On Tue, Jan 28, 2025 at 05:07:35PM -0500, Frank Li wrote: > Rename `cpu_addr` to `parent_bus_addr` in the DesignWare ATU configuration. > The ATU translates parent bus addresses to PCI addresses, which are often > the same as CPU addresses but can differ in systems where the bus fabric > translates addresses before passing them to the PCIe controller. This > renaming clarifies the purpose and avoids confusion. Based on dw_pcie_ep_inbound_atu() below, I guess the ATU can also translate PCI addresses from incoming DMA to parent bus addresses? It's worth noting here that this patch only renames the member, and IIUC, parent_bus_addr still incorrectly contains CPU physical addresses. > +++ b/drivers/pci/controller/dwc/pcie-designware-ep.c > @@ -128,7 +128,7 @@ static int dw_pcie_ep_write_header(struct pci_epc *epc, u8 func_no, u8 vfunc_no, > } > > static int dw_pcie_ep_inbound_atu(struct dw_pcie_ep *ep, u8 func_no, int type, > - dma_addr_t cpu_addr, enum pci_barno bar, > + dma_addr_t parent_bus_addr, enum pci_barno bar, > size_t size)
