1 // SPDX-License-Identifier: GPL-2.0 OR MIT
2 /*
3  * Copyright 2016-2021 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  * Authors: Christian König, Felix Kuehling
24  */
25 
26 #include "amdgpu.h"
27 
28 /**
29  * DOC: mem_info_preempt_used
30  *
31  * The amdgpu driver provides a sysfs API for reporting current total amount of
32  * used preemptible memory.
33  * The file mem_info_preempt_used is used for this, and returns the current
34  * used size of the preemptible block, in bytes
35  */
36 static ssize_t mem_info_preempt_used_show(struct device *dev,
37 					  struct device_attribute *attr,
38 					  char *buf)
39 {
40 	struct drm_device *ddev = dev_get_drvdata(dev);
41 	struct amdgpu_device *adev = drm_to_adev(ddev);
42 	struct ttm_resource_manager *man = &adev->mman.preempt_mgr;
43 
44 	return sysfs_emit(buf, "%llu\n", ttm_resource_manager_usage(man));
45 }
46 
47 static DEVICE_ATTR_RO(mem_info_preempt_used);
48 
49 /**
50  * amdgpu_preempt_mgr_new - allocate a new node
51  *
52  * @man: TTM memory type manager
53  * @tbo: TTM BO we need this range for
54  * @place: placement flags and restrictions
55  * @res: TTM memory object
56  *
57  * Dummy, just count the space used without allocating resources or any limit.
58  */
59 static int amdgpu_preempt_mgr_new(struct ttm_resource_manager *man,
60 				  struct ttm_buffer_object *tbo,
61 				  const struct ttm_place *place,
62 				  struct ttm_resource **res)
63 {
64 	*res = kzalloc(sizeof(**res), GFP_KERNEL);
65 	if (!*res)
66 		return -ENOMEM;
67 
68 	ttm_resource_init(tbo, place, *res);
69 	(*res)->start = AMDGPU_BO_INVALID_OFFSET;
70 	return 0;
71 }
72 
73 /**
74  * amdgpu_preempt_mgr_del - free ranges
75  *
76  * @man: TTM memory type manager
77  * @res: TTM memory object
78  *
79  * Free the allocated GTT again.
80  */
81 static void amdgpu_preempt_mgr_del(struct ttm_resource_manager *man,
82 				   struct ttm_resource *res)
83 {
84 	ttm_resource_fini(man, res);
85 	kfree(res);
86 }
87 
88 static const struct ttm_resource_manager_func amdgpu_preempt_mgr_func = {
89 	.alloc = amdgpu_preempt_mgr_new,
90 	.free = amdgpu_preempt_mgr_del,
91 };
92 
93 /**
94  * amdgpu_preempt_mgr_init - init PREEMPT manager and DRM MM
95  *
96  * @adev: amdgpu_device pointer
97  *
98  * Allocate and initialize the GTT manager.
99  */
100 int amdgpu_preempt_mgr_init(struct amdgpu_device *adev)
101 {
102 	struct ttm_resource_manager *man = &adev->mman.preempt_mgr;
103 	int ret;
104 
105 	man->use_tt = true;
106 	man->func = &amdgpu_preempt_mgr_func;
107 
108 	ttm_resource_manager_init(man, &adev->mman.bdev, (1 << 30));
109 
110 	ret = device_create_file(adev->dev, &dev_attr_mem_info_preempt_used);
111 	if (ret) {
112 		DRM_ERROR("Failed to create device file mem_info_preempt_used\n");
113 		return ret;
114 	}
115 
116 	ttm_set_driver_manager(&adev->mman.bdev, AMDGPU_PL_PREEMPT, man);
117 	ttm_resource_manager_set_used(man, true);
118 	return 0;
119 }
120 
121 /**
122  * amdgpu_preempt_mgr_fini - free and destroy GTT manager
123  *
124  * @adev: amdgpu_device pointer
125  *
126  * Destroy and free the GTT manager, returns -EBUSY if ranges are still
127  * allocated inside it.
128  */
129 void amdgpu_preempt_mgr_fini(struct amdgpu_device *adev)
130 {
131 	struct ttm_resource_manager *man = &adev->mman.preempt_mgr;
132 	int ret;
133 
134 	ttm_resource_manager_set_used(man, false);
135 
136 	ret = ttm_resource_manager_evict_all(&adev->mman.bdev, man);
137 	if (ret)
138 		return;
139 
140 	device_remove_file(adev->dev, &dev_attr_mem_info_preempt_used);
141 
142 	ttm_resource_manager_cleanup(man);
143 	ttm_set_driver_manager(&adev->mman.bdev, AMDGPU_PL_PREEMPT, NULL);
144 }
145