text: /*
   * Freescale Management Complex (MC) bus driver
   *
   * Copyright (C) 2014 Freescale Semiconductor, Inc.
   * Author: German Rivera <German.Rivera@freescale.com>
   *
   * This file is licensed under the terms of the GNU General Public
   * License version 2. This program is licensed "as is" without any
   * warranty of any kind, whether express or implied.
   */
  
  #include <linux/module.h>
  #include <linux/of_device.h>
  #include <linux/of_address.h>
  #include <linux/ioport.h>
  #include <linux/slab.h>
  #include <linux/limits.h>
  #include <linux/bitops.h>
  #include <linux/msi.h>
  #include <linux/dma-mapping.h>
  #include "../include/mc-bus.h"
  #include "../include/dpmng.h"
  #include "../include/mc-sys.h"
  
  #include "fsl-mc-private.h"
  #include "dprc-cmd.h"
  
  static struct kmem_cache *mc_dev_cache;
  
  /**
   * Default DMA mask for devices on a fsl-mc bus
   */
  #define FSL_MC_DEFAULT_DMA_MASK	(~0ULL)
  
  /**
   * struct fsl_mc - Private data of a "fsl,qoriq-mc" platform device
   * @root_mc_bus_dev: MC object device representing the root DPRC
   * @num_translation_ranges: number of entries in addr_translation_ranges
   * @translation_ranges: array of bus to system address translation ranges
   */
  struct fsl_mc {
  	struct fsl_mc_device *root_mc_bus_dev;
  	u8 num_translation_ranges;
  	struct fsl_mc_addr_translation_range *translation_ranges;
  };
  
  /**
   * struct fsl_mc_addr_translation_range - bus to system address translation
   * range
   * @mc_region_type: Type of MC region for the range being translated
   * @start_mc_offset: Start MC offset of the range being translated
   * @end_mc_offset: MC offset of the first byte after the range (last MC
   * offset of the range is end_mc_offset - 1)
   * @start_phys_addr: system physical address corresponding to start_mc_addr
   */
  struct fsl_mc_addr_translation_range {
  	enum dprc_region_type mc_region_type;
  	u64 start_mc_offset;
  	u64 end_mc_offset;
  	phys_addr_t start_phys_addr;
  };
  
  /**
   * fsl_mc_bus_match - device to driver matching callback
   * @dev: the MC object device structure to match against
   * @drv: the device driver to search for matching MC object device id
   * structures
   *
   * Returns 1 on success, 0 otherwise.
   */
  static int fsl_mc_bus_match(struct device *dev, struct device_driver *drv)
  {
  	const struct fsl_mc_device_id *id;
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  	struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(drv);
  	bool found = false;
  
  	if (WARN_ON(!fsl_mc_bus_exists()))
  		goto out;
  
  	if (!mc_drv->match_id_table)
  		goto out;
  
  	/*
  	 * If the object is not 'plugged' don't match.
  	 * Only exception is the root DPRC, which is a special case.
  	 */
  	if ((mc_dev->obj_desc.state & DPRC_OBJ_STATE_PLUGGED) == 0 &&
  	    !fsl_mc_is_root_dprc(&mc_dev->dev))
  		goto out;
  
  	/*
  	 * Traverse the match_id table of the given driver, trying to find
  	 * a matching for the given MC object device.
  	 */
  	for (id = mc_drv->match_id_table; id->vendor != 0x0; id++) {
  		if (id->vendor == mc_dev->obj_desc.vendor &&
  		    strcmp(id->obj_type, mc_dev->obj_desc.type) == 0) {
  			found = true;
  
  			break;
  		}
  	}
  
  out:
  	dev_dbg(dev, "%smatched\n", found ? "" : "not ");
  	return found;
  }
  
  /**
   * fsl_mc_bus_uevent - callback invoked when a device is added
   */
  static int fsl_mc_bus_uevent(struct device *dev, struct kobj_uevent_env *env)
  {
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  
  	if (add_uevent_var(env, "MODALIAS=fsl-mc:v%08Xd%s",
  			   mc_dev->obj_desc.vendor,
  			   mc_dev->obj_desc.type))
  		return -ENOMEM;
  
  	return 0;
  }
  
  static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
  			     char *buf)
  {
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  
  	return sprintf(buf, "fsl-mc:v%08Xd%s\n", mc_dev->obj_desc.vendor,
  		       mc_dev->obj_desc.type);
  }
  static DEVICE_ATTR_RO(modalias);
  
  static struct attribute *fsl_mc_dev_attrs[] = {
  	&dev_attr_modalias.attr,
  	NULL,
  };
  
  ATTRIBUTE_GROUPS(fsl_mc_dev);
  
  struct bus_type fsl_mc_bus_type = {
  	.name = "fsl-mc",
  	.match = fsl_mc_bus_match,
  	.uevent = fsl_mc_bus_uevent,
  	.dev_groups = fsl_mc_dev_groups,
  };
  EXPORT_SYMBOL_GPL(fsl_mc_bus_type);
  
  static atomic_t root_dprc_count = ATOMIC_INIT(0);
  
  static int fsl_mc_driver_probe(struct device *dev)
  {
  	struct fsl_mc_driver *mc_drv;
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  	int error;
  
  	if (WARN_ON(!dev->driver))
  		return -EINVAL;
  
  	mc_drv = to_fsl_mc_driver(dev->driver);
  	if (WARN_ON(!mc_drv->probe))
  		return -EINVAL;
  
  	error = mc_drv->probe(mc_dev);
  	if (error < 0) {
  		dev_err(dev, "MC object device probe callback failed: %d\n",
  			error);
  		return error;
  	}
  
  	return 0;
  }
  
  static int fsl_mc_driver_remove(struct device *dev)
  {
  	struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  	int error;
  
  	if (WARN_ON(!dev->driver))
  		return -EINVAL;
  
  	error = mc_drv->remove(mc_dev);
  	if (error < 0) {
  		dev_err(dev,
  			"MC object device remove callback failed: %d\n",
  			error);
  		return error;
  	}
  
  	return 0;
  }
  
  static void fsl_mc_driver_shutdown(struct device *dev)
  {
  	struct fsl_mc_driver *mc_drv = to_fsl_mc_driver(dev->driver);
  	struct fsl_mc_device *mc_dev = to_fsl_mc_device(dev);
  
  	mc_drv->shutdown(mc_dev);
  }
  
  /**
   * __fsl_mc_driver_register - registers a child device driver with the
   * MC bus
   *
   * This function is implicitly invoked from the registration function of
   * fsl_mc device drivers, which is generated by the
   * module_fsl_mc_driver() macro.
   */
  int __fsl_mc_driver_register(struct fsl_mc_driver *mc_driver,
  			     struct module *owner)
  {
  	int error;
  
  	mc_driver->driver.owner = owner;
  	mc_driver->driver.bus = &fsl_mc_bus_type;
  
  	if (mc_driver->probe)
  		mc_driver->driver.probe = fsl_mc_driver_probe;
  
  	if (mc_driver->remove)
  		mc_driver->driver.remove = fsl_mc_driver_remove;
  
  	if (mc_driver->shutdown)
  		mc_driver->driver.shutdown = fsl_mc_driver_shutdown;
  
  	error = driver_register(&mc_driver->driver);
  	if (error < 0) {
  		pr_err("driver_register() failed for %s: %d\n",
  		       mc_driver->driver.name, error);
  		return error;
  	}
  
  	pr_info("MC object device driver %s registered\n",
  		mc_driver->driver.name);
  	return 0;
  }
  EXPORT_SYMBOL_GPL(__fsl_mc_driver_register);
  
  /**
   * fsl_mc_driver_unregister - unregisters a device driver from the
   * MC bus
   */
  void fsl_mc_driver_unregister(struct fsl_mc_driver *mc_driver)
  {
  	driver_unregister(&mc_driver->driver);
  }
  EXPORT_SYMBOL_GPL(fsl_mc_driver_unregister);
  
  /**
   * fsl_mc_bus_exists - check if a root dprc exists
   */
  bool fsl_mc_bus_exists(void)
  {
  	return atomic_read(&root_dprc_count) > 0;
  }
  EXPORT_SYMBOL_GPL(fsl_mc_bus_exists);
  
  /**
   * fsl_mc_get_root_dprc - function to traverse to the root dprc
   */
  void fsl_mc_get_root_dprc(struct device *dev,
  			  struct device **root_dprc_dev)
  {
  	if (WARN_ON(!dev)) {
  		*root_dprc_dev = NULL;
  	} else if (WARN_ON(!dev_is_fsl_mc(dev))) {
  		*root_dprc_dev = NULL;
  	} else {
  		*root_dprc_dev = dev;
  		while (dev_is_fsl_mc((*root_dprc_dev)->parent))
  			*root_dprc_dev = (*root_dprc_dev)->parent;
  	}
  }
  EXPORT_SYMBOL_GPL(fsl_mc_get_root_dprc);
  
  static int get_dprc_attr(struct fsl_mc_io *mc_io,
  			 int container_id, struct dprc_attributes *attr)
  {
  	u16 dprc_handle;
  	int error;
  
  	error = dprc_open(mc_io, 0, container_id, &dprc_handle);
  	if (error < 0) {
  		dev_err(mc_io->dev, "dprc_open() failed: %d\n", error);
  		return error;
  	}
  
  	memset(attr, 0, sizeof(struct dprc_attributes));
  	error = dprc_get_attributes(mc_io, 0, dprc_handle, attr);
  	if (error < 0) {
  		dev_err(mc_io->dev, "dprc_get_attributes() failed: %d\n",
  			error);
  		goto common_cleanup;
  	}
  
  	error = 0;
  
  common_cleanup:
  	(void)dprc_close(mc_io, 0, dprc_handle);
  	return error;
  }
  
  static int get_dprc_icid(struct fsl_mc_io *mc_io,
  			 int container_id, u16 *icid)
  {
  	struct dprc_attributes attr;
  	int error;
  
  	error = get_dprc_attr(mc_io, container_id, &attr);
  	if (error == 0)
  		*icid = attr.icid;
  
  	return error;
  }
  
  static int get_dprc_version(struct fsl_mc_io *mc_io,
  			    int container_id, u16 *major, u16 *minor)
  {
  	struct dprc_attributes attr;
  	int error;
  
  	error = get_dprc_attr(mc_io, container_id, &attr);
  	if (error == 0) {
  		*major = attr.version.major;
  		*minor = attr.version.minor;
  	}
  
  	return error;
  }
  
  static int translate_mc_addr(struct fsl_mc_device *mc_dev,
  			     enum dprc_region_type mc_region_type,
  			     u64 mc_offset, phys_addr_t *phys_addr)
  {
  	int i;
  	struct device *root_dprc_dev;
  	struct fsl_mc *mc;
  
  	fsl_mc_get_root_dprc(&mc_dev->dev, &root_dprc_dev);
  	if (WARN_ON(!root_dprc_dev))
  		return -EINVAL;
  	mc = dev_get_drvdata(root_dprc_dev->parent);
  
  	if (mc->num_translation_ranges == 0) {
  		/*
  		 * Do identity mapping:
  		 */
  		*phys_addr = mc_offset;
  		return 0;
  	}
  
  	for (i = 0; i < mc->num_translation_ranges; i++) {
  		struct fsl_mc_addr_translation_range *range =
  			&mc->translation_ranges[i];
  
  		if (mc_region_type == range->mc_region_type &&
  		    mc_offset >= range->start_mc_offset &&
  		    mc_offset < range->end_mc_offset) {
  			*phys_addr = range->start_phys_addr +
  				     (mc_offset - range->start_mc_offset);
  			return 0;
  		}
  	}
  
  	return -EFAULT;
  }
  
  static int fsl_mc_device_get_mmio_regions(struct fsl_mc_device *mc_dev,
  					  struct fsl_mc_device *mc_bus_dev)
  {
  	int i;
  	int error;
  	struct resource *regions;
  	struct dprc_obj_desc *obj_desc = &mc_dev->obj_desc;
  	struct device *parent_dev = mc_dev->dev.parent;
  	enum dprc_region_type mc_region_type;
  
  	if (strcmp(obj_desc->type, "dprc") == 0 ||
  	    strcmp(obj_desc->type, "dpmcp") == 0) {
  		mc_region_type = DPRC_REGION_TYPE_MC_PORTAL;
  	} else if (strcmp(obj_desc->type, "dpio") == 0) {
  		mc_region_type = DPRC_REGION_TYPE_QBMAN_PORTAL;
  	} else {
  		/*
  		 * This function should not have been called for this MC object
  		 * type, as this object type is not supposed to have MMIO
  		 * regions
  		 */
  		WARN_ON(true);
  		return -EINVAL;
  	}
  
  	regions = kmalloc_array(obj_desc->region_count,
  				sizeof(regions[0]), GFP_KERNEL);
  	if (!regions)
  		return -ENOMEM;
  
  	for (i = 0; i < obj_desc->region_count; i++) {
  		struct dprc_region_desc region_desc;
  
  		error = dprc_get_obj_region(mc_bus_dev->mc_io,
  					    0,
  					    mc_bus_dev->mc_handle,
  					    obj_desc->type,
  					    obj_desc->id, i, &region_desc);
  		if (error < 0) {
  			dev_err(parent_dev,
  				"dprc_get_obj_region() failed: %d\n", error);
  			goto error_cleanup_regions;
  		}
  
  		WARN_ON(region_desc.size == 0);
  		error = translate_mc_addr(mc_dev, mc_region_type,
  					  region_desc.base_offset,
  					  &regions[i].start);
  		if (error < 0) {
  			dev_err(parent_dev,
  				"Invalid MC offset: %#x (for %s.%d\'s region %d)\n",
  				region_desc.base_offset,
  				obj_desc->type, obj_desc->id, i);
  			goto error_cleanup_regions;
  		}
  
  		regions[i].end = regions[i].start + region_desc.size - 1;
  		regions[i].name = "fsl-mc object MMIO region";
  		regions[i].flags = IORESOURCE_IO;
  		if (region_desc.flags & DPRC_REGION_CACHEABLE)
  			regions[i].flags |= IORESOURCE_CACHEABLE;
  	}
  
  	mc_dev->regions = regions;
  	return 0;
  
  error_cleanup_regions:
  	kfree(regions);
  	return error;
  }
  
  /**
   * fsl_mc_is_root_dprc - function to check if a given device is a root dprc
   */
  bool fsl_mc_is_root_dprc(struct device *dev)
  {
  	struct device *root_dprc_dev;
  
  	fsl_mc_get_root_dprc(dev, &root_dprc_dev);
  	if (!root_dprc_dev)
  		return false;
  	return dev == root_dprc_dev;
  }
  
  /**
   * Add a newly discovered MC object device to be visible in Linux
   */
  int fsl_mc_device_add(struct dprc_obj_desc *obj_desc,
  		      struct fsl_mc_io *mc_io,
  		      struct device *parent_dev,
  		      struct fsl_mc_device **new_mc_dev)
  {
  	int error;
  	struct fsl_mc_device *mc_dev = NULL;
  	struct fsl_mc_bus *mc_bus = NULL;
  	struct fsl_mc_device *parent_mc_dev;
  
  	if (dev_is_fsl_mc(parent_dev))
  		parent_mc_dev = to_fsl_mc_device(parent_dev);
  	else
  		parent_mc_dev = NULL;
  
  	if (strcmp(obj_desc->type, "dprc") == 0) {
  		/*
  		 * Allocate an MC bus device object:
  		 */
  		mc_bus = devm_kzalloc(parent_dev, sizeof(*mc_bus), GFP_KERNEL);
  		if (!mc_bus)
  			return -ENOMEM;
  
  		mc_dev = &mc_bus->mc_dev;
  	} else {
  		/*
  		 * Allocate a regular fsl_mc_device object:
  		 */
  		mc_dev = kmem_cache_zalloc(mc_dev_cache, GFP_KERNEL);
  		if (!mc_dev)
  			return -ENOMEM;
  	}
  
  	mc_dev->obj_desc = *obj_desc;
  	mc_dev->mc_io = mc_io;
  	device_initialize(&mc_dev->dev);
  	mc_dev->dev.parent = parent_dev;
  	mc_dev->dev.bus = &fsl_mc_bus_type;
  	dev_set_name(&mc_dev->dev, "%s.%d", obj_desc->type, obj_desc->id);
  
  	if (strcmp(obj_desc->type, "dprc") == 0) {
  		struct fsl_mc_io *mc_io2;
  
  		mc_dev->flags |= FSL_MC_IS_DPRC;
  
  		/*
  		 * To get the DPRC's ICID, we need to open the DPRC
  		 * in get_dprc_icid(). For child DPRCs, we do so using the
  		 * parent DPRC's MC portal instead of the child DPRC's MC
  		 * portal, in case the child DPRC is already opened with
  		 * its own portal (e.g., the DPRC used by AIOP).
  		 *
  		 * NOTE: There cannot be more than one active open for a
  		 * given MC object, using the same MC portal.
  		 */
  		if (parent_mc_dev) {
  			/*
  			 * device being added is a child DPRC device
  			 */
  			mc_io2 = parent_mc_dev->mc_io;
  		} else {
  			/*
  			 * device being added is the root DPRC device
  			 */
  			if (WARN_ON(!mc_io)) {
  				error = -EINVAL;
  				goto error_cleanup_dev;
  			}
  
  			mc_io2 = mc_io;
  
  			atomic_inc(&root_dprc_count);
  		}
  
  		error = get_dprc_icid(mc_io2, obj_desc->id, &mc_dev->icid);
  		if (error < 0)
  			goto error_cleanup_dev;
  	} else {
  		/*
  		 * A non-DPRC MC object device has to be a child of another
  		 * MC object (specifically a DPRC object)
  		 */
  		mc_dev->icid = parent_mc_dev->icid;
  		mc_dev->dma_mask = FSL_MC_DEFAULT_DMA_MASK;
  		mc_dev->dev.dma_mask = &mc_dev->dma_mask;
  		dev_set_msi_domain(&mc_dev->dev,
  				   dev_get_msi_domain(&parent_mc_dev->dev));
  	}
  
  	/*
  	 * Get MMIO regions for the device from the MC:
  	 *
  	 * NOTE: the root DPRC is a special case as its MMIO region is
  	 * obtained from the device tree
  	 */
  	if (parent_mc_dev && obj_desc->region_count != 0) {
  		error = fsl_mc_device_get_mmio_regions(mc_dev,
  						       parent_mc_dev);
  		if (error < 0)
  			goto error_cleanup_dev;
  	}
  
  	/* Objects are coherent, unless 'no shareability' flag set. */
  	if (!(obj_desc->flags & DPRC_OBJ_FLAG_NO_MEM_SHAREABILITY))
  		arch_setup_dma_ops(&mc_dev->dev, 0, 0, NULL, true);
  
  	/*
  	 * The device-specific probe callback will get invoked by device_add()
  	 */
  	error = device_add(&mc_dev->dev);
  	if (error < 0) {
  		dev_err(parent_dev,
  			"device_add() failed for device %s: %d\n",
  			dev_name(&mc_dev->dev), error);
  		goto error_cleanup_dev;
  	}
  
  	(void)get_device(&mc_dev->dev);
  	dev_dbg(parent_dev, "Added MC object device %s\n",
  		dev_name(&mc_dev->dev));
  
  	*new_mc_dev = mc_dev;
  	return 0;
  
  error_cleanup_dev:
  	kfree(mc_dev->regions);
  	if (mc_bus)
  		devm_kfree(parent_dev, mc_bus);
  	else
  		kmem_cache_free(mc_dev_cache, mc_dev);
  
  	return error;
  }
  EXPORT_SYMBOL_GPL(fsl_mc_device_add);
  
  /**
   * fsl_mc_device_remove - Remove a MC object device from being visible to
   * Linux
   *
   * @mc_dev: Pointer to a MC object device object
   */
  void fsl_mc_device_remove(struct fsl_mc_device *mc_dev)
  {
  	struct fsl_mc_bus *mc_bus = NULL;
  
  	kfree(mc_dev->regions);
  
  	/*
  	 * The device-specific remove callback will get invoked by device_del()
  	 */
  	device_del(&mc_dev->dev);
  	put_device(&mc_dev->dev);
  
  	if (strcmp(mc_dev->obj_desc.type, "dprc") == 0) {
  		mc_bus = to_fsl_mc_bus(mc_dev);
  
  		if (fsl_mc_is_root_dprc(&mc_dev->dev)) {
  			if (atomic_read(&root_dprc_count) > 0)
  				atomic_dec(&root_dprc_count);
  			else
  				WARN_ON(1);
  		}
  	}
  
  	if (mc_bus)
  		devm_kfree(mc_dev->dev.parent, mc_bus);
  	else
  		kmem_cache_free(mc_dev_cache, mc_dev);
  }
  EXPORT_SYMBOL_GPL(fsl_mc_device_remove);
  
  static int parse_mc_ranges(struct device *dev,
  			   int *paddr_cells,
  			   int *mc_addr_cells,
  			   int *mc_size_cells,
  			   const __be32 **ranges_start,
  			   u8 *num_ranges)
  {
  	const __be32 *prop;
  	int range_tuple_cell_count;
  	int ranges_len;
  	int tuple_len;
  	struct device_node *mc_node = dev->of_node;
  
  	*ranges_start = of_get_property(mc_node, "ranges", &ranges_len);
  	if (!(*ranges_start) || !ranges_len) {
  		dev_warn(dev,
  			 "missing or empty ranges property for device tree node '%s'\n",
  			 mc_node->name);
  
  		*num_ranges = 0;
  		return 0;
  	}
  
  	*paddr_cells = of_n_addr_cells(mc_node);
  
  	prop = of_get_property(mc_node, "#address-cells", NULL);
  	if (prop)
  		*mc_addr_cells = be32_to_cpup(prop);
  	else
  		*mc_addr_cells = *paddr_cells;
  
  	prop = of_get_property(mc_node, "#size-cells", NULL);
  	if (prop)
  		*mc_size_cells = be32_to_cpup(prop);
  	else
  		*mc_size_cells = of_n_size_cells(mc_node);
  
  	range_tuple_cell_count = *paddr_cells + *mc_addr_cells +
  				 *mc_size_cells;
  
  	tuple_len = range_tuple_cell_count * sizeof(__be32);
  	if (ranges_len % tuple_len != 0) {
  		dev_err(dev, "malformed ranges property '%s'\n", mc_node->name);
  		return -EINVAL;
  	}
  
  	*num_ranges = ranges_len / tuple_len;
  	return 0;
  }
  
  static int get_mc_addr_translation_ranges(struct device *dev,
  					  struct fsl_mc_addr_translation_range
  						**ranges,
  					  u8 *num_ranges)
  {
  	int error;
  	int paddr_cells;
  	int mc_addr_cells;
  	int mc_size_cells;
  	int i;
  	const __be32 *ranges_start;
  	const __be32 *cell;
  
  	error = parse_mc_ranges(dev,
  				&paddr_cells,
  				&mc_addr_cells,
  				&mc_size_cells,
  				&ranges_start,
  				num_ranges);
  	if (error < 0)
  		return error;
  
  	if (!(*num_ranges)) {
  		/*
  		 * Missing or empty ranges property ("ranges;") for the
  		 * 'fsl,qoriq-mc' node. In this case, identity mapping
  		 * will be used.
  		 */
  		*ranges = NULL;
  		return 0;
  	}
  
  	*ranges = devm_kcalloc(dev, *num_ranges,
  			       sizeof(struct fsl_mc_addr_translation_range),
  			       GFP_KERNEL);
  	if (!(*ranges))
  		return -ENOMEM;
  
  	cell = ranges_start;
  	for (i = 0; i < *num_ranges; ++i) {
  		struct fsl_mc_addr_translation_range *range = &(*ranges)[i];
  
  		range->mc_region_type = of_read_number(cell, 1);
  		range->start_mc_offset = of_read_number(cell + 1,
  							mc_addr_cells - 1);
  		cell += mc_addr_cells;
  		range->start_phys_addr = of_read_number(cell, paddr_cells);
  		cell += paddr_cells;
  		range->end_mc_offset = range->start_mc_offset +
  				     of_read_number(cell, mc_size_cells);
  
  		cell += mc_size_cells;
  	}
  
  	return 0;
  }
  
  /**
   * fsl_mc_bus_probe - callback invoked when the root MC bus is being
   * added
   */
  static int fsl_mc_bus_probe(struct platform_device *pdev)
  {
  	struct dprc_obj_desc obj_desc;
  	int error;
  	struct fsl_mc *mc;
  	struct fsl_mc_device *mc_bus_dev = NULL;
  	struct fsl_mc_io *mc_io = NULL;
  	int container_id;
  	phys_addr_t mc_portal_phys_addr;
  	u32 mc_portal_size;
  	struct mc_version mc_version;
  	struct resource res;
  
  	dev_info(&pdev->dev, "Root MC bus device probed");
  
  	mc = devm_kzalloc(&pdev->dev, sizeof(*mc), GFP_KERNEL);
  	if (!mc)
  		return -ENOMEM;
  
  	platform_set_drvdata(pdev, mc);
  
  	/*
  	 * Get physical address of MC portal for the root DPRC:
  	 */
  	error = of_address_to_resource(pdev->dev.of_node, 0, &res);
  	if (error < 0) {
  		dev_err(&pdev->dev,
  			"of_address_to_resource() failed for %s\n",
  			pdev->dev.of_node->full_name);
  		return error;
  	}
  
  	mc_portal_phys_addr = res.start;
  	mc_portal_size = resource_size(&res);
  	error = fsl_create_mc_io(&pdev->dev, mc_portal_phys_addr,
  				 mc_portal_size, NULL,
  				 FSL_MC_IO_ATOMIC_CONTEXT_PORTAL, &mc_io);
  	if (error < 0)
  		return error;
  
  	error = mc_get_version(mc_io, 0, &mc_version);
  	if (error != 0) {
  		dev_err(&pdev->dev,
  			"mc_get_version() failed with error %d\n", error);
  		goto error_cleanup_mc_io;
  	}
  
  	dev_info(&pdev->dev,
  		 "Freescale Management Complex Firmware version: %u.%u.%u\n",
  		 mc_version.major, mc_version.minor, mc_version.revision);
  
  	error = get_mc_addr_translation_ranges(&pdev->dev,
  					       &mc->translation_ranges,
  					       &mc->num_translation_ranges);
  	if (error < 0)
  		goto error_cleanup_mc_io;
  
  	error = dpmng_get_container_id(mc_io, 0, &container_id);
  	if (error < 0) {
  		dev_err(&pdev->dev,
  			"dpmng_get_container_id() failed: %d\n", error);
  		goto error_cleanup_mc_io;
  	}
  
  	memset(&obj_desc, 0, sizeof(struct dprc_obj_desc));
  	error = get_dprc_version(mc_io, container_id,
  				 &obj_desc.ver_major, &obj_desc.ver_minor);
  	if (error < 0)
  		goto error_cleanup_mc_io;
  
  	obj_desc.vendor = FSL_MC_VENDOR_FREESCALE;
  	strcpy(obj_desc.type, "dprc");
  	obj_desc.id = container_id;
  	obj_desc.irq_count = 1;
  	obj_desc.region_count = 0;
  
  	error = fsl_mc_device_add(&obj_desc, mc_io, &pdev->dev, &mc_bus_dev);
  	if (error < 0)
  		goto error_cleanup_mc_io;
  
  	mc->root_mc_bus_dev = mc_bus_dev;
  	return 0;
  
  error_cleanup_mc_io:
  	fsl_destroy_mc_io(mc_io);
  	return error;
  }
  
  /**
   * fsl_mc_bus_remove - callback invoked when the root MC bus is being
   * removed
   */
  static int fsl_mc_bus_remove(struct platform_device *pdev)
  {
  	struct fsl_mc *mc = platform_get_drvdata(pdev);
  
  	if (WARN_ON(!fsl_mc_is_root_dprc(&mc->root_mc_bus_dev->dev)))
  		return -EINVAL;
  
  	fsl_mc_device_remove(mc->root_mc_bus_dev);
  
  	fsl_destroy_mc_io(mc->root_mc_bus_dev->mc_io);
  	mc->root_mc_bus_dev->mc_io = NULL;
  
  	dev_info(&pdev->dev, "Root MC bus device removed");
  	return 0;
  }
  
  static const struct of_device_id fsl_mc_bus_match_table[] = {
  	{.compatible = "fsl,qoriq-mc",},
  	{},
  };
  
  MODULE_DEVICE_TABLE(of, fsl_mc_bus_match_table);
  
  static struct platform_driver fsl_mc_bus_driver = {
  	.driver = {
  		   .name = "fsl_mc_bus",
  		   .pm = NULL,
  		   .of_match_table = fsl_mc_bus_match_table,
  		   },
  	.probe = fsl_mc_bus_probe,
  	.remove = fsl_mc_bus_remove,
  };
  
  static int __init fsl_mc_bus_driver_init(void)
  {
  	int error;
  
  	mc_dev_cache = kmem_cache_create("fsl_mc_device",
  					 sizeof(struct fsl_mc_device), 0, 0,
  					 NULL);
  	if (!mc_dev_cache) {
  		pr_err("Could not create fsl_mc_device cache\n");
  		return -ENOMEM;
  	}
  
  	error = bus_register(&fsl_mc_bus_type);
  	if (error < 0) {
  		pr_err("fsl-mc bus type registration failed: %d\n", error);
  		goto error_cleanup_cache;
  	}
  
  	pr_info("fsl-mc bus type registered\n");
  
  	error = platform_driver_register(&fsl_mc_bus_driver);
  	if (error < 0) {
  		pr_err("platform_driver_register() failed: %d\n", error);
  		goto error_cleanup_bus;
  	}
  
  	error = dprc_driver_init();
  	if (error < 0)
  		goto error_cleanup_driver;
  
  	error = fsl_mc_allocator_driver_init();
  	if (error < 0)
  		goto error_cleanup_dprc_driver;
  
  	error = its_fsl_mc_msi_init();
  	if (error < 0)
  		goto error_cleanup_mc_allocator;
  
  	return 0;
  
  error_cleanup_mc_allocator:
  	fsl_mc_allocator_driver_exit();
  
  error_cleanup_dprc_driver:
  	dprc_driver_exit();
  
  error_cleanup_driver:
  	platform_driver_unregister(&fsl_mc_bus_driver);
  
  error_cleanup_bus:
  	bus_unregister(&fsl_mc_bus_type);
  
  error_cleanup_cache:
  	kmem_cache_destroy(mc_dev_cache);
  	return error;
  }
  postcore_initcall(fsl_mc_bus_driver_init);
  