[PATCH v8 45/45] PCI/hotplug: PowerPC PowerNV PCI hotplug driver
Alistair Popple
alistair at popple.id.au
Wed Apr 20 11:55:56 AEST 2016
On Tue, 19 Apr 2016 20:36:48 Alexey Kardashevskiy wrote:
> On 02/17/2016 02:44 PM, 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.
> >
> > The PCI slots are organized in fashion of tree, which means one
> > PCI slot might have parent PCI slot and parent PCI slot possibly
> > contains multiple child PCI slots. At the plugging time, the parent
> > PCI slot is populated before its children. The child PCI slots are
> > removed before their parent PCI slot can be removed from the system.
> >
> > 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.
> >
> > Signed-off-by: Gavin Shan <gwshan at linux.vnet.ibm.com>
> > Acked-by: Bjorn Helgaas <bhelgaas at google.com>
> > ---
> > drivers/pci/hotplug/Kconfig | 12 +
> > drivers/pci/hotplug/Makefile | 3 +
> > drivers/pci/hotplug/pnv_php.c | 870 ++++++++++++++++++++++++++++++++++++++++++
> > 3 files changed, 885 insertions(+)
> > create mode 100644 drivers/pci/hotplug/pnv_php.c
> >
> > 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..364ec36
> > --- /dev/null
> > +++ b/drivers/pci/hotplug/pnv_php.c
> > @@ -0,0 +1,870 @@
> > +/*
> > + * 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/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_slot {
> > + struct hotplug_slot slot;
> > + struct hotplug_slot_info slot_info;
> > + uint64_t id;
> > + char *name;
> > + int slot_no;
> > + struct kref kref;
> > +#define PNV_PHP_STATE_INITIALIZED 0
> > +#define PNV_PHP_STATE_REGISTERED 1
> > +#define PNV_PHP_STATE_POPULATED 2
> > + int state;
> > + 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);
>
>
> The names confused me. I'd suggest pnv_php_scan(), pnv_php_unregister(),
> pnv_php_unregister_children() instead.
>
>
> Alistair, what do you reckon?
To be honest I'm not sure the new names are necessarily any less confusing. I
will admit to having to read that code twice though so perhaps a short comment
describing what each of those functions does would be the best method for
reducing confusion.
- Alistair
> > +
> > +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));
> > + kfree(php_slot->name);
> > + kfree(php_slot);
> > +}
> > +
> > +static inline void pnv_php_put_slot(struct pnv_php_slot *php_slot)
> > +{
> > + if (!php_slot)
>
>
> BUG_ON()?
>
> > + 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;
> > +}
> > +
> > +static 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;
> > +}
> > +
> > +/*
> > + * 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 *php_slot)
> > +{
> > + int ret;
> > +
> > + pnv_php_rmv_pdns(php_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 (php_slot->fdt) {
> > + of_changeset_destroy(&php_slot->ocs);
> > + kfree(php_slot->dt);
> > + kfree(php_slot->fdt);
> > + php_slot->dt = NULL;
> > + php_slot->dn->child = NULL;
> > + php_slot->fdt = NULL;
> > + php_slot->power_state_confirmed =
> > + PNV_PHP_POWER_CONFIRMED_SUCCESS;
> > + wake_up_interruptible(&php_slot->queue);
> > + return;
> > + }
> > +
> > + ret = pnv_php_rmv_device_nodes(php_slot->dn);
> > + if (!ret) {
> > + php_slot->power_state_confirmed =
> > + PNV_PHP_POWER_CONFIRMED_SUCCESS;
> > + } else {
> > + php_slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_FAIL;
> > + dev_warn(&php_slot->pdev->dev, "Error %d freeing nodes\n", ret);
> > + }
> > +
> > + wake_up_interruptible(&php_slot->queue);
>
>
> I liked one wake_up_interruptible() better...
>
>
>
> > +}
> > +
> > +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)
> > + break;
> > +
> > + ret = pnv_php_populate_changeset(ocs, child);
>
>
> I asked in v7 - may be to add here "if (ret) 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 void pnv_php_handle_poweron(struct pnv_php_slot *php_slot)
> > +{
> > + void *fdt, *fdt1, *dt;
> > + int confirm = PNV_PHP_POWER_CONFIRMED_SUCCESS;
> > + 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)
> > + goto error;
> > +
> > + ret = pnv_pci_get_device_tree(php_slot->dn->phandle, fdt1, 0x10000);
> > + if (ret)
> > + goto free_fdt1;
> > +
> > + fdt = kzalloc(fdt_totalsize(fdt1), GFP_KERNEL);
> > + if (!fdt)
> > + 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) {
> > + dev_warn(&php_slot->pdev->dev, "Cannot unflatten FDT\n");
> > + goto free_fdt;
> > + }
> > +
> > + /* Initialize and apply the changeset */
> > + of_changeset_init(&php_slot->ocs);
> > + ret = pnv_php_populate_changeset(&php_slot->ocs, php_slot->dn);
> > + if (ret) {
> > + dev_warn(&php_slot->pdev->dev, "Error %d populating changeset\n",
> > + ret);
> > + goto free_dt;
> > + }
> > +
> > + php_slot->dn->child = NULL;
> > + ret = of_changeset_apply(&php_slot->ocs);
> > + if (ret) {
> > + dev_warn(&php_slot->pdev->dev, "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;
> > + 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);
> > +error:
> > + confirm = PNV_PHP_POWER_CONFIRMED_FAIL;
> > +out:
> > + /* Confirm status change */
> > + php_slot->power_state_confirmed = confirm;
> > + wake_up_interruptible(&php_slot->queue);
> > +}
> > +
> > +static void pnv_php_work(struct work_struct *data)
> > +{
> > + struct pnv_php_slot *php_slot = container_of(data,
> > + struct pnv_php_slot,
> > + work);
> > + uint64_t event = be64_to_cpu(php_slot->msg->params[0]);
> > +
> > + if (event == OPAL_PCI_SLOT_POWER_OFF)
> > + pnv_php_handle_poweroff(php_slot);
> > + else
> > + pnv_php_handle_poweron(php_slot);
> > +
> > + pnv_php_put_slot(php_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 *php_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;
> > + }
> > +
> > + php_slot = pnv_php_find_slot(dn);
> > + if (!php_slot) {
> > + pr_warn("%s: No slot found for node <%s>\n",
> > + __func__, of_node_full_name(dn));
> > + of_node_put(dn);
> > + return NOTIFY_DONE;
> > + }
> > +
> > + of_node_put(dn);
> > + php_slot->msg = msg;
> > + schedule_work(&php_slot->work);
> > + return NOTIFY_OK;
> > +}
> > +
> > +static int pnv_php_set_power_state(struct hotplug_slot *slot, u8 state)
> > +{
> > + struct pnv_php_slot *php_slot = slot->private;
> > + int ret;
> > +
> > + php_slot->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID;
> > + ret = pnv_pci_set_power_state(php_slot->id, state);
> > + if (ret) {
> > + dev_warn(&php_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 wait forever.
> > + */
> > + if (php_slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS)
> > + return 0;
> > +
> > + if (php_slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_FAIL)
> > + return -EBUSY;
> > +
> > + /* Wait for firmware to add or remove device sub-tree. When it's done,
> > + * one signal is received from firmware.
> > + */
> > + ret = wait_event_timeout(php_slot->queue,
> > + php_slot->power_state_confirmed, 10 * HZ);
> > + if (!ret) {
> > + dev_warn(&php_slot->pdev->dev, "Error %d waiting for power-%s\n",
> > + ret, state ? "on" : "off");
> > + return -EBUSY;
> > + }
> > +
> > + if (php_slot->power_state_confirmed == PNV_PHP_POWER_CONFIRMED_SUCCESS)
> > + return 0;
> > +
> > + dev_warn(&php_slot->pdev->dev, "Error status %d for power-%s\n",
> > + php_slot->power_state_confirmed, state ? "on" : "off");
> > + return -EBUSY;
> > +}
> > +
> > +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;
>
>
> Uninitialized variable.
>
>
> > + 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) {
> > + *state = OPAL_PCI_SLOT_POWER_ON;
> > + dev_warn(&php_slot->pdev->dev, "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;
>
> Uninitialized variable.
>
>
> > + 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 {
> > + *state = OPAL_PCI_SLOT_EMPTY;
> > + dev_warn(&php_slot->pdev->dev, "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 */
>
> It still does not?
>
>
> > + 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, power_status;
>
>
> Uninitialized variables.
>
>
> > + 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 */
> > + if (presence == OPAL_PCI_SLOT_EMPTY)
> > + goto scan;
> > +
> > + /*
> > + * If the power suply to the slot is off, we can't detect
>
> s/suply/supply/
>
>
> > + * 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 that's already on */
>
>
> s/that's/it is/
>
>
> > + 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_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_add_pci_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;
> > + uint8_t power_state;
> > + int ret;
> > +
> > + if (php_slot->state != PNV_PHP_STATE_POPULATED)
> > + return 0;
> > +
> > + /* Remove all devices behind the slot */
> > + pci_lock_rescan_remove();
> > + pci_remove_pci_devices(php_slot->bus);
> > + pci_unlock_rescan_remove();
> > +
> > + /* Detach the child hotpluggable slots */
> > + pnv_php_unregister(php_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 = pnv_php_get_power_state(slot, &power_state);
> > + if (ret || power_state == OPAL_PCI_SLOT_POWER_ON) {
> > + ret = pnv_php_set_power_state(slot, OPAL_PCI_SLOT_POWER_OFF);
> > + if (ret)
> > + dev_warn(&php_slot->pdev->dev, "Error %d powering off\n",
>
>
> Long line, checkpatch.pl should have warned :)
>
>
> > + ret);
> > + }
> > +
> > + /* Update slot state */
> > + php_slot->state = PNV_PHP_STATE_REGISTERED;
> > + 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 *slot)
> > +{
> > + struct pnv_php_slot *php_slot = slot->private;
> > + 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 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);
>
>
> Is this bit from the same space as 1<<60 as in pnv_eeh_bridge_reset()? If
> so, it would be great to have all these id bits defined in one place.
>
>
> > +
> > + /* 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 *php_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;
> > +
> > + 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->power_state_confirmed = PNV_PHP_POWER_CONFIRMED_INVALID;
> > + php_slot->slot.ops = &php_slot_ops;
> > + php_slot->slot.info = &php_slot->slot_info;
> > + php_slot->slot.release = pnv_php_release;
> > + php_slot->slot.private = php_slot;
> > +
> > + INIT_WORK(&php_slot->work, pnv_php_work);
> > + init_waitqueue_head(&php_slot->queue);
> > + 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) {
> > + dev_warn(&php_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;
> > + }
> > +
> > + 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_register_one(struct device_node *dn)
> > +{
> > + struct pnv_php_slot *php_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;
> > +
> > + 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;
> > +
> > + 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;
> > +
> > + pnv_php_put_slot(php_slot);
> > + pci_hp_deregister(&php_slot->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);
> >
>
>
>
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