So far, UniPCemu has raised the DRDY status bit to 1 once it receives a PACKET/IDENTIFY PACKET DEVICE command.

Should it actually do that? Or should DRDY always be cleared for PACKET devices(said commands only affecting the BSY bit being cleared)? Is DRDY always ignored by ATAPI device drivers?

Edit: OK. According to the sff-8020i documentation on the ATAPI protocol, the PACKET command sets the DRDY when the command completes(and any result status can be read from the ATA/ATAPI registers), while the IDENTIFY PACKET DEVICE(ATA/ATAPI-4 documentation) sets it once entering it's result phase and giving the identification data to read?