> +/* > + * We extract 4bit node id (bit 44~47) from Loongson-3's > + * 48bit physical address space and embed it into 40bit. > + */ > + > +static int node_id_offset; > + > +static dma_addr_t loongson_phys_to_dma(struct device *dev, phys_addr_t paddr) > +{ > + long nid = (paddr >> 44) & 0xf; > + > + return ((nid << 44) ^ paddr) | (nid << node_id_offset); > +} > + > +static phys_addr_t loongson_dma_to_phys(struct device *dev, dma_addr_t daddr) > +{ > + long nid = (daddr >> node_id_offset) & 0xf; > + > + return ((nid << node_id_offset) ^ daddr) | (nid << 44); > +} > + > +static struct loongson_addr_xlate_ops { > + dma_addr_t (*phys_to_dma)(struct device *dev, phys_addr_t paddr); > + phys_addr_t (*dma_to_phys)(struct device *dev, dma_addr_t daddr); > +} xlate_ops; > + > +dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr) > +{ > + return xlate_ops.phys_to_dma(dev, paddr); > +} > + > +phys_addr_t dma_to_phys(struct device *dev, dma_addr_t daddr) > +{ > + return xlate_ops.dma_to_phys(dev, daddr); > +} Please don't add unused indirections. Also please just use the generic translations