/* * File: portdrv_core.c * Purpose: PCI Express Port Bus Driver's Core Functions * * Copyright (C) 2004 Intel * Copyright (C) Tom Long Nguyen (tom.l.nguyen@intel.com) */ #include #include #include #include #include #include #include #include #include "../pci.h" #include "portdrv.h" /** * release_pcie_device - free PCI Express port service device structure * @dev: Port service device to release * * Invoked automatically when device is being removed in response to * device_unregister(dev). Release all resources being claimed. */ static void release_pcie_device(struct device *dev) { kfree(to_pcie_device(dev)); } /** * pcie_port_msix_add_entry - add entry to given array of MSI-X entries * @entries: Array of MSI-X entries * @new_entry: Index of the entry to add to the array * @nr_entries: Number of entries aleady in the array * * Return value: Position of the added entry in the array */ static int pcie_port_msix_add_entry( struct msix_entry *entries, int new_entry, int nr_entries) { int j; for (j = 0; j < nr_entries; j++) if (entries[j].entry == new_entry) return j; entries[j].entry = new_entry; return j; } /** * pcie_port_enable_msix - try to set up MSI-X as interrupt mode for given port * @dev: PCI Express port to handle * @vectors: Array of interrupt vectors to populate * @mask: Bitmask of port capabilities returned by get_port_device_capability() * * Return value: 0 on success, error code on failure */ static int pcie_port_enable_msix(struct pci_dev *dev, int *vectors, int mask) { struct msix_entry *msix_entries; int idx[PCIE_PORT_DEVICE_MAXSERVICES]; int nr_entries, status, pos, i, nvec; u16 reg16; u32 reg32; nr_entries = pci_msix_table_size(dev); if (!nr_entries) return -EINVAL; if (nr_entries > PCIE_PORT_MAX_MSIX_ENTRIES) nr_entries = PCIE_PORT_MAX_MSIX_ENTRIES; msix_entries = kzalloc(sizeof(*msix_entries) * nr_entries, GFP_KERNEL); if (!msix_entries) return -ENOMEM; /* * Allocate as many entries as the port wants, so that we can check * which of them will be useful. Moreover, if nr_entries is correctly * equal to the number of entries this port actually uses, we'll happily * go through without any tricks. */ for (i = 0; i < nr_entries; i++) msix_entries[i].entry = i; status = pci_enable_msix(dev, msix_entries, nr_entries); if (status) goto Exit; for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) idx[i] = -1; status = -EIO; nvec = 0; if (mask & (PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP)) { int entry; /* * The code below follows the PCI Express Base Specification 2.0 * stating in Section 6.1.6 that "PME and Hot-Plug Event * interrupts (when both are implemented) always share the same * MSI or MSI-X vector, as indicated by the Interrupt Message * Number field in the PCI Express Capabilities register", where * according to Section 7.8.2 of the specification "For MSI-X, * the value in this field indicates which MSI-X Table entry is * used to generate the interrupt message." */ pos = pci_find_capability(dev, PCI_CAP_ID_EXP); pci_read_config_word(dev, pos + PCIE_CAPABILITIES_REG, ®16); entry = (reg16 >> 9) & PCIE_PORT_MSI_VECTOR_MASK; if (entry >= nr_entries) goto Error; i = pcie_port_msix_add_entry(msix_entries, entry, nvec); if (i == nvec) nvec++; idx[PCIE_PORT_SERVICE_PME_SHIFT] = i; idx[PCIE_PORT_SERVICE_HP_SHIFT] = i; } if (mask & PCIE_PORT_SERVICE_AER) { int entry; /* * The code below follows Section 7.10.10 of the PCI Express * Base Specification 2.0 stating that bits 31-27 of the Root * Error Status Register contain a value indicating which of the * MSI/MSI-X vectors assigned to the port is going to be used * for AER, where "For MSI-X, the value in this register * indicates which MSI-X Table entry is used to generate the * interrupt message." */ pos = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR); pci_read_config_dword(dev, pos + PCI_ERR_ROOT_STATUS, ®32); entry = reg32 >> 27; if (entry >= nr_entries) goto Error; i = pcie_port_msix_add_entry(msix_entries, entry, nvec); if (i == nvec) nvec++; idx[PCIE_PORT_SERVICE_AER_SHIFT] = i; } /* * If nvec is equal to the allocated number of entries, we can just use * what we have. Otherwise, the port has some extra entries not for the * services we know and we need to work around that. */ if (nvec == nr_entries) { status = 0; } else { /* Drop the temporary MSI-X setup */ pci_disable_msix(dev); /* Now allocate the MSI-X vectors for real */ status = pci_enable_msix(dev, msix_entries, nvec); if (status) goto Exit; } for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) vectors[i] = idx[i] >= 0 ? msix_entries[idx[i]].vector : -1; Exit: kfree(msix_entries); return status; Error: pci_disable_msix(dev); goto Exit; } /** * assign_interrupt_mode - choose interrupt mode for PCI Express port services * (INTx, MSI-X, MSI) and set up vectors * @dev: PCI Express port to handle * @vectors: Array of interrupt vectors to populate * @mask: Bitmask of port capabilities returned by get_port_device_capability() * * Return value: Interrupt mode associated with the port */ static int assign_interrupt_mode(struct pci_dev *dev, int *vectors, int mask) { int irq, interrupt_mode = PCIE_PORT_NO_IRQ; int i; /* Try to use MSI-X if supported */ if (!pcie_port_enable_msix(dev, vectors, mask)) return PCIE_PORT_MSIX_MODE; /* We're not going to use MSI-X, so try MSI and fall back to INTx */ if (!pci_enable_msi(dev)) interrupt_mode = PCIE_PORT_MSI_MODE; if (interrupt_mode == PCIE_PORT_NO_IRQ && dev->pin) interrupt_mode = PCIE_PORT_INTx_MODE; irq = interrupt_mode != PCIE_PORT_NO_IRQ ? dev->irq : -1; for (i = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) vectors[i] = irq; vectors[PCIE_PORT_SERVICE_VC_SHIFT] = -1; return interrupt_mode; } /** * get_port_device_capability - discover capabilities of a PCI Express port * @dev: PCI Express port to examine * * The capabilities are read from the port's PCI Express configuration registers * as described in PCI Express Base Specification 1.0a sections 7.8.2, 7.8.9 and * 7.9 - 7.11. * * Return value: Bitmask of discovered port capabilities */ static int get_port_device_capability(struct pci_dev *dev) { int services = 0, pos; u16 reg16; u32 reg32; pos = pci_find_capability(dev, PCI_CAP_ID_EXP); pci_read_config_word(dev, pos + PCIE_CAPABILITIES_REG, ®16); /* Hot-Plug Capable */ if (reg16 & PORT_TO_SLOT_MASK) { pci_read_config_dword(dev, pos + PCIE_SLOT_CAPABILITIES_REG, ®32); if (reg32 & SLOT_HP_CAPABLE_MASK) services |= PCIE_PORT_SERVICE_HP; } /* AER capable */ if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_ERR)) services |= PCIE_PORT_SERVICE_AER; /* VC support */ if (pci_find_ext_capability(dev, PCI_EXT_CAP_ID_VC)) services |= PCIE_PORT_SERVICE_VC; return services; } /** * pcie_device_init - initialize PCI Express port service device * @dev: Port service device to initialize * @parent: PCI Express port to associate the service device with * @port_type: Type of the port * @service_type: Type of service to associate with the service device * @irq: Interrupt vector to associate with the service device */ static void pcie_device_init(struct pci_dev *parent, struct pcie_device *dev, int service_type, int irq) { struct pcie_port_data *port_data = pci_get_drvdata(parent); struct device *device; int port_type = port_data->port_type; dev->port = parent; dev->irq = irq; dev->service = service_type; /* Initialize generic device interface */ device = &dev->device; memset(device, 0, sizeof(struct device)); device->bus = &pcie_port_bus_type; device->driver = NULL; dev_set_drvdata(device, NULL); device->release = release_pcie_device; /* callback to free pcie dev */ dev_set_name(device, "%s:pcie%02x", pci_name(parent), get_descriptor_id(port_type, service_type)); device->parent = &parent->dev; } /** * alloc_pcie_device - allocate PCI Express port service device structure * @parent: PCI Express port to associate the service device with * @port_type: Type of the port * @service_type: Type of service to associate with the service device * @irq: Interrupt vector to associate with the service device */ static struct pcie_device* alloc_pcie_device(struct pci_dev *parent, int service_type, int irq) { struct pcie_device *device; device = kzalloc(sizeof(struct pcie_device), GFP_KERNEL); if (!device) return NULL; pcie_device_init(parent, device, service_type, irq); return device; } /** * pcie_port_device_probe - check if device is a PCI Express port * @dev: Device to check */ int pcie_port_device_probe(struct pci_dev *dev) { int pos, type; u16 reg; if (!(pos = pci_find_capability(dev, PCI_CAP_ID_EXP))) return -ENODEV; pci_read_config_word(dev, pos + PCIE_CAPABILITIES_REG, ®); type = (reg >> 4) & PORT_TYPE_MASK; if ( type == PCIE_RC_PORT || type == PCIE_SW_UPSTREAM_PORT || type == PCIE_SW_DOWNSTREAM_PORT ) return 0; return -ENODEV; } /** * pcie_port_device_register - register PCI Express port * @dev: PCI Express port to register * * Allocate the port extension structure and register services associated with * the port. */ int pcie_port_device_register(struct pci_dev *dev) { struct pcie_port_data *port_data; int status, capabilities, irq_mode, i, nr_serv; int vectors[PCIE_PORT_DEVICE_MAXSERVICES]; u16 reg16; port_data = kzalloc(sizeof(*port_data), GFP_KERNEL); if (!port_data) return -ENOMEM; pci_set_drvdata(dev, port_data); /* Get port type */ pci_read_config_word(dev, pci_find_capability(dev, PCI_CAP_ID_EXP) + PCIE_CAPABILITIES_REG, ®16); port_data->port_type = (reg16 >> 4) & PORT_TYPE_MASK; capabilities = get_port_device_capability(dev); /* Root ports are capable of generating PME too */ if (port_data->port_type == PCIE_RC_PORT) capabilities |= PCIE_PORT_SERVICE_PME; irq_mode = assign_interrupt_mode(dev, vectors, capabilities); if (irq_mode == PCIE_PORT_NO_IRQ) { /* * Don't use service devices that require interrupts if there is * no way to generate them. */ if (!(capabilities & PCIE_PORT_SERVICE_VC)) { status = -ENODEV; goto Error; } capabilities = PCIE_PORT_SERVICE_VC; } port_data->port_irq_mode = irq_mode; status = pci_enable_device(dev); if (status) goto Error; pci_set_master(dev); /* Allocate child services if any */ for (i = 0, nr_serv = 0; i < PCIE_PORT_DEVICE_MAXSERVICES; i++) { struct pcie_device *child; int service = 1 << i; if (!(capabilities & service)) continue; child = alloc_pcie_device(dev, service, vectors[i]); if (!child) continue; status = device_register(&child->device); if (status) { kfree(child); continue; } get_device(&child->device); nr_serv++; } if (!nr_serv) { pci_disable_device(dev); status = -ENODEV; goto Error; } return 0; Error: kfree(port_data); return status; } #ifdef CONFIG_PM static int suspend_iter(struct device *dev, void *data) { struct pcie_port_service_driver *service_driver; if ((dev->bus == &pcie_port_bus_type) && (dev->driver)) { service_driver = to_service_driver(dev->driver); if (service_driver->suspend) service_driver->suspend(to_pcie_device(dev)); } return 0; } /** * pcie_port_device_suspend - suspend port services associated with a PCIe port * @dev: PCI Express port to handle */ int pcie_port_device_suspend(struct device *dev) { return device_for_each_child(dev, NULL, suspend_iter); } static int resume_iter(struct device *dev, void *data) { struct pcie_port_service_driver *service_driver; if ((dev->bus == &pcie_port_bus_type) && (dev->driver)) { service_driver = to_service_driver(dev->driver); if (service_driver->resume) service_driver->resume(to_pcie_device(dev)); } return 0; } /** * pcie_port_device_suspend - resume port services associated with a PCIe port * @dev: PCI Express port to handle */ int pcie_port_device_resume(struct device *dev) { return device_for_each_child(dev, NULL, resume_iter); } #endif /* PM */ static int remove_iter(struct device *dev, void *data) { if (dev->bus == &pcie_port_bus_type) { put_device(dev); device_unregister(dev); } return 0; } /** * pcie_port_device_remove - unregister PCI Express port service devices * @dev: PCI Express port the service devices to unregister are associated with * * Remove PCI Express port service devices associated with given port and * disable MSI-X or MSI for the port. */ void pcie_port_device_remove(struct pci_dev *dev) { struct pcie_port_data *port_data = pci_get_drvdata(dev); device_for_each_child(&dev->dev, NULL, remove_iter); pci_disable_device(dev); switch (port_data->port_irq_mode) { case PCIE_PORT_MSIX_MODE: pci_disable_msix(dev); break; case PCIE_PORT_MSI_MODE: pci_disable_msi(dev); break; } kfree(port_data); } /** * pcie_port_probe_service - probe driver for given PCI Express port service * @dev: PCI Express port service device to probe against * * If PCI Express port service driver is registered with * pcie_port_service_register(), this function will be called by the driver core * whenever match is found between the driver and a port service device. */ static int pcie_port_probe_service(struct device *dev) { struct pcie_device *pciedev; struct pcie_port_service_driver *driver; int status; if (!dev || !dev->driver) return -ENODEV; driver = to_service_driver(dev->driver); if (!driver || !driver->probe) return -ENODEV; pciedev = to_pcie_device(dev); status = driver->probe(pciedev); if (!status) { dev_printk(KERN_DEBUG, dev, "service driver %s loaded\n", driver->name); get_device(dev); } return status; } /** * pcie_port_remove_service - detach driver from given PCI Express port service * @dev: PCI Express port service device to handle * * If PCI Express port service driver is registered with * pcie_port_service_register(), this function will be called by the driver core * when device_unregister() is called for the port service device associated * with the driver. */ static int pcie_port_remove_service(struct device *dev) { struct pcie_device *pciedev; struct pcie_port_service_driver *driver; if (!dev || !dev->driver) return 0; pciedev = to_pcie_device(dev); driver = to_service_driver(dev->driver); if (driver && driver->remove) { dev_printk(KERN_DEBUG, dev, "unloading service driver %s\n", driver->name); driver->remove(pciedev); put_device(dev); } return 0; } /** * pcie_port_shutdown_service - shut down given PCI Express port service * @dev: PCI Express port service device to handle * * If PCI Express port service driver is registered with * pcie_port_service_register(), this function will be called by the driver core * when device_shutdown() is called for the port service device associated * with the driver. */ static void pcie_port_shutdown_service(struct device *dev) {} /** * pcie_port_service_register - register PCI Express port service driver * @new: PCI Express port service driver to register */ int pcie_port_service_register(struct pcie_port_service_driver *new) { new->driver.name = (char *)new->name; new->driver.bus = &pcie_port_bus_type; new->driver.probe = pcie_port_probe_service; new->driver.remove = pcie_port_remove_service; new->driver.shutdown = pcie_port_shutdown_service; return driver_register(&new->driver); } /** * pcie_port_service_unregister - unregister PCI Express port service driver * @drv: PCI Express port service driver to unregister */ void pcie_port_service_unregister(struct pcie_port_service_driver *drv) { driver_unregister(&drv->driver); } EXPORT_SYMBOL(pcie_port_service_register); EXPORT_SYMBOL(pcie_port_service_unregister);