diff options
Diffstat (limited to 'drivers/pci/hotplug/pnv_php.c')
| -rw-r--r-- | drivers/pci/hotplug/pnv_php.c | 1049 |
1 files changed, 1049 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c new file mode 100644 index 0000000000..881d420637 --- /dev/null +++ b/drivers/pci/hotplug/pnv_php.c @@ -0,0 +1,1049 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * PCI Hotplug Driver for PowerPC PowerNV platform. + * + * Copyright Gavin Shan, IBM Corporation 2016. + */ + +#include <linux/libfdt.h> +#include <linux/module.h> +#include <linux/pci.h> +#include <linux/pci_hotplug.h> +#include <linux/of_fdt.h> + +#include <asm/opal.h> +#include <asm/pnv-pci.h> +#include <asm/ppc-pci.h> + +#define DRIVER_VERSION "0.1" +#define DRIVER_AUTHOR "Gavin Shan, IBM Corporation" +#define DRIVER_DESC "PowerPC PowerNV PCI Hotplug Driver" + +#define SLOT_WARN(sl, x...) \ + ((sl)->pdev ? pci_warn((sl)->pdev, x) : dev_warn(&(sl)->bus->dev, x)) + +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); + +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, + bool disable_device) +{ + struct pci_dev *pdev = php_slot->pdev; + int irq = php_slot->irq; + 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 (disable_device || irq > 0) { + if (pdev->msix_enabled) + pci_disable_msix(pdev); + else if (pdev->msi_enabled) + pci_disable_msi(pdev); + + pci_disable_device(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, false); + kfree(php_slot->name); + kfree(php_slot); +} + +static inline void pnv_php_put_slot(struct pnv_php_slot *php_slot) +{ + + if (!php_slot) + return; + + kref_put(&php_slot->kref, pnv_php_free_slot); +} + +static struct pnv_php_slot *pnv_php_match(struct device_node *dn, + struct pnv_php_slot *php_slot) +{ + struct pnv_php_slot *target, *tmp; + + if (php_slot->dn == dn) { + kref_get(&php_slot->kref); + return php_slot; + } + + list_for_each_entry(tmp, &php_slot->children, link) { + target = pnv_php_match(dn, tmp); + if (target) + return target; + } + + return NULL; +} + +struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn) +{ + struct pnv_php_slot *php_slot, *tmp; + unsigned long flags; + + spin_lock_irqsave(&pnv_php_lock, flags); + list_for_each_entry(tmp, &pnv_php_slot_list, link) { + php_slot = pnv_php_match(dn, tmp); + if (php_slot) { + spin_unlock_irqrestore(&pnv_php_lock, flags); + return php_slot; + } + } + spin_unlock_irqrestore(&pnv_php_lock, flags); + + return NULL; +} +EXPORT_SYMBOL_GPL(pnv_php_find_slot); + +/* + * Remove pdn for all children of the indicated device node. + * The function should remove pdn in a depth-first manner. + */ +static void pnv_php_rmv_pdns(struct device_node *dn) +{ + struct device_node *child; + + for_each_child_of_node(dn, child) { + pnv_php_rmv_pdns(child); + + pci_remove_device_node_info(child); + } +} + +/* + * Detach all child nodes of the indicated device nodes. The + * function should handle device nodes in depth-first manner. + * + * We should not invoke of_node_release() as the memory for + * individual device node is part of large memory block. The + * large block is allocated from memblock (system bootup) or + * kmalloc() when unflattening the device tree by OF changeset. + * We can not free the large block allocated from memblock. For + * later case, it should be released at once. + */ +static void pnv_php_detach_device_nodes(struct device_node *parent) +{ + struct device_node *dn; + + for_each_child_of_node(parent, dn) { + pnv_php_detach_device_nodes(dn); + + of_node_put(dn); + of_detach_node(dn); + } +} + +static void pnv_php_rmv_devtree(struct pnv_php_slot *php_slot) +{ + pnv_php_rmv_pdns(php_slot->dn); + + /* + * Decrease the refcount if the device nodes were created + * through OF changeset before detaching them. + */ + if (php_slot->fdt) + of_changeset_destroy(&php_slot->ocs); + pnv_php_detach_device_nodes(php_slot->dn); + + if (php_slot->fdt) { + kfree(php_slot->dt); + kfree(php_slot->fdt); + php_slot->dt = NULL; + php_slot->dn->child = NULL; + php_slot->fdt = NULL; + } +} + +/* + * As the nodes in OF changeset are applied in reverse order, we + * need revert the nodes in advance so that we have correct node + * order after the changeset is applied. + */ +static void pnv_php_reverse_nodes(struct device_node *parent) +{ + struct device_node *child, *next; + + /* In-depth first */ + for_each_child_of_node(parent, child) + pnv_php_reverse_nodes(child); + + /* Reverse the nodes in the child list */ + child = parent->child; + parent->child = NULL; + while (child) { + next = child->sibling; + + child->sibling = parent->child; + parent->child = child; + child = next; + } +} + +static int pnv_php_populate_changeset(struct of_changeset *ocs, + struct device_node *dn) +{ + struct device_node *child; + int ret = 0; + + for_each_child_of_node(dn, child) { + ret = of_changeset_attach_node(ocs, child); + if (ret) { + of_node_put(child); + break; + } + + ret = pnv_php_populate_changeset(ocs, child); + if (ret) { + of_node_put(child); + break; + } + } + + return ret; +} + +static void *pnv_php_add_one_pdn(struct device_node *dn, void *data) +{ + struct pci_controller *hose = (struct pci_controller *)data; + struct pci_dn *pdn; + + pdn = pci_add_device_node_info(hose, dn); + if (!pdn) + return ERR_PTR(-ENOMEM); + + return NULL; +} + +static void pnv_php_add_pdns(struct pnv_php_slot *slot) +{ + struct pci_controller *hose = pci_bus_to_host(slot->bus); + + pci_traverse_device_nodes(slot->dn, pnv_php_add_one_pdn, hose); +} + +static int pnv_php_add_devtree(struct pnv_php_slot *php_slot) +{ + void *fdt, *fdt1, *dt; + int ret; + + /* We don't know the FDT blob size. We try to get it through + * maximal memory chunk and then copy it to another chunk that + * fits the real size. + */ + fdt1 = kzalloc(0x10000, GFP_KERNEL); + if (!fdt1) { + ret = -ENOMEM; + goto out; + } + + ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000); + if (ret) { + SLOT_WARN(php_slot, "Error %d getting FDT blob\n", ret); + goto free_fdt1; + } + + fdt = kmemdup(fdt1, fdt_totalsize(fdt1), GFP_KERNEL); + if (!fdt) { + ret = -ENOMEM; + goto free_fdt1; + } + + /* Unflatten device tree blob */ + dt = of_fdt_unflatten_tree(fdt, php_slot->dn, NULL); + if (!dt) { + ret = -EINVAL; + SLOT_WARN(php_slot, "Cannot unflatten FDT\n"); + goto free_fdt; + } + + /* Initialize and apply the changeset */ + of_changeset_init(&php_slot->ocs); + pnv_php_reverse_nodes(php_slot->dn); + ret = pnv_php_populate_changeset(&php_slot->ocs, php_slot->dn); + if (ret) { + pnv_php_reverse_nodes(php_slot->dn); + SLOT_WARN(php_slot, "Error %d populating changeset\n", + ret); + goto free_dt; + } + + php_slot->dn->child = NULL; + ret = of_changeset_apply(&php_slot->ocs); + if (ret) { + SLOT_WARN(php_slot, "Error %d applying changeset\n", ret); + goto destroy_changeset; + } + + /* Add device node firmware data */ + pnv_php_add_pdns(php_slot); + php_slot->fdt = fdt; + php_slot->dt = dt; + kfree(fdt1); + goto out; + +destroy_changeset: + of_changeset_destroy(&php_slot->ocs); +free_dt: + kfree(dt); + php_slot->dn->child = NULL; +free_fdt: + kfree(fdt); +free_fdt1: + kfree(fdt1); +out: + return ret; +} + +static inline struct pnv_php_slot *to_pnv_php_slot(struct hotplug_slot *slot) +{ + return container_of(slot, struct pnv_php_slot, slot); +} + +int pnv_php_set_slot_power_state(struct hotplug_slot *slot, + uint8_t state) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + struct opal_msg msg; + int ret; + + ret = pnv_pci_set_power_state(php_slot->id, state, &msg); + if (ret > 0) { + if (be64_to_cpu(msg.params[1]) != php_slot->dn->phandle || + be64_to_cpu(msg.params[2]) != state) { + SLOT_WARN(php_slot, "Wrong msg (%lld, %lld, %lld)\n", + be64_to_cpu(msg.params[1]), + be64_to_cpu(msg.params[2]), + be64_to_cpu(msg.params[3])); + return -ENOMSG; + } + if (be64_to_cpu(msg.params[3]) != OPAL_SUCCESS) { + ret = -ENODEV; + goto error; + } + } else if (ret < 0) { + goto error; + } + + if (state == OPAL_PCI_SLOT_POWER_OFF || state == OPAL_PCI_SLOT_OFFLINE) + pnv_php_rmv_devtree(php_slot); + else + ret = pnv_php_add_devtree(php_slot); + + return ret; + +error: + SLOT_WARN(php_slot, "Error %d powering %s\n", + ret, (state == OPAL_PCI_SLOT_POWER_ON) ? "on" : "off"); + return ret; +} +EXPORT_SYMBOL_GPL(pnv_php_set_slot_power_state); + +static int pnv_php_get_power_state(struct hotplug_slot *slot, u8 *state) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + uint8_t power_state = OPAL_PCI_SLOT_POWER_ON; + int ret; + + /* + * Retrieve power status from firmware. If we fail + * getting that, the power status fails back to + * be on. + */ + ret = pnv_pci_get_power_state(php_slot->id, &power_state); + if (ret) { + SLOT_WARN(php_slot, "Error %d getting power status\n", + ret); + } else { + *state = power_state; + } + + return 0; +} + +static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + uint8_t presence = OPAL_PCI_SLOT_EMPTY; + int ret; + + /* + * Retrieve presence status from firmware. If we can't + * get that, it will fail back to be empty. + */ + ret = pnv_pci_get_presence_state(php_slot->id, &presence); + if (ret >= 0) { + *state = presence; + ret = 0; + } else { + SLOT_WARN(php_slot, "Error %d getting presence\n", ret); + } + + return ret; +} + +static int pnv_php_get_attention_state(struct hotplug_slot *slot, u8 *state) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + + *state = php_slot->attention_state; + return 0; +} + +static int pnv_php_set_attention_state(struct hotplug_slot *slot, u8 state) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + struct pci_dev *bridge = php_slot->pdev; + u16 new, mask; + + php_slot->attention_state = state; + if (!bridge) + return 0; + + mask = PCI_EXP_SLTCTL_AIC; + + if (state) + new = PCI_EXP_SLTCTL_ATTN_IND_ON; + else + new = PCI_EXP_SLTCTL_ATTN_IND_OFF; + + pcie_capability_clear_and_set_word(bridge, PCI_EXP_SLTCTL, mask, new); + + return 0; +} + +static int pnv_php_enable(struct pnv_php_slot *php_slot, bool rescan) +{ + struct hotplug_slot *slot = &php_slot->slot; + uint8_t presence = OPAL_PCI_SLOT_EMPTY; + uint8_t power_status = OPAL_PCI_SLOT_POWER_ON; + int ret; + + /* Check if the slot has been configured */ + if (php_slot->state != PNV_PHP_STATE_REGISTERED) + return 0; + + /* Retrieve slot presence status */ + ret = pnv_php_get_adapter_state(slot, &presence); + if (ret) + return ret; + + /* + * Proceed if there have nothing behind the slot. However, + * we should leave the slot in registered state at the + * beginning. Otherwise, the PCI devices inserted afterwards + * won't be probed and populated. + */ + if (presence == OPAL_PCI_SLOT_EMPTY) { + if (!php_slot->power_state_check) { + php_slot->power_state_check = true; + + return 0; + } + + goto scan; + } + + /* + * If the power supply to the slot is off, we can't detect + * adapter presence state. That means we have to turn the + * slot on before going to probe slot's presence state. + * + * On the first time, we don't change the power status to + * boost system boot with assumption that the firmware + * supplies consistent slot power status: empty slot always + * has its power off and non-empty slot has its power on. + */ + if (!php_slot->power_state_check) { + php_slot->power_state_check = true; + + ret = pnv_php_get_power_state(slot, &power_status); + if (ret) + return ret; + + if (power_status != OPAL_PCI_SLOT_POWER_ON) + return 0; + } + + /* Check the power status. Scan the slot if it is already on */ + ret = pnv_php_get_power_state(slot, &power_status); + if (ret) + return ret; + + if (power_status == OPAL_PCI_SLOT_POWER_ON) + goto scan; + + /* Power is off, turn it on and then scan the slot */ + ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_ON); + if (ret) + return ret; + +scan: + if (presence == OPAL_PCI_SLOT_PRESENT) { + if (rescan) { + pci_lock_rescan_remove(); + pci_hp_add_devices(php_slot->bus); + pci_unlock_rescan_remove(); + } + + /* Rescan for child hotpluggable slots */ + php_slot->state = PNV_PHP_STATE_POPULATED; + if (rescan) + pnv_php_register(php_slot->dn); + } else { + php_slot->state = PNV_PHP_STATE_POPULATED; + } + + return 0; +} + +static int pnv_php_reset_slot(struct hotplug_slot *slot, bool probe) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + struct pci_dev *bridge = php_slot->pdev; + uint16_t sts; + + /* + * The CAPI folks want pnv_php to drive OpenCAPI slots + * which don't have a bridge. Only claim to support + * reset_slot() if we have a bridge device (for now...) + */ + if (probe) + return !bridge; + + /* mask our interrupt while resetting the bridge */ + if (php_slot->irq > 0) + disable_irq(php_slot->irq); + + pci_bridge_secondary_bus_reset(bridge); + + /* clear any state changes that happened due to the reset */ + pcie_capability_read_word(php_slot->pdev, PCI_EXP_SLTSTA, &sts); + sts &= (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); + pcie_capability_write_word(php_slot->pdev, PCI_EXP_SLTSTA, sts); + + if (php_slot->irq > 0) + enable_irq(php_slot->irq); + + return 0; +} + +static int pnv_php_enable_slot(struct hotplug_slot *slot) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + + return pnv_php_enable(php_slot, true); +} + +static int pnv_php_disable_slot(struct hotplug_slot *slot) +{ + struct pnv_php_slot *php_slot = to_pnv_php_slot(slot); + int ret; + + /* + * Allow to disable a slot already in the registered state to + * cover cases where the slot couldn't be enabled and never + * reached the populated state + */ + if (php_slot->state != PNV_PHP_STATE_POPULATED && + php_slot->state != PNV_PHP_STATE_REGISTERED) + return 0; + + /* Remove all devices behind the slot */ + pci_lock_rescan_remove(); + pci_hp_remove_devices(php_slot->bus); + pci_unlock_rescan_remove(); + + /* Detach the child hotpluggable slots */ + pnv_php_unregister(php_slot->dn); + + /* Notify firmware and remove device nodes */ + ret = pnv_php_set_slot_power_state(slot, OPAL_PCI_SLOT_POWER_OFF); + + php_slot->state = PNV_PHP_STATE_REGISTERED; + return ret; +} + +static const struct hotplug_slot_ops php_slot_ops = { + .get_power_status = pnv_php_get_power_state, + .get_adapter_status = pnv_php_get_adapter_state, + .get_attention_status = pnv_php_get_attention_state, + .set_attention_status = pnv_php_set_attention_state, + .enable_slot = pnv_php_enable_slot, + .disable_slot = pnv_php_disable_slot, + .reset_slot = pnv_php_reset_slot, +}; + +static void pnv_php_release(struct pnv_php_slot *php_slot) +{ + unsigned long flags; + + /* Remove from global or child list */ + spin_lock_irqsave(&pnv_php_lock, flags); + list_del(&php_slot->link); + spin_unlock_irqrestore(&pnv_php_lock, flags); + + /* Detach from parent */ + pnv_php_put_slot(php_slot); + pnv_php_put_slot(php_slot->parent); +} + +static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn) +{ + struct pnv_php_slot *php_slot; + struct pci_bus *bus; + const char *label; + uint64_t id; + int ret; + + ret = of_property_read_string(dn, "ibm,slot-label", &label); + if (ret) + return NULL; + + if (pnv_pci_get_slot_id(dn, &id)) + return NULL; + + bus = pci_find_bus_by_node(dn); + if (!bus) + return NULL; + + php_slot = kzalloc(sizeof(*php_slot), GFP_KERNEL); + if (!php_slot) + return NULL; + + php_slot->name = kstrdup(label, GFP_KERNEL); + if (!php_slot->name) { + kfree(php_slot); + return NULL; + } + + if (dn->child && PCI_DN(dn->child)) + php_slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn); + else + php_slot->slot_no = -1; /* Placeholder slot */ + + kref_init(&php_slot->kref); + php_slot->state = PNV_PHP_STATE_INITIALIZED; + php_slot->dn = dn; + php_slot->pdev = bus->self; + php_slot->bus = bus; + php_slot->id = id; + php_slot->power_state_check = false; + php_slot->slot.ops = &php_slot_ops; + + INIT_LIST_HEAD(&php_slot->children); + INIT_LIST_HEAD(&php_slot->link); + + return php_slot; +} + +static int pnv_php_register_slot(struct pnv_php_slot *php_slot) +{ + struct pnv_php_slot *parent; + struct device_node *dn = php_slot->dn; + unsigned long flags; + int ret; + + /* Check if the slot is registered or not */ + parent = pnv_php_find_slot(php_slot->dn); + if (parent) { + pnv_php_put_slot(parent); + return -EEXIST; + } + + /* Register PCI slot */ + ret = pci_hp_register(&php_slot->slot, php_slot->bus, + php_slot->slot_no, php_slot->name); + if (ret) { + SLOT_WARN(php_slot, "Error %d registering slot\n", ret); + return ret; + } + + /* Attach to the parent's child list or global list */ + while ((dn = of_get_parent(dn))) { + if (!PCI_DN(dn)) { + of_node_put(dn); + break; + } + + parent = pnv_php_find_slot(dn); + if (parent) { + of_node_put(dn); + break; + } + + of_node_put(dn); + } + + spin_lock_irqsave(&pnv_php_lock, flags); + php_slot->parent = parent; + if (parent) + list_add_tail(&php_slot->link, &parent->children); + else + list_add_tail(&php_slot->link, &pnv_php_slot_list); + spin_unlock_irqrestore(&pnv_php_lock, flags); + + php_slot->state = PNV_PHP_STATE_REGISTERED; + 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) { + SLOT_WARN(php_slot, "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); + + pci_dbg(pdev, "PCI slot [%s]: HP int! DLAct: %d, PresDet: %d\n", + php_slot->name, + !!(sts & PCI_EXP_SLTSTA_DLLSC), + !!(sts & PCI_EXP_SLTSTA_PDC)); + + if (sts & PCI_EXP_SLTSTA_DLLSC) { + pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lsts); + added = !!(lsts & PCI_EXP_LNKSTA_DLLLA); + } else if (!(php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) && + (sts & PCI_EXP_SLTSTA_PDC)) { + ret = pnv_pci_get_presence_state(php_slot->id, &presence); + if (ret) { + SLOT_WARN(php_slot, + "PCI slot [%s] error %d getting presence (0x%04x), to retry the operation.\n", + php_slot->name, ret, sts); + return IRQ_HANDLED; + } + + added = !!(presence == OPAL_PCI_SLOT_PRESENT); + } else { + pci_dbg(pdev, "PCI slot [%s]: Spurious IRQ?\n", php_slot->name); + 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_mark_isolated(pe); + 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) { + SLOT_WARN(php_slot, + "PCI slot [%s] missed hotplug event 0x%04x\n", + php_slot->name, sts); + return IRQ_HANDLED; + } + + pci_info(pdev, "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; + u32 broken_pdc = 0; + u16 sts, ctrl; + int ret; + + /* Allocate workqueue */ + php_slot->wq = alloc_workqueue("pciehp-%s", 0, 0, php_slot->name); + if (!php_slot->wq) { + SLOT_WARN(php_slot, "Cannot alloc workqueue\n"); + pnv_php_disable_irq(php_slot, true); + return; + } + + /* Check PDC (Presence Detection Change) is broken or not */ + ret = of_property_read_u32(php_slot->dn, "ibm,slot-broken-pdc", + &broken_pdc); + if (!ret && broken_pdc) + php_slot->flags |= PNV_PHP_FLAG_BROKEN_PDC; + + /* Clear pending interrupts */ + pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &sts); + if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) + sts |= PCI_EXP_SLTSTA_DLLSC; + else + 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, true); + SLOT_WARN(php_slot, "Error %d enabling IRQ %d\n", ret, irq); + return; + } + + /* Enable the interrupts */ + pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &ctrl); + if (php_slot->flags & PNV_PHP_FLAG_BROKEN_PDC) { + ctrl &= ~PCI_EXP_SLTCTL_PDCE; + ctrl |= (PCI_EXP_SLTCTL_HPIE | + PCI_EXP_SLTCTL_DLLSCE); + } else { + 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; + + /* + * The MSI/MSIx interrupt might have been occupied by other + * drivers. Don't populate the surprise hotplug capability + * in that case. + */ + if (pci_dev_msi_enabled(pdev)) + return; + + ret = pci_enable_device(pdev); + if (ret) { + SLOT_WARN(php_slot, "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; + u32 prop32; + int ret; + + /* Check if it's hotpluggable slot */ + ret = of_property_read_u32(dn, "ibm,slot-pluggable", &prop32); + if (ret || !prop32) + return -ENXIO; + + ret = of_property_read_u32(dn, "ibm,reset-by-firmware", &prop32); + if (ret || !prop32) + return -ENXIO; + + php_slot = pnv_php_alloc_slot(dn); + if (!php_slot) + return -ENODEV; + + ret = pnv_php_register_slot(php_slot); + if (ret) + goto free_slot; + + ret = pnv_php_enable(php_slot, false); + if (ret) + goto unregister_slot; + + /* Enable interrupt if the slot supports surprise hotplug */ + ret = of_property_read_u32(dn, "ibm,slot-surprise-pluggable", &prop32); + if (!ret && prop32) + pnv_php_enable_irq(php_slot); + + return 0; + +unregister_slot: + pnv_php_unregister_one(php_slot->dn); +free_slot: + pnv_php_put_slot(php_slot); + return ret; +} + +static void pnv_php_register(struct device_node *dn) +{ + struct device_node *child; + + /* + * The parent slots should be registered before their + * child slots. + */ + for_each_child_of_node(dn, child) { + pnv_php_register_one(child); + pnv_php_register(child); + } +} + +static void pnv_php_unregister_one(struct device_node *dn) +{ + struct pnv_php_slot *php_slot; + + php_slot = pnv_php_find_slot(dn); + if (!php_slot) + return; + + php_slot->state = PNV_PHP_STATE_OFFLINE; + pci_hp_deregister(&php_slot->slot); + pnv_php_release(php_slot); + pnv_php_put_slot(php_slot); +} + +static void pnv_php_unregister(struct device_node *dn) +{ + struct device_node *child; + + /* The child slots should go before their parent slots */ + for_each_child_of_node(dn, child) { + pnv_php_unregister(child); + pnv_php_unregister_one(child); + } +} + +static int __init pnv_php_init(void) +{ + struct device_node *dn; + + pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); + for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") + pnv_php_register(dn); + + for_each_compatible_node(dn, NULL, "ibm,ioda3-phb") + pnv_php_register(dn); + + for_each_compatible_node(dn, NULL, "ibm,ioda2-npu2-opencapi-phb") + pnv_php_register_one(dn); /* slot directly under the PHB */ + return 0; +} + +static void __exit pnv_php_exit(void) +{ + struct device_node *dn; + + for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") + pnv_php_unregister(dn); + + for_each_compatible_node(dn, NULL, "ibm,ioda3-phb") + pnv_php_unregister(dn); + + for_each_compatible_node(dn, NULL, "ibm,ioda2-npu2-opencapi-phb") + pnv_php_unregister_one(dn); /* slot directly under the PHB */ +} + +module_init(pnv_php_init); +module_exit(pnv_php_exit); + +MODULE_VERSION(DRIVER_VERSION); +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR(DRIVER_AUTHOR); +MODULE_DESCRIPTION(DRIVER_DESC); |