TegraBootrom » History » Version 1
Denis 'GNUtoo' Carikli, 02/24/2020 02:33 AM
Move and adapt documentation from BootloadersFreedom
| 1 | 1 | Denis 'GNUtoo' Carikli | h1. TegraBootrom |
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| 3 | h2. General status |
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| 5 | It's up to the device vendor to decide if the bootrom should enforce signature or not. |
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| 7 | Some devices and several development boards (like the Jetson boards) do not enforce code signature by default. |
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| 9 | h2. Fusee gelee |
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| 11 | When code signature is enforced, "fusee_gelee":https://github.com/Qyriad/fusee-launcher/blob/master/report/fusee_gelee.md can still enable to load unsigned code through USB, as it use a bug in the USB stack, it can only be used when booting through USB. |
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| 13 | The downside is that, to boot an unsigned and free software bootloader, you need either: |
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| 14 | * To use another computer with some free software tools to load the free bootloader into the device that has the Tegra SOC |
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| 15 | * To use an USB dongle when booting as mentioned in that "youtube video":https://www.youtube.com/watch?v=REx_qSTulJM |
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| 17 | h2. Beyond Fusee gelee |
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| 19 | After loading a free software bootloader through USB, it might be possible to patch the bootrom, as part of it ends up being in the fuse memory region. |
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| 21 | This is meant to fix bugs inside the bootrom, but we might also be able to use it to disable code signature completely. |