| Message ID | 1446642770-4681-51-git-send-email-gwshan@linux.vnet.ibm.com |
|---|---|
| State | Not Applicable |
| Headers | show |
On 11/05/2015 12:12 AM, Gavin Shan wrote: > This adds standalone driver to support PCI hotplug for PowerPC PowerNV > platform that runs on top of skiboot firmware. The firmware identifies > hotpluggable slots and marked their device tree node with proper > "ibm,slot-pluggable" and "ibm,reset-by-firmware". The driver scans device > tree nodes to create/register PCI hotplug slot accordingly. > > If the skiboot firmware doesn't support slot status retrieval, the PCI > slot device node shouldn't have property "ibm,reset-by-firmware". In > that case, none of valid PCI slots will be detected from device tree. > The skiboot firmware doesn't export the capability to access attention > LEDs yet and it's something for TBD. Few words what we are actually dealing with and how children slots can be hotplugged to parent slots? > > Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> > Acked-by: Bjorn Helgaas <bhelgaas@google.com> > --- > MAINTAINERS | 6 + > drivers/pci/hotplug/Kconfig | 12 + > drivers/pci/hotplug/Makefile | 3 + > drivers/pci/hotplug/pnv_php.c | 866 ++++++++++++++++++++++++++++++++++++++++++ > 4 files changed, 887 insertions(+) > create mode 100644 drivers/pci/hotplug/pnv_php.c > > diff --git a/MAINTAINERS b/MAINTAINERS > index 9f6685f..10088f1 100644 > --- a/MAINTAINERS > +++ b/MAINTAINERS > @@ -7931,6 +7931,12 @@ L: linux-pci@vger.kernel.org > S: Supported > F: Documentation/PCI/pci-error-recovery.txt > > +PCI HOTPLUG DRIVER FOR POWERNV PLATFORM > +M: Gavin Shan <gwshan@linux.vnet.ibm.com> > +L: linux-pci@vger.kernel.org > +S: Supported > +F: drivers/pci/hotplug/pnv_php.c > + > PCI SUBSYSTEM > M: Bjorn Helgaas <bhelgaas@google.com> > L: linux-pci@vger.kernel.org > diff --git a/drivers/pci/hotplug/Kconfig b/drivers/pci/hotplug/Kconfig > index df8caec..167c8ce 100644 > --- a/drivers/pci/hotplug/Kconfig > +++ b/drivers/pci/hotplug/Kconfig > @@ -113,6 +113,18 @@ config HOTPLUG_PCI_SHPC > > When in doubt, say N. > > +config HOTPLUG_PCI_POWERNV > + tristate "PowerPC PowerNV PCI Hotplug driver" > + depends on PPC_POWERNV && EEH > + help > + Say Y here if you run PowerPC PowerNV platform that supports > + PCI Hotplug > + > + To compile this driver as a module, choose M here: the > + module will be called pnv-php. > + > + When in doubt, say N. > + > config HOTPLUG_PCI_RPA > tristate "RPA PCI Hotplug driver" > depends on PPC_PSERIES && EEH > diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile > index b616e75..e33cdda 100644 > --- a/drivers/pci/hotplug/Makefile > +++ b/drivers/pci/hotplug/Makefile > @@ -14,6 +14,7 @@ obj-$(CONFIG_HOTPLUG_PCI_PCIE) += pciehp.o > obj-$(CONFIG_HOTPLUG_PCI_CPCI_ZT5550) += cpcihp_zt5550.o > obj-$(CONFIG_HOTPLUG_PCI_CPCI_GENERIC) += cpcihp_generic.o > obj-$(CONFIG_HOTPLUG_PCI_SHPC) += shpchp.o > +obj-$(CONFIG_HOTPLUG_PCI_POWERNV) += pnv-php.o > obj-$(CONFIG_HOTPLUG_PCI_RPA) += rpaphp.o > obj-$(CONFIG_HOTPLUG_PCI_RPA_DLPAR) += rpadlpar_io.o > obj-$(CONFIG_HOTPLUG_PCI_SGI) += sgi_hotplug.o > @@ -50,6 +51,8 @@ ibmphp-objs := ibmphp_core.o \ > acpiphp-objs := acpiphp_core.o \ > acpiphp_glue.o > > +pnv-php-objs := pnv_php.o > + > rpaphp-objs := rpaphp_core.o \ > rpaphp_pci.o \ > rpaphp_slot.o > diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c > new file mode 100644 > index 0000000..415e9b9 > --- /dev/null > +++ b/drivers/pci/hotplug/pnv_php.c > @@ -0,0 +1,866 @@ > +/* > + * PCI Hotplug Driver for PowerPC PowerNV platform. > + * > + * Copyright Gavin Shan, IBM Corporation 2015. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU General Public License as published by > + * the Free Software Foundation; either version 2 of the License, or > + * (at your option) any later version. > + */ > + > +#include <linux/pci.h> > +#include <linux/pci_hotplug.h> > +#include <linux/module.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_slot { > + struct hotplug_slot php_slot; > + struct hotplug_slot_info php_slot_info; > + uint64_t id; > + char *name; > + int slot_no; > + struct kref kref; > + int state; > +#define PNV_PHP_STATE_INIT 0 INITIALIZED > +#define PNV_PHP_STATE_REGISTER 1 REGISTERED > +#define PNV_PHP_STATE_POPULATED 2 This one has "ed" already :) And usually definitions go before the variable which uses them. > + struct device_node *dn; > + struct pci_dev *pdev; > + struct pci_bus *bus; > + bool power_state_check; > + int power_state_confirmed; > +#define PNV_PHP_POWER_CONFIRMED_INVALID 0 > +#define PNV_PHP_POWER_CONFIRMED_SUCCESS 1 > +#define PNV_PHP_POWER_CONFIRMED_FAIL 2 > + struct opal_msg *msg; > + void *fdt; > + void *dt; > + struct of_changeset ocs; > + struct work_struct work; > + wait_queue_head_t queue; > + struct pnv_php_slot *parent; > + struct list_head children; > + struct list_head link; > +}; > + > +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 inline struct pnv_php_slot *pnv_php_get_slot(struct pnv_php_slot *slot) > +{ > + if (slot) { > + kref_get(&slot->kref); > + return slot; > + } > + > + return NULL; > +} > + > +static void pnv_php_free_slot(struct kref *kref) > +{ > + struct pnv_php_slot *slot = container_of(kref, > + struct pnv_php_slot, > + kref); > + > + WARN_ON(!list_empty(&slot->children)); > + kfree(slot->name); > + kfree(slot); > +} > + > +static inline void pnv_php_put_slot(struct pnv_php_slot *slot) > +{ > + if (!slot) > + return; > + > + kref_put(&slot->kref, pnv_php_free_slot); > +} > + > +static struct pnv_php_slot *pnv_php_match(struct device_node *dn, > + struct pnv_php_slot *slot) > +{ > + struct pnv_php_slot *target, *tmp; > + > + if (slot->dn == dn) > + return pnv_php_get_slot(slot); > + > + list_for_each_entry(tmp, &slot->children, link) { > + target = pnv_php_match(dn, tmp); > + if (target) > + return target; > + } > + > + return NULL; > +} > + > +static struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn) > +{ > + struct pnv_php_slot *slot, *tmp; > + unsigned long flags; > + > + spin_lock_irqsave(&pnv_php_lock, flags); > + list_for_each_entry(tmp, &pnv_php_slot_list, link) { > + slot = pnv_php_match(dn, tmp); > + if (slot) { > + spin_unlock_irqrestore(&pnv_php_lock, flags); > + return slot; > + } > + } > + spin_unlock_irqrestore(&pnv_php_lock, flags); > + > + return NULL; > +} > + > +/* > + * 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); > + } > +} > + > +/* > + * Remove all child nodes of the indicated device nodes. The > + * function should remove device nodes in depth-first manner. > + */ > +static int pnv_php_rmv_device_nodes(struct device_node *parent) > +{ > + struct device_node *dn, *child; > + int ret = 0; > + > + for_each_child_of_node(parent, dn) { > + ret = pnv_php_rmv_device_nodes(dn); > + if (ret) > + return ret; > + > + child = of_get_next_child(dn, NULL); > + if (child) { > + of_node_put(child); > + of_node_put(dn); > + pr_err("%s: Alive children of node <%s>\n", > + __func__, of_node_full_name(dn)); > + return -EBUSY; > + } > + > + of_detach_node(dn); > + of_node_put(dn); > + } This loop iterates just once, is this correct? If so, then a loop is not needed here... > + > + return 0; > +} > + > +/* > + * The function processes the message sent by firmware > + * to remove all device tree nodes beneath the slot's > + * nodes and the associated auxiliary data. > + */ > +static void pnv_php_handle_poweroff(struct pnv_php_slot *slot) > +{ > + int ret; > + > + pnv_php_rmv_pdns(slot->dn); > + > + /* > + * If the device sub-tree was created from OF changeset, simply > + * to revert that. Otherwise, the device nodes in the sub-tree > + * need to be iterated and detached. > + */ > + if (slot->fdt) { > + of_changeset_destroy(&slot->ocs); > + kfree(slot->dt); > + kfree(slot->fdt); > + slot->dt = NULL; > + slot->dn->child = NULL; > + slot->fdt = NULL; > + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; > + goto confirm; > + } } else { > + > + ret = pnv_php_rmv_device_nodes(slot->dn); > + if (!ret) { > + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; > + } else { > + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_FAIL; > + dev_warn(&slot->pdev->dev, "Error %d freeing nodes\n", > + ret); Could be one line :) > + } > + } and remove the label below? > +confirm: > + wake_up_interruptible(&slot->queue); > +} > + > +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) > + return ret; > + > + ret = pnv_php_populate_changeset(ocs, child); if (ret) break; may be? > + } > + > + 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 void pnv_php_handle_poweron(struct pnv_php_slot *slot) > +{ > + void *fdt, *dt; > + uint64_t len; > + int confirm = PNV_PHP_POWER_CONFIRMED_SUCCESS; > + int ret; > + > + /* We don't know the FDT blob size. It tries with incremental > + * sized memory chunk. > + */ > + for (len = 0x2000; len <= 0x10000; len += 0x2000) { > + fdt = kzalloc(len, GFP_KERNEL); > + if (!fdt) > + break; > + > + ret = pnv_pci_get_device_tree(slot->dn->phandle, fdt, len); > + if (!ret) > + break; > + > + kfree(fdt); > + } > + > + if (len > 0x10000) { > + dev_warn(&slot->pdev->dev, "Cannot alloc FDT blob\n"); > + goto out; This seems like an error but slot->power_state_confirmed will be set to PNV_PHP_POWER_CONFIRMED_SUCCESS anyway, is that correct? > + } I'd redo the chunk above like this: fdt1 = kzalloc(0x10000); if (!fdt1) goto out; ret = pnv_pci_get_device_tree(slot->dn->phandle, fdt1, 0x10000); if (!ret) goto out; fdt = kzalloc(fdt_totalsize(fdt1)); if (!fdt) goto out; memcpy(fdt, fdt1, fdt_totalsize(fdt1)); kfree(fdt1); This way you end up using less memory after setup has completed. And what is an usual size of the returned blob? > + > + /* Unflatten device tree blob */ > + dt = of_fdt_unflatten_tree(fdt, slot->dn, NULL); > + if (!dt) { > + dev_warn(&slot->pdev->dev, "Cannot unflatten FDT\n"); > + goto free_fdt; > + } > + > + /* Initialize and apply the changeset */ > + of_changeset_init(&slot->ocs); > + ret = pnv_php_populate_changeset(&slot->ocs, slot->dn); > + if (ret) { > + dev_warn(&slot->pdev->dev, "Error %d populating changeset\n", > + ret); > + goto free_dt; > + } > + > + slot->dn->child = NULL; > + ret = of_changeset_apply(&slot->ocs); > + if (ret) { > + dev_warn(&slot->pdev->dev, "Error %d applying changeset\n", > + ret); > + goto destroy_changeset; > + } > + > + /* Add device node firmware data */ > + pnv_php_add_pdns(slot); > + slot->fdt = fdt; > + slot->dt = dt; > + goto out; > + > +destroy_changeset: > + of_changeset_destroy(&slot->ocs); > +free_dt: > + kfree(dt); > + slot->dn->child = NULL; > +free_fdt: > + kfree(fdt); > + confirm = PNV_PHP_POWER_CONFIRMED_FAIL; > +out: > + /* Confirm status change */ > + slot->power_state_confirmed = confirm; > + wake_up_interruptible(&slot->queue); > +} > + > +static void pnv_php_work(struct work_struct *data) > +{ > + struct pnv_php_slot *slot = container_of(data, > + struct pnv_php_slot, work); > + uint64_t event = be64_to_cpu(slot->msg->params[0]); > + > + if (event == OPAL_PCI_SLOT_POWER_OFF) > + pnv_php_handle_poweroff(slot); > + else > + pnv_php_handle_poweron(slot); > + > + pnv_php_put_slot(slot); > +} > + > +static int pnv_php_handle_msg(struct notifier_block *nb, > + unsigned long type, > + void *message) > +{ > + phandle h; > + struct device_node *dn; > + struct pnv_php_slot *slot; > + struct opal_msg *msg = message; > + > + if (type != OPAL_MSG_PCI_HOTPLUG) { > + pr_warn("%s: Invalid message %ld received!\n", > + __func__, type); > + return NOTIFY_DONE; > + } > + > + h = (phandle)be64_to_cpu(msg->params[1]); > + dn = of_find_node_by_phandle(h); > + if (!dn) { > + pr_warn("%s: No device node for phandle 0x%x\n", > + __func__, h); > + return NOTIFY_DONE; > + } > + > + slot = pnv_php_find_slot(dn); > + of_node_put(dn); > + if (!slot) { > + pr_warn("%s: No slot found for node <%s>\n", > + __func__, of_node_full_name(dn)); > + of_node_put(dn); You already put the node 5 lines above, is this correct? > + return NOTIFY_DONE; > + } > + > + slot->msg = msg; > + schedule_work(&slot->work); > + return NOTIFY_OK; > +} > + > +static int pnv_php_set_power_state(struct hotplug_slot *php_slot, u8 state) > +{ > + struct pnv_php_slot *slot = php_slot->private; Most instances of "struct pnv_php_slot" are called "slot". Most instances of "struct hotplug_slot" are called "php_slot". When I read this code, I have to remind myself that a "php_slot" variable (which has "php" in it) is NOT of the type with "php" (i.e. NOT "pnv_php_slot"). I would suggest swapping slot <-> php_slot. > + int ret; > + > + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; > + ret = pnv_pci_set_power_state(slot->id, state); > + if (ret) { > + dev_warn(&slot->pdev->dev, "Error %d powering %s slot\n", > + ret, state ? "on" : "off"); > + return ret; > + } > + > + /* Continue to PCI probing after finalized device-tree. The > + * device-tree might have been updated completely at this > + * point. Thus we don't have to always waiting for that. s/always waiting/wait forever/ ? > + */ > + if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) > + return 0; > + else if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_FAIL) No need in "else" here. > + return -EBUSY; > + > + ret = wait_event_timeout(slot->queue, > + slot->power_state_confirmed, 10 * HZ); The code flow is unclear in this case. The queue is signaled from pnv_php_handle_poweron() which is "work" and scheduled by pnv_php_handle_msg() and it is not obvious what code calls pnv_php_handle_msg(). > + if (!ret) { > + dev_warn(&slot->pdev->dev, "Error %d waiting for power-%s\n", > + ret, state ? "on" : "off"); > + return -EBUSY; > + } > + > + if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) > + return 0; > + > + dev_warn(&slot->pdev->dev, "Error status %d for power-%s\n", > + slot->power_state_confirmed, state ? "on" : "off"); > + return -EBUSY; > +} > + > +static int pnv_php_get_power_state(struct hotplug_slot *php_slot, u8 *state) > +{ > + struct pnv_php_slot *slot = php_slot->private; > + uint8_t power_state; > + 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(slot->id, &power_state); > + if (ret) { > + *state = OPAL_PCI_SLOT_POWER_ON; > + dev_warn(&slot->pdev->dev, "Error %d getting power status\n", > + ret); > + } else { > + *state = power_state; > + php_slot->info->power_status = power_state; > + } > + > + return 0; > +} > + > +static int pnv_php_get_adapter_state(struct hotplug_slot *php_slot, u8 *state) > +{ > + struct pnv_php_slot *slot = php_slot->private; > + uint8_t presence; > + 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(slot->id, &presence); > + if (ret >= 0) { > + *state = presence; > + php_slot->info->adapter_status = presence; > + ret = 0; > + } else { > + *state = OPAL_PCI_SLOT_EMPTY; > + dev_warn(&slot->pdev->dev, "Error %d getting presence\n", > + ret); > + } > + > + return ret; > +} > + > +static int pnv_php_set_attention_state(struct hotplug_slot *php_slot, u8 state) > +{ > + /* FIXME: Make it real once firmware supports it */ > + php_slot->info->attention_status = state; > + > + return 0; > +} > + > +static int pnv_php_enable(struct pnv_php_slot *slot, bool rescan) > +{ > + struct hotplug_slot *php_slot = &slot->php_slot; > + uint8_t presence, power_status; > + int ret; > + > + /* Check if the slot has been configured */ > + if (slot->state != PNV_PHP_STATE_REGISTER) > + return 0; > + > + /* Retrieve slot presence status */ > + ret = php_slot->ops->get_adapter_status(php_slot, &presence); Here and in other places there is no point in dereferencing ops, just call pnv_php_get_adapter_state() here directly as you decided not to have a separate source file for pnv_php_slot. > + if (ret) > + return ret; > + > + /* Proceed if there have nothing behind the slot */ > + if (presence == OPAL_PCI_SLOT_EMPTY) > + goto scan; > + > + /* > + * If we don't detect something behind the slot, we need > + * make sure the power suply to the slot is on. Is this correct - "don't detect" -> "make sure it is on"? > Otherwise, > + * the slot downstream PCIe linkturn should be down. > + * > + * On the first time, we don't change the power status to > + * boost system boot with assumption that the firmware Out of curiosity - does it really boost booting? :) > + * supplies consistent slot power status: empty slot always > + * has its power off and non-empty slot has its power on. > + */ > + if (!slot->power_state_check) { > + slot->power_state_check = true; > + goto scan; > + } > + > + /* Check the power status. Scan the slot if that's already on */ > + ret = php_slot->ops->get_power_status(php_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_power_state(php_slot, OPAL_PCI_SLOT_POWER_ON); > + if (ret) > + return ret; > + > +scan: > + if (presence == OPAL_PCI_SLOT_PRESENT) { > + if (rescan) { > + pci_lock_rescan_remove(); > + pci_add_pci_devices(slot->bus); > + pci_unlock_rescan_remove(); > + } > + > + /* Rescan for child hotpluggable slots */ > + slot->state = PNV_PHP_STATE_POPULATED; > + if (rescan) > + pnv_php_register(slot->dn); The chunk above adds a parent slot (a physical slot) and then scans for children slots (a mighty extended with extra physical slots)? :) > + } else { > + slot->state = PNV_PHP_STATE_POPULATED; > + } > + > + return 0; > +} > + > +static int pnv_php_enable_slot(struct hotplug_slot *php_slot) > +{ > + struct pnv_php_slot *slot = container_of(php_slot, > + struct pnv_php_slot, > + php_slot); > + > + return pnv_php_enable(slot, true); > +} > + > +static int pnv_php_disable_slot(struct hotplug_slot *php_slot) > +{ > + struct pnv_php_slot *slot = php_slot->private; > + uint8_t power_state; > + int ret; > + > + if (slot->state != PNV_PHP_STATE_POPULATED) > + return 0; > + > + /* Remove all devices behind the slot */ > + pci_lock_rescan_remove(); > + pci_remove_pci_devices(slot->bus); > + pci_unlock_rescan_remove(); > + > + /* Detach the child hotpluggable slots */ > + pnv_php_unregister(slot->dn); > + > + /* > + * Check the power status and turn it off if necessary. If we > + * fail to get the power status, the power will be forced to > + * be off. > + */ > + ret = php_slot->ops->get_power_status(php_slot, &power_state); > + if (ret || power_state == OPAL_PCI_SLOT_POWER_ON) { > + ret = pnv_php_set_power_state(php_slot, > + OPAL_PCI_SLOT_POWER_OFF); > + if (ret) > + dev_warn(&slot->pdev->dev, "Error %d powering off\n", > + ret); > + } > + > + /* Update slot state */ > + slot->state = PNV_PHP_STATE_REGISTER; > + return 0; > +} > + > +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 hotplug_slot *hp_slot) > +{ > + struct pnv_php_slot *slot = hp_slot->private; > + unsigned long flags; > + > + /* Remove from global or child list */ > + spin_lock_irqsave(&pnv_php_lock, flags); > + list_del(&slot->link); > + spin_unlock_irqrestore(&pnv_php_lock, flags); > + > + /* Detach from parent */ > + pnv_php_put_slot(slot); > + pnv_php_put_slot(slot->parent); > +} > + > +static int pnv_php_get_slot_id(struct device_node *dn, uint64_t *id) > +{ > + struct device_node *parent = dn; > + const __be64 *prop64; > + const __be32 *prop32; > + > + /* > + * The hotpluggable slot always has a compound Id, which > + * consists of 16-bits PHB Id, 16 bits bus/slot/function > + * number, and compound indicator > + */ > + *id = (0x1ul << 63); > + > + /* Bus/Slot/Function number */ > + prop32 = of_get_property(dn, "reg", NULL); > + if (!prop32) > + return -ENXIO; > + *id |= ((of_read_number(prop32, 1) & 0x00ffff00) << 8); > + > + /* PHB Id */ > + while ((parent = of_get_parent(parent))) { > + if (!PCI_DN(parent)) { > + of_node_put(parent); > + break; > + } > + > + if (!of_device_is_compatible(parent, "ibm,ioda2-phb") && > + !of_device_is_compatible(parent, "ibm,ioda-phb")) { > + of_node_put(parent); > + continue; > + } > + > + prop64 = of_get_property(parent, "ibm,opal-phbid", NULL); > + if (!prop64) { > + of_node_put(parent); > + return -ENXIO; > + } > + > + *id |= be64_to_cpup(prop64); > + of_node_put(parent); > + return 0; > + } > + > + return -ENODEV; > +} > + > +static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn) > +{ > + struct pnv_php_slot *slot; > + struct pci_bus *bus; > + const char *label; > + uint64_t id; > + > + label = of_get_property(dn, "ibm,slot-label", NULL); > + if (!label) > + return NULL; > + > + if (pnv_php_get_slot_id(dn, &id)) > + return NULL; > + > + bus = pci_find_bus_by_node(dn); > + if (!bus) > + return NULL; > + > + slot = kzalloc(sizeof(*slot), GFP_KERNEL); > + if (!slot) > + return NULL; > + > + slot->name = kstrdup(label, GFP_KERNEL); > + if (!slot->name) { > + kfree(slot); > + return NULL; > + } > + > + if (dn->child && PCI_DN(dn->child)) > + slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn); > + else > + slot->slot_no = -1; /* Placeholder slot */ > + > + kref_init(&slot->kref); > + slot->state = PNV_PHP_STATE_INIT; > + slot->dn = dn; > + slot->pdev = bus->self; > + slot->bus = bus; > + slot->id = id; > + slot->power_state_check = false; > + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; > + slot->php_slot.ops = &php_slot_ops; > + slot->php_slot.info = &slot->php_slot_info; > + slot->php_slot.release = pnv_php_release; > + slot->php_slot.private = slot; > + > + INIT_WORK(&slot->work, pnv_php_work); > + init_waitqueue_head(&slot->queue); > + INIT_LIST_HEAD(&slot->children); > + INIT_LIST_HEAD(&slot->link); > + > + return slot; > +} > + > +static int pnv_php_register_slot(struct pnv_php_slot *slot) > +{ > + struct pnv_php_slot *parent; > + struct device_node *dn = slot->dn; > + unsigned long flags; > + int ret; > + > + /* Check if the slot exists or not */ s/exists/is registered/ > + parent = pnv_php_find_slot(slot->dn); > + if (parent) { > + pnv_php_put_slot(parent); > + return -EEXIST; > + } > + > + /* Register PCI slot */ > + ret = pci_hp_register(&slot->php_slot, slot->bus, > + slot->slot_no, slot->name); > + if (ret) { > + dev_warn(&slot->pdev->dev, "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; > + } This is missing here: of_node_put(dn); > + } > + > + spin_lock_irqsave(&pnv_php_lock, flags); > + slot->parent = parent; > + if (parent) > + list_add_tail(&slot->link, &parent->children); > + else > + list_add_tail(&slot->link, &pnv_php_slot_list); > + spin_unlock_irqrestore(&pnv_php_lock, flags); > + > + slot->state = PNV_PHP_STATE_REGISTER; > + return 0; > +} > + > +static int pnv_php_register_one(struct device_node *dn) > +{ > + struct pnv_php_slot *slot; > + const __be32 *prop32; > + int ret; > + > + /* Check if it's hotpluggable slot */ > + prop32 = of_get_property(dn, "ibm,slot-pluggable", NULL); > + if (!prop32 || !of_read_number(prop32, 1)) > + return -ENXIO; > + > + prop32 = of_get_property(dn, "ibm,reset-by-firmware", NULL); > + if (!prop32 || !of_read_number(prop32, 1)) > + return -ENXIO; > + > + slot = pnv_php_alloc_slot(dn); > + if (!slot) > + return -ENODEV; > + > + ret = pnv_php_register_slot(slot); > + if (ret) > + goto free_slot; > + > + ret = pnv_php_enable(slot, false); > + if (ret) > + goto unregister_slot; > + > + return 0; > + > +unregister_slot: > + pnv_php_unregister_one(slot->dn); > +free_slot: > + pnv_php_put_slot(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 *slot; > + > + slot = pnv_php_find_slot(dn); > + if (!slot) > + return; > + > + pnv_php_put_slot(slot); > + pci_hp_deregister(&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 struct notifier_block php_msg_nb = { > + .notifier_call = pnv_php_handle_msg, > + .next = NULL, > + .priority = 0, > +}; > + > +static int __init pnv_php_init(void) > +{ > + struct device_node *dn; > + int ret; > + > + pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); > + > + /* Register hotplug message handler */ > + ret = pnv_pci_hotplug_notifier_register(&php_msg_nb); > + if (ret) { > + pr_warn("%s: Error %d registering hotplug notifier\n", > + __func__, ret); > + return ret; > + } > + > + /* Scan PHB nodes and their children */ > + for_each_compatible_node(dn, NULL, "ibm,ioda-phb") > + pnv_php_register(dn); > + 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,ioda-phb") > + pnv_php_unregister(dn); > + for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") > + pnv_php_unregister(dn); > + > + pnv_pci_hotplug_notifier_unregister(&php_msg_nb); > +} > + > +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); >
On Wed, Nov 18, 2015 at 06:33:08PM +1100, Alexey Kardashevskiy wrote: >On 11/05/2015 12:12 AM, Gavin Shan wrote: >>This adds standalone driver to support PCI hotplug for PowerPC PowerNV >>platform that runs on top of skiboot firmware. The firmware identifies >>hotpluggable slots and marked their device tree node with proper >>"ibm,slot-pluggable" and "ibm,reset-by-firmware". The driver scans device >>tree nodes to create/register PCI hotplug slot accordingly. >> >>If the skiboot firmware doesn't support slot status retrieval, the PCI >>slot device node shouldn't have property "ibm,reset-by-firmware". In >>that case, none of valid PCI slots will be detected from device tree. >>The skiboot firmware doesn't export the capability to access attention >>LEDs yet and it's something for TBD. > > >Few words what we are actually dealing with and how children slots can be >hotplugged to parent slots? > Sure, will do. All comments you gave will be reflected in next revision. Please let me know if you finish the review and I can start the respin for next revision. >>Signed-off-by: Gavin Shan <gwshan@linux.vnet.ibm.com> >>Acked-by: Bjorn Helgaas <bhelgaas@google.com> >>--- >> MAINTAINERS | 6 + >> drivers/pci/hotplug/Kconfig | 12 + >> drivers/pci/hotplug/Makefile | 3 + >> drivers/pci/hotplug/pnv_php.c | 866 ++++++++++++++++++++++++++++++++++++++++++ >> 4 files changed, 887 insertions(+) >> create mode 100644 drivers/pci/hotplug/pnv_php.c >> >>diff --git a/MAINTAINERS b/MAINTAINERS >>index 9f6685f..10088f1 100644 >>--- a/MAINTAINERS >>+++ b/MAINTAINERS >>@@ -7931,6 +7931,12 @@ L: linux-pci@vger.kernel.org >> S: Supported >> F: Documentation/PCI/pci-error-recovery.txt >> >>+PCI HOTPLUG DRIVER FOR POWERNV PLATFORM >>+M: Gavin Shan <gwshan@linux.vnet.ibm.com> >>+L: linux-pci@vger.kernel.org >>+S: Supported >>+F: drivers/pci/hotplug/pnv_php.c >>+ >> PCI SUBSYSTEM >> M: Bjorn Helgaas <bhelgaas@google.com> >> L: linux-pci@vger.kernel.org >>diff --git a/drivers/pci/hotplug/Kconfig b/drivers/pci/hotplug/Kconfig >>index df8caec..167c8ce 100644 >>--- a/drivers/pci/hotplug/Kconfig >>+++ b/drivers/pci/hotplug/Kconfig >>@@ -113,6 +113,18 @@ config HOTPLUG_PCI_SHPC >> >> When in doubt, say N. >> >>+config HOTPLUG_PCI_POWERNV >>+ tristate "PowerPC PowerNV PCI Hotplug driver" >>+ depends on PPC_POWERNV && EEH >>+ help >>+ Say Y here if you run PowerPC PowerNV platform that supports >>+ PCI Hotplug >>+ >>+ To compile this driver as a module, choose M here: the >>+ module will be called pnv-php. >>+ >>+ When in doubt, say N. >>+ >> config HOTPLUG_PCI_RPA >> tristate "RPA PCI Hotplug driver" >> depends on PPC_PSERIES && EEH >>diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile >>index b616e75..e33cdda 100644 >>--- a/drivers/pci/hotplug/Makefile >>+++ b/drivers/pci/hotplug/Makefile >>@@ -14,6 +14,7 @@ obj-$(CONFIG_HOTPLUG_PCI_PCIE) += pciehp.o >> obj-$(CONFIG_HOTPLUG_PCI_CPCI_ZT5550) += cpcihp_zt5550.o >> obj-$(CONFIG_HOTPLUG_PCI_CPCI_GENERIC) += cpcihp_generic.o >> obj-$(CONFIG_HOTPLUG_PCI_SHPC) += shpchp.o >>+obj-$(CONFIG_HOTPLUG_PCI_POWERNV) += pnv-php.o >> obj-$(CONFIG_HOTPLUG_PCI_RPA) += rpaphp.o >> obj-$(CONFIG_HOTPLUG_PCI_RPA_DLPAR) += rpadlpar_io.o >> obj-$(CONFIG_HOTPLUG_PCI_SGI) += sgi_hotplug.o >>@@ -50,6 +51,8 @@ ibmphp-objs := ibmphp_core.o \ >> acpiphp-objs := acpiphp_core.o \ >> acpiphp_glue.o >> >>+pnv-php-objs := pnv_php.o >>+ >> rpaphp-objs := rpaphp_core.o \ >> rpaphp_pci.o \ >> rpaphp_slot.o >>diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c >>new file mode 100644 >>index 0000000..415e9b9 >>--- /dev/null >>+++ b/drivers/pci/hotplug/pnv_php.c >>@@ -0,0 +1,866 @@ >>+/* >>+ * PCI Hotplug Driver for PowerPC PowerNV platform. >>+ * >>+ * Copyright Gavin Shan, IBM Corporation 2015. >>+ * >>+ * This program is free software; you can redistribute it and/or modify >>+ * it under the terms of the GNU General Public License as published by >>+ * the Free Software Foundation; either version 2 of the License, or >>+ * (at your option) any later version. >>+ */ >>+ >>+#include <linux/pci.h> >>+#include <linux/pci_hotplug.h> >>+#include <linux/module.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_slot { >>+ struct hotplug_slot php_slot; >>+ struct hotplug_slot_info php_slot_info; >>+ uint64_t id; >>+ char *name; >>+ int slot_no; >>+ struct kref kref; >>+ int state; >>+#define PNV_PHP_STATE_INIT 0 > >INITIALIZED > >>+#define PNV_PHP_STATE_REGISTER 1 > >REGISTERED > > >>+#define PNV_PHP_STATE_POPULATED 2 > >This one has "ed" already :) > >And usually definitions go before the variable which uses them. > >>+ struct device_node *dn; >>+ struct pci_dev *pdev; >>+ struct pci_bus *bus; >>+ bool power_state_check; >>+ int power_state_confirmed; >>+#define PNV_PHP_POWER_CONFIRMED_INVALID 0 >>+#define PNV_PHP_POWER_CONFIRMED_SUCCESS 1 >>+#define PNV_PHP_POWER_CONFIRMED_FAIL 2 >>+ struct opal_msg *msg; >>+ void *fdt; >>+ void *dt; >>+ struct of_changeset ocs; >>+ struct work_struct work; >>+ wait_queue_head_t queue; >>+ struct pnv_php_slot *parent; >>+ struct list_head children; >>+ struct list_head link; >>+}; >>+ >>+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 inline struct pnv_php_slot *pnv_php_get_slot(struct pnv_php_slot *slot) >>+{ >>+ if (slot) { >>+ kref_get(&slot->kref); >>+ return slot; >>+ } >>+ >>+ return NULL; >>+} >>+ >>+static void pnv_php_free_slot(struct kref *kref) >>+{ >>+ struct pnv_php_slot *slot = container_of(kref, >>+ struct pnv_php_slot, >>+ kref); >>+ >>+ WARN_ON(!list_empty(&slot->children)); >>+ kfree(slot->name); >>+ kfree(slot); >>+} >>+ >>+static inline void pnv_php_put_slot(struct pnv_php_slot *slot) >>+{ >>+ if (!slot) >>+ return; >>+ >>+ kref_put(&slot->kref, pnv_php_free_slot); >>+} >>+ >>+static struct pnv_php_slot *pnv_php_match(struct device_node *dn, >>+ struct pnv_php_slot *slot) >>+{ >>+ struct pnv_php_slot *target, *tmp; >>+ >>+ if (slot->dn == dn) >>+ return pnv_php_get_slot(slot); >>+ >>+ list_for_each_entry(tmp, &slot->children, link) { >>+ target = pnv_php_match(dn, tmp); >>+ if (target) >>+ return target; >>+ } >>+ >>+ return NULL; >>+} >>+ >>+static struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn) >>+{ >>+ struct pnv_php_slot *slot, *tmp; >>+ unsigned long flags; >>+ >>+ spin_lock_irqsave(&pnv_php_lock, flags); >>+ list_for_each_entry(tmp, &pnv_php_slot_list, link) { >>+ slot = pnv_php_match(dn, tmp); >>+ if (slot) { >>+ spin_unlock_irqrestore(&pnv_php_lock, flags); >>+ return slot; >>+ } >>+ } >>+ spin_unlock_irqrestore(&pnv_php_lock, flags); >>+ >>+ return NULL; >>+} >>+ >>+/* >>+ * 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); >>+ } >>+} >>+ >>+/* >>+ * Remove all child nodes of the indicated device nodes. The >>+ * function should remove device nodes in depth-first manner. >>+ */ >>+static int pnv_php_rmv_device_nodes(struct device_node *parent) >>+{ >>+ struct device_node *dn, *child; >>+ int ret = 0; >>+ >>+ for_each_child_of_node(parent, dn) { >>+ ret = pnv_php_rmv_device_nodes(dn); >>+ if (ret) >>+ return ret; >>+ >>+ child = of_get_next_child(dn, NULL); >>+ if (child) { >>+ of_node_put(child); >>+ of_node_put(dn); >>+ pr_err("%s: Alive children of node <%s>\n", >>+ __func__, of_node_full_name(dn)); >>+ return -EBUSY; >>+ } >>+ >>+ of_detach_node(dn); >>+ of_node_put(dn); >>+ } > > >This loop iterates just once, is this correct? If so, then a loop is not >needed here... > > >>+ >>+ return 0; >>+} >>+ >>+/* >>+ * The function processes the message sent by firmware >>+ * to remove all device tree nodes beneath the slot's >>+ * nodes and the associated auxiliary data. >>+ */ >>+static void pnv_php_handle_poweroff(struct pnv_php_slot *slot) >>+{ >>+ int ret; >>+ >>+ pnv_php_rmv_pdns(slot->dn); >>+ >>+ /* >>+ * If the device sub-tree was created from OF changeset, simply >>+ * to revert that. Otherwise, the device nodes in the sub-tree >>+ * need to be iterated and detached. >>+ */ >>+ if (slot->fdt) { >>+ of_changeset_destroy(&slot->ocs); >>+ kfree(slot->dt); >>+ kfree(slot->fdt); >>+ slot->dt = NULL; >>+ slot->dn->child = NULL; >>+ slot->fdt = NULL; >>+ slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; >>+ goto confirm; >>+ } > >} else { > >>+ >>+ ret = pnv_php_rmv_device_nodes(slot->dn); >>+ if (!ret) { >>+ slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; >>+ } else { >>+ slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_FAIL; >>+ dev_warn(&slot->pdev->dev, "Error %d freeing nodes\n", >>+ ret); > >Could be one line :) > > >>+ } >>+ > >} >and remove the label below? > > >>+confirm: > > >>+ wake_up_interruptible(&slot->queue); >>+} >>+ >>+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) >>+ return ret; >>+ >>+ ret = pnv_php_populate_changeset(ocs, child); > >if (ret) break; may be? > > >>+ } >>+ >>+ 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 void pnv_php_handle_poweron(struct pnv_php_slot *slot) >>+{ >>+ void *fdt, *dt; >>+ uint64_t len; >>+ int confirm = PNV_PHP_POWER_CONFIRMED_SUCCESS; >>+ int ret; >>+ >>+ /* We don't know the FDT blob size. It tries with incremental >>+ * sized memory chunk. >>+ */ >>+ for (len = 0x2000; len <= 0x10000; len += 0x2000) { >>+ fdt = kzalloc(len, GFP_KERNEL); >>+ if (!fdt) >>+ break; >>+ >>+ ret = pnv_pci_get_device_tree(slot->dn->phandle, fdt, len); >>+ if (!ret) >>+ break; >>+ >>+ kfree(fdt); >>+ } >>+ >>+ if (len > 0x10000) { >>+ dev_warn(&slot->pdev->dev, "Cannot alloc FDT blob\n"); >>+ goto out; > >This seems like an error but slot->power_state_confirmed will be set to >PNV_PHP_POWER_CONFIRMED_SUCCESS anyway, is that correct? > > >>+ } > >I'd redo the chunk above like this: > >fdt1 = kzalloc(0x10000); >if (!fdt1) > goto out; >ret = pnv_pci_get_device_tree(slot->dn->phandle, fdt1, 0x10000); >if (!ret) > goto out; >fdt = kzalloc(fdt_totalsize(fdt1)); >if (!fdt) > goto out; >memcpy(fdt, fdt1, fdt_totalsize(fdt1)); >kfree(fdt1); > > >This way you end up using less memory after setup has completed. > >And what is an usual size of the returned blob? > > >>+ >>+ /* Unflatten device tree blob */ >>+ dt = of_fdt_unflatten_tree(fdt, slot->dn, NULL); >>+ if (!dt) { >>+ dev_warn(&slot->pdev->dev, "Cannot unflatten FDT\n"); >>+ goto free_fdt; >>+ } >>+ >>+ /* Initialize and apply the changeset */ >>+ of_changeset_init(&slot->ocs); >>+ ret = pnv_php_populate_changeset(&slot->ocs, slot->dn); >>+ if (ret) { >>+ dev_warn(&slot->pdev->dev, "Error %d populating changeset\n", >>+ ret); >>+ goto free_dt; >>+ } >>+ >>+ slot->dn->child = NULL; >>+ ret = of_changeset_apply(&slot->ocs); >>+ if (ret) { >>+ dev_warn(&slot->pdev->dev, "Error %d applying changeset\n", >>+ ret); >>+ goto destroy_changeset; >>+ } >>+ >>+ /* Add device node firmware data */ >>+ pnv_php_add_pdns(slot); >>+ slot->fdt = fdt; >>+ slot->dt = dt; >>+ goto out; >>+ >>+destroy_changeset: >>+ of_changeset_destroy(&slot->ocs); >>+free_dt: >>+ kfree(dt); >>+ slot->dn->child = NULL; >>+free_fdt: >>+ kfree(fdt); >>+ confirm = PNV_PHP_POWER_CONFIRMED_FAIL; >>+out: >>+ /* Confirm status change */ >>+ slot->power_state_confirmed = confirm; >>+ wake_up_interruptible(&slot->queue); >>+} >>+ >>+static void pnv_php_work(struct work_struct *data) >>+{ >>+ struct pnv_php_slot *slot = container_of(data, >>+ struct pnv_php_slot, work); >>+ uint64_t event = be64_to_cpu(slot->msg->params[0]); >>+ >>+ if (event == OPAL_PCI_SLOT_POWER_OFF) >>+ pnv_php_handle_poweroff(slot); >>+ else >>+ pnv_php_handle_poweron(slot); >>+ >>+ pnv_php_put_slot(slot); >>+} >>+ >>+static int pnv_php_handle_msg(struct notifier_block *nb, >>+ unsigned long type, >>+ void *message) >>+{ >>+ phandle h; >>+ struct device_node *dn; >>+ struct pnv_php_slot *slot; >>+ struct opal_msg *msg = message; >>+ >>+ if (type != OPAL_MSG_PCI_HOTPLUG) { >>+ pr_warn("%s: Invalid message %ld received!\n", >>+ __func__, type); >>+ return NOTIFY_DONE; >>+ } >>+ >>+ h = (phandle)be64_to_cpu(msg->params[1]); >>+ dn = of_find_node_by_phandle(h); >>+ if (!dn) { >>+ pr_warn("%s: No device node for phandle 0x%x\n", >>+ __func__, h); >>+ return NOTIFY_DONE; >>+ } >>+ >>+ slot = pnv_php_find_slot(dn); >>+ of_node_put(dn); >>+ if (!slot) { >>+ pr_warn("%s: No slot found for node <%s>\n", >>+ __func__, of_node_full_name(dn)); >>+ of_node_put(dn); > >You already put the node 5 lines above, is this correct? > >>+ return NOTIFY_DONE; >>+ } >>+ >>+ slot->msg = msg; >>+ schedule_work(&slot->work); >>+ return NOTIFY_OK; >>+} >>+ >>+static int pnv_php_set_power_state(struct hotplug_slot *php_slot, u8 state) >>+{ >>+ struct pnv_php_slot *slot = php_slot->private; > > >Most instances of "struct pnv_php_slot" are called "slot". >Most instances of "struct hotplug_slot" are called "php_slot". > >When I read this code, I have to remind myself that a "php_slot" variable >(which has "php" in it) is NOT of the type with "php" (i.e. NOT >"pnv_php_slot"). > >I would suggest swapping slot <-> php_slot. > > >>+ int ret; >>+ >>+ slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; >>+ ret = pnv_pci_set_power_state(slot->id, state); >>+ if (ret) { >>+ dev_warn(&slot->pdev->dev, "Error %d powering %s slot\n", >>+ ret, state ? "on" : "off"); >>+ return ret; >>+ } >>+ >>+ /* Continue to PCI probing after finalized device-tree. The >>+ * device-tree might have been updated completely at this >>+ * point. Thus we don't have to always waiting for that. > >s/always waiting/wait forever/ ? > >>+ */ >>+ if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) >>+ return 0; >>+ else if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_FAIL) > > >No need in "else" here. > > >>+ return -EBUSY; >>+ >>+ ret = wait_event_timeout(slot->queue, >>+ slot->power_state_confirmed, 10 * HZ); > >The code flow is unclear in this case. > >The queue is signaled from pnv_php_handle_poweron() which is "work" and >scheduled by pnv_php_handle_msg() and it is not obvious what code calls >pnv_php_handle_msg(). > > > >>+ if (!ret) { >>+ dev_warn(&slot->pdev->dev, "Error %d waiting for power-%s\n", >>+ ret, state ? "on" : "off"); >>+ return -EBUSY; >>+ } >>+ >>+ if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) >>+ return 0; >>+ >>+ dev_warn(&slot->pdev->dev, "Error status %d for power-%s\n", >>+ slot->power_state_confirmed, state ? "on" : "off"); >>+ return -EBUSY; >>+} >>+ >>+static int pnv_php_get_power_state(struct hotplug_slot *php_slot, u8 *state) >>+{ >>+ struct pnv_php_slot *slot = php_slot->private; >>+ uint8_t power_state; >>+ 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(slot->id, &power_state); >>+ if (ret) { >>+ *state = OPAL_PCI_SLOT_POWER_ON; >>+ dev_warn(&slot->pdev->dev, "Error %d getting power status\n", >>+ ret); >>+ } else { >>+ *state = power_state; >>+ php_slot->info->power_status = power_state; >>+ } >>+ >>+ return 0; >>+} >>+ >>+static int pnv_php_get_adapter_state(struct hotplug_slot *php_slot, u8 *state) >>+{ >>+ struct pnv_php_slot *slot = php_slot->private; >>+ uint8_t presence; >>+ 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(slot->id, &presence); >>+ if (ret >= 0) { >>+ *state = presence; >>+ php_slot->info->adapter_status = presence; >>+ ret = 0; >>+ } else { >>+ *state = OPAL_PCI_SLOT_EMPTY; >>+ dev_warn(&slot->pdev->dev, "Error %d getting presence\n", >>+ ret); >>+ } >>+ >>+ return ret; >>+} >>+ >>+static int pnv_php_set_attention_state(struct hotplug_slot *php_slot, u8 state) >>+{ >>+ /* FIXME: Make it real once firmware supports it */ >>+ php_slot->info->attention_status = state; >>+ >>+ return 0; >>+} >>+ >>+static int pnv_php_enable(struct pnv_php_slot *slot, bool rescan) >>+{ >>+ struct hotplug_slot *php_slot = &slot->php_slot; >>+ uint8_t presence, power_status; >>+ int ret; >>+ >>+ /* Check if the slot has been configured */ >>+ if (slot->state != PNV_PHP_STATE_REGISTER) >>+ return 0; >>+ >>+ /* Retrieve slot presence status */ >>+ ret = php_slot->ops->get_adapter_status(php_slot, &presence); > > >Here and in other places there is no point in dereferencing ops, just call >pnv_php_get_adapter_state() here directly as you decided not to have a >separate source file for pnv_php_slot. > > >>+ if (ret) >>+ return ret; >>+ >>+ /* Proceed if there have nothing behind the slot */ >>+ if (presence == OPAL_PCI_SLOT_EMPTY) >>+ goto scan; >>+ >>+ /* >>+ * If we don't detect something behind the slot, we need >>+ * make sure the power suply to the slot is on. > >Is this correct - "don't detect" -> "make sure it is on"? > > >>Otherwise, >>+ * the slot downstream PCIe linkturn should be down. >>+ * >>+ * On the first time, we don't change the power status to >>+ * boost system boot with assumption that the firmware > >Out of curiosity - does it really boost booting? :) > > >>+ * supplies consistent slot power status: empty slot always >>+ * has its power off and non-empty slot has its power on. >>+ */ >>+ if (!slot->power_state_check) { >>+ slot->power_state_check = true; >>+ goto scan; >>+ } >>+ >>+ /* Check the power status. Scan the slot if that's already on */ >>+ ret = php_slot->ops->get_power_status(php_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_power_state(php_slot, OPAL_PCI_SLOT_POWER_ON); >>+ if (ret) >>+ return ret; >>+ >>+scan: >>+ if (presence == OPAL_PCI_SLOT_PRESENT) { >>+ if (rescan) { >>+ pci_lock_rescan_remove(); >>+ pci_add_pci_devices(slot->bus); >>+ pci_unlock_rescan_remove(); >>+ } >>+ >>+ /* Rescan for child hotpluggable slots */ >>+ slot->state = PNV_PHP_STATE_POPULATED; >>+ if (rescan) >>+ pnv_php_register(slot->dn); > > >The chunk above adds a parent slot (a physical slot) and then scans for >children slots (a mighty extended with extra physical slots)? :) > > >>+ } else { >>+ slot->state = PNV_PHP_STATE_POPULATED; >>+ } >>+ >>+ return 0; >>+} >>+ >>+static int pnv_php_enable_slot(struct hotplug_slot *php_slot) >>+{ >>+ struct pnv_php_slot *slot = container_of(php_slot, >>+ struct pnv_php_slot, >>+ php_slot); >>+ >>+ return pnv_php_enable(slot, true); >>+} >>+ >>+static int pnv_php_disable_slot(struct hotplug_slot *php_slot) >>+{ >>+ struct pnv_php_slot *slot = php_slot->private; >>+ uint8_t power_state; >>+ int ret; >>+ >>+ if (slot->state != PNV_PHP_STATE_POPULATED) >>+ return 0; >>+ >>+ /* Remove all devices behind the slot */ >>+ pci_lock_rescan_remove(); >>+ pci_remove_pci_devices(slot->bus); >>+ pci_unlock_rescan_remove(); >>+ >>+ /* Detach the child hotpluggable slots */ >>+ pnv_php_unregister(slot->dn); >>+ >>+ /* >>+ * Check the power status and turn it off if necessary. If we >>+ * fail to get the power status, the power will be forced to >>+ * be off. >>+ */ >>+ ret = php_slot->ops->get_power_status(php_slot, &power_state); >>+ if (ret || power_state == OPAL_PCI_SLOT_POWER_ON) { >>+ ret = pnv_php_set_power_state(php_slot, >>+ OPAL_PCI_SLOT_POWER_OFF); >>+ if (ret) >>+ dev_warn(&slot->pdev->dev, "Error %d powering off\n", >>+ ret); >>+ } >>+ >>+ /* Update slot state */ >>+ slot->state = PNV_PHP_STATE_REGISTER; >>+ return 0; >>+} >>+ >>+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 hotplug_slot *hp_slot) >>+{ >>+ struct pnv_php_slot *slot = hp_slot->private; >>+ unsigned long flags; >>+ >>+ /* Remove from global or child list */ >>+ spin_lock_irqsave(&pnv_php_lock, flags); >>+ list_del(&slot->link); >>+ spin_unlock_irqrestore(&pnv_php_lock, flags); >>+ >>+ /* Detach from parent */ >>+ pnv_php_put_slot(slot); >>+ pnv_php_put_slot(slot->parent); >>+} >>+ >>+static int pnv_php_get_slot_id(struct device_node *dn, uint64_t *id) >>+{ >>+ struct device_node *parent = dn; >>+ const __be64 *prop64; >>+ const __be32 *prop32; >>+ >>+ /* >>+ * The hotpluggable slot always has a compound Id, which >>+ * consists of 16-bits PHB Id, 16 bits bus/slot/function >>+ * number, and compound indicator >>+ */ >>+ *id = (0x1ul << 63); >>+ >>+ /* Bus/Slot/Function number */ >>+ prop32 = of_get_property(dn, "reg", NULL); >>+ if (!prop32) >>+ return -ENXIO; >>+ *id |= ((of_read_number(prop32, 1) & 0x00ffff00) << 8); >>+ >>+ /* PHB Id */ >>+ while ((parent = of_get_parent(parent))) { >>+ if (!PCI_DN(parent)) { >>+ of_node_put(parent); >>+ break; >>+ } >>+ >>+ if (!of_device_is_compatible(parent, "ibm,ioda2-phb") && >>+ !of_device_is_compatible(parent, "ibm,ioda-phb")) { >>+ of_node_put(parent); >>+ continue; >>+ } >>+ >>+ prop64 = of_get_property(parent, "ibm,opal-phbid", NULL); >>+ if (!prop64) { >>+ of_node_put(parent); >>+ return -ENXIO; >>+ } >>+ >>+ *id |= be64_to_cpup(prop64); >>+ of_node_put(parent); >>+ return 0; >>+ } >>+ >>+ return -ENODEV; >>+} >>+ >>+static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn) >>+{ >>+ struct pnv_php_slot *slot; >>+ struct pci_bus *bus; >>+ const char *label; >>+ uint64_t id; >>+ >>+ label = of_get_property(dn, "ibm,slot-label", NULL); >>+ if (!label) >>+ return NULL; >>+ >>+ if (pnv_php_get_slot_id(dn, &id)) >>+ return NULL; >>+ >>+ bus = pci_find_bus_by_node(dn); >>+ if (!bus) >>+ return NULL; >>+ >>+ slot = kzalloc(sizeof(*slot), GFP_KERNEL); >>+ if (!slot) >>+ return NULL; >>+ >>+ slot->name = kstrdup(label, GFP_KERNEL); >>+ if (!slot->name) { >>+ kfree(slot); >>+ return NULL; >>+ } >>+ >>+ if (dn->child && PCI_DN(dn->child)) >>+ slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn); >>+ else >>+ slot->slot_no = -1; /* Placeholder slot */ >>+ >>+ kref_init(&slot->kref); >>+ slot->state = PNV_PHP_STATE_INIT; >>+ slot->dn = dn; >>+ slot->pdev = bus->self; >>+ slot->bus = bus; >>+ slot->id = id; >>+ slot->power_state_check = false; >>+ slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; >>+ slot->php_slot.ops = &php_slot_ops; >>+ slot->php_slot.info = &slot->php_slot_info; >>+ slot->php_slot.release = pnv_php_release; >>+ slot->php_slot.private = slot; >>+ >>+ INIT_WORK(&slot->work, pnv_php_work); >>+ init_waitqueue_head(&slot->queue); >>+ INIT_LIST_HEAD(&slot->children); >>+ INIT_LIST_HEAD(&slot->link); >>+ >>+ return slot; >>+} >>+ >>+static int pnv_php_register_slot(struct pnv_php_slot *slot) >>+{ >>+ struct pnv_php_slot *parent; >>+ struct device_node *dn = slot->dn; >>+ unsigned long flags; >>+ int ret; >>+ >>+ /* Check if the slot exists or not */ > >s/exists/is registered/ > > >>+ parent = pnv_php_find_slot(slot->dn); >>+ if (parent) { >>+ pnv_php_put_slot(parent); >>+ return -EEXIST; >>+ } >>+ >>+ /* Register PCI slot */ >>+ ret = pci_hp_register(&slot->php_slot, slot->bus, >>+ slot->slot_no, slot->name); >>+ if (ret) { >>+ dev_warn(&slot->pdev->dev, "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; >>+ } > >This is missing here: > >of_node_put(dn); > > >>+ } >>+ >>+ spin_lock_irqsave(&pnv_php_lock, flags); >>+ slot->parent = parent; >>+ if (parent) >>+ list_add_tail(&slot->link, &parent->children); >>+ else >>+ list_add_tail(&slot->link, &pnv_php_slot_list); >>+ spin_unlock_irqrestore(&pnv_php_lock, flags); >>+ >>+ slot->state = PNV_PHP_STATE_REGISTER; >>+ return 0; >>+} >>+ >>+static int pnv_php_register_one(struct device_node *dn) >>+{ >>+ struct pnv_php_slot *slot; >>+ const __be32 *prop32; >>+ int ret; >>+ >>+ /* Check if it's hotpluggable slot */ >>+ prop32 = of_get_property(dn, "ibm,slot-pluggable", NULL); >>+ if (!prop32 || !of_read_number(prop32, 1)) >>+ return -ENXIO; >>+ >>+ prop32 = of_get_property(dn, "ibm,reset-by-firmware", NULL); >>+ if (!prop32 || !of_read_number(prop32, 1)) >>+ return -ENXIO; >>+ >>+ slot = pnv_php_alloc_slot(dn); >>+ if (!slot) >>+ return -ENODEV; >>+ >>+ ret = pnv_php_register_slot(slot); >>+ if (ret) >>+ goto free_slot; >>+ >>+ ret = pnv_php_enable(slot, false); >>+ if (ret) >>+ goto unregister_slot; >>+ >>+ return 0; >>+ >>+unregister_slot: >>+ pnv_php_unregister_one(slot->dn); >>+free_slot: >>+ pnv_php_put_slot(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 *slot; >>+ >>+ slot = pnv_php_find_slot(dn); >>+ if (!slot) >>+ return; >>+ >>+ pnv_php_put_slot(slot); >>+ pci_hp_deregister(&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 struct notifier_block php_msg_nb = { >>+ .notifier_call = pnv_php_handle_msg, >>+ .next = NULL, >>+ .priority = 0, >>+}; >>+ >>+static int __init pnv_php_init(void) >>+{ >>+ struct device_node *dn; >>+ int ret; >>+ >>+ pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); >>+ >>+ /* Register hotplug message handler */ >>+ ret = pnv_pci_hotplug_notifier_register(&php_msg_nb); >>+ if (ret) { >>+ pr_warn("%s: Error %d registering hotplug notifier\n", >>+ __func__, ret); >>+ return ret; >>+ } >>+ >>+ /* Scan PHB nodes and their children */ >>+ for_each_compatible_node(dn, NULL, "ibm,ioda-phb") >>+ pnv_php_register(dn); >>+ 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,ioda-phb") >>+ pnv_php_unregister(dn); >>+ for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") >>+ pnv_php_unregister(dn); >>+ >>+ pnv_pci_hotplug_notifier_unregister(&php_msg_nb); >>+} >>+ >>+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); >> > > >-- >Alexey > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/MAINTAINERS b/MAINTAINERS index 9f6685f..10088f1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -7931,6 +7931,12 @@ L: linux-pci@vger.kernel.org S: Supported F: Documentation/PCI/pci-error-recovery.txt +PCI HOTPLUG DRIVER FOR POWERNV PLATFORM +M: Gavin Shan <gwshan@linux.vnet.ibm.com> +L: linux-pci@vger.kernel.org +S: Supported +F: drivers/pci/hotplug/pnv_php.c + PCI SUBSYSTEM M: Bjorn Helgaas <bhelgaas@google.com> L: linux-pci@vger.kernel.org diff --git a/drivers/pci/hotplug/Kconfig b/drivers/pci/hotplug/Kconfig index df8caec..167c8ce 100644 --- a/drivers/pci/hotplug/Kconfig +++ b/drivers/pci/hotplug/Kconfig @@ -113,6 +113,18 @@ config HOTPLUG_PCI_SHPC When in doubt, say N. +config HOTPLUG_PCI_POWERNV + tristate "PowerPC PowerNV PCI Hotplug driver" + depends on PPC_POWERNV && EEH + help + Say Y here if you run PowerPC PowerNV platform that supports + PCI Hotplug + + To compile this driver as a module, choose M here: the + module will be called pnv-php. + + When in doubt, say N. + config HOTPLUG_PCI_RPA tristate "RPA PCI Hotplug driver" depends on PPC_PSERIES && EEH diff --git a/drivers/pci/hotplug/Makefile b/drivers/pci/hotplug/Makefile index b616e75..e33cdda 100644 --- a/drivers/pci/hotplug/Makefile +++ b/drivers/pci/hotplug/Makefile @@ -14,6 +14,7 @@ obj-$(CONFIG_HOTPLUG_PCI_PCIE) += pciehp.o obj-$(CONFIG_HOTPLUG_PCI_CPCI_ZT5550) += cpcihp_zt5550.o obj-$(CONFIG_HOTPLUG_PCI_CPCI_GENERIC) += cpcihp_generic.o obj-$(CONFIG_HOTPLUG_PCI_SHPC) += shpchp.o +obj-$(CONFIG_HOTPLUG_PCI_POWERNV) += pnv-php.o obj-$(CONFIG_HOTPLUG_PCI_RPA) += rpaphp.o obj-$(CONFIG_HOTPLUG_PCI_RPA_DLPAR) += rpadlpar_io.o obj-$(CONFIG_HOTPLUG_PCI_SGI) += sgi_hotplug.o @@ -50,6 +51,8 @@ ibmphp-objs := ibmphp_core.o \ acpiphp-objs := acpiphp_core.o \ acpiphp_glue.o +pnv-php-objs := pnv_php.o + rpaphp-objs := rpaphp_core.o \ rpaphp_pci.o \ rpaphp_slot.o diff --git a/drivers/pci/hotplug/pnv_php.c b/drivers/pci/hotplug/pnv_php.c new file mode 100644 index 0000000..415e9b9 --- /dev/null +++ b/drivers/pci/hotplug/pnv_php.c @@ -0,0 +1,866 @@ +/* + * PCI Hotplug Driver for PowerPC PowerNV platform. + * + * Copyright Gavin Shan, IBM Corporation 2015. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + */ + +#include <linux/pci.h> +#include <linux/pci_hotplug.h> +#include <linux/module.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_slot { + struct hotplug_slot php_slot; + struct hotplug_slot_info php_slot_info; + uint64_t id; + char *name; + int slot_no; + struct kref kref; + int state; +#define PNV_PHP_STATE_INIT 0 +#define PNV_PHP_STATE_REGISTER 1 +#define PNV_PHP_STATE_POPULATED 2 + struct device_node *dn; + struct pci_dev *pdev; + struct pci_bus *bus; + bool power_state_check; + int power_state_confirmed; +#define PNV_PHP_POWER_CONFIRMED_INVALID 0 +#define PNV_PHP_POWER_CONFIRMED_SUCCESS 1 +#define PNV_PHP_POWER_CONFIRMED_FAIL 2 + struct opal_msg *msg; + void *fdt; + void *dt; + struct of_changeset ocs; + struct work_struct work; + wait_queue_head_t queue; + struct pnv_php_slot *parent; + struct list_head children; + struct list_head link; +}; + +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 inline struct pnv_php_slot *pnv_php_get_slot(struct pnv_php_slot *slot) +{ + if (slot) { + kref_get(&slot->kref); + return slot; + } + + return NULL; +} + +static void pnv_php_free_slot(struct kref *kref) +{ + struct pnv_php_slot *slot = container_of(kref, + struct pnv_php_slot, + kref); + + WARN_ON(!list_empty(&slot->children)); + kfree(slot->name); + kfree(slot); +} + +static inline void pnv_php_put_slot(struct pnv_php_slot *slot) +{ + if (!slot) + return; + + kref_put(&slot->kref, pnv_php_free_slot); +} + +static struct pnv_php_slot *pnv_php_match(struct device_node *dn, + struct pnv_php_slot *slot) +{ + struct pnv_php_slot *target, *tmp; + + if (slot->dn == dn) + return pnv_php_get_slot(slot); + + list_for_each_entry(tmp, &slot->children, link) { + target = pnv_php_match(dn, tmp); + if (target) + return target; + } + + return NULL; +} + +static struct pnv_php_slot *pnv_php_find_slot(struct device_node *dn) +{ + struct pnv_php_slot *slot, *tmp; + unsigned long flags; + + spin_lock_irqsave(&pnv_php_lock, flags); + list_for_each_entry(tmp, &pnv_php_slot_list, link) { + slot = pnv_php_match(dn, tmp); + if (slot) { + spin_unlock_irqrestore(&pnv_php_lock, flags); + return slot; + } + } + spin_unlock_irqrestore(&pnv_php_lock, flags); + + return NULL; +} + +/* + * 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); + } +} + +/* + * Remove all child nodes of the indicated device nodes. The + * function should remove device nodes in depth-first manner. + */ +static int pnv_php_rmv_device_nodes(struct device_node *parent) +{ + struct device_node *dn, *child; + int ret = 0; + + for_each_child_of_node(parent, dn) { + ret = pnv_php_rmv_device_nodes(dn); + if (ret) + return ret; + + child = of_get_next_child(dn, NULL); + if (child) { + of_node_put(child); + of_node_put(dn); + pr_err("%s: Alive children of node <%s>\n", + __func__, of_node_full_name(dn)); + return -EBUSY; + } + + of_detach_node(dn); + of_node_put(dn); + } + + return 0; +} + +/* + * The function processes the message sent by firmware + * to remove all device tree nodes beneath the slot's + * nodes and the associated auxiliary data. + */ +static void pnv_php_handle_poweroff(struct pnv_php_slot *slot) +{ + int ret; + + pnv_php_rmv_pdns(slot->dn); + + /* + * If the device sub-tree was created from OF changeset, simply + * to revert that. Otherwise, the device nodes in the sub-tree + * need to be iterated and detached. + */ + if (slot->fdt) { + of_changeset_destroy(&slot->ocs); + kfree(slot->dt); + kfree(slot->fdt); + slot->dt = NULL; + slot->dn->child = NULL; + slot->fdt = NULL; + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; + goto confirm; + } + + ret = pnv_php_rmv_device_nodes(slot->dn); + if (!ret) { + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_SUCCESS; + } else { + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_FAIL; + dev_warn(&slot->pdev->dev, "Error %d freeing nodes\n", + ret); + } + +confirm: + wake_up_interruptible(&slot->queue); +} + +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) + return ret; + + ret = pnv_php_populate_changeset(ocs, child); + } + + 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 void pnv_php_handle_poweron(struct pnv_php_slot *slot) +{ + void *fdt, *dt; + uint64_t len; + int confirm = PNV_PHP_POWER_CONFIRMED_SUCCESS; + int ret; + + /* We don't know the FDT blob size. It tries with incremental + * sized memory chunk. + */ + for (len = 0x2000; len <= 0x10000; len += 0x2000) { + fdt = kzalloc(len, GFP_KERNEL); + if (!fdt) + break; + + ret = pnv_pci_get_device_tree(slot->dn->phandle, fdt, len); + if (!ret) + break; + + kfree(fdt); + } + + if (len > 0x10000) { + dev_warn(&slot->pdev->dev, "Cannot alloc FDT blob\n"); + goto out; + } + + /* Unflatten device tree blob */ + dt = of_fdt_unflatten_tree(fdt, slot->dn, NULL); + if (!dt) { + dev_warn(&slot->pdev->dev, "Cannot unflatten FDT\n"); + goto free_fdt; + } + + /* Initialize and apply the changeset */ + of_changeset_init(&slot->ocs); + ret = pnv_php_populate_changeset(&slot->ocs, slot->dn); + if (ret) { + dev_warn(&slot->pdev->dev, "Error %d populating changeset\n", + ret); + goto free_dt; + } + + slot->dn->child = NULL; + ret = of_changeset_apply(&slot->ocs); + if (ret) { + dev_warn(&slot->pdev->dev, "Error %d applying changeset\n", + ret); + goto destroy_changeset; + } + + /* Add device node firmware data */ + pnv_php_add_pdns(slot); + slot->fdt = fdt; + slot->dt = dt; + goto out; + +destroy_changeset: + of_changeset_destroy(&slot->ocs); +free_dt: + kfree(dt); + slot->dn->child = NULL; +free_fdt: + kfree(fdt); + confirm = PNV_PHP_POWER_CONFIRMED_FAIL; +out: + /* Confirm status change */ + slot->power_state_confirmed = confirm; + wake_up_interruptible(&slot->queue); +} + +static void pnv_php_work(struct work_struct *data) +{ + struct pnv_php_slot *slot = container_of(data, + struct pnv_php_slot, work); + uint64_t event = be64_to_cpu(slot->msg->params[0]); + + if (event == OPAL_PCI_SLOT_POWER_OFF) + pnv_php_handle_poweroff(slot); + else + pnv_php_handle_poweron(slot); + + pnv_php_put_slot(slot); +} + +static int pnv_php_handle_msg(struct notifier_block *nb, + unsigned long type, + void *message) +{ + phandle h; + struct device_node *dn; + struct pnv_php_slot *slot; + struct opal_msg *msg = message; + + if (type != OPAL_MSG_PCI_HOTPLUG) { + pr_warn("%s: Invalid message %ld received!\n", + __func__, type); + return NOTIFY_DONE; + } + + h = (phandle)be64_to_cpu(msg->params[1]); + dn = of_find_node_by_phandle(h); + if (!dn) { + pr_warn("%s: No device node for phandle 0x%x\n", + __func__, h); + return NOTIFY_DONE; + } + + slot = pnv_php_find_slot(dn); + of_node_put(dn); + if (!slot) { + pr_warn("%s: No slot found for node <%s>\n", + __func__, of_node_full_name(dn)); + of_node_put(dn); + return NOTIFY_DONE; + } + + slot->msg = msg; + schedule_work(&slot->work); + return NOTIFY_OK; +} + +static int pnv_php_set_power_state(struct hotplug_slot *php_slot, u8 state) +{ + struct pnv_php_slot *slot = php_slot->private; + int ret; + + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; + ret = pnv_pci_set_power_state(slot->id, state); + if (ret) { + dev_warn(&slot->pdev->dev, "Error %d powering %s slot\n", + ret, state ? "on" : "off"); + return ret; + } + + /* Continue to PCI probing after finalized device-tree. The + * device-tree might have been updated completely at this + * point. Thus we don't have to always waiting for that. + */ + if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) + return 0; + else if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_FAIL) + return -EBUSY; + + ret = wait_event_timeout(slot->queue, + slot->power_state_confirmed, 10 * HZ); + if (!ret) { + dev_warn(&slot->pdev->dev, "Error %d waiting for power-%s\n", + ret, state ? "on" : "off"); + return -EBUSY; + } + + if (slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS) + return 0; + + dev_warn(&slot->pdev->dev, "Error status %d for power-%s\n", + slot->power_state_confirmed, state ? "on" : "off"); + return -EBUSY; +} + +static int pnv_php_get_power_state(struct hotplug_slot *php_slot, u8 *state) +{ + struct pnv_php_slot *slot = php_slot->private; + uint8_t power_state; + 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(slot->id, &power_state); + if (ret) { + *state = OPAL_PCI_SLOT_POWER_ON; + dev_warn(&slot->pdev->dev, "Error %d getting power status\n", + ret); + } else { + *state = power_state; + php_slot->info->power_status = power_state; + } + + return 0; +} + +static int pnv_php_get_adapter_state(struct hotplug_slot *php_slot, u8 *state) +{ + struct pnv_php_slot *slot = php_slot->private; + uint8_t presence; + 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(slot->id, &presence); + if (ret >= 0) { + *state = presence; + php_slot->info->adapter_status = presence; + ret = 0; + } else { + *state = OPAL_PCI_SLOT_EMPTY; + dev_warn(&slot->pdev->dev, "Error %d getting presence\n", + ret); + } + + return ret; +} + +static int pnv_php_set_attention_state(struct hotplug_slot *php_slot, u8 state) +{ + /* FIXME: Make it real once firmware supports it */ + php_slot->info->attention_status = state; + + return 0; +} + +static int pnv_php_enable(struct pnv_php_slot *slot, bool rescan) +{ + struct hotplug_slot *php_slot = &slot->php_slot; + uint8_t presence, power_status; + int ret; + + /* Check if the slot has been configured */ + if (slot->state != PNV_PHP_STATE_REGISTER) + return 0; + + /* Retrieve slot presence status */ + ret = php_slot->ops->get_adapter_status(php_slot, &presence); + if (ret) + return ret; + + /* Proceed if there have nothing behind the slot */ + if (presence == OPAL_PCI_SLOT_EMPTY) + goto scan; + + /* + * If we don't detect something behind the slot, we need + * make sure the power suply to the slot is on. Otherwise, + * the slot downstream PCIe linkturn should be down. + * + * 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 (!slot->power_state_check) { + slot->power_state_check = true; + goto scan; + } + + /* Check the power status. Scan the slot if that's already on */ + ret = php_slot->ops->get_power_status(php_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_power_state(php_slot, OPAL_PCI_SLOT_POWER_ON); + if (ret) + return ret; + +scan: + if (presence == OPAL_PCI_SLOT_PRESENT) { + if (rescan) { + pci_lock_rescan_remove(); + pci_add_pci_devices(slot->bus); + pci_unlock_rescan_remove(); + } + + /* Rescan for child hotpluggable slots */ + slot->state = PNV_PHP_STATE_POPULATED; + if (rescan) + pnv_php_register(slot->dn); + } else { + slot->state = PNV_PHP_STATE_POPULATED; + } + + return 0; +} + +static int pnv_php_enable_slot(struct hotplug_slot *php_slot) +{ + struct pnv_php_slot *slot = container_of(php_slot, + struct pnv_php_slot, + php_slot); + + return pnv_php_enable(slot, true); +} + +static int pnv_php_disable_slot(struct hotplug_slot *php_slot) +{ + struct pnv_php_slot *slot = php_slot->private; + uint8_t power_state; + int ret; + + if (slot->state != PNV_PHP_STATE_POPULATED) + return 0; + + /* Remove all devices behind the slot */ + pci_lock_rescan_remove(); + pci_remove_pci_devices(slot->bus); + pci_unlock_rescan_remove(); + + /* Detach the child hotpluggable slots */ + pnv_php_unregister(slot->dn); + + /* + * Check the power status and turn it off if necessary. If we + * fail to get the power status, the power will be forced to + * be off. + */ + ret = php_slot->ops->get_power_status(php_slot, &power_state); + if (ret || power_state == OPAL_PCI_SLOT_POWER_ON) { + ret = pnv_php_set_power_state(php_slot, + OPAL_PCI_SLOT_POWER_OFF); + if (ret) + dev_warn(&slot->pdev->dev, "Error %d powering off\n", + ret); + } + + /* Update slot state */ + slot->state = PNV_PHP_STATE_REGISTER; + return 0; +} + +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 hotplug_slot *hp_slot) +{ + struct pnv_php_slot *slot = hp_slot->private; + unsigned long flags; + + /* Remove from global or child list */ + spin_lock_irqsave(&pnv_php_lock, flags); + list_del(&slot->link); + spin_unlock_irqrestore(&pnv_php_lock, flags); + + /* Detach from parent */ + pnv_php_put_slot(slot); + pnv_php_put_slot(slot->parent); +} + +static int pnv_php_get_slot_id(struct device_node *dn, uint64_t *id) +{ + struct device_node *parent = dn; + const __be64 *prop64; + const __be32 *prop32; + + /* + * The hotpluggable slot always has a compound Id, which + * consists of 16-bits PHB Id, 16 bits bus/slot/function + * number, and compound indicator + */ + *id = (0x1ul << 63); + + /* Bus/Slot/Function number */ + prop32 = of_get_property(dn, "reg", NULL); + if (!prop32) + return -ENXIO; + *id |= ((of_read_number(prop32, 1) & 0x00ffff00) << 8); + + /* PHB Id */ + while ((parent = of_get_parent(parent))) { + if (!PCI_DN(parent)) { + of_node_put(parent); + break; + } + + if (!of_device_is_compatible(parent, "ibm,ioda2-phb") && + !of_device_is_compatible(parent, "ibm,ioda-phb")) { + of_node_put(parent); + continue; + } + + prop64 = of_get_property(parent, "ibm,opal-phbid", NULL); + if (!prop64) { + of_node_put(parent); + return -ENXIO; + } + + *id |= be64_to_cpup(prop64); + of_node_put(parent); + return 0; + } + + return -ENODEV; +} + +static struct pnv_php_slot *pnv_php_alloc_slot(struct device_node *dn) +{ + struct pnv_php_slot *slot; + struct pci_bus *bus; + const char *label; + uint64_t id; + + label = of_get_property(dn, "ibm,slot-label", NULL); + if (!label) + return NULL; + + if (pnv_php_get_slot_id(dn, &id)) + return NULL; + + bus = pci_find_bus_by_node(dn); + if (!bus) + return NULL; + + slot = kzalloc(sizeof(*slot), GFP_KERNEL); + if (!slot) + return NULL; + + slot->name = kstrdup(label, GFP_KERNEL); + if (!slot->name) { + kfree(slot); + return NULL; + } + + if (dn->child && PCI_DN(dn->child)) + slot->slot_no = PCI_SLOT(PCI_DN(dn->child)->devfn); + else + slot->slot_no = -1; /* Placeholder slot */ + + kref_init(&slot->kref); + slot->state = PNV_PHP_STATE_INIT; + slot->dn = dn; + slot->pdev = bus->self; + slot->bus = bus; + slot->id = id; + slot->power_state_check = false; + slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID; + slot->php_slot.ops = &php_slot_ops; + slot->php_slot.info = &slot->php_slot_info; + slot->php_slot.release = pnv_php_release; + slot->php_slot.private = slot; + + INIT_WORK(&slot->work, pnv_php_work); + init_waitqueue_head(&slot->queue); + INIT_LIST_HEAD(&slot->children); + INIT_LIST_HEAD(&slot->link); + + return slot; +} + +static int pnv_php_register_slot(struct pnv_php_slot *slot) +{ + struct pnv_php_slot *parent; + struct device_node *dn = slot->dn; + unsigned long flags; + int ret; + + /* Check if the slot exists or not */ + parent = pnv_php_find_slot(slot->dn); + if (parent) { + pnv_php_put_slot(parent); + return -EEXIST; + } + + /* Register PCI slot */ + ret = pci_hp_register(&slot->php_slot, slot->bus, + slot->slot_no, slot->name); + if (ret) { + dev_warn(&slot->pdev->dev, "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; + } + } + + spin_lock_irqsave(&pnv_php_lock, flags); + slot->parent = parent; + if (parent) + list_add_tail(&slot->link, &parent->children); + else + list_add_tail(&slot->link, &pnv_php_slot_list); + spin_unlock_irqrestore(&pnv_php_lock, flags); + + slot->state = PNV_PHP_STATE_REGISTER; + return 0; +} + +static int pnv_php_register_one(struct device_node *dn) +{ + struct pnv_php_slot *slot; + const __be32 *prop32; + int ret; + + /* Check if it's hotpluggable slot */ + prop32 = of_get_property(dn, "ibm,slot-pluggable", NULL); + if (!prop32 || !of_read_number(prop32, 1)) + return -ENXIO; + + prop32 = of_get_property(dn, "ibm,reset-by-firmware", NULL); + if (!prop32 || !of_read_number(prop32, 1)) + return -ENXIO; + + slot = pnv_php_alloc_slot(dn); + if (!slot) + return -ENODEV; + + ret = pnv_php_register_slot(slot); + if (ret) + goto free_slot; + + ret = pnv_php_enable(slot, false); + if (ret) + goto unregister_slot; + + return 0; + +unregister_slot: + pnv_php_unregister_one(slot->dn); +free_slot: + pnv_php_put_slot(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 *slot; + + slot = pnv_php_find_slot(dn); + if (!slot) + return; + + pnv_php_put_slot(slot); + pci_hp_deregister(&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 struct notifier_block php_msg_nb = { + .notifier_call = pnv_php_handle_msg, + .next = NULL, + .priority = 0, +}; + +static int __init pnv_php_init(void) +{ + struct device_node *dn; + int ret; + + pr_info(DRIVER_DESC " version: " DRIVER_VERSION "\n"); + + /* Register hotplug message handler */ + ret = pnv_pci_hotplug_notifier_register(&php_msg_nb); + if (ret) { + pr_warn("%s: Error %d registering hotplug notifier\n", + __func__, ret); + return ret; + } + + /* Scan PHB nodes and their children */ + for_each_compatible_node(dn, NULL, "ibm,ioda-phb") + pnv_php_register(dn); + 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,ioda-phb") + pnv_php_unregister(dn); + for_each_compatible_node(dn, NULL, "ibm,ioda2-phb") + pnv_php_unregister(dn); + + pnv_pci_hotplug_notifier_unregister(&php_msg_nb); +} + +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);