diff options
Diffstat (limited to 'drivers/cxl/acpi.c')
| -rw-r--r-- | drivers/cxl/acpi.c | 100 |
1 files changed, 95 insertions, 5 deletions
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c index 8a723f7f3f73..3afdee8f334a 100644 --- a/drivers/cxl/acpi.c +++ b/drivers/cxl/acpi.c @@ -8,6 +8,60 @@ #include <linux/pci.h> #include "cxl.h" +static struct acpi_table_header *acpi_cedt; + +static struct acpi_cedt_chbs *cxl_acpi_match_chbs(struct device *dev, u32 uid) +{ + struct acpi_cedt_chbs *chbs, *chbs_match = NULL; + acpi_size len, cur = 0; + void *cedt_subtable; + + len = acpi_cedt->length - sizeof(*acpi_cedt); + cedt_subtable = acpi_cedt + 1; + + while (cur < len) { + struct acpi_cedt_header *c = cedt_subtable + cur; + + if (c->type != ACPI_CEDT_TYPE_CHBS) { + cur += c->length; + continue; + } + + chbs = cedt_subtable + cur; + + if (chbs->header.length < sizeof(*chbs)) { + dev_warn_once(dev, + "CHBS entry skipped: invalid length:%u\n", + chbs->header.length); + cur += c->length; + continue; + } + + if (chbs->uid != uid) { + cur += c->length; + continue; + } + + if (chbs_match) { + dev_warn_once(dev, + "CHBS entry skipped: duplicate UID:%u\n", + uid); + cur += c->length; + continue; + } + + chbs_match = chbs; + cur += c->length; + } + + return chbs_match ? chbs_match : ERR_PTR(-ENODEV); +} + +static resource_size_t get_chbcr(struct acpi_cedt_chbs *chbs) +{ + return IS_ERR(chbs) ? CXL_RESOURCE_NONE : chbs->base; +} + struct cxl_walk_context { struct device *dev; struct pci_bus *root; @@ -50,6 +104,21 @@ static int match_add_root_ports(struct pci_dev *pdev, void *data) return 0; } +static struct cxl_dport *find_dport_by_dev(struct cxl_port *port, struct device *dev) +{ + struct cxl_dport *dport; + + device_lock(&port->dev); + list_for_each_entry(dport, &port->dports, list) + if (dport->dport == dev) { + device_unlock(&port->dev); + return dport; + } + + device_unlock(&port->dev); + return NULL; +} + static struct acpi_device *to_cxl_host_bridge(struct device *dev) { struct acpi_device *adev = to_acpi_device(dev); @@ -71,6 +140,7 @@ static int add_host_bridge_uport(struct device *match, void *arg) struct acpi_pci_root *pci_root; struct cxl_walk_context ctx; struct cxl_decoder *cxld; + struct cxl_dport *dport; struct cxl_port *port; if (!bridge) @@ -80,8 +150,14 @@ static int add_host_bridge_uport(struct device *match, void *arg) if (!pci_root) return -ENXIO; - /* TODO: fold in CEDT.CHBS retrieval */ - port = devm_cxl_add_port(host, match, CXL_RESOURCE_NONE, root_port); + dport = find_dport_by_dev(root_port, match); + if (!dport) { + dev_dbg(host, "host bridge expected and not found\n"); + return -ENODEV; + } + + port = devm_cxl_add_port(host, match, dport->component_reg_phys, + root_port); if (IS_ERR(port)) return PTR_ERR(port); dev_dbg(host, "%s: add: %s\n", dev_name(match), dev_name(&port->dev)); @@ -120,6 +196,7 @@ static int add_host_bridge_dport(struct device *match, void *arg) int rc; acpi_status status; unsigned long long uid; + struct acpi_cedt_chbs *chbs; struct cxl_port *root_port = arg; struct device *host = root_port->dev.parent; struct acpi_device *bridge = to_cxl_host_bridge(match); @@ -135,7 +212,12 @@ static int add_host_bridge_dport(struct device *match, void *arg) return -ENODEV; } - rc = cxl_add_dport(root_port, match, uid, CXL_RESOURCE_NONE); + chbs = cxl_acpi_match_chbs(host, uid); + if (IS_ERR(chbs)) + dev_dbg(host, "No CHBS found for Host Bridge: %s\n", + dev_name(match)); + + rc = cxl_add_dport(root_port, match, uid, get_chbcr(chbs)); if (rc) { dev_err(host, "failed to add downstream port: %s\n", dev_name(match)); @@ -172,6 +254,7 @@ static int add_root_nvdimm_bridge(struct device *match, void *data) static int cxl_acpi_probe(struct platform_device *pdev) { int rc; + acpi_status status; struct cxl_port *root_port; struct device *host = &pdev->dev; struct acpi_device *adev = ACPI_COMPANION(host); @@ -181,10 +264,14 @@ static int cxl_acpi_probe(struct platform_device *pdev) return PTR_ERR(root_port); dev_dbg(host, "add: %s\n", dev_name(&root_port->dev)); + status = acpi_get_table(ACPI_SIG_CEDT, 0, &acpi_cedt); + if (ACPI_FAILURE(status)) + return -ENXIO; + rc = bus_for_each_dev(adev->dev.bus, NULL, root_port, add_host_bridge_dport); if (rc) - return rc; + goto out; /* * Root level scanned with host-bridge as dports, now scan host-bridges @@ -193,11 +280,14 @@ static int cxl_acpi_probe(struct platform_device *pdev) rc = bus_for_each_dev(adev->dev.bus, NULL, root_port, add_host_bridge_uport); if (rc) - return rc; + goto out; if (IS_ENABLED(CONFIG_CXL_PMEM)) rc = device_for_each_child(&root_port->dev, root_port, add_root_nvdimm_bridge); + +out: + acpi_put_table(acpi_cedt); if (rc < 0) return rc; return 0; |