1 /*
2 * Copyright 2014 Advanced Micro Devices, Inc.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
17 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
18 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
19 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
20 * OTHER DEALINGS IN THE SOFTWARE.
21 */
22
23 #include <linux/types.h>
24 #include "kfd_priv.h"
25 #include "amdgpu_ids.h"
26
27 static unsigned int pasid_bits = 16;
28 static const struct kfd2kgd_calls *kfd2kgd;
29
30 bool kfd_set_pasid_limit(unsigned int new_limit)
31 {
32 if (new_limit < 2)
33 return false;
34
35 if (new_limit < (1U << pasid_bits)) {
36 if (kfd2kgd)
37 /* We've already allocated user PASIDs, too late to
38 * change the limit
39 */
40 return false;
41
42 while (new_limit < (1U << pasid_bits))
43 pasid_bits--;
44 }
45
46 return true;
47 }
48
49 unsigned int kfd_get_pasid_limit(void)
50 {
51 return 1U << pasid_bits;
52 }
53
54 unsigned int kfd_pasid_alloc(void)
55 {
56 int r;
57
58 /* Find the first best KFD device for calling KGD */
59 if (!kfd2kgd) {
60 struct kfd_dev *dev = NULL;
61 unsigned int i = 0;
62
63 while ((kfd_topology_enum_kfd_devices(i, &dev)) == 0) {
64 if (dev && dev->kfd2kgd) {
65 kfd2kgd = dev->kfd2kgd;
66 break;
67 }
68 i++;
69 }
70
71 if (!kfd2kgd)
72 return false;
73 }
74
75 r = amdgpu_pasid_alloc(pasid_bits);
76
77 return r > 0 ? r : 0;
78 }
79
80 void kfd_pasid_free(unsigned int pasid)
81 {
82 if (kfd2kgd)
83 amdgpu_pasid_free(pasid);
84 }