uint64_t tioca_dma_d48 (struct pci_dev * pdev, uint64_t paddr);
Map paddr into 64-bit bus space of the CA associated with pcidev_info.
When direct mapping AGP addresses, the 48 bit AGP address is
[47:40] - Low 8 bits of the page Node ID extracted from coretalk address [47:40]. The upper 8 node bits are fixed and come from the xxx register bits [5:0] [39:38] - Chiplet ID extracted from coretalk address [39:38] [37:00] - node offset extracted from coretalk address [37:00]
Since the node id in general will be non-zero, and the chiplet id will always be non-zero, it follows that the device must support a dma mask of at least 0xffffffffff (40 bits) to target node 0 and in general should be 0xffffffffffff (48 bits) to target nodes up to 255. Nodes above 255 need the support of the xxx register, and so a given CA can only directly target nodes in the range xxx - xxx+255.