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3 changes: 3 additions & 0 deletions .gitignore
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macvdmtool
*.o
*.so
*.dylib
119 changes: 113 additions & 6 deletions README.md
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# Apple Silicon to Apple Silicon VDM tool

This tool lets you get a serial console on an Apple Silicon device and reboot it remotely, using only another Apple Silicon device running macOS and a standard Type C cable.
This tool lets you send common Apple VDM messages from an Apple Sillicon Mac. It can send messages to the T2 DFU port, the Apple M1 DFU port or any USB-C based iPad. Currently it requires the sending device to be M1 based and the "DFU" port, but it should be possible to use any port and work from an Intel Mac (they have the same USB-C port controller) with some additonal patching.

`dfu` and `reboot` are confirmed to work on iPad and T2. Serial can probably be adapted to work with checkra1n.

## Disclaimer

Expand All @@ -15,17 +17,122 @@ This is based on portions of [ThunderboltPatcher](https://github.com/osy/Thunder

Thanks to t8012.dev and mrarm for assistance with the VDM and Ace2 host interface commands.

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## Note about macOS 12

To have access to the serial console device on macOS Monterey (12), you need to disable the `AppleSerialShim` extension.

**Note:** This requires downgrading the system security and may cause problems with upgrades. Use it at your own risk!

Start by generating a new kernel cache, without the `AppleSerialShim` extension:

```
sudo kmutil create -n boot -a arm64e -B /Library/KernelCollections/kc.noshim.macho -V release -k /System/Library/Kernels/kernel.release.<soc> -r /System/Library/Extensions -r /System/Library/DriverExtensions -x $(kmutil inspect -V release --no-header | awk '!/AppleSerialShim/ { print " -b "$1; }')
```

Replace `<soc>` with `t8101` on M1 Macs and `t6000` on M1 Pro/Max Macs. If you’re unsure, `uname -v` and look at the end of the version string (`RELEASE_ARM64_<soc>`).

Then, enter 1TR:

1. Power off your Mac
2. Press and hold the Power button until the boot menu appears
3. Select “Options”, then (if necessary) select your macOS volume and enter your administrative password.

Select Utilities>Startup security and switch the macOS installation to reduced security. Exit Startup security.

Select Utilities>Terminal and install your custom kernel:

```
kmutil configure-boot -c /Volume/<volume>/Library/KernelCollections/kc.noshim.macho -C -v /Volume/<volume>
```

Replace `<volume>` with the name of your boot volume.

You can now reboot: macOS should start as normal, and the serial device `/dev/cu.debug-console` should be available.

To revert back to the default kernel, enter 1TR again, access Utilities>Startup security and switch to full or reduced security.
=======
The documentation of the ACE and its USB-PD VPDs is here https://blog.t8012.dev/ace-part-1/
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VDPs?

>>>>>>> b396565 (Added T2 and iPad data)
=======
The documentation of the ACE and its USB-PD VPDs is here https://blog.t8012.dev/ace-part-1/
>>>>>>> 239e733 (Added T2 and iPad data)

>>>>>>> 31c618f (README: Update for Monterey and new MBPs)
## Note about macOS 12

To have access to the serial console device on macOS Monterey (12), you need to disable the `AppleSerialShim` extension.

**Note:** This requires downgrading the system security and may cause problems with upgrades. Use it at your own risk!

Start by generating a new kernel cache, without the `AppleSerialShim` extension:

```
sudo kmutil create -n boot -a arm64e -B /Library/KernelCollections/kc.noshim.macho -V release -k /System/Library/Kernels/kernel.release.<soc> -r /System/Library/Extensions -r /System/Library/DriverExtensions -x $(kmutil inspect -V release --no-header | awk '!/AppleSerialShim/ { print " -b "$1; }')
```

Replace `<soc>` with `t8101` on M1 Macs and `t6000` on M1 Pro/Max Macs. If you’re unsure, `uname -v` and look at the end of the version string (`RELEASE_ARM64_<soc>`).

Then, enter 1TR:

1. Power off your Mac
2. Press and hold the Power button until the boot menu appears
3. Select “Options”, then (if necessary) select your macOS volume and enter your administrative password.

Select Utilities>Startup security and switch the macOS installation to reduced security. Exit Startup security.

Select Utilities>Terminal and install your custom kernel:

```
kmutil configure-boot -c /Volume/<volume>/Library/KernelCollections/kc.noshim.macho -C -v /Volume/<volume>
```

Replace `<volume>` with the name of your boot volume.

You can now reboot: macOS should start as normal, and the serial device `/dev/cu.debug-console` should be available.

To revert back to the default kernel, enter 1TR again, access Utilities>Startup security and switch to full or reduced security.

## Building

Install the XCode commandline tools and type `make`.

## Usage

Connect the two devices via their DFU ports. That's the rear port on MacBooks and the port nearest to the power plug on Mac Minis.

You need to use a *USB 3.0 compatible* (SuperSpeed) Type C cable. USB 2.0-only cables, including most cables meant for charging, will not work, as they do not have the required pins. Thunderbolt cables work too.

Run it as root (`sudo ./macvdmtool`).
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>>>>>>> 31c618f (README: Update for Monterey and new MBPs)
Connect the two devices via their DFU ports. That's:
- the rear port on MacBook Air and 13" MacBook Pro
- the port next to the MagSafe connector on the 14" and 16" MacBook Pro
- the port nearest to the power plug on Mac Mini
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Connect the two devices via their DFU ports. That's the furthest left port on M1 MacBooks, the closest left port on the T2, and the only port on the iPad. See Apple's DFU recovery support articles to identify these ports on other models.
>>>>>>> b396565 (Added T2 and iPad data)
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Connect the two devices via their DFU ports. That's the furthest left port on M1 MacBooks, the closest left port on the T2, and the only port on the iPad. See Apple's DFU recovery support articles to identify these ports on other models.
>>>>>>> 239e733 (Added T2 and iPad data)
=======
Connect the two devices via their DFU ports. That's:
- the rear port on MacBook Air and 13" MacBook Pro (Apple M Series)
- the port next to the MagSafe connector on the 14" and 16" MacBook Pro
- the port nearest to the power plug on Mac Mini (Apple M Series)
- the closest (to the user) USB port on T2 based MacBooks
- the only port on the iPad / iPhone
>>>>>>> 567ee0e (README: Update for Monterey and new MBPs)
>>>>>>> 31c618f (README: Update for Monterey and new MBPs)

You need to use a *USB 3.0 compatible* (SuperSpeed) Type C cable. USB 2.0-only cables, including most cables meant for charging, will not work, as they do not have the required pins (USB CC1/CC2 where USB-PD are transmitted). Thunderbolt cables work too.
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This is not correct; the missing pins are SBU1/SBU2, which we use for serial. USB 2.0 cables do work for USB-PD commands like reboot, just not for serial.

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Honestly its missing both... but neither here nor there (it only ends up connecting D+/D- SS1/2 and VCC / GND on a 2.0 cable)

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No, a 2.0 cable will have a CC line. A cable without a CC line connected is nonconformant and a lot of things would break with it, including direction and orientation and PD negotiation. I think you're confusing CC with "SS" (not sure what that is, either SBU or SSTX/SSRX?)


Run it as root (`sudo ./macvdmtool`) as root privledge is required to open the needed IOKit IOService.

```
Usage: ./macvdmtool <command>
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