cxl/ACPI: Register CXL host ports by bridge device

[linux-2.6-block.git] / drivers / cxl / acpi.c

diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index fb649683dd3ac7bfb08da8047f879497312f4e04..694868a85c93e153f439b46ff7e3435a308a104b 100644 (file)
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -70,6 +70,10 @@ static int cxl_acpi_cfmws_verify(struct device *dev,
        return 0;
 }
 
+/*
+ * Note, @dev must be the first member, see 'struct cxl_chbs_context'
+ * and mock_acpi_table_parse_cedt()
+ */
 struct cxl_cfmws_context {
        struct device *dev;
        struct cxl_port *root_port;
@@ -193,34 +197,34 @@ static int add_host_bridge_uport(struct device *match, void *arg)
 {
        struct cxl_port *root_port = arg;
        struct device *host = root_port->dev.parent;
-       struct acpi_device *bridge = to_cxl_host_bridge(host, match);
+       struct acpi_device *hb = to_cxl_host_bridge(host, match);
        struct acpi_pci_root *pci_root;
        struct cxl_dport *dport;
        struct cxl_port *port;
+       struct device *bridge;
        int rc;
 
-       if (!bridge)
+       if (!hb)
                return 0;
 
-       dport = cxl_find_dport_by_dev(root_port, match);
+       pci_root = acpi_pci_find_root(hb->handle);
+       bridge = pci_root->bus->bridge;
+       dport = cxl_find_dport_by_dev(root_port, bridge);
        if (!dport) {
                dev_dbg(host, "host bridge expected and not found\n");
                return 0;
        }
 
-       /*
-        * Note that this lookup already succeeded in
-        * to_cxl_host_bridge(), so no need to check for failure here
-        */
-       pci_root = acpi_pci_find_root(bridge->handle);
-       rc = devm_cxl_register_pci_bus(host, match, pci_root->bus);
+       rc = devm_cxl_register_pci_bus(host, bridge, pci_root->bus);
        if (rc)
                return rc;
 
-       port = devm_cxl_add_port(host, match, dport->component_reg_phys, dport);
+       port = devm_cxl_add_port(host, bridge, dport->component_reg_phys,
+                                dport);
        if (IS_ERR(port))
                return PTR_ERR(port);
-       dev_dbg(host, "%s: add: %s\n", dev_name(match), dev_name(&port->dev));
+
+       dev_info(bridge, "host supports CXL\n");
 
        return 0;
 }
@@ -251,25 +255,27 @@ static int cxl_get_chbcr(union acpi_subtable_headers *header, void *arg,
 
 static int add_host_bridge_dport(struct device *match, void *arg)
 {
-       acpi_status status;
+       acpi_status rc;
+       struct device *bridge;
        unsigned long long uid;
        struct cxl_dport *dport;
        struct cxl_chbs_context ctx;
+       struct acpi_pci_root *pci_root;
        struct cxl_port *root_port = arg;
        struct device *host = root_port->dev.parent;
-       struct acpi_device *bridge = to_cxl_host_bridge(host, match);
+       struct acpi_device *hb = to_cxl_host_bridge(host, match);
 
-       if (!bridge)
+       if (!hb)
                return 0;
 
-       status = acpi_evaluate_integer(bridge->handle, METHOD_NAME__UID, NULL,
-                                      &uid);
-       if (status != AE_OK) {
-               dev_err(host, "unable to retrieve _UID of %s\n",
-                       dev_name(match));
+       rc = acpi_evaluate_integer(hb->handle, METHOD_NAME__UID, NULL, &uid);
+       if (rc != AE_OK) {
+               dev_err(match, "unable to retrieve _UID\n");
                return -ENODEV;
        }
 
+       dev_dbg(match, "UID found: %lld\n", uid);
+
        ctx = (struct cxl_chbs_context) {
                .dev = host,
                .uid = uid,
@@ -277,18 +283,18 @@ static int add_host_bridge_dport(struct device *match, void *arg)
        acpi_table_parse_cedt(ACPI_CEDT_TYPE_CHBS, cxl_get_chbcr, &ctx);
 
        if (ctx.chbcr == 0) {
-               dev_warn(host, "No CHBS found for Host Bridge: %s\n",
-                        dev_name(match));
+               dev_warn(match, "No CHBS found for Host Bridge (UID %lld)\n", uid);
                return 0;
        }
 
-       dport = devm_cxl_add_dport(root_port, match, uid, ctx.chbcr);
-       if (IS_ERR(dport)) {
-               dev_err(host, "failed to add downstream port: %s\n",
-                       dev_name(match));
+       dev_dbg(match, "CHBCR found: 0x%08llx\n", (u64)ctx.chbcr);
+
+       pci_root = acpi_pci_find_root(hb->handle);
+       bridge = pci_root->bus->bridge;
+       dport = devm_cxl_add_dport(root_port, bridge, uid, ctx.chbcr);
+       if (IS_ERR(dport))
                return PTR_ERR(dport);
-       }
-       dev_dbg(host, "add dport%llu: %s\n", uid, dev_name(match));
+
        return 0;
 }
 
@@ -466,7 +472,6 @@ static int cxl_acpi_probe(struct platform_device *pdev)
        root_port = devm_cxl_add_port(host, host, CXL_RESOURCE_NONE, NULL);
        if (IS_ERR(root_port))
                return PTR_ERR(root_port);
-       dev_dbg(host, "add: %s\n", dev_name(&root_port->dev));
 
        rc = bus_for_each_dev(adev->dev.bus, NULL, root_port,
                              add_host_bridge_dport);
@@ -512,7 +517,8 @@ static int cxl_acpi_probe(struct platform_device *pdev)
                return rc;
 
        /* In case PCI is scanned before ACPI re-trigger memdev attach */
-       return cxl_bus_rescan();
+       cxl_bus_rescan();
+       return 0;
 }
 
 static const struct acpi_device_id cxl_acpi_ids[] = {
@@ -536,7 +542,20 @@ static struct platform_driver cxl_acpi_driver = {
        .id_table = cxl_test_ids,
 };
 
-module_platform_driver(cxl_acpi_driver);
+static int __init cxl_acpi_init(void)
+{
+       return platform_driver_register(&cxl_acpi_driver);
+}
+
+static void __exit cxl_acpi_exit(void)
+{
+       platform_driver_unregister(&cxl_acpi_driver);
+       cxl_bus_drain();
+}
+
+module_init(cxl_acpi_init);
+module_exit(cxl_acpi_exit);
 MODULE_LICENSE("GPL v2");
 MODULE_IMPORT_NS(CXL);
 MODULE_IMPORT_NS(ACPI);
+MODULE_SOFTDEP("pre: cxl_pmem");