1 // SPDX-License-Identifier: GPL-2.0+
2 /* Copyright (C) 2015-2018 Broadcom */
3
4 /**
5 * DOC: V3D GEM BO management support
6 *
7 * Compared to VC4 (V3D 2.x), V3D 3.3 introduces an MMU between the
8 * GPU and the bus, allowing us to use shmem objects for our storage
9 * instead of CMA.
10 *
11 * Physically contiguous objects may still be imported to V3D, but the
12 * driver doesn't allocate physically contiguous objects on its own.
13 * Display engines requiring physically contiguous allocations should
14 * look into Mesa's "renderonly" support (as used by the Mesa pl111
15 * driver) for an example of how to integrate with V3D.
16 *
17 * Long term, we should support evicting pages from the MMU when under
18 * memory pressure (thus the v3d_bo_get_pages() refcounting), but
19 * that's not a high priority since our systems tend to not have swap.
20 */
21
22 #include <linux/dma-buf.h>
23 #include <linux/pfn_t.h>
24
25 #include "v3d_drv.h"
26 #include "uapi/drm/v3d_drm.h"
27
28 /* Called DRM core on the last userspace/kernel unreference of the
29 * BO.
30 */
v3d_free_object(struct drm_gem_object * obj)31 void v3d_free_object(struct drm_gem_object *obj)
32 {
33 struct v3d_dev *v3d = to_v3d_dev(obj->dev);
34 struct v3d_bo *bo = to_v3d_bo(obj);
35
36 v3d_mmu_remove_ptes(bo);
37
38 mutex_lock(&v3d->bo_lock);
39 v3d->bo_stats.num_allocated--;
40 v3d->bo_stats.pages_allocated -= obj->size >> PAGE_SHIFT;
41 mutex_unlock(&v3d->bo_lock);
42
43 spin_lock(&v3d->mm_lock);
44 drm_mm_remove_node(&bo->node);
45 spin_unlock(&v3d->mm_lock);
46
47 /* GPU execution may have dirtied any pages in the BO. */
48 bo->base.pages_mark_dirty_on_put = true;
49
50 drm_gem_shmem_free(&bo->base);
51 }
52
53 static const struct drm_gem_object_funcs v3d_gem_funcs = {
54 .free = v3d_free_object,
55 .print_info = drm_gem_shmem_object_print_info,
56 .pin = drm_gem_shmem_object_pin,
57 .unpin = drm_gem_shmem_object_unpin,
58 .get_sg_table = drm_gem_shmem_object_get_sg_table,
59 .vmap = drm_gem_shmem_object_vmap,
60 .vunmap = drm_gem_shmem_object_vunmap,
61 .mmap = drm_gem_shmem_object_mmap,
62 .vm_ops = &drm_gem_shmem_vm_ops,
63 };
64
65 /* gem_create_object function for allocating a BO struct and doing
66 * early setup.
67 */
v3d_create_object(struct drm_device * dev,size_t size)68 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
69 {
70 struct v3d_bo *bo;
71 struct drm_gem_object *obj;
72
73 if (size == 0)
74 return ERR_PTR(-EINVAL);
75
76 bo = kzalloc(sizeof(*bo), GFP_KERNEL);
77 if (!bo)
78 return ERR_PTR(-ENOMEM);
79 obj = &bo->base.base;
80
81 obj->funcs = &v3d_gem_funcs;
82 bo->base.map_wc = true;
83 INIT_LIST_HEAD(&bo->unref_head);
84
85 return &bo->base.base;
86 }
87
88 static int
v3d_bo_create_finish(struct drm_gem_object * obj)89 v3d_bo_create_finish(struct drm_gem_object *obj)
90 {
91 struct v3d_dev *v3d = to_v3d_dev(obj->dev);
92 struct v3d_bo *bo = to_v3d_bo(obj);
93 struct sg_table *sgt;
94 int ret;
95
96 /* So far we pin the BO in the MMU for its lifetime, so use
97 * shmem's helper for getting a lifetime sgt.
98 */
99 sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
100 if (IS_ERR(sgt))
101 return PTR_ERR(sgt);
102
103 spin_lock(&v3d->mm_lock);
104 /* Allocate the object's space in the GPU's page tables.
105 * Inserting PTEs will happen later, but the offset is for the
106 * lifetime of the BO.
107 */
108 ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
109 obj->size >> PAGE_SHIFT,
110 GMP_GRANULARITY >> PAGE_SHIFT, 0, 0);
111 spin_unlock(&v3d->mm_lock);
112 if (ret)
113 return ret;
114
115 /* Track stats for /debug/dri/n/bo_stats. */
116 mutex_lock(&v3d->bo_lock);
117 v3d->bo_stats.num_allocated++;
118 v3d->bo_stats.pages_allocated += obj->size >> PAGE_SHIFT;
119 mutex_unlock(&v3d->bo_lock);
120
121 v3d_mmu_insert_ptes(bo);
122
123 return 0;
124 }
125
v3d_bo_create(struct drm_device * dev,struct drm_file * file_priv,size_t unaligned_size)126 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
127 size_t unaligned_size)
128 {
129 struct drm_gem_shmem_object *shmem_obj;
130 struct v3d_bo *bo;
131 int ret;
132
133 shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
134 if (IS_ERR(shmem_obj))
135 return ERR_CAST(shmem_obj);
136 bo = to_v3d_bo(&shmem_obj->base);
137
138 ret = v3d_bo_create_finish(&shmem_obj->base);
139 if (ret)
140 goto free_obj;
141
142 return bo;
143
144 free_obj:
145 drm_gem_shmem_free(shmem_obj);
146 return ERR_PTR(ret);
147 }
148
149 struct drm_gem_object *
v3d_prime_import_sg_table(struct drm_device * dev,struct dma_buf_attachment * attach,struct sg_table * sgt)150 v3d_prime_import_sg_table(struct drm_device *dev,
151 struct dma_buf_attachment *attach,
152 struct sg_table *sgt)
153 {
154 struct drm_gem_object *obj;
155 int ret;
156
157 obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
158 if (IS_ERR(obj))
159 return obj;
160
161 ret = v3d_bo_create_finish(obj);
162 if (ret) {
163 drm_gem_shmem_free(&to_v3d_bo(obj)->base);
164 return ERR_PTR(ret);
165 }
166
167 return obj;
168 }
169
v3d_create_bo_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)170 int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
171 struct drm_file *file_priv)
172 {
173 struct drm_v3d_create_bo *args = data;
174 struct v3d_bo *bo = NULL;
175 int ret;
176
177 if (args->flags != 0) {
178 DRM_INFO("unknown create_bo flags: %d\n", args->flags);
179 return -EINVAL;
180 }
181
182 bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
183 if (IS_ERR(bo))
184 return PTR_ERR(bo);
185
186 args->offset = bo->node.start << PAGE_SHIFT;
187
188 ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
189 drm_gem_object_put(&bo->base.base);
190
191 return ret;
192 }
193
v3d_mmap_bo_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)194 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
195 struct drm_file *file_priv)
196 {
197 struct drm_v3d_mmap_bo *args = data;
198 struct drm_gem_object *gem_obj;
199
200 if (args->flags != 0) {
201 DRM_INFO("unknown mmap_bo flags: %d\n", args->flags);
202 return -EINVAL;
203 }
204
205 gem_obj = drm_gem_object_lookup(file_priv, args->handle);
206 if (!gem_obj) {
207 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
208 return -ENOENT;
209 }
210
211 args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
212 drm_gem_object_put(gem_obj);
213
214 return 0;
215 }
216
v3d_get_bo_offset_ioctl(struct drm_device * dev,void * data,struct drm_file * file_priv)217 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
218 struct drm_file *file_priv)
219 {
220 struct drm_v3d_get_bo_offset *args = data;
221 struct drm_gem_object *gem_obj;
222 struct v3d_bo *bo;
223
224 gem_obj = drm_gem_object_lookup(file_priv, args->handle);
225 if (!gem_obj) {
226 DRM_DEBUG("Failed to look up GEM BO %d\n", args->handle);
227 return -ENOENT;
228 }
229 bo = to_v3d_bo(gem_obj);
230
231 args->offset = bo->node.start << PAGE_SHIFT;
232
233 drm_gem_object_put(gem_obj);
234 return 0;
235 }
236