Mode?

Thanks.

PS - I added two edits above - my brain seems to be failing (fast)...

[rockbox_dev123]

Apologies if the info I'm seeking is already posted and I missed it.

Is it (still) true that corruption will occur in any/all of the following conditions:

1 - Boot with Lock Switch engaged?
2 - Boot with Menu Button held down?
3 - Boot with [edit] Select and Play Buttons held down?
4 - How about trying to boot into Diagnostic Mode?

Thanks.

PS - I added two edits above - my brain seems to be failing (fast)...

Regardless of whether you are using the stock bootloader  or my modified one. If any of the OFW boots then assume you will get a "corrupted" disk.

The trick to preserving your data without having to retransfer it all is to back up the partition table from rockbox and restore it again in the rockbox USB bootloader mode after the OFW rewrites it. You can do this with dd or sgdisk or numerous Linux utils. I recently recreated the partition table with fdisk after accidentally booting into the OFW on a CF modded iPod and was pleasantly surprised when all of the files re-appeared.