/*
   * Copyright (C) 2007-2008 Advanced Micro Devices, Inc.
   * Author: Joerg Roedel <joerg.roedel@amd.com>
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   */
  
  #ifndef __LINUX_IOMMU_H
  #define __LINUX_IOMMU_H
  
  #include <linux/errno.h>
  #include <linux/err.h>
  #include <linux/types.h>
  #include <trace/events/iommu.h>
  
  #define IOMMU_READ	(1 << 0)
  #define IOMMU_WRITE	(1 << 1)
  #define IOMMU_CACHE	(1 << 2) /* DMA cache coherency */
  #define IOMMU_EXEC	(1 << 3)
  
  struct iommu_ops;
  struct iommu_group;
  struct bus_type;
  struct device;
  struct iommu_domain;
  struct notifier_block;
  
  /* iommu fault flags */
  #define IOMMU_FAULT_READ	0x0
  #define IOMMU_FAULT_WRITE	0x1
  
  typedef int (*iommu_fault_handler_t)(struct iommu_domain *,
  			struct device *, unsigned long, int, void *);
  
  struct iommu_domain_geometry {
  	dma_addr_t aperture_start; /* First address that can be mapped    */
  	dma_addr_t aperture_end;   /* Last address that can be mapped     */
  	bool force_aperture;       /* DMA only allowed in mappable range? */
  };
  
  struct iommu_domain {
  	struct iommu_ops *ops;
  	void *priv;
  	iommu_fault_handler_t handler;
  	void *handler_token;
  	struct iommu_domain_geometry geometry;
  };
  
  #define IOMMU_CAP_CACHE_COHERENCY	0x1
  #define IOMMU_CAP_INTR_REMAP		0x2	/* isolates device intrs */
  
  /*
   * Following constraints are specifc to FSL_PAMUV1:
   *  -aperture must be power of 2, and naturally aligned
   *  -number of windows must be power of 2, and address space size
   *   of each window is determined by aperture size / # of windows
   *  -the actual size of the mapped region of a window must be power
   *   of 2 starting with 4KB and physical address must be naturally
   *   aligned.
   * DOMAIN_ATTR_FSL_PAMUV1 corresponds to the above mentioned contraints.
   * The caller can invoke iommu_domain_get_attr to check if the underlying
   * iommu implementation supports these constraints.
   */
  
  enum iommu_attr {
  	DOMAIN_ATTR_GEOMETRY,
  	DOMAIN_ATTR_PAGING,
  	DOMAIN_ATTR_WINDOWS,
  	DOMAIN_ATTR_FSL_PAMU_STASH,
  	DOMAIN_ATTR_FSL_PAMU_ENABLE,
  	DOMAIN_ATTR_FSL_PAMUV1,
  	DOMAIN_ATTR_MAX,
  };
  
  #ifdef CONFIG_IOMMU_API
  
  /**
   * struct iommu_ops - iommu ops and capabilities
   * @domain_init: init iommu domain
   * @domain_destroy: destroy iommu domain
   * @attach_dev: attach device to an iommu domain
   * @detach_dev: detach device from an iommu domain
   * @map: map a physically contiguous memory region to an iommu domain
   * @unmap: unmap a physically contiguous memory region from an iommu domain
   * @iova_to_phys: translate iova to physical address
   * @domain_has_cap: domain capabilities query
   * @add_device: add device to iommu grouping
   * @remove_device: remove device from iommu grouping
   * @domain_get_attr: Query domain attributes
   * @domain_set_attr: Change domain attributes
   * @pgsize_bitmap: bitmap of supported page sizes
   */
  struct iommu_ops {
  	int (*domain_init)(struct iommu_domain *domain);
  	void (*domain_destroy)(struct iommu_domain *domain);
  	int (*attach_dev)(struct iommu_domain *domain, struct device *dev);
  	void (*detach_dev)(struct iommu_domain *domain, struct device *dev);
  	int (*map)(struct iommu_domain *domain, unsigned long iova,
  		   phys_addr_t paddr, size_t size, int prot);
  	size_t (*unmap)(struct iommu_domain *domain, unsigned long iova,
  		     size_t size);
  	phys_addr_t (*iova_to_phys)(struct iommu_domain *domain, dma_addr_t iova);
  	int (*domain_has_cap)(struct iommu_domain *domain,
  			      unsigned long cap);
  	int (*add_device)(struct device *dev);
  	void (*remove_device)(struct device *dev);
  	int (*device_group)(struct device *dev, unsigned int *groupid);
  	int (*domain_get_attr)(struct iommu_domain *domain,
  			       enum iommu_attr attr, void *data);
  	int (*domain_set_attr)(struct iommu_domain *domain,
  			       enum iommu_attr attr, void *data);
  
  	/* Window handling functions */
  	int (*domain_window_enable)(struct iommu_domain *domain, u32 wnd_nr,
  				    phys_addr_t paddr, u64 size, int prot);
  	void (*domain_window_disable)(struct iommu_domain *domain, u32 wnd_nr);
  	/* Set the numer of window per domain */
  	int (*domain_set_windows)(struct iommu_domain *domain, u32 w_count);
  	/* Get the numer of window per domain */
  	u32 (*domain_get_windows)(struct iommu_domain *domain);
  
  	unsigned long pgsize_bitmap;
  };
  
  #define IOMMU_GROUP_NOTIFY_ADD_DEVICE		1 /* Device added */
  #define IOMMU_GROUP_NOTIFY_DEL_DEVICE		2 /* Pre Device removed */
  #define IOMMU_GROUP_NOTIFY_BIND_DRIVER		3 /* Pre Driver bind */
  #define IOMMU_GROUP_NOTIFY_BOUND_DRIVER		4 /* Post Driver bind */
  #define IOMMU_GROUP_NOTIFY_UNBIND_DRIVER	5 /* Pre Driver unbind */
  #define IOMMU_GROUP_NOTIFY_UNBOUND_DRIVER	6 /* Post Driver unbind */
  
  extern int bus_set_iommu(struct bus_type *bus, struct iommu_ops *ops);
  extern bool iommu_present(struct bus_type *bus);
  extern struct iommu_domain *iommu_domain_alloc(struct bus_type *bus);
  extern struct iommu_group *iommu_group_get_by_id(int id);
  extern void iommu_domain_free(struct iommu_domain *domain);
  extern int iommu_attach_device(struct iommu_domain *domain,
  			       struct device *dev);
  extern void iommu_detach_device(struct iommu_domain *domain,
  				struct device *dev);
  extern int iommu_map(struct iommu_domain *domain, unsigned long iova,
  		     phys_addr_t paddr, size_t size, int prot);
  extern size_t iommu_unmap(struct iommu_domain *domain, unsigned long iova,
  		       size_t size);
  extern phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova);
  extern int iommu_domain_has_cap(struct iommu_domain *domain,
  				unsigned long cap);
  extern void iommu_set_fault_handler(struct iommu_domain *domain,
  			iommu_fault_handler_t handler, void *token);
  
  extern int iommu_attach_group(struct iommu_domain *domain,
  			      struct iommu_group *group);
  extern void iommu_detach_group(struct iommu_domain *domain,
  			       struct iommu_group *group);
  extern struct iommu_group *iommu_group_alloc(void);
  extern void *iommu_group_get_iommudata(struct iommu_group *group);
  extern void iommu_group_set_iommudata(struct iommu_group *group,
  				      void *iommu_data,
  				      void (*release)(void *iommu_data));
  extern int iommu_group_set_name(struct iommu_group *group, const char *name);
  extern int iommu_group_add_device(struct iommu_group *group,
  				  struct device *dev);
  extern void iommu_group_remove_device(struct device *dev);
  extern int iommu_group_for_each_dev(struct iommu_group *group, void *data,
  				    int (*fn)(struct device *, void *));
  extern struct iommu_group *iommu_group_get(struct device *dev);
  extern void iommu_group_put(struct iommu_group *group);
  extern int iommu_group_register_notifier(struct iommu_group *group,
  					 struct notifier_block *nb);
  extern int iommu_group_unregister_notifier(struct iommu_group *group,
  					   struct notifier_block *nb);
  extern int iommu_group_id(struct iommu_group *group);
  
  extern int iommu_domain_get_attr(struct iommu_domain *domain, enum iommu_attr,
  				 void *data);
  extern int iommu_domain_set_attr(struct iommu_domain *domain, enum iommu_attr,
  				 void *data);
  
  /* Window handling function prototypes */
  extern int iommu_domain_window_enable(struct iommu_domain *domain, u32 wnd_nr,
  				      phys_addr_t offset, u64 size,
  				      int prot);
  extern void iommu_domain_window_disable(struct iommu_domain *domain, u32 wnd_nr);
  /**
   * report_iommu_fault() - report about an IOMMU fault to the IOMMU framework
   * @domain: the iommu domain where the fault has happened
   * @dev: the device where the fault has happened
   * @iova: the faulting address
   * @flags: mmu fault flags (e.g. IOMMU_FAULT_READ/IOMMU_FAULT_WRITE/...)
   *
   * This function should be called by the low-level IOMMU implementations
   * whenever IOMMU faults happen, to allow high-level users, that are
   * interested in such events, to know about them.
   *
   * This event may be useful for several possible use cases:
   * - mere logging of the event
   * - dynamic TLB/PTE loading
   * - if restarting of the faulting device is required
   *
   * Returns 0 on success and an appropriate error code otherwise (if dynamic
   * PTE/TLB loading will one day be supported, implementations will be able
   * to tell whether it succeeded or not according to this return value).
   *
   * Specifically, -ENOSYS is returned if a fault handler isn't installed
   * (though fault handlers can also return -ENOSYS, in case they want to
   * elicit the default behavior of the IOMMU drivers).
   */
  static inline int report_iommu_fault(struct iommu_domain *domain,
  		struct device *dev, unsigned long iova, int flags)
  {
  	int ret = -ENOSYS;
  
  	/*
  	 * if upper layers showed interest and installed a fault handler,
  	 * invoke it.
  	 */
  	if (domain->handler)
  		ret = domain->handler(domain, dev, iova, flags,
  						domain->handler_token);
  
  	trace_io_page_fault(dev, iova, flags);
  	return ret;
  }
  
  #else /* CONFIG_IOMMU_API */
  
  struct iommu_ops {};
  struct iommu_group {};
  
  static inline bool iommu_present(struct bus_type *bus)
  {
  	return false;
  }
  
  static inline struct iommu_domain *iommu_domain_alloc(struct bus_type *bus)
  {
  	return NULL;
  }
  
  static inline struct iommu_group *iommu_group_get_by_id(int id)
  {
  	return NULL;
  }
  
  static inline void iommu_domain_free(struct iommu_domain *domain)
  {
  }
  
  static inline int iommu_attach_device(struct iommu_domain *domain,
  				      struct device *dev)
  {
  	return -ENODEV;
  }
  
  static inline void iommu_detach_device(struct iommu_domain *domain,
  				       struct device *dev)
  {
  }
  
  static inline int iommu_map(struct iommu_domain *domain, unsigned long iova,
  			    phys_addr_t paddr, int gfp_order, int prot)
  {
  	return -ENODEV;
  }
  
  static inline int iommu_unmap(struct iommu_domain *domain, unsigned long iova,
  			      int gfp_order)
  {
  	return -ENODEV;
  }
  
  static inline int iommu_domain_window_enable(struct iommu_domain *domain,
  					     u32 wnd_nr, phys_addr_t paddr,
  					     u64 size, int prot)
  {
  	return -ENODEV;
  }
  
  static inline void iommu_domain_window_disable(struct iommu_domain *domain,
  					       u32 wnd_nr)
  {
  }
  
  static inline phys_addr_t iommu_iova_to_phys(struct iommu_domain *domain, dma_addr_t iova)
  {
  	return 0;
  }
  
  static inline int iommu_domain_has_cap(struct iommu_domain *domain,
  				       unsigned long cap)
  {
  	return 0;
  }
  
  static inline void iommu_set_fault_handler(struct iommu_domain *domain,
  				iommu_fault_handler_t handler, void *token)
  {
  }
  
  static inline int iommu_attach_group(struct iommu_domain *domain,
  				     struct iommu_group *group)
  {
  	return -ENODEV;
  }
  
  static inline void iommu_detach_group(struct iommu_domain *domain,
  				      struct iommu_group *group)
  {
  }
  
  static inline struct iommu_group *iommu_group_alloc(void)
  {
  	return ERR_PTR(-ENODEV);
  }
  
  static inline void *iommu_group_get_iommudata(struct iommu_group *group)
  {
  	return NULL;
  }
  
  static inline void iommu_group_set_iommudata(struct iommu_group *group,
  					     void *iommu_data,
  					     void (*release)(void *iommu_data))
  {
  }
  
  static inline int iommu_group_set_name(struct iommu_group *group,
  				       const char *name)
  {
  	return -ENODEV;
  }
  
  static inline int iommu_group_add_device(struct iommu_group *group,
  					 struct device *dev)
  {
  	return -ENODEV;
  }
  
  static inline void iommu_group_remove_device(struct device *dev)
  {
  }
  
  static inline int iommu_group_for_each_dev(struct iommu_group *group,
  					   void *data,
  					   int (*fn)(struct device *, void *))
  {
  	return -ENODEV;
  }
  
  static inline struct iommu_group *iommu_group_get(struct device *dev)
  {
  	return NULL;
  }
  
  static inline void iommu_group_put(struct iommu_group *group)
  {
  }
  
  static inline int iommu_group_register_notifier(struct iommu_group *group,
  						struct notifier_block *nb)
  {
  	return -ENODEV;
  }
  
  static inline int iommu_group_unregister_notifier(struct iommu_group *group,
  						  struct notifier_block *nb)
  {
  	return 0;
  }
  
  static inline int iommu_group_id(struct iommu_group *group)
  {
  	return -ENODEV;
  }
  
  static inline int iommu_domain_get_attr(struct iommu_domain *domain,
  					enum iommu_attr attr, void *data)
  {
  	return -EINVAL;
  }
  
  static inline int iommu_domain_set_attr(struct iommu_domain *domain,
  					enum iommu_attr attr, void *data)
  {
  	return -EINVAL;
  }
  
  #endif /* CONFIG_IOMMU_API */
  
  #endif /* __LINUX_IOMMU_H */