diff options
Diffstat (limited to 'drivers/misc/cxl/pci.c')
-rw-r--r-- | drivers/misc/cxl/pci.c | 236 |
1 files changed, 18 insertions, 218 deletions
diff --git a/drivers/misc/cxl/pci.c b/drivers/misc/cxl/pci.c index 429d6de1dde7..9c5a21fee835 100644 --- a/drivers/misc/cxl/pci.c +++ b/drivers/misc/cxl/pci.c @@ -55,8 +55,6 @@ pci_read_config_byte(dev, vsec + 0xa, dest) #define CXL_WRITE_VSEC_MODE_CONTROL(dev, vsec, val) \ pci_write_config_byte(dev, vsec + 0xa, val) -#define CXL_WRITE_VSEC_MODE_CONTROL_BUS(bus, devfn, vsec, val) \ - pci_bus_write_config_byte(bus, devfn, vsec + 0xa, val) #define CXL_VSEC_PROTOCOL_MASK 0xe0 #define CXL_VSEC_PROTOCOL_1024TB 0x80 #define CXL_VSEC_PROTOCOL_512TB 0x40 @@ -800,234 +798,36 @@ static int setup_cxl_bars(struct pci_dev *dev) return 0; } -#ifdef CONFIG_CXL_BIMODAL - -struct cxl_switch_work { - struct pci_dev *dev; - struct work_struct work; - int vsec; - int mode; -}; - -static void switch_card_to_cxl(struct work_struct *work) +/* pciex node: ibm,opal-m64-window = <0x3d058 0x0 0x3d058 0x0 0x8 0x0>; */ +static int switch_card_to_cxl(struct pci_dev *dev) { - struct cxl_switch_work *switch_work = - container_of(work, struct cxl_switch_work, work); - struct pci_dev *dev = switch_work->dev; - struct pci_bus *bus = dev->bus; - struct pci_controller *hose = pci_bus_to_host(bus); - struct pci_dev *bridge; - struct pnv_php_slot *php_slot; - unsigned int devfn; + int vsec; u8 val; int rc; - dev_info(&bus->dev, "cxl: Preparing for mode switch...\n"); - bridge = list_first_entry_or_null(&hose->bus->devices, struct pci_dev, - bus_list); - if (!bridge) { - dev_WARN(&bus->dev, "cxl: Couldn't find root port!\n"); - goto err_dev_put; - } + dev_info(&dev->dev, "switch card to CXL\n"); - php_slot = pnv_php_find_slot(pci_device_to_OF_node(bridge)); - if (!php_slot) { - dev_err(&bus->dev, "cxl: Failed to find slot hotplug " - "information. You may need to upgrade " - "skiboot. Aborting.\n"); - goto err_dev_put; - } - - rc = CXL_READ_VSEC_MODE_CONTROL(dev, switch_work->vsec, &val); - if (rc) { - dev_err(&bus->dev, "cxl: Failed to read CAPI mode control: %i\n", rc); - goto err_dev_put; - } - devfn = dev->devfn; - - /* Release the reference obtained in cxl_check_and_switch_mode() */ - pci_dev_put(dev); - - dev_dbg(&bus->dev, "cxl: Removing PCI devices from kernel\n"); - pci_lock_rescan_remove(); - pci_hp_remove_devices(bridge->subordinate); - pci_unlock_rescan_remove(); - - /* Switch the CXL protocol on the card */ - if (switch_work->mode == CXL_BIMODE_CXL) { - dev_info(&bus->dev, "cxl: Switching card to CXL mode\n"); - val &= ~CXL_VSEC_PROTOCOL_MASK; - val |= CXL_VSEC_PROTOCOL_256TB | CXL_VSEC_PROTOCOL_ENABLE; - rc = pnv_cxl_enable_phb_kernel_api(hose, true); - if (rc) { - dev_err(&bus->dev, "cxl: Failed to enable kernel API" - " on real PHB, aborting\n"); - goto err_free_work; - } - } else { - dev_WARN(&bus->dev, "cxl: Switching card to PCI mode not supported!\n"); - goto err_free_work; - } - - rc = CXL_WRITE_VSEC_MODE_CONTROL_BUS(bus, devfn, switch_work->vsec, val); - if (rc) { - dev_err(&bus->dev, "cxl: Failed to configure CXL protocol: %i\n", rc); - goto err_free_work; - } - - /* - * The CAIA spec (v1.1, Section 10.6 Bi-modal Device Support) states - * we must wait 100ms after this mode switch before touching PCIe config - * space. - */ - msleep(100); - - /* - * Hot reset to cause the card to come back in cxl mode. A - * OPAL_RESET_PCI_LINK would be sufficient, but currently lacks support - * in skiboot, so we use a hot reset instead. - * - * We call pci_set_pcie_reset_state() on the bridge, as a CAPI card is - * guaranteed to sit directly under the root port, and setting the reset - * state on a device directly under the root port is equivalent to doing - * it on the root port iself. - */ - dev_info(&bus->dev, "cxl: Configuration write complete, resetting card\n"); - pci_set_pcie_reset_state(bridge, pcie_hot_reset); - pci_set_pcie_reset_state(bridge, pcie_deassert_reset); - - dev_dbg(&bus->dev, "cxl: Offlining slot\n"); - rc = pnv_php_set_slot_power_state(&php_slot->slot, OPAL_PCI_SLOT_OFFLINE); - if (rc) { - dev_err(&bus->dev, "cxl: OPAL offlining call failed: %i\n", rc); - goto err_free_work; - } - - dev_dbg(&bus->dev, "cxl: Onlining and probing slot\n"); - rc = pnv_php_set_slot_power_state(&php_slot->slot, OPAL_PCI_SLOT_ONLINE); - if (rc) { - dev_err(&bus->dev, "cxl: OPAL onlining call failed: %i\n", rc); - goto err_free_work; - } - - pci_lock_rescan_remove(); - pci_hp_add_devices(bridge->subordinate); - pci_unlock_rescan_remove(); - - dev_info(&bus->dev, "cxl: CAPI mode switch completed\n"); - kfree(switch_work); - return; - -err_dev_put: - /* Release the reference obtained in cxl_check_and_switch_mode() */ - pci_dev_put(dev); -err_free_work: - kfree(switch_work); -} - -int cxl_check_and_switch_mode(struct pci_dev *dev, int mode, int vsec) -{ - struct cxl_switch_work *work; - u8 val; - int rc; - - if (!cpu_has_feature(CPU_FTR_HVMODE)) + if (!(vsec = find_cxl_vsec(dev))) { + dev_err(&dev->dev, "ABORTING: CXL VSEC not found!\n"); return -ENODEV; - - if (!vsec) { - vsec = find_cxl_vsec(dev); - if (!vsec) { - dev_info(&dev->dev, "CXL VSEC not found\n"); - return -ENODEV; - } } - rc = CXL_READ_VSEC_MODE_CONTROL(dev, vsec, &val); - if (rc) { - dev_err(&dev->dev, "Failed to read current mode control: %i", rc); + if ((rc = CXL_READ_VSEC_MODE_CONTROL(dev, vsec, &val))) { + dev_err(&dev->dev, "failed to read current mode control: %i", rc); return rc; } - - if (mode == CXL_BIMODE_PCI) { - if (!(val & CXL_VSEC_PROTOCOL_ENABLE)) { - dev_info(&dev->dev, "Card is already in PCI mode\n"); - return 0; - } - /* - * TODO: Before it's safe to switch the card back to PCI mode - * we need to disable the CAPP and make sure any cachelines the - * card holds have been flushed out. Needs skiboot support. - */ - dev_WARN(&dev->dev, "CXL mode switch to PCI unsupported!\n"); - return -EIO; - } - - if (val & CXL_VSEC_PROTOCOL_ENABLE) { - dev_info(&dev->dev, "Card is already in CXL mode\n"); - return 0; + val &= ~CXL_VSEC_PROTOCOL_MASK; + val |= CXL_VSEC_PROTOCOL_256TB | CXL_VSEC_PROTOCOL_ENABLE; + if ((rc = CXL_WRITE_VSEC_MODE_CONTROL(dev, vsec, val))) { + dev_err(&dev->dev, "failed to enable CXL protocol: %i", rc); + return rc; } - - dev_info(&dev->dev, "Card is in PCI mode, scheduling kernel thread " - "to switch to CXL mode\n"); - - work = kmalloc(sizeof(struct cxl_switch_work), GFP_KERNEL); - if (!work) - return -ENOMEM; - - pci_dev_get(dev); - work->dev = dev; - work->vsec = vsec; - work->mode = mode; - INIT_WORK(&work->work, switch_card_to_cxl); - - schedule_work(&work->work); - /* - * We return a failure now to abort the driver init. Once the - * link has been cycled and the card is in cxl mode we will - * come back (possibly using the generic cxl driver), but - * return success as the card should then be in cxl mode. - * - * TODO: What if the card comes back in PCI mode even after - * the switch? Don't want to spin endlessly. + * The CAIA spec (v0.12 11.6 Bi-modal Device Support) states + * we must wait 100ms after this mode switch before touching + * PCIe config space. */ - return -EBUSY; -} -EXPORT_SYMBOL_GPL(cxl_check_and_switch_mode); - -#endif /* CONFIG_CXL_BIMODAL */ - -static int setup_cxl_protocol_area(struct pci_dev *dev) -{ - u8 val; - int rc; - int vsec = find_cxl_vsec(dev); - - if (!vsec) { - dev_info(&dev->dev, "CXL VSEC not found\n"); - return -ENODEV; - } - - rc = CXL_READ_VSEC_MODE_CONTROL(dev, vsec, &val); - if (rc) { - dev_err(&dev->dev, "Failed to read current mode control: %i\n", rc); - return rc; - } - - if (!(val & CXL_VSEC_PROTOCOL_ENABLE)) { - dev_err(&dev->dev, "Card not in CAPI mode!\n"); - return -EIO; - } - - if ((val & CXL_VSEC_PROTOCOL_MASK) != CXL_VSEC_PROTOCOL_256TB) { - val &= ~CXL_VSEC_PROTOCOL_MASK; - val |= CXL_VSEC_PROTOCOL_256TB; - rc = CXL_WRITE_VSEC_MODE_CONTROL(dev, vsec, val); - if (rc) { - dev_err(&dev->dev, "Failed to set CXL protocol area: %i\n", rc); - return rc; - } - } + msleep(100); return 0; } @@ -1724,7 +1524,7 @@ static int cxl_configure_adapter(struct cxl *adapter, struct pci_dev *dev) if ((rc = setup_cxl_bars(dev))) return rc; - if ((rc = setup_cxl_protocol_area(dev))) + if ((rc = switch_card_to_cxl(dev))) return rc; if ((rc = cxl_update_image_control(adapter))) |