diff options
Diffstat (limited to 'drivers/cxl/core/pci.c')
| -rw-r--r-- | drivers/cxl/core/pci.c | 78 |
1 files changed, 48 insertions, 30 deletions
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 96fecb799cbc..b50551601c2e 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -415,17 +415,20 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, */ if (global_ctrl & CXL_HDM_DECODER_ENABLE || (!hdm && info->mem_enabled)) return devm_cxl_enable_mem(&port->dev, cxlds); - else if (!hdm) - return -ENODEV; - root = to_cxl_port(port->dev.parent); - while (!is_cxl_root(root) && is_cxl_port(root->dev.parent)) - root = to_cxl_port(root->dev.parent); - if (!is_cxl_root(root)) { - dev_err(dev, "Failed to acquire root port for HDM enable\n"); + /* + * If the HDM Decoder Capability does not exist and DVSEC was + * not setup, the DVSEC based emulation cannot be used. + */ + if (!hdm) return -ENODEV; - } + /* The HDM Decoder Capability exists but is globally disabled. */ + + /* + * If the DVSEC CXL Range registers are not enabled, just + * enable and use the HDM Decoder Capability registers. + */ if (!info->mem_enabled) { rc = devm_cxl_enable_hdm(&port->dev, cxlhdm); if (rc) @@ -434,6 +437,26 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, return devm_cxl_enable_mem(&port->dev, cxlds); } + /* + * Per CXL 2.0 Section 8.1.3.8.3 and 8.1.3.8.4 DVSEC CXL Range 1 Base + * [High,Low] when HDM operation is enabled the range register values + * are ignored by the device, but the spec also recommends matching the + * DVSEC Range 1,2 to HDM Decoder Range 0,1. So, non-zero info->ranges + * are expected even though Linux does not require or maintain that + * match. Check if at least one DVSEC range is enabled and allowed by + * the platform. That is, the DVSEC range must be covered by a locked + * platform window (CFMWS). Fail otherwise as the endpoint's decoders + * cannot be used. + */ + + root = to_cxl_port(port->dev.parent); + while (!is_cxl_root(root) && is_cxl_port(root->dev.parent)) + root = to_cxl_port(root->dev.parent); + if (!is_cxl_root(root)) { + dev_err(dev, "Failed to acquire root port for HDM enable\n"); + return -ENODEV; + } + for (i = 0, allowed = 0; i < info->ranges; i++) { struct device *cxld_dev; @@ -453,15 +476,6 @@ int cxl_hdm_decode_init(struct cxl_dev_state *cxlds, struct cxl_hdm *cxlhdm, return -ENXIO; } - /* - * Per CXL 2.0 Section 8.1.3.8.3 and 8.1.3.8.4 DVSEC CXL Range 1 Base - * [High,Low] when HDM operation is enabled the range register values - * are ignored by the device, but the spec also recommends matching the - * DVSEC Range 1,2 to HDM Decoder Range 0,1. So, non-zero info->ranges - * are expected even though Linux does not require or maintain that - * match. If at least one DVSEC range is enabled and allowed, skip HDM - * Decoder Capability Enable. - */ return 0; } EXPORT_SYMBOL_NS_GPL(cxl_hdm_decode_init, "CXL"); @@ -1072,14 +1086,20 @@ int cxl_pci_get_bandwidth(struct pci_dev *pdev, struct access_coordinate *c) #define GPF_TIMEOUT_BASE_MAX 2 #define GPF_TIMEOUT_SCALE_MAX 7 /* 10 seconds */ -u16 cxl_gpf_get_dvsec(struct device *dev, bool is_port) +u16 cxl_gpf_get_dvsec(struct device *dev) { + struct pci_dev *pdev; + bool is_port = true; u16 dvsec; if (!dev_is_pci(dev)) return 0; - dvsec = pci_find_dvsec_capability(to_pci_dev(dev), PCI_VENDOR_ID_CXL, + pdev = to_pci_dev(dev); + if (pci_pcie_type(pdev) == PCI_EXP_TYPE_ENDPOINT) + is_port = false; + + dvsec = pci_find_dvsec_capability(pdev, PCI_VENDOR_ID_CXL, is_port ? CXL_DVSEC_PORT_GPF : CXL_DVSEC_DEVICE_GPF); if (!dvsec) dev_warn(dev, "%s GPF DVSEC not present\n", @@ -1128,26 +1148,24 @@ static int update_gpf_port_dvsec(struct pci_dev *pdev, int dvsec, int phase) return rc; } -int cxl_gpf_port_setup(struct device *dport_dev, struct cxl_port *port) +int cxl_gpf_port_setup(struct cxl_dport *dport) { - struct pci_dev *pdev; - - if (!port) + if (!dport) return -EINVAL; - if (!port->gpf_dvsec) { + if (!dport->gpf_dvsec) { + struct pci_dev *pdev; int dvsec; - dvsec = cxl_gpf_get_dvsec(dport_dev, true); + dvsec = cxl_gpf_get_dvsec(dport->dport_dev); if (!dvsec) return -EINVAL; - port->gpf_dvsec = dvsec; + dport->gpf_dvsec = dvsec; + pdev = to_pci_dev(dport->dport_dev); + update_gpf_port_dvsec(pdev, dport->gpf_dvsec, 1); + update_gpf_port_dvsec(pdev, dport->gpf_dvsec, 2); } - pdev = to_pci_dev(dport_dev); - update_gpf_port_dvsec(pdev, port->gpf_dvsec, 1); - update_gpf_port_dvsec(pdev, port->gpf_dvsec, 2); - return 0; } |