diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index e0d2e75964402ad97a53c759fbfd253d59607ae0..679226023f0c4ecf077cbbdd4ecc6b514aa51173 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -1480,6 +1480,13 @@ int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd) } EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_ports, CXL); +struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev, + struct cxl_dport **dport) +{ + return find_cxl_port(pdev->dev.parent, dport); +} +EXPORT_SYMBOL_NS_GPL(cxl_pci_find_port, CXL); + struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd, struct cxl_dport **dport) { diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 7fbc52b81554ad58cd2bf94ae222666c498dc34a..fe95f08acb69d898b7f2b2e91ce3cfd7975d56c9 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -664,6 +664,8 @@ struct cxl_port *find_cxl_root(struct cxl_port *port); int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd); void cxl_bus_rescan(void); void cxl_bus_drain(void); +struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev, + struct cxl_dport **dport); struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd, struct cxl_dport **dport); bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd); diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 7638a7f8f333c6235378fc00494af6444f4ac66d..205e2e280aed74172c738904e4010d5a00dd54e9 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -65,15 +65,6 @@ static int devm_cxl_add_endpoint(struct device *host, struct cxl_memdev *cxlmd, ep->next = down; } - /* - * The component registers for an RCD might come from the - * host-bridge RCRB if they are not already mapped via the - * typical register locator mechanism. - */ - if (parent_dport->rch && cxlds->component_reg_phys == CXL_RESOURCE_NONE) - cxlds->component_reg_phys = - cxl_rcd_component_reg_phys(&cxlmd->dev, parent_dport); - endpoint = devm_cxl_add_port(host, &cxlmd->dev, cxlds->component_reg_phys, parent_dport); diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index 945ca0304d6874e2277e5a5b7d232699438ae115..99a75c54ee39e0326d02666027297328c00b928f 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -274,27 +274,66 @@ static int cxl_pci_setup_mailbox(struct cxl_dev_state *cxlds) return 0; } +/* + * Assume that any RCIEP that emits the CXL memory expander class code + * is an RCD + */ +static bool is_cxl_restricted(struct pci_dev *pdev) +{ + return pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END; +} + +static int cxl_rcrb_get_comp_regs(struct pci_dev *pdev, + struct cxl_register_map *map) +{ + struct cxl_port *port; + struct cxl_dport *dport; + resource_size_t component_reg_phys; + + *map = (struct cxl_register_map) { + .dev = &pdev->dev, + .resource = CXL_RESOURCE_NONE, + }; + + port = cxl_pci_find_port(pdev, &dport); + if (!port) + return -EPROBE_DEFER; + + component_reg_phys = cxl_rcd_component_reg_phys(&pdev->dev, dport); + + put_device(&port->dev); + + if (component_reg_phys == CXL_RESOURCE_NONE) + return -ENXIO; + + map->resource = component_reg_phys; + map->reg_type = CXL_REGLOC_RBI_COMPONENT; + map->max_size = CXL_COMPONENT_REG_BLOCK_SIZE; + + return 0; +} + static int cxl_pci_setup_regs(struct pci_dev *pdev, enum cxl_regloc_type type, struct cxl_register_map *map) { int rc; rc = cxl_find_regblock(pdev, type, map); + + /* + * If the Register Locator DVSEC does not exist, check if it + * is an RCH and try to extract the Component Registers from + * an RCRB. + */ + if (rc && type == CXL_REGLOC_RBI_COMPONENT && is_cxl_restricted(pdev)) + rc = cxl_rcrb_get_comp_regs(pdev, map); + if (rc) return rc; return cxl_setup_regs(map); } -/* - * Assume that any RCIEP that emits the CXL memory expander class code - * is an RCD - */ -static bool is_cxl_restricted(struct pci_dev *pdev) -{ - return pci_pcie_type(pdev) == PCI_EXP_TYPE_RC_END; -} - /* * CXL v3.0 6.2.3 Table 6-4 * The table indicates that if PCIe Flit Mode is set, then CXL is in 256B flits