/*
   * Copyright (C) 2007-2010 Advanced Micro Devices, Inc.
   * Author: Joerg Roedel <joerg.roedel@amd.com>
   *         Leo Duran <leo.duran@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 _ASM_X86_AMD_IOMMU_H
  #define _ASM_X86_AMD_IOMMU_H
  
  #include <linux/types.h>
  
  #ifdef CONFIG_AMD_IOMMU
  
  struct task_struct;
  struct pci_dev;
  
  extern int amd_iommu_detect(void);
  extern int amd_iommu_init_hardware(void);
  
  /**
   * amd_iommu_enable_device_erratum() - Enable erratum workaround for device
   *				       in the IOMMUv2 driver
   * @pdev: The PCI device the workaround is necessary for
   * @erratum: The erratum workaround to enable
   *
   * The function needs to be called before amd_iommu_init_device().
   * Possible values for the erratum number are for now:
   * - AMD_PRI_DEV_ERRATUM_ENABLE_RESET - Reset PRI capability when PRI
   *					is enabled
   * - AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE - Limit number of outstanding PRI
   *					 requests to one
   */
  #define AMD_PRI_DEV_ERRATUM_ENABLE_RESET		0
  #define AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE		1
  
  extern void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum);
  
  /**
   * amd_iommu_init_device() - Init device for use with IOMMUv2 driver
   * @pdev: The PCI device to initialize
   * @pasids: Number of PASIDs to support for this device
   *
   * This function does all setup for the device pdev so that it can be
   * used with IOMMUv2.
   * Returns 0 on success or negative value on error.
   */
  extern int amd_iommu_init_device(struct pci_dev *pdev, int pasids);
  
  /**
   * amd_iommu_free_device() - Free all IOMMUv2 related device resources
   *			     and disable IOMMUv2 usage for this device
   * @pdev: The PCI device to disable IOMMUv2 usage for'
   */
  extern void amd_iommu_free_device(struct pci_dev *pdev);
  
  /**
   * amd_iommu_bind_pasid() - Bind a given task to a PASID on a device
   * @pdev: The PCI device to bind the task to
   * @pasid: The PASID on the device the task should be bound to
   * @task: the task to bind
   *
   * The function returns 0 on success or a negative value on error.
   */
  extern int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
  				struct task_struct *task);
  
  /**
   * amd_iommu_unbind_pasid() - Unbind a PASID from its task on
   *			      a device
   * @pdev: The device of the PASID
   * @pasid: The PASID to unbind
   *
   * When this function returns the device is no longer using the PASID
   * and the PASID is no longer bound to its task.
   */
  extern void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid);
  
  /**
   * amd_iommu_set_invalid_ppr_cb() - Register a call-back for failed
   *				    PRI requests
   * @pdev: The PCI device the call-back should be registered for
   * @cb: The call-back function
   *
   * The IOMMUv2 driver invokes this call-back when it is unable to
   * successfully handle a PRI request. The device driver can then decide
   * which PRI response the device should see. Possible return values for
   * the call-back are:
   *
   * - AMD_IOMMU_INV_PRI_RSP_SUCCESS - Send SUCCESS back to the device
   * - AMD_IOMMU_INV_PRI_RSP_INVALID - Send INVALID back to the device
   * - AMD_IOMMU_INV_PRI_RSP_FAIL    - Send Failure back to the device,
   *				     the device is required to disable
   *				     PRI when it receives this response
   *
   * The function returns 0 on success or negative value on error.
   */
  #define AMD_IOMMU_INV_PRI_RSP_SUCCESS	0
  #define AMD_IOMMU_INV_PRI_RSP_INVALID	1
  #define AMD_IOMMU_INV_PRI_RSP_FAIL	2
  
  typedef int (*amd_iommu_invalid_ppr_cb)(struct pci_dev *pdev,
  					int pasid,
  					unsigned long address,
  					u16);
  
  extern int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
  					amd_iommu_invalid_ppr_cb cb);
  
  /**
   * amd_iommu_device_info() - Get information about IOMMUv2 support of a
   *			     PCI device
   * @pdev: PCI device to query information from
   * @info: A pointer to an amd_iommu_device_info structure which will contain
   *	  the information about the PCI device
   *
   * Returns 0 on success, negative value on error
   */
  
  #define AMD_IOMMU_DEVICE_FLAG_ATS_SUP     0x1    /* ATS feature supported */
  #define AMD_IOMMU_DEVICE_FLAG_PRI_SUP     0x2    /* PRI feature supported */
  #define AMD_IOMMU_DEVICE_FLAG_PASID_SUP   0x4    /* PASID context supported */
  #define AMD_IOMMU_DEVICE_FLAG_EXEC_SUP    0x8    /* Device may request execution
  						    on memory pages */
  #define AMD_IOMMU_DEVICE_FLAG_PRIV_SUP   0x10    /* Device may request
  						    super-user privileges */
  
  struct amd_iommu_device_info {
  	int max_pasids;
  	u32 flags;
  };
  
  extern int amd_iommu_device_info(struct pci_dev *pdev,
  				 struct amd_iommu_device_info *info);
  
  /**
   * amd_iommu_set_invalidate_ctx_cb() - Register a call-back for invalidating
   *				       a pasid context. This call-back is
   *				       invoked when the IOMMUv2 driver needs to
   *				       invalidate a PASID context, for example
   *				       because the task that is bound to that
   *				       context is about to exit.
   *
   * @pdev: The PCI device the call-back should be registered for
   * @cb: The call-back function
   */
  
  typedef void (*amd_iommu_invalidate_ctx)(struct pci_dev *pdev, int pasid);
  
  extern int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
  					   amd_iommu_invalidate_ctx cb);
  
  #else
  
  static inline int amd_iommu_detect(void) { return -ENODEV; }
  
  #endif
  
  #endif /* _ASM_X86_AMD_IOMMU_H */