@balaton
Sorry, this is with a real machine. After the success with getting a RadeonRX working with QEMU + passthrough, kas1e wanted to see if we could get it working on a real Pegasos II.
We've kind of hit a brick wall. The OS & driver need to be able to access the PCI configuration registers, but they're not responding...
Quote:
If this is through a bridge you may need to do something differently to access the other bus behind the bridge otherwise you may try to read device on the host bus not the bridge's bus so you'd get non-existing device that would return 0xff when you read it (which may be interpreted as 0 for BARs, I'm not sure). Maybe check some docs on how to handle PCI buses behind a bridge and check if the AmigaOS kernel does that correctly.
The OS is using OpenFirmware's own callback function to access configuration registers. You tell it which domain, bus, & device you want to access, and it does it for you. That function is working with all other devices, but not with the graphics card behind the PCI to PCIe bridge. It reads zeros from the GPU's configuration registers, and 0xFFFFFFFF from the card's audio sub-device.
Hans