diff --git a/arch/powerpc/include/asm/pnv-pci.h b/arch/powerpc/include/asm/pnv-pci.h index 0cbd8134ce81949f8bf079181a7180aa55ee9abb..17e89dd613e190246db5d31212723de041a5a9e0 100644 --- a/arch/powerpc/include/asm/pnv-pci.h +++ b/arch/powerpc/include/asm/pnv-pci.h @@ -60,6 +60,8 @@ struct pnv_php_slot { #define PNV_PHP_STATE_POPULATED 2 #define PNV_PHP_STATE_OFFLINE 3 int state; + int irq; + struct workqueue_struct *wq; struct device_node *dn; struct pci_dev *pdev; struct pci_bus *bus; diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c index 182f218dce4f0ffc9cd510885d495ba9d0a9df0d..5dd0d4f2f907c8cc18ed1a0b3fc170aac74bd9a0 100644 --- a/drivers/pci/hotplug/pnv_php.c +++ b/drivers/pci/hotplug/pnv_php.c @@ -22,6 +22,12 @@ #define DRIVER_AUTHOR "Gavin Shan, IBM Corporation" #define DRIVER_DESC "PowerPC PowerNV PCI Hotplug Driver" +struct pnv_php_event { + bool added; + struct pnv_php_slot *php_slot; + struct work_struct work; +}; + static LIST_HEAD(pnv_php_slot_list); static DEFINE_SPINLOCK(pnv_php_lock); @@ -29,12 +35,40 @@ static void pnv_php_register(struct device_node *dn); static void pnv_php_unregister_one(struct device_node *dn); static void pnv_php_unregister(struct device_node *dn); +static void pnv_php_disable_irq(struct pnv_php_slot *php_slot) +{ + struct pci_dev *pdev = php_slot->pdev; + u16 ctrl; + + if (php_slot->irq > 0) { + pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); + ctrl &= ~(PCI_EXP_SLTCTL_HPIE | + PCI_EXP_SLTCTL_PDCE | + PCI_EXP_SLTCTL_DLLSCE); + pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl); + + free_irq(php_slot->irq, php_slot); + php_slot->irq = 0; + } + + if (php_slot->wq) { + destroy_workqueue(php_slot->wq); + php_slot->wq = NULL; + } + + if (pdev->msix_enabled) + pci_disable_msix(pdev); + else if (pdev->msi_enabled) + pci_disable_msi(pdev); +} + static void pnv_php_free_slot(struct kref *kref) { struct pnv_php_slot *php_slot = container_of(kref, struct pnv_php_slot, kref); WARN_ON(!list_empty(&php_slot->children)); + pnv_php_disable_irq(php_slot); kfree(php_slot->name); kfree(php_slot); } @@ -609,6 +643,181 @@ static int pnv_php_register_slot(struct pnv_php_slot *php_slot) return 0; } +static int pnv_php_enable_msix(struct pnv_php_slot *php_slot) +{ + struct pci_dev *pdev = php_slot->pdev; + struct msix_entry entry; + int nr_entries, ret; + u16 pcie_flag; + + /* Get total number of MSIx entries */ + nr_entries = pci_msix_vec_count(pdev); + if (nr_entries < 0) + return nr_entries; + + /* Check hotplug MSIx entry is in range */ + pcie_capability_read_word(pdev, PCI_EXP_FLAGS, &pcie_flag); + entry.entry = (pcie_flag & PCI_EXP_FLAGS_IRQ) >> 9; + if (entry.entry >= nr_entries) + return -ERANGE; + + /* Enable MSIx */ + ret = pci_enable_msix_exact(pdev, &entry, 1); + if (ret) { + dev_warn(&pdev->dev, "Error %d enabling MSIx\n", ret); + return ret; + } + + return entry.vector; +} + +static void pnv_php_event_handler(struct work_struct *work) +{ + struct pnv_php_event *event = + container_of(work, struct pnv_php_event, work); + struct pnv_php_slot *php_slot = event->php_slot; + + if (event->added) + pnv_php_enable_slot(&php_slot->slot); + else + pnv_php_disable_slot(&php_slot->slot); + + kfree(event); +} + +static irqreturn_t pnv_php_interrupt(int irq, void *data) +{ + struct pnv_php_slot *php_slot = data; + struct pci_dev *pchild, *pdev = php_slot->pdev; + struct eeh_dev *edev; + struct eeh_pe *pe; + struct pnv_php_event *event; + u16 sts, lsts; + u8 presence; + bool added; + unsigned long flags; + int ret; + + pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); + sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); + pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts); + if (sts & PCI_EXP_SLTSTA_DLLSC) { + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lsts); + added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); + } else if (sts & PCI_EXP_SLTSTA_PDC) { + ret = pnv_pci_get_presence_state(php_slot->id, &presence); + if (!ret) + return IRQ_HANDLED; + added = !!(presence == OPAL_PCI_SLOT_PRESENT); + } else { + return IRQ_NONE; + } + + /* Freeze the removed PE to avoid unexpected error reporting */ + if (!added) { + pchild = list_first_entry_or_null(&php_slot->bus->devices, + struct pci_dev, bus_list); + edev = pchild ? pci_dev_to_eeh_dev(pchild) : NULL; + pe = edev ? edev->pe : NULL; + if (pe) { + eeh_serialize_lock(&flags); + eeh_pe_state_mark(pe, EEH_PE_ISOLATED); + eeh_serialize_unlock(flags); + eeh_pe_set_option(pe, EEH_OPT_FREEZE_PE); + } + } + + /* + * The PE is left in frozen state if the event is missed. It's + * fine as the PCI devices (PE) aren't functional any more. + */ + event = kzalloc(sizeof(*event), GFP_ATOMIC); + if (!event) { + dev_warn(&pdev->dev, "PCI slot [%s] missed hotplug event 0x%04x\n", + php_slot->name, sts); + return IRQ_HANDLED; + } + + dev_info(&pdev->dev, "PCI slot [%s] %s (IRQ: %d)\n", + php_slot->name, added ? "added" : "removed", irq); + INIT_WORK(&event->work, pnv_php_event_handler); + event->added = added; + event->php_slot = php_slot; + queue_work(php_slot->wq, &event->work); + + return IRQ_HANDLED; +} + +static void pnv_php_init_irq(struct pnv_php_slot *php_slot, int irq) +{ + struct pci_dev *pdev = php_slot->pdev; + u16 sts, ctrl; + int ret; + + /* Allocate workqueue */ + php_slot->wq = alloc_workqueue("pciehp-%s", 0, 0, php_slot->name); + if (!php_slot->wq) { + dev_warn(&pdev->dev, "Cannot alloc workqueue\n"); + pnv_php_disable_irq(php_slot); + return; + } + + /* Clear pending interrupts */ + pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); + sts |= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); + pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, sts); + + /* Request the interrupt */ + ret = request_irq(irq, pnv_php_interrupt, IRQF_SHARED, + php_slot->name, php_slot); + if (ret) { + pnv_php_disable_irq(php_slot); + dev_warn(&pdev->dev, "Error %d enabling IRQ %d\n", ret, irq); + return; + } + + /* Enable the interrupts */ + pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); + ctrl |= (PCI_EXP_SLTCTL_HPIE | + PCI_EXP_SLTCTL_PDCE | + PCI_EXP_SLTCTL_DLLSCE); + pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, ctrl); + + /* The interrupt is initialized successfully when @irq is valid */ + php_slot->irq = irq; +} + +static void pnv_php_enable_irq(struct pnv_php_slot *php_slot) +{ + struct pci_dev *pdev = php_slot->pdev; + int irq, ret; + + ret = pci_enable_device(pdev); + if (ret) { + dev_warn(&pdev->dev, "Error %d enabling device\n", ret); + return; + } + + pci_set_master(pdev); + + /* Enable MSIx interrupt */ + irq = pnv_php_enable_msix(php_slot); + if (irq > 0) { + pnv_php_init_irq(php_slot, irq); + return; + } + + /* + * Use MSI if MSIx doesn't work. Fail back to legacy INTx + * if MSI doesn't work either + */ + ret = pci_enable_msi(pdev); + if (!ret || pdev->irq) { + irq = pdev->irq; + pnv_php_init_irq(php_slot, irq); + } +} + static int pnv_php_register_one(struct device_node *dn) { struct pnv_php_slot *php_slot; @@ -636,6 +845,11 @@ static int pnv_php_register_one(struct device_node *dn) if (ret) goto unregister_slot; + /* Enable interrupt if the slot supports surprise hotplug */ + prop32 = of_get_property(dn, "ibm,slot-surprise-pluggable", NULL); + if (prop32 && of_read_number(prop32, 1)) + pnv_php_enable_irq(php_slot); + return 0; unregister_slot: