rpadlpar_core.c

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/*
 * Interface for Dynamic Logical Partitioning of I/O Slots on
 * RPA-compliant PPC64 platform.
 *
 * John Rose <[email protected]>
 * Linda Xie <[email protected]>
 *
 * October 2003
 *
 * Copyright (C) 2003 IBM.
 *
 *      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.
 */

#undef DEBUG

#include <linux/init.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/vmalloc.h>

#include <asm/pci-bridge.h>
#include <linux/mutex.h>
#include <asm/rtas.h>
#include <asm/vio.h>

#include "../pci.h"
#include "rpaphp.h"
#include "rpadlpar.h"

static DEFINE_MUTEX(rpadlpar_mutex);

#define DLPAR_MODULE_NAME "rpadlpar_io"

#define NODE_TYPE_VIO  1
#define NODE_TYPE_SLOT 2
#define NODE_TYPE_PHB  3

static struct device_node *find_vio_slot_node(char *drc_name)
{
    struct device_node *parent = of_find_node_by_name(NULL, "vdevice");
    struct device_node *dn = NULL;
    char *name;
    int rc;

    if (!parent)
        return NULL;

    while ((dn = of_get_next_child(parent, dn))) {
        rc = rpaphp_get_drc_props(dn, NULL, &name, NULL, NULL);
        if ((rc == 0) && (!strcmp(drc_name, name)))
            break;
    }

    return dn;
}

/* Find dlpar-capable pci node that contains the specified name and type */
static struct device_node *find_php_slot_pci_node(char *drc_name,
                          char *drc_type)
{
    struct device_node *np = NULL;
    char *name;
    char *type;
    int rc;

    while ((np = of_find_node_by_name(np, "pci"))) {
        rc = rpaphp_get_drc_props(np, NULL, &name, &type, NULL);
        if (rc == 0)
            if (!strcmp(drc_name, name) && !strcmp(drc_type, type))
                break;
    }

    return np;
}

static struct device_node *find_dlpar_node(char *drc_name, int *node_type)
{
    struct device_node *dn;

    dn = find_php_slot_pci_node(drc_name, "SLOT");
    if (dn) {
        *node_type = NODE_TYPE_SLOT;
        return dn;
    }

    dn = find_php_slot_pci_node(drc_name, "PHB");
    if (dn) {
        *node_type = NODE_TYPE_PHB;
        return dn;
    }

    dn = find_vio_slot_node(drc_name);
    if (dn) {
        *node_type = NODE_TYPE_VIO;
        return dn;
    }

    return NULL;
}

static struct slot *find_php_slot(struct device_node *dn)
{
    struct list_head *tmp, *n;
    struct slot *slot;

    list_for_each_safe(tmp, n, &rpaphp_slot_head) {
        slot = list_entry(tmp, struct slot, rpaphp_slot_list);
        if (slot->dn == dn)
            return slot;
    }

    return NULL;
}

static struct pci_dev *dlpar_find_new_dev(struct pci_bus *parent,
                    struct device_node *dev_dn)
{
    struct pci_dev *tmp = NULL;
    struct device_node *child_dn;

    list_for_each_entry(tmp, &parent->devices, bus_list) {
        child_dn = pci_device_to_OF_node(tmp);
        if (child_dn == dev_dn)
            return tmp;
    }
    return NULL;
}

static void dlpar_pci_add_bus(struct device_node *dn)
{
    struct pci_dn *pdn = PCI_DN(dn);
    struct pci_controller *phb = pdn->phb;
    struct pci_dev *dev = NULL;

    eeh_add_device_tree_early(dn);

    /* Add EADS device to PHB bus, adding new entry to bus->devices */
    dev = of_create_pci_dev(dn, phb->bus, pdn->devfn);
    if (!dev) {
        printk(KERN_ERR "%s: failed to create pci dev for %s\n",
                __func__, dn->full_name);
        return;
    }

    /* Scan below the new bridge */
    if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
        dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
        of_scan_pci_bridge(dev);

    /* Map IO space for child bus, which may or may not succeed */
    pcibios_map_io_space(dev->subordinate);

    /* Finish adding it : resource allocation, adding devices, etc...
     * Note that we need to perform the finish pass on the -parent-
     * bus of the EADS bridge so the bridge device itself gets
     * properly added
     */
    pcibios_finish_adding_to_bus(phb->bus);
}

static int dlpar_add_pci_slot(char *drc_name, struct device_node *dn)
{
    struct pci_dev *dev;
    struct pci_controller *phb;

    if (pcibios_find_pci_bus(dn))
        return -EINVAL;

    /* Add pci bus */
    dlpar_pci_add_bus(dn);

    /* Confirm new bridge dev was created */
    phb = PCI_DN(dn)->phb;
    dev = dlpar_find_new_dev(phb->bus, dn);

    if (!dev) {
        printk(KERN_ERR "%s: unable to add bus %s\n", __func__,
            drc_name);
        return -EIO;
    }

    if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
        printk(KERN_ERR "%s: unexpected header type %d, unable to add bus %s\n",
            __func__, dev->hdr_type, drc_name);
        return -EIO;
    }

    /* Add hotplug slot */
    if (rpaphp_add_slot(dn)) {
        printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
            __func__, drc_name);
        return -EIO;
    }
    return 0;
}

static int dlpar_remove_phb(char *drc_name, struct device_node *dn)
{
    struct slot *slot;
    struct pci_dn *pdn;
    int rc = 0;

    if (!pcibios_find_pci_bus(dn))
        return -EINVAL;

    /* If pci slot is hotplugable, use hotplug to remove it */
    slot = find_php_slot(dn);
    if (slot && rpaphp_deregister_slot(slot)) {
        printk(KERN_ERR "%s: unable to remove hotplug slot %s\n",
               __func__, drc_name);
        return -EIO;
    }

    pdn = dn->data;
    BUG_ON(!pdn || !pdn->phb);
    rc = remove_phb_dynamic(pdn->phb);
    if (rc < 0)
        return rc;

    pdn->phb = NULL;

    return 0;
}

static int dlpar_add_phb(char *drc_name, struct device_node *dn)
{
    struct pci_controller *phb;

    if (PCI_DN(dn) && PCI_DN(dn)->phb) {
        /* PHB already exists */
        return -EINVAL;
    }

    phb = init_phb_dynamic(dn);
    if (!phb)
        return -EIO;

    if (rpaphp_add_slot(dn)) {
        printk(KERN_ERR "%s: unable to add hotplug slot %s\n",
            __func__, drc_name);
        return -EIO;
    }
    return 0;
}

static int dlpar_add_vio_slot(char *drc_name, struct device_node *dn)
{
    if (vio_find_node(dn))
        return -EINVAL;

    if (!vio_register_device_node(dn)) {
        printk(KERN_ERR
            "%s: failed to register vio node %s\n",
            __func__, drc_name);
        return -EIO;
    }
    return 0;
}

int dlpar_add_slot(char *drc_name)
{
    struct device_node *dn = NULL;
    int node_type;
    int rc = -EIO;

    if (mutex_lock_interruptible(&rpadlpar_mutex))
        return -ERESTARTSYS;

    /* Find newly added node */
    dn = find_dlpar_node(drc_name, &node_type);
    if (!dn) {
        rc = -ENODEV;
        goto exit;
    }

    switch (node_type) {
        case NODE_TYPE_VIO:
            rc = dlpar_add_vio_slot(drc_name, dn);
            break;
        case NODE_TYPE_SLOT:
            rc = dlpar_add_pci_slot(drc_name, dn);
            break;
        case NODE_TYPE_PHB:
            rc = dlpar_add_phb(drc_name, dn);
            break;
    }

    printk(KERN_INFO "%s: slot %s added\n", DLPAR_MODULE_NAME, drc_name);
exit:
    mutex_unlock(&rpadlpar_mutex);
    return rc;
}

static int dlpar_remove_vio_slot(char *drc_name, struct device_node *dn)
{
    struct vio_dev *vio_dev;

    vio_dev = vio_find_node(dn);
    if (!vio_dev)
        return -EINVAL;

    vio_unregister_device(vio_dev);
    return 0;
}

int dlpar_remove_pci_slot(char *drc_name, struct device_node *dn)
{
    struct pci_bus *bus;
    struct slot *slot;

    bus = pcibios_find_pci_bus(dn);
    if (!bus)
        return -EINVAL;

    pr_debug("PCI: Removing PCI slot below EADS bridge %s\n",
         bus->self ? pci_name(bus->self) : "<!PHB!>");

    slot = find_php_slot(dn);
    if (slot) {
        pr_debug("PCI: Removing hotplug slot for %04x:%02x...\n",
             pci_domain_nr(bus), bus->number);

        if (rpaphp_deregister_slot(slot)) {
            printk(KERN_ERR
                "%s: unable to remove hotplug slot %s\n",
                __func__, drc_name);
            return -EIO;
        }
    }

    /* Remove all devices below slot */
    pcibios_remove_pci_devices(bus);

    /* Unmap PCI IO space */
    if (pcibios_unmap_io_space(bus)) {
        printk(KERN_ERR "%s: failed to unmap bus range\n",
            __func__);
        return -ERANGE;
    }

    /* Remove the EADS bridge device itself */
    BUG_ON(!bus->self);
    pr_debug("PCI: Now removing bridge device %s\n", pci_name(bus->self));
    eeh_remove_bus_device(bus->self, true);
    pci_stop_and_remove_bus_device(bus->self);

    return 0;
}

int dlpar_remove_slot(char *drc_name)
{
    struct device_node *dn;
    int node_type;
    int rc = 0;

    if (mutex_lock_interruptible(&rpadlpar_mutex))
        return -ERESTARTSYS;

    dn = find_dlpar_node(drc_name, &node_type);
    if (!dn) {
        rc = -ENODEV;
        goto exit;
    }

    switch (node_type) {
        case NODE_TYPE_VIO:
            rc = dlpar_remove_vio_slot(drc_name, dn);
            break;
        case NODE_TYPE_PHB:
            rc = dlpar_remove_phb(drc_name, dn);
            break;
        case NODE_TYPE_SLOT:
            rc = dlpar_remove_pci_slot(drc_name, dn);
            break;
    }
    vm_unmap_aliases();

    printk(KERN_INFO "%s: slot %s removed\n", DLPAR_MODULE_NAME, drc_name);
exit:
    mutex_unlock(&rpadlpar_mutex);
    return rc;
}

static inline int is_dlpar_capable(void)
{
    int rc = rtas_token("ibm,configure-connector");

    return (int) (rc != RTAS_UNKNOWN_SERVICE);
}

int __init rpadlpar_io_init(void)
{
    int rc = 0;

    if (!is_dlpar_capable()) {
        printk(KERN_WARNING "%s: partition not DLPAR capable\n",
            __func__);
        return -EPERM;
    }

    rc = dlpar_sysfs_init();
    return rc;
}

void rpadlpar_io_exit(void)
{
    dlpar_sysfs_exit();
    return;
}

module_init(rpadlpar_io_init);
module_exit(rpadlpar_io_exit);
MODULE_LICENSE("GPL");