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DRDR

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Jul 23, 2008
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I can confirm, that the OWC Thunderbolt 4 Hub does not work with the trashcan Mac Pro using an Apple TB3 adapter. I only got it to work as an USB 2.0 hub and only after booting it plugged in.

Does anybody know, what technical limitations are in play here? I am just curious what feature set they are using for their hub.
 
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I don't think there are any technical limitations except software support which Apple could easily add.

Did you try Big Sur? The dock has limited support in Catalina.

Even with Catalina, you should have been able to get USB 3.1 Gen 2 support (but I'm not sure since I no longer have a Thunderbolt 2 Mac to test).

I did some testing with Catalina and Big Sur with a Thunderbolt 3 Mac:
https://forums.macrumors.com/thread...ts-and-four-usb-a-ports.2283180/post-29718129
 
The observed results were on Big Sur. It does not work on a MP 6,1
 
@cynicalmoose said it worked with a late 2015 5k iMac
https://forums.macrumors.com/threads/thunderbolt-3-m-2-nvme-ssd-enclosures.2027925/post-29480659
so I don't know why it wouldn't work with a Mac Pro 2013.

Did you try all 6 Thunderbolt 2 ports?

There is nothing between the OWC Thunderbolt Hub and the Mac Pro 2013 except the Apple Thunderbolt 3 to Thunderbolt 2 adapter?

If you got USB 2.0 working, then USB 3.1 Gen 2 must also work since both the USB 2.0 hub and 3.1 gen 2 hub are connected to the same controller in the OWC Thunderbolt 4 Hub.
 
I did not try all ports but I only used the TB3-TB-Adapter. USB only worked sometimes and only with 2.0 speed. I tested it with a Samsung T7
 
I did not try all ports but I only used the TB3-TB-Adapter. USB only worked sometimes and only with 2.0 speed. I tested it with a Samsung T7
Have you tested the TB4 dock again recently with MP6,1? I'm curious if there's been any change in your results. I'd like to get the dock as it has the most connectors I need, but not if its throttled at USB2 speeds.
 
As I understood it, the TB4 hub is only compatible with USB-C and Thunderbolt 3 - not via Thunderbolt 2 (even with an adapter)....
 
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They do at least make it clear in their advertising that it's only for Macs with TB3 ports.

Though I've managed to use the older TB3 dock with 2011 Macs with TB1 and can even boot Windows from one of their drives that they claim doesn't support booting into Windows.

If your Mac doesn't have TB3 ports I'd get one of the older docks whilst they are still available if you need a dock.
 
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Looks like the Caldigit Ts3 plus is the best option perhaps.
Anyone have experience with MP6,1 and an OWC TB3 14-port dock? Might be able to find a used one for half the cost of a used CalDigit.
 
I use the OWC TB3 dock with the mid-2011 iMac and mid-2011 Mac Mini (I have two docks). Booting off TB3 the performance is a little faster than single internal SATA III SSD would be even though the TB3 drive is throttled by the TB(1) port on the 2011.

I assume it should work with any Mac with TB provided it is running new enough macOS.
 
Hi everyone, new to the forum...and for this thread alone!

I have a late 2013 Macbook Pro 13" (model 11,2) with 2 x thunderbolt 2 ports. I'm running Big Sur 11.6.7. One T2 port is a display out to my Dell 27" monitor (mini DisplayPort to DisplayPort) and the other T2 port I hooked up the OWC Thunderbolt 4 dock (not hub, but it shouldn't matter right?) with an Apple T3->T2 adaptor and an Apple 0.5m T2 cable (male-male).

This setup has been successful. Initial plug-and-play wasn't, but after restarting / booting up with this arrangement in place everything seems to have been recognised appropriately and functioning properly.

See screenshot of the system report showing what has been recognised as what. The OWC dock is recognised as a USB 3.2 device at up to 10Gb/s.

Note 1: Connecting my Mac to the dock via USB-C to USB-A cable (in plug-and-play fashion) worked, but as the OP mentioned the OWC was recognised as a USB 2.0 hub.

Note 2: I did try connecting my external monitor to one of the T4 ports on the OWC dock via USB-C -> DisplayPort cable (Comsol brand), but the result wasn't workable. It took about a minute or 2 to acknowledge any signal between the dock and the monitor. Then all of a sudden the monitor flicked on with the extended screen for a second and then off. It continued to flick on and off throughout and didn't resolve. I'll try again and see if it will work. It's not a dealbreaker, as I don't use any other T2 devices so the 2nd T2 port on my Mac can always be used for my external monitor.
 

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Hi everyone, new to the forum...and for this thread alone!

I have a late 2013 Macbook Pro 13" (model 11,2) with 2 x thunderbolt 2 ports. I'm running Big Sur 11.6.7. One T2 port is a display out to my Dell 27" monitor (mini DisplayPort to DisplayPort) and the other T2 port I hooked up the OWC Thunderbolt 4 dock (not hub, but it shouldn't matter right?) with an Apple T3->T2 adaptor and an Apple 0.5m T2 cable (male-male).

This setup has been successful. Initial plug-and-play wasn't, but after restarting / booting up with this arrangement in place everything seems to have been recognised appropriately and functioning properly.

See screenshot of the system report showing what has been recognised as what. The OWC dock is recognised as a USB 3.2 device at up to 10Gb/s.

Note 1: Connecting my Mac to the dock via USB-C to USB-A cable (in plug-and-play fashion) worked, but as the OP mentioned the OWC was recognised as a USB 2.0 hub.

Note 2: I did try connecting my external monitor to one of the T4 ports on the OWC dock via USB-C -> DisplayPort cable (Comsol brand), but the result wasn't workable. It took about a minute or 2 to acknowledge any signal between the dock and the monitor. Then all of a sudden the monitor flicked on with the extended screen for a second and then off. It continued to flick on and off throughout and didn't resolve. I'll try again and see if it will work. It's not a dealbreaker, as I don't use any other T2 devices so the 2nd T2 port on my Mac can always be used for my external monitor.
What does the Thunderbolt tab show in System Information.app?
It may be that EFI Thunderbolt driver connects the Thunderbolt devices if macOS can't which is why it might work if it's connected before boot (This is true if you want to use a Thunderbolt 4 hub with Catalina).
 
A dock is different than the TB4 hub. A dock only has one uplink TB4 port while a hub is having more then one uplink. In my understanding such TB4 docks are the same as TB3 docks and not using TB4 features for the non display things.

I did not do any further testing because I sold the MP 6,1 and got a Studio.
 
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A dock is different than the TB4 hub. A dock only has one uplink TB4 port while a hub is having more then one uplink. In my understanding such TB4 docks are the same as TB3 docks and not using TB4 features for the non display things.

I did not do any further testing because I sold the MP 6,1 and got a Studio.
A Thunderbolt 4 dock and a Thunderbolt 4 hub are basically the same. They both have one upstream Thunderbolt port to the host and three downstream Thunderbolt ports to connect more Thunderbolt devices or USB devices or DisplayPort devices. A Thunderbolt 4 dock has additional USB hubs and USB adapters inside compared to a Thunderbolt 4 hub. The only Thunderbolt 4 feature that a Thunderbolt 3 dock doesn't have is tunnelling USB which isn't really a feature since USB can be done with tunnelled PCIe to the Thunderbolt device's USB controller. USB tunnelling bypasses the USB controller of the Thunderbolt device and uses only the USB controller of the host so all the USB devices in the Thunderbolt 4 chain would be limited to a single 10 Gbps connection (the Thunderbolt 4 devices behave as USB hubs when USB tunnelling is used). Tunnelled PCIe is better because each USB controller is separate - there's a 22 Gbps PCIe limit over Thunderbolt which you can fill with USB only when PCIe tunnelling is used.
 
A dock is different than the TB4 hub. A dock only has one uplink TB4 port while a hub is having more then one uplink. In my understanding such TB4 docks are the same as TB3 docks and not using TB4 features for the non display things.

I did not do any further testing because I sold the MP 6,1 and got a Studio.
What does the Thunderbolt tab show in System Information.app?
It may be that EFI Thunderbolt driver connects the Thunderbolt devices if macOS can't which is why it might work if it's connected before boot (This is true if you want to use a Thunderbolt 4 hub with Catalina).
Hey

Took another screenshot of the Thunderbolt tab. 'Nothing' connected according to this.

Well done on purchasing the Studio!
 

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Took another screenshot of the Thunderbolt tab. 'Nothing' connected according to this.
OK, so it's not detecting it as Thunderbolt. Check the PCI tab for any PCIe devices that might be part of the Thunderbolt hub. Actually, your first USB screenshot shows the PCIe USB controller of the Thunderbolt hub. It uses the AppleUSBXHCITR driver where XHCI is the controller type and TR stands for Titan Ridge even though the Thunderbolt controller is Goshen Ridge. The PCI Vendor ID and Product ID are 8086:0b27 which shows that it's Goshen Ridge
https://pci-ids.ucw.cz/read/PC/8086/0b27

So, while macOS doesn't support hot swap of Thunderbolt 4 devices on Thunderbolt 2 Macs, the EFI driver can initiate PCIe tunnelling successfully before boot which should make the hub useable after boot in macOS or any other OS as long as you don't disconnect the device or enter sleep mode.
 
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@joevt I can only give you one thumbs up here but would give you a 1000.
It would have never crossed my mind to connect the Thunderbolt 4 dock before boot.
I can confirm the Mac Pro 6,1 works with Thunderbolt 4 docks.
I am using the Apple Thunderbolt 2 cable and TB3 to TB2 dongle with the Satechi TB4 dock.

Screen Shot 2022-08-19 at 22.21.51.pngScreen Shot 2022-08-19 at 22.22.50.pngScreen Shot 2022-08-19 at 22.23.24.pngScreen Shot 2022-08-19 at 22.23.43.png
 
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I can confirm, that the OWC Thunderbolt 4 Hub does not work with the trashcan Mac Pro using an Apple TB3 adapter. I only got it to work as an USB 2.0 hub and only after booting it plugged in.

Does anybody know, what technical limitations are in play here? I am just curious what feature set they are using for their hub.
The hub, or any other TB3 device, will only work with that TB2/TB3 adapter if it is SELF powered. In other words, both sides of the adapter have to have their own power....
 
I can confirm the Mac Pro 6,1 works with Thunderbolt 4 docks.
I was able to get a "connection" but performance is not TB2 20 Gbps speed.

I have an Apple TB3 to TB2 adapter, OWC TB4 Hub and a TB4 SSD enclosure. Connecting them to the MP 6,1 without a reboot results in no enumeration. Rebooting the MP does cause a "partial" enumeration. As @joevt pointed out earlier, the PCIe tunnel enumerates so I see the NVMe controller of the SSD connected to the PCIe bus. The NVMe controller enumerates with a link width of x4 and a link speed of 8 GT/s which is expected for the JHL 7440 which has a PCIe Gen 3 bus which is the TB controller within the SSD enclosure. However, there is no Thunderbolt enumeration so I cannot see either of the Hub, the adapter, the TB2 cable or the TB4 cable. So, there is no way to tell from enumeration what the link speed is between the MP and the hub or the hub and the enclosure. The Blackmagic result suggests the link speed is only 10 Gbps. Finally, the SSD volumes that were mounted before going to sleep were all ejected when the computer woke up.

You can get a connection to a TB3 device that has a PCIe endpoint, but it is likely not an intended and supported use case for the Apple adapter.

So, my conclusion is that the Apple adapter is not very useful when used with a TB or TB2 Mac. I think it is intended to ONLY be used with TB2 devices and the suggestion that it is "bidirectional" is misleading. Apple's own overview suggests the adapter can be used with a dock:
The Thunderbolt 3 (USB-C) to Thunderbolt 2 Adapter lets you connect Thunderbolt and Thunderbolt 2 devices — such as external hard drives and Thunderbolt docks — to any of the Thunderbolt 3 (USB-C) / USB 4 ports on your Mac.

But it is the last part of the sentence that I think spells out the limitation: to any of the Thunderbolt 3 (USB-C) / USB 4 ports on your Mac. So, the adapter supports connecting a TB2 dock to a TB3 Mac but does not support connecting a TB3 dock to a TB2 Mac.


Screen Shot 2023-04-06 at 8.24.37 PM.png
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Screen Shot 2023-04-06 at 8.25.06 PM.png
DiskSpeedTest - Samsung 980 PRO - INDMEM U4001 - OWC TB HUB - APPLE TB3-TB2 ADAPTER - MP6.1.png
 
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I was able to get a "connection" but performance is not TB2 20 Gbps speed.

I have an Apple TB3 to TB2 adapter, OWC TB4 Hub and a TB4 SSD enclosure. Connecting them to the MP 6,1 without a reboot results in no enumeration. Rebooting the MP does cause a "partial" enumeration. As @joevt pointed out earlier, the PCIe tunnel enumerates so I see the NVMe controller of the SSD connected to the PCIe bus. The NVMe controller enumerates with a link width of x4 and a link speed of 8 GT/s which is expected for the JHL 7440 which has a PCIe Gen 3 bus which is the TB controller within the SSD enclosure. However, there is no Thunderbolt enumeration so I cannot see either of the Hub, the adapter, the TB2 cable or the TB4 cable. So, there is no way to tell from enumeration what the link speed is between the MP and the hub or the hub and the enclosure. The Blackmagic result suggests the link speed is only 10 Gbps. Finally, the SSD volumes that were mounted before going to sleep were all ejected when the computer woke up.

You can get a connection to a TB3 device that has a PCIe endpoint, but it is likely not an intended and supported use case for the Apple adapter.

So, my conclusion is that the Apple adapter is not very useful when used with a TB or TB2 Mac. I think it is intended to ONLY be used with TB2 devices and the suggestion that it is "bidirectional" is misleading. Apple's own overview suggests the adapter can be used with a dock:


But it is the last part of the sentence that I think spells out the limitation: to any of the Thunderbolt 3 (USB-C) / USB 4 ports on your Mac. So, the adapter supports connecting a TB2 dock to a TB3 Mac but does not support connecting a TB3 dock to a TB2 Mac.
A Thunderbolt 2 Mac can connect to a Thunderbolt 3 device easily and without issue. Your problem is that you are connecting a Thunderbolt 4 device.

It looks like you were able to get a 10 Gbps x1 Thunderbolt link to the Thunderbolt 4 hub which is just Thunderbolt 1 speed. For Thunderbolt 2, it should be 10 Gbps x2. Maybe the info from ioreg can tell us for sure by matching the Thunderbolt PCIe down adapter with the PCIe path to the NVMe. Perhaps some additional code in EFI could force the Thunderbolt connection to use x2 Thunderbolt link width but that might require Thunderbolt documentation that is not available publicly - all we have is what's in Linux and UEFI open source and some Alpine Ridge and Titan Ridge documentation.

You should be able to get 20 Gbps if you connect the SSD to a Thunderbolt 3 device instead of a Thunderbolt 4 device.

In the USB tab and the PCI tab, the 8086:0b27 is the Goshen Ridge (Thunderbolt 4) USB 3.1 gen 2 PCIe controller of the Thunderbolt 4 hub.

In the PCI tab, the 8086:15f0 is the Titan Ridge (Thunderbolt 3) USB 3.1 gen 2 PCIe controller of the TB4 SSD - which is actually just Thunderbolt 3 with USB support. I guess the USB controller is unused when the SSD is in PCIe (NVMe) mode. The USB controller is probably unused even when the SSD is used in USB mode, since a USB to PCIe (NVMe) bridge like the JMS583 is required for that.
 
A Thunderbolt 2 Mac can connect to a Thunderbolt 3 device easily and without issue. Your problem is that you are connecting a Thunderbolt 4 device.
Ahhh, I think I am beginning to understand what you said. TB4 removed backward compatibility with TB and TB2. If the hub was TB3, which retains backward compatibility with TB and TB2, it would likely enumerate when plugged into a TB2 Mac?

LOL, this is getting to be a very expensive "investigation".
 
Maybe the info from ioreg can tell us for sure by matching the Thunderbolt PCIe down adapter with the PCIe path to the NVMe.
As I understand the Mac Pro 6,1, the TB ports are TB 2. But, looking at the pci-bridge capabilities and negotiated speeds:
1) The MP PLX PCIe switch (UFS0) is showing capabilities = 4 lanes x 8 Gbps = 32 Gbps and negotiated speed of 4 lanes x 5 Gbps = 20 Gbps;
2) The MP Falcon Ridge TB2 bridge is showing capabilities = negotiated speed = 4 lanes x 2.5 Gbps = 10 Gbps;
3) The OWC TB4 hub Goshen Ridge controller is showing capabilities = negotiated speed = 4 lanes x 2.5 Gbps = 10 Gbps;
4) The SSD enclosure TB3 Titan Ridge controller is showing capabilities = 4 lanes x 8 Gbps = 32 Gbps and negotiated speed of 4 lanes x 2.5 Gbps = 10 Gbps.

Falcon Ridge is a TB2 technology with 20 Gbps capability. So, it appears the Falcon Ridge TB2 bridge has not been configured for 20 Gbps for some reason? Driver issue?

Here is the registry for the MP PLX PCIe switch:
Screen Shot 2023-04-07 at 4.12.22 PM.png


Here is the registry for the MP Thunderbolt 2 "Falcon Ridge" bridge:
Screen Shot 2023-04-07 at 1.14.49 PM.png


and here is the registry for the OWC hub TB4 "Goshen Ridge" bridge:
Screen Shot 2023-04-07 at 1.15.18 PM.png
 
As I understand the Mac Pro 6,1, the TB ports are TB 2. But, looking at the pci-bridge capabilities and negotiated speeds:
1) The MP PLX PCIe switch (UFS0) is showing capabilities = 4 lanes x 8 Gbps = 32 Gbps and negotiated speed of 4 lanes x 5 Gbps = 20 Gbps;
Here is the registry for the MP PLX PCIe switch:
The MP PLX has its Upstream at BR00 and its Downstream (indicated by the 6 in IOPCIExpressCapabilities 0x162) at BR10 which connects to upstream of the Falcon Ridge.

For PCIe bridges, there is usually always an upstream bridge device and one or more downstream bridge devices because the upstream can have a different link width and link rate than each of the downstream devices and each downstream device can have a different link width and link rate from each other.

A root port is an exception. It's like a downstream bridge where the upstream is not a PCIe device - it's a platform device (ACPI on Intel Macs). The platform device belongs to the CPU or chipset.

The second 4 least significant bits of the IOPCIExpressCapabilities tells what type of PCIe device it is:
Code:
				 0 PCI Express Endpoint
				 1 Legacy PCI Express Endpoint 
				 4 Root Port of PCI Express Root Complex 
				 5 Upstream Port of PCI Express Switch 
				 6 Downstream Port of PCI Express Switch 
				 7 PCI Express to PCI/PCI-X Bridge 
				 8 PCI/PCI-X to PCI Express Bridge 
				 9 Root Complex Integrated Endpoint 
				10 Root Complex Event Collector

You can use my script ParseIORegPCILinkStatus.sh to parse the ioreg -fliw0 PCIe capabilities and status in the output.
You can try my fork of pciutils to list pci devices. lspci -nnvvv It includes all the PCI info.
My pcitree.sh script will show the PCI hierarchy with the PCI link rate and link width and the PCI name and class info.
https://forums.macrumors.com/threads/allocating-pci-pools.2246466/post-28703877

2) The MP Falcon Ridge TB2 bridge is showing capabilities = negotiated speed = 4 lanes x 2.5 Gbps = 10 Gbps;
Here is the registry for the MP Thunderbolt 2 "Falcon Ridge" bridge:
DSB1 is the downstream of the Falcon Ridge which connects to the upstream of the Goshen Ridge.
UFS0 is the upstream of the Falcon Ridge which connects to the PLX.
DSB0 is the downstream of the Falcon Ridge for its NHI. Under the NHI is the list of Thunderbolt adapters. PCI down adapters are for downstream PCI connections tunnelled over Thunderbolt. DP In Adapters are DisplayPort inputs from the GPU.

If downstream-to-device link is not real PCIe, then the negotiated PCIe link rate and link speed are meaningless.
Examples:
#1) Downstream of a Thunderbolt controller to its NHI controller (or USB4 controller in the case of Thunderbolt 4). The connection is internal to the Thunderbolt controller so PCIe link rate and link width can be ignored.
#2) Downstream of a Thunderbolt 3 or Thunderbolt 4 controller to its USB 3 controller.
#3) Downstream of Thunderbolt controller to upstream of next Thunderbolt controller. In that case, the link is PCIe tunnelled over Thunderbolt.
#4) Upstream of integrated Thunderbolt 3/4 controller. It's internal to the CPU (Ice Lake, Tiger Lake, Apple Silicon) so it's not real PCIe.

DSB1 is a case of #3 so its PCIe link rate can be ignored.

The only PCIe links that are real are those that connect to real PCIe device (the NVMe in your SSD).

3) The OWC TB4 hub Goshen Ridge controller is showing capabilities = negotiated speed = 4 lanes x 2.5 Gbps = 10 Gbps;
and here is the registry for the OWC hub TB4 "Goshen Ridge" bridge:
pci-bridge@1 is the downstream of the Goshen Ridge which connects to the upstream of the Thunderbolt controller of the SSD. This is another case of #3 so ignore its PCIe link rate.
pci-bridge@0 is the downstream of the Goshen Ridge that connects to its USB controller. This is a case of #2. Ignore its PCIe link rate.
UPS0@0 is the upstream of Goshen Ridge that connects to the downstream (DSB1) of Falcon Ridge. This is a case of #3. Ignore its PCIe link rate.

4) The SSD enclosure TB3 Titan Ridge controller is showing capabilities = 4 lanes x 8 Gbps = 32 Gbps and negotiated speed of 4 lanes x 2.5 Gbps = 10 Gbps.
I don't know what upstream or downstream you selected for that reading. If that's the downstream bridge connected to the NVMe then it means the NVMe did not negotiate a 8 GT/s x4 link correctly but you showed in a previous post that the NVMe was at 8 GT/s.

Falcon Ridge is a TB2 technology with 20 Gbps capability. So, it appears the Falcon Ridge TB2 bridge has not been configured for 20 Gbps for some reason? Driver issue?
Driver issue. Both in the EFI and the macOS. Either one could maybe fix the problem.

I did some testing with my iMac14,2. It's only Thunderbolt 1 so I can't test for 20 Gbps links. I connected a CalDigit Element Hub (Thunderbolt 4 hub). It's PCI devices are enumerated when I reboot though it doesn't appear as a Thunderbolt device in System Information.app just like in your testing. pcitree.sh shows Goshen Ridge has one downstream real PCIe capable link of 8 GT/s x1. A CalDigit Thunderbolt 4 Dock uses that for a 2.5 GbE PCIe controller which some people prefer over a USB 2.5 GbE adapter. Every other link is a fake 2.5 GT/s x4. The iMac's Thunderbolt 1 controller is Cactus Ridge with its upstream having status and capabilities of 5 GT/s x4. I tried connecting some displays to the CalDigit Element Hub but nothing happened since the iMac doesn't know about the DisplayPort Down Adapters of the Goshen Ridge. The USB controller of the Goshen Ridge works - I can get 850/734 MB/s read/write. Thunderbolt 2 would allow up to 1060 MB/s probably.
 
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