/*
   * Interface for Dynamic Logical Partitioning of I/O Slots on
   * RPA-compliant PPC64 platform.
   *
   * John Rose <johnrose@austin.ibm.com>
   * Linda Xie <lxie@us.ibm.com>
   *
   * 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.
   */
  #include <linux/init.h>
  #include <linux/pci.h>

  #include <linux/string.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_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
  ",
  				__FUNCTION__, dn->full_name);

  		return;

  	}

  	if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
  	    dev->hdr_type == PCI_HEADER_TYPE_CARDBUS)
  		of_scan_pci_bridge(dn, dev);

  	pcibios_fixup_new_pci_devices(dev->subordinate,0);

  
  	/* Claim new bus resources */

  	pcibios_claim_one_bus(dev->bus);

  
  	/* ioremap() for child bus, which may or may not succeed */

  	remap_bus_range(dev->subordinate);

  	/* Add new devices to global lists.  Register in proc, sysfs. */

  	pci_bus_add_devices(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
  ", __FUNCTION__,
  			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
  ",
  			__FUNCTION__, 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
  ",
  			__FUNCTION__, drc_name);
  		return -EIO;
  	}

  	return 0;
  }
  
  static int dlpar_remove_root_bus(struct pci_controller *phb)
  {
  	struct pci_bus *phb_bus;
  	int rc;
  
  	phb_bus = phb->bus;
  	if (!(list_empty(&phb_bus->children) &&
  	      list_empty(&phb_bus->devices))) {
  		return -EBUSY;
  	}
  
  	rc = pcibios_remove_root_bus(phb);
  	if (rc)
  		return -EIO;
  
  	device_unregister(phb_bus->bridge);
  	pci_remove_bus(phb_bus);
  
  	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;

  	slot = find_slot(dn);
  	if (slot) {
  		/* Remove hotplug slot */

  		if (rpaphp_deregister_slot(slot)) {

  			printk(KERN_ERR
  				"%s: unable to remove hotplug slot %s
  ",
  				__FUNCTION__, drc_name);
  			return -EIO;
  		}

  	}

  	pdn = dn->data;
  	BUG_ON(!pdn || !pdn->phb);
  	rc = dlpar_remove_root_bus(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
  ",
  			__FUNCTION__, 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
  ",
  			__FUNCTION__, drc_name);
  		return -EIO;
  	}
  	return 0;
  }

  /**
   * dlpar_add_slot - DLPAR add an I/O Slot
   * @drc_name: drc-name of newly added slot
   *
   * Make the hotplug module and the kernel aware
   * of a newly added I/O Slot.
   * Return Codes -
   * 0			Success
   * -ENODEV		Not a valid drc_name
   * -EINVAL		Slot already added
   * -ERESTARTSYS		Signalled before obtaining lock
   * -EIO			Internal PCI Error
   */
  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
  ", DLPAR_MODULE_NAME, drc_name);

  exit:

  	mutex_unlock(&rpadlpar_mutex);

  	return rc;
  }
  
  /**
   * dlpar_remove_vio_slot - DLPAR remove a virtual I/O Slot
   * @drc_name: drc-name of newly added slot
   *
   * Remove the kernel and hotplug representations
   * of an I/O Slot.
   * Return Codes:
   * 0			Success

   * -EINVAL		Vio dev doesn't exist

   */

  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;
  }
  
  /**
   * dlpar_remove_slot - DLPAR remove a PCI I/O Slot
   * @drc_name: drc-name of newly added slot
   *
   * Remove the kernel and hotplug representations
   * of a PCI I/O Slot.
   * Return Codes:
   * 0			Success
   * -ENODEV		Not a valid drc_name
   * -EIO			Internal PCI Error
   */

  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;
  
  	slot = find_slot(dn);
  	if (slot) {
  		/* Remove hotplug slot */

  		if (rpaphp_deregister_slot(slot)) {

  			printk(KERN_ERR
  				"%s: unable to remove hotplug slot %s
  ",
  				__FUNCTION__, drc_name);
  			return -EIO;
  		}

  	} else {

  		struct pci_dev *dev, *tmp;
  		list_for_each_entry_safe(dev, tmp, &bus->devices, bus_list) {
  			eeh_remove_bus_device(dev);
  			pci_remove_bus_device(dev);
  		}

  	}

  	if (unmap_bus_range(bus)) {
  		printk(KERN_ERR "%s: failed to unmap bus range
  ",
  			__FUNCTION__);
  		return -ERANGE;

  	}

  
  	BUG_ON(!bus->self);
  	pci_remove_bus_device(bus->self);

  	return 0;
  }
  
  /**
   * dlpar_remove_slot - DLPAR remove an I/O Slot
   * @drc_name: drc-name of newly added slot
   *
   * Remove the kernel and hotplug representations
   * of an I/O Slot.
   * Return Codes:
   * 0			Success
   * -ENODEV		Not a valid drc_name
   * -EINVAL		Slot already removed
   * -ERESTARTSYS		Signalled before obtaining lock
   * -EIO			Internal Error
   */
  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;

  	}

  	printk(KERN_INFO "%s: slot %s removed
  ", 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
  ",
  			__FUNCTION__);
  		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");