1 /*
2  * Copyright (C) 2007-2010 Advanced Micro Devices, Inc.
3  * Author: Joerg Roedel <joerg.roedel@amd.com>
4  *         Leo Duran <leo.duran@amd.com>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License version 2 as published
8  * by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program; if not, write to the Free Software
17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
18  */
19 
20 #ifndef _ASM_X86_AMD_IOMMU_H
21 #define _ASM_X86_AMD_IOMMU_H
22 
23 #include <linux/types.h>
24 
25 #ifdef CONFIG_AMD_IOMMU
26 
27 struct task_struct;
28 struct pci_dev;
29 
30 extern int amd_iommu_detect(void);
31 extern int amd_iommu_init_hardware(void);
32 
33 /**
34  * amd_iommu_enable_device_erratum() - Enable erratum workaround for device
35  *				       in the IOMMUv2 driver
36  * @pdev: The PCI device the workaround is necessary for
37  * @erratum: The erratum workaround to enable
38  *
39  * The function needs to be called before amd_iommu_init_device().
40  * Possible values for the erratum number are for now:
41  * - AMD_PRI_DEV_ERRATUM_ENABLE_RESET - Reset PRI capability when PRI
42  *					is enabled
43  * - AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE - Limit number of outstanding PRI
44  *					 requests to one
45  */
46 #define AMD_PRI_DEV_ERRATUM_ENABLE_RESET		0
47 #define AMD_PRI_DEV_ERRATUM_LIMIT_REQ_ONE		1
48 
49 extern void amd_iommu_enable_device_erratum(struct pci_dev *pdev, u32 erratum);
50 
51 /**
52  * amd_iommu_init_device() - Init device for use with IOMMUv2 driver
53  * @pdev: The PCI device to initialize
54  * @pasids: Number of PASIDs to support for this device
55  *
56  * This function does all setup for the device pdev so that it can be
57  * used with IOMMUv2.
58  * Returns 0 on success or negative value on error.
59  */
60 extern int amd_iommu_init_device(struct pci_dev *pdev, int pasids);
61 
62 /**
63  * amd_iommu_free_device() - Free all IOMMUv2 related device resources
64  *			     and disable IOMMUv2 usage for this device
65  * @pdev: The PCI device to disable IOMMUv2 usage for'
66  */
67 extern void amd_iommu_free_device(struct pci_dev *pdev);
68 
69 /**
70  * amd_iommu_bind_pasid() - Bind a given task to a PASID on a device
71  * @pdev: The PCI device to bind the task to
72  * @pasid: The PASID on the device the task should be bound to
73  * @task: the task to bind
74  *
75  * The function returns 0 on success or a negative value on error.
76  */
77 extern int amd_iommu_bind_pasid(struct pci_dev *pdev, int pasid,
78 				struct task_struct *task);
79 
80 /**
81  * amd_iommu_unbind_pasid() - Unbind a PASID from its task on
82  *			      a device
83  * @pdev: The device of the PASID
84  * @pasid: The PASID to unbind
85  *
86  * When this function returns the device is no longer using the PASID
87  * and the PASID is no longer bound to its task.
88  */
89 extern void amd_iommu_unbind_pasid(struct pci_dev *pdev, int pasid);
90 
91 /**
92  * amd_iommu_set_invalid_ppr_cb() - Register a call-back for failed
93  *				    PRI requests
94  * @pdev: The PCI device the call-back should be registered for
95  * @cb: The call-back function
96  *
97  * The IOMMUv2 driver invokes this call-back when it is unable to
98  * successfully handle a PRI request. The device driver can then decide
99  * which PRI response the device should see. Possible return values for
100  * the call-back are:
101  *
102  * - AMD_IOMMU_INV_PRI_RSP_SUCCESS - Send SUCCESS back to the device
103  * - AMD_IOMMU_INV_PRI_RSP_INVALID - Send INVALID back to the device
104  * - AMD_IOMMU_INV_PRI_RSP_FAIL    - Send Failure back to the device,
105  *				     the device is required to disable
106  *				     PRI when it receives this response
107  *
108  * The function returns 0 on success or negative value on error.
109  */
110 #define AMD_IOMMU_INV_PRI_RSP_SUCCESS	0
111 #define AMD_IOMMU_INV_PRI_RSP_INVALID	1
112 #define AMD_IOMMU_INV_PRI_RSP_FAIL	2
113 
114 typedef int (*amd_iommu_invalid_ppr_cb)(struct pci_dev *pdev,
115 					int pasid,
116 					unsigned long address,
117 					u16);
118 
119 extern int amd_iommu_set_invalid_ppr_cb(struct pci_dev *pdev,
120 					amd_iommu_invalid_ppr_cb cb);
121 
122 /**
123  * amd_iommu_device_info() - Get information about IOMMUv2 support of a
124  *			     PCI device
125  * @pdev: PCI device to query information from
126  * @info: A pointer to an amd_iommu_device_info structure which will contain
127  *	  the information about the PCI device
128  *
129  * Returns 0 on success, negative value on error
130  */
131 
132 #define AMD_IOMMU_DEVICE_FLAG_ATS_SUP     0x1    /* ATS feature supported */
133 #define AMD_IOMMU_DEVICE_FLAG_PRI_SUP     0x2    /* PRI feature supported */
134 #define AMD_IOMMU_DEVICE_FLAG_PASID_SUP   0x4    /* PASID context supported */
135 #define AMD_IOMMU_DEVICE_FLAG_EXEC_SUP    0x8    /* Device may request execution
136 						    on memory pages */
137 #define AMD_IOMMU_DEVICE_FLAG_PRIV_SUP   0x10    /* Device may request
138 						    super-user privileges */
139 
140 struct amd_iommu_device_info {
141 	int max_pasids;
142 	u32 flags;
143 };
144 
145 extern int amd_iommu_device_info(struct pci_dev *pdev,
146 				 struct amd_iommu_device_info *info);
147 
148 /**
149  * amd_iommu_set_invalidate_ctx_cb() - Register a call-back for invalidating
150  *				       a pasid context. This call-back is
151  *				       invoked when the IOMMUv2 driver needs to
152  *				       invalidate a PASID context, for example
153  *				       because the task that is bound to that
154  *				       context is about to exit.
155  *
156  * @pdev: The PCI device the call-back should be registered for
157  * @cb: The call-back function
158  */
159 
160 typedef void (*amd_iommu_invalidate_ctx)(struct pci_dev *pdev, int pasid);
161 
162 extern int amd_iommu_set_invalidate_ctx_cb(struct pci_dev *pdev,
163 					   amd_iommu_invalidate_ctx cb);
164 
165 #else
166 
amd_iommu_detect(void)167 static inline int amd_iommu_detect(void) { return -ENODEV; }
168 
169 #endif
170 
171 #endif /* _ASM_X86_AMD_IOMMU_H */
172