summaryrefslogtreecommitdiffstats
path: root/drivers/pci/hotplug/pnv_php.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /drivers/pci/hotplug/pnv_php.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pci/hotplug/pnv_php.c')
-rw-r--r--drivers/pci/hotplug/pnv_php.c965
1 files changed, 965 insertions, 0 deletions
diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c
new file mode 100644
index 000000000..3276a5e4c
--- /dev/null
+++ b/drivers/pci/hotplug/pnv_php.c
@@ -0,0 +1,965 @@
+// 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 <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"
+
+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;
+ int refcount;
+
+ for_each_child_of_node(parent, dn) {
+ pnv_php_detach_device_nodes(dn);
+
+ of_node_put(dn);
+ refcount = kref_read(&dn->kobj.kref);
+ if (refcount != 1)
+ pr_warn("Invalid refcount %d on <%pOF>\n",
+ refcount, 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) {
+ pci_warn(php_slot->pdev, "Error %d getting FDT blob\n", ret);
+ goto free_fdt1;
+ }
+
+ fdt = kzalloc(fdt_totalsize(fdt1), GFP_KERNEL);
+ if (!fdt) {
+ ret = -ENOMEM;
+ goto free_fdt1;
+ }
+
+ /* Unflatten device tree blob */
+ memcpy(fdt, fdt1, fdt_totalsize(fdt1));
+ dt = of_fdt_unflatten_tree(fdt, php_slot->dn, NULL);
+ if (!dt) {
+ ret = -EINVAL;
+ pci_warn(php_slot->pdev, "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);
+ pci_warn(php_slot->pdev, "Error %d populating changeset\n",
+ ret);
+ goto free_dt;
+ }
+
+ php_slot->dn->child = NULL;
+ ret = of_changeset_apply(&php_slot->ocs);
+ if (ret) {
+ pci_warn(php_slot->pdev, "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;
+}
+
+int pnv_php_set_slot_power_state(struct hotplug_slot *slot,
+ uint8_t state)
+{
+ struct pnv_php_slot *php_slot = slot->private;
+ 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 ||
+ be64_to_cpu(msg.params[3]) != OPAL_SUCCESS) {
+ pci_warn(php_slot->pdev, "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;
+ }
+ } else if (ret < 0) {
+ pci_warn(php_slot->pdev, "Error %d powering %s\n",
+ ret, (state == OPAL_PCI_SLOT_POWER_ON) ? "on" : "off");
+ return ret;
+ }
+
+ 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;
+}
+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 = slot->private;
+ 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) {
+ pci_warn(php_slot->pdev, "Error %d getting power status\n",
+ ret);
+ } else {
+ *state = power_state;
+ slot->info->power_status = power_state;
+ }
+
+ return 0;
+}
+
+static int pnv_php_get_adapter_state(struct hotplug_slot *slot, u8 *state)
+{
+ struct pnv_php_slot *php_slot = slot->private;
+ 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;
+ slot->info->adapter_status = presence;
+ ret = 0;
+ } else {
+ pci_warn(php_slot->pdev, "Error %d getting presence\n", ret);
+ }
+
+ return ret;
+}
+
+static int pnv_php_set_attention_state(struct hotplug_slot *slot, u8 state)
+{
+ /* FIXME: Make it real once firmware supports it */
+ slot->info->attention_status = state;
+
+ 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_enable_slot(struct hotplug_slot *slot)
+{
+ struct pnv_php_slot *php_slot = container_of(slot,
+ struct 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 = slot->private;
+ int ret;
+
+ if (php_slot->state != PNV_PHP_STATE_POPULATED)
+ 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 struct hotplug_slot_ops php_slot_ops = {
+ .get_power_status = pnv_php_get_power_state,
+ .get_adapter_status = pnv_php_get_adapter_state,
+ .set_attention_status = pnv_php_set_attention_state,
+ .enable_slot = pnv_php_enable_slot,
+ .disable_slot = pnv_php_disable_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;
+ php_slot->slot.info = &php_slot->slot_info;
+ php_slot->slot.private = php_slot;
+
+ 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) {
+ pci_warn(php_slot->pdev, "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) {
+ pci_warn(pdev, "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 (!(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) {
+ pci_warn(pdev, "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 {
+ 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) {
+ pci_warn(pdev, "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) {
+ pci_warn(pdev, "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);
+ pci_warn(pdev, "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) {
+ pci_warn(pdev, "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);
+
+ 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);
+}
+
+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);