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
27static unsigned int pasid_bits = 16;
28static const struct kfd2kgd_calls *kfd2kgd;
29
30bool 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
49unsigned int kfd_get_pasid_limit(void)
50{
51	return 1U << pasid_bits;
52}
53
54unsigned 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
80void kfd_pasid_free(unsigned int pasid)
81{
82	if (kfd2kgd)
83		amdgpu_pasid_free(pasid);
84}