1 /* $NetBSD: kfd_pasid.c,v 1.3 2021/12/18 23:44:59 riastradh Exp $ */
2
3 /*
4 * Copyright 2014 Advanced Micro Devices, Inc.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
23 */
24
25 #include <sys/cdefs.h>
26 __KERNEL_RCSID(0, "$NetBSD: kfd_pasid.c,v 1.3 2021/12/18 23:44:59 riastradh Exp $");
27
28 #include <linux/types.h>
29 #include "kfd_priv.h"
30 #include "amdgpu_ids.h"
31
32 static unsigned int pasid_bits = 16;
33 static const struct kfd2kgd_calls *kfd2kgd;
34
kfd_set_pasid_limit(unsigned int new_limit)35 bool kfd_set_pasid_limit(unsigned int new_limit)
36 {
37 if (new_limit < 2)
38 return false;
39
40 if (new_limit < (1U << pasid_bits)) {
41 if (kfd2kgd)
42 /* We've already allocated user PASIDs, too late to
43 * change the limit
44 */
45 return false;
46
47 while (new_limit < (1U << pasid_bits))
48 pasid_bits--;
49 }
50
51 return true;
52 }
53
kfd_get_pasid_limit(void)54 unsigned int kfd_get_pasid_limit(void)
55 {
56 return 1U << pasid_bits;
57 }
58
kfd_pasid_alloc(void)59 unsigned int kfd_pasid_alloc(void)
60 {
61 int r;
62
63 /* Find the first best KFD device for calling KGD */
64 if (!kfd2kgd) {
65 struct kfd_dev *dev = NULL;
66 unsigned int i = 0;
67
68 while ((kfd_topology_enum_kfd_devices(i, &dev)) == 0) {
69 if (dev && dev->kfd2kgd) {
70 kfd2kgd = dev->kfd2kgd;
71 break;
72 }
73 i++;
74 }
75
76 if (!kfd2kgd)
77 return false;
78 }
79
80 r = amdgpu_pasid_alloc(pasid_bits);
81
82 return r > 0 ? r : 0;
83 }
84
kfd_pasid_free(unsigned int pasid)85 void kfd_pasid_free(unsigned int pasid)
86 {
87 if (kfd2kgd)
88 amdgpu_pasid_free(pasid);
89 }
90