1// SPDX-License-Identifier: GPL-2.0 OR MIT
2/*
3 * Copyright 2014-2022 Advanced Micro Devices, Inc.
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
19 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
20 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
21 * OTHER DEALINGS IN THE SOFTWARE.
22 */
23
24#include <linux/types.h>
25#include "kfd_priv.h"
26#include "amdgpu_ids.h"
27
28static unsigned int pasid_bits = 16;
29static bool pasids_allocated; /* = false */
30
31bool kfd_set_pasid_limit(unsigned int new_limit)
32{
33 if (new_limit < 2)
34 return false;
35
36 if (new_limit < (1U << pasid_bits)) {
37 if (pasids_allocated)
38 /* We've already allocated user PASIDs, too late to
39 * change the limit
40 */
41 return false;
42
43 while (new_limit < (1U << pasid_bits))
44 pasid_bits--;
45 }
46
47 return true;
48}
49
50unsigned int kfd_get_pasid_limit(void)
51{
52 return 1U << pasid_bits;
53}
54
55u32 kfd_pasid_alloc(void)
56{
57 int r = amdgpu_pasid_alloc(bits: pasid_bits);
58
59 if (r > 0) {
60 pasids_allocated = true;
61 return r;
62 }
63
64 return 0;
65}
66
67void kfd_pasid_free(u32 pasid)
68{
69 amdgpu_pasid_free(pasid);
70}
71

source code of linux/drivers/gpu/drm/amd/amdkfd/kfd_pasid.c