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USB 2.0 PCIe card for late 2005 Powermac G5

E

eddjedi

macrumors 6502a
Original poster
I have searched but can't find any recent threads on this. I want to add some more USB ports to my 2005 Powermac G5 with PCIe slots. I understand there are no USB 3.0 drivers for Leopard or Tiger. But would a "generic" USB 2.0 card like this work?

www.ebay.co.uk

SafeCom SU2V‑P5 PCIe USB 2.0 Expansion Card 4 Port | eBay UK

Find many great new & used options and get the best deals for SafeCom SU2V‑P5 PCIe USB 2.0 Expansion Card 4 Port at the best online prices at eBay UK! Free delivery for many products!
www.ebay.co.uk

If not any suggestion on which cards do work? Information seems very thin on the ground.
 
eddjedi said:
I have searched but can't find any recent threads on this. I want to add some more USB ports to my 2005 Powermac G5 with PCIe slots. I understand there are no USB 3.0 drivers for Leopard or Tiger. But would a "generic" USB 2.0 card like this work?

www.ebay.co.uk

SafeCom SU2V‑P5 PCIe USB 2.0 Expansion Card 4 Port | eBay UK

Find many great new & used options and get the best deals for SafeCom SU2V‑P5 PCIe USB 2.0 Expansion Card 4 Port at the best online prices at eBay UK! Free delivery for many products!
www.ebay.co.uk

If not any suggestion on which cards do work? Information seems very thin on the ground.
Click to expand...
Are you sure this card is PCI-e?
 
eastone said:
Are you sure this card is PCI-e?
Click to expand...

Thats obviously just PCI😱

Finding an USB2 PCIe card will be a challenge as every PC that had PCIe also had at least USB2 onboard and many early ones also still had PCI ports.

Assuming that a USB3 card won't just work in USB2 fallback (I think that was only the case for USB2 HW with USB1.1 drivers) the best option is to route 1 existing port into an internal HUB and go from there.

I use something like this:
https://www.ebay.de/itm/157901416674?_skw=usb+hub+intern+header
This is to spread from the USB2 card in my QS G4 to the ports provided by the CommodoreGaming case and an 3.5" card reader.

You would also need an adapter from USB-A to header + USB slot cover if you go with the above.
 
put this search in eBay USB 2.0 PCIE -3.0 -3.1 -3.2 and a lot of suitable cards will show up. You'll want an NEC or TI chip for best compatibility. I would avoid VIA cards, although most of those should work just fine.
 
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joevt said:
I wonder how hard it would be to port the GenericUSBXHCI kext to PowerPC Tiger or Leopard.
https://github.com/rehabman/os-x-generic-usb3
Click to expand...
Let's ask AI to summarise the difficulties:

1. Instruction Set Architecture (ISA)
GenericUSBXHCI was written for x86 and x86_64 architectures. PowerPC is a RISC
architecture. You would have to rewrite or recompile every single line of assembly and Cl
C++ hardware manipulation code for the PowerPC processor.

2. I/0 Kit and IOUSBFamily Differences
The driver relies heavily on the modern I/O Kit frameworks introduced in later versions of
OS X. The USB 3.0 stack in Tiger/Leopard simply does not understand eXtensible Host
Controller Interface (xHCI) specifications. You would need to backport the entire xHCI
protocol parsing logic into Leopard's older IOUSBFamily.kext.

3. Processor Specific Quirks
GenericUSHCI relies on features native to Intel and AMD chipsets, like Message
Signaled Interrupts (MSI) and specific bus transaction memory mapping. PowerPC Macs
use entirely different System Controllers (e.g., Apple U3/U4, K2) and PCI-X or AGP
buses.

I mean it sounds like a fun project for someone with a lot of time on their hands. Maybe let AI have a go at this.
 
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weckart said:
Let's ask AI to summarise the difficulties:
Click to expand...
For #1, there's no assembly code. You need to make sure the code is using proper register accessors to account for endian differences.

#2 is probably the biggest issue but I haven't compared the available USB kernel classes between 10.4/10.5 and 10.7/10.8.

#3 not sure about MSI interrupts. Quad G5 has PCIe. For PCI-X/PCI, a PCI to PCIe bridge is needed. I used such a bridge to connect a Nvidia GeForce 7800GT Mac Edition from my Quad G5 to my B&W G3. I suppose the MSI interrupt would be converted to a normal PCI interrupt by the PCI bridge.
 
joevt said:
For #1, there's no assembly code. You need to make sure the code is using proper register accessors to account for endian differences.
Click to expand...
I no longer have my Mac Pro 2008 which had all the Mac OS X versions starting from 10.4.8. My Parallels Desktop VM for Mac OS X 10.5.8 includes USB UHCI, EHCI, and XHCI devices. It has drivers for the first two. So the XHCI driver can be developed for Intel using that then tested on PPC. I haven't been able to get 10.4.8 working in Parallels Desktop but I do have it working in VirtualBox.
 
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