xref: /linux/drivers/gpu/drm/v3d/v3d_bo.c (revision 226666556a9b3b51f04f9dad83662e5b9c78a325)
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 
18 #include <linux/dma-buf.h>
19 #include <linux/vmalloc.h>
20 
21 #include <drm/drm_print.h>
22 #include <drm/drm_timeout.h>
23 
24 #include "v3d_drv.h"
25 #include "uapi/drm/v3d_drm.h"
26 
27 static enum drm_gem_object_status v3d_gem_status(struct drm_gem_object *obj)
28 {
29 	struct v3d_bo *bo = to_v3d_bo(obj);
30 	enum drm_gem_object_status res = 0;
31 
32 	if (bo->base.pages)
33 		res |= DRM_GEM_OBJECT_RESIDENT;
34 
35 	return res;
36 }
37 
38 /* Called DRM core on the last userspace/kernel unreference of the
39  * BO.
40  */
41 void v3d_free_object(struct drm_gem_object *obj)
42 {
43 	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
44 	struct v3d_bo *bo = to_v3d_bo(obj);
45 
46 	if (bo->vaddr)
47 		v3d_put_bo_vaddr(bo);
48 
49 	v3d_mmu_remove_ptes(bo);
50 
51 	mutex_lock(&v3d->bo_lock);
52 	v3d->bo_stats.num_allocated--;
53 	v3d->bo_stats.pages_allocated -= obj->size >> V3D_MMU_PAGE_SHIFT;
54 	mutex_unlock(&v3d->bo_lock);
55 
56 	spin_lock(&v3d->mm_lock);
57 	drm_mm_remove_node(&bo->node);
58 	spin_unlock(&v3d->mm_lock);
59 
60 	/* GPU execution may have dirtied any pages in the BO. */
61 	bo->base.pages_mark_dirty_on_put = true;
62 
63 	drm_gem_shmem_free(&bo->base);
64 }
65 
66 static const struct drm_gem_object_funcs v3d_gem_funcs = {
67 	.free = v3d_free_object,
68 	.print_info = drm_gem_shmem_object_print_info,
69 	.pin = drm_gem_shmem_object_pin,
70 	.unpin = drm_gem_shmem_object_unpin,
71 	.get_sg_table = drm_gem_shmem_object_get_sg_table,
72 	.vmap = drm_gem_shmem_object_vmap,
73 	.vunmap = drm_gem_shmem_object_vunmap,
74 	.mmap = drm_gem_shmem_object_mmap,
75 	.status = v3d_gem_status,
76 	.vm_ops = &drm_gem_shmem_vm_ops,
77 };
78 
79 /* gem_create_object function for allocating a BO struct and doing
80  * early setup.
81  */
82 struct drm_gem_object *v3d_create_object(struct drm_device *dev, size_t size)
83 {
84 	struct v3d_bo *bo;
85 	struct drm_gem_object *obj;
86 
87 	if (size == 0)
88 		return ERR_PTR(-EINVAL);
89 
90 	bo = kzalloc_obj(*bo);
91 	if (!bo)
92 		return ERR_PTR(-ENOMEM);
93 	obj = &bo->base.base;
94 
95 	obj->funcs = &v3d_gem_funcs;
96 	bo->base.map_wc = true;
97 	INIT_LIST_HEAD(&bo->unref_head);
98 
99 	return &bo->base.base;
100 }
101 
102 static int
103 v3d_bo_create_finish(struct drm_gem_object *obj)
104 {
105 	struct v3d_dev *v3d = to_v3d_dev(obj->dev);
106 	struct v3d_bo *bo = to_v3d_bo(obj);
107 	struct sg_table *sgt;
108 	u64 align;
109 	int ret;
110 
111 	/* So far we pin the BO in the MMU for its lifetime, so use
112 	 * shmem's helper for getting a lifetime sgt.
113 	 */
114 	sgt = drm_gem_shmem_get_pages_sgt(&bo->base);
115 	if (IS_ERR(sgt))
116 		return PTR_ERR(sgt);
117 
118 	if (!drm_gem_get_huge_mnt(obj->dev))
119 		align = SZ_4K;
120 	else if (obj->size >= SZ_1M)
121 		align = SZ_1M;
122 	else if (obj->size >= SZ_64K)
123 		align = SZ_64K;
124 	else
125 		align = SZ_4K;
126 
127 	spin_lock(&v3d->mm_lock);
128 	/* Allocate the object's space in the GPU's page tables.
129 	 * Inserting PTEs will happen later, but the offset is for the
130 	 * lifetime of the BO.
131 	 */
132 	ret = drm_mm_insert_node_generic(&v3d->mm, &bo->node,
133 					 obj->size >> V3D_MMU_PAGE_SHIFT,
134 					 align >> V3D_MMU_PAGE_SHIFT, 0, 0);
135 	spin_unlock(&v3d->mm_lock);
136 	if (ret)
137 		return ret;
138 
139 	/* Track stats for /debug/dri/n/bo_stats. */
140 	mutex_lock(&v3d->bo_lock);
141 	v3d->bo_stats.num_allocated++;
142 	v3d->bo_stats.pages_allocated += obj->size >> V3D_MMU_PAGE_SHIFT;
143 	mutex_unlock(&v3d->bo_lock);
144 
145 	v3d_mmu_insert_ptes(bo);
146 
147 	return 0;
148 }
149 
150 struct v3d_bo *v3d_bo_create(struct drm_device *dev, struct drm_file *file_priv,
151 			     size_t unaligned_size)
152 {
153 	struct drm_gem_shmem_object *shmem_obj;
154 	struct v3d_bo *bo;
155 	int ret;
156 
157 	shmem_obj = drm_gem_shmem_create(dev, unaligned_size);
158 	if (IS_ERR(shmem_obj))
159 		return ERR_CAST(shmem_obj);
160 	bo = to_v3d_bo(&shmem_obj->base);
161 	bo->vaddr = NULL;
162 
163 	ret = v3d_bo_create_finish(&shmem_obj->base);
164 	if (ret)
165 		goto free_obj;
166 
167 	return bo;
168 
169 free_obj:
170 	drm_gem_shmem_free(shmem_obj);
171 	return ERR_PTR(ret);
172 }
173 
174 struct drm_gem_object *
175 v3d_prime_import_sg_table(struct drm_device *dev,
176 			  struct dma_buf_attachment *attach,
177 			  struct sg_table *sgt)
178 {
179 	struct drm_gem_object *obj;
180 	int ret;
181 
182 	obj = drm_gem_shmem_prime_import_sg_table(dev, attach, sgt);
183 	if (IS_ERR(obj))
184 		return obj;
185 
186 	ret = v3d_bo_create_finish(obj);
187 	if (ret) {
188 		drm_gem_shmem_free(&to_v3d_bo(obj)->base);
189 		return ERR_PTR(ret);
190 	}
191 
192 	return obj;
193 }
194 
195 void v3d_get_bo_vaddr(struct v3d_bo *bo)
196 {
197 	struct drm_gem_shmem_object *obj = &bo->base;
198 
199 	bo->vaddr = vmap(obj->pages, obj->base.size >> PAGE_SHIFT, VM_MAP,
200 			 pgprot_writecombine(PAGE_KERNEL));
201 }
202 
203 void v3d_put_bo_vaddr(struct v3d_bo *bo)
204 {
205 	vunmap(bo->vaddr);
206 	bo->vaddr = NULL;
207 }
208 
209 int v3d_create_bo_ioctl(struct drm_device *dev, void *data,
210 			struct drm_file *file_priv)
211 {
212 	struct drm_v3d_create_bo *args = data;
213 	struct v3d_bo *bo = NULL;
214 	int ret;
215 
216 	if (args->flags != 0) {
217 		drm_dbg(dev, "unknown create_bo flags: %d\n", args->flags);
218 		return -EINVAL;
219 	}
220 
221 	bo = v3d_bo_create(dev, file_priv, PAGE_ALIGN(args->size));
222 	if (IS_ERR(bo))
223 		return PTR_ERR(bo);
224 
225 	args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
226 
227 	ret = drm_gem_handle_create(file_priv, &bo->base.base, &args->handle);
228 	drm_gem_object_put(&bo->base.base);
229 
230 	return ret;
231 }
232 
233 int v3d_mmap_bo_ioctl(struct drm_device *dev, void *data,
234 		      struct drm_file *file_priv)
235 {
236 	struct drm_v3d_mmap_bo *args = data;
237 	struct drm_gem_object *gem_obj;
238 
239 	if (args->flags != 0) {
240 		drm_dbg(dev, "unknown mmap_bo flags: %d\n", args->flags);
241 		return -EINVAL;
242 	}
243 
244 	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
245 	if (!gem_obj) {
246 		drm_dbg(dev, "Failed to look up GEM BO %d\n", args->handle);
247 		return -ENOENT;
248 	}
249 
250 	args->offset = drm_vma_node_offset_addr(&gem_obj->vma_node);
251 	drm_gem_object_put(gem_obj);
252 
253 	return 0;
254 }
255 
256 int v3d_get_bo_offset_ioctl(struct drm_device *dev, void *data,
257 			    struct drm_file *file_priv)
258 {
259 	struct drm_v3d_get_bo_offset *args = data;
260 	struct drm_gem_object *gem_obj;
261 	struct v3d_bo *bo;
262 
263 	gem_obj = drm_gem_object_lookup(file_priv, args->handle);
264 	if (!gem_obj) {
265 		drm_dbg(dev, "Failed to look up GEM BO %d\n", args->handle);
266 		return -ENOENT;
267 	}
268 	bo = to_v3d_bo(gem_obj);
269 
270 	args->offset = bo->node.start << V3D_MMU_PAGE_SHIFT;
271 
272 	drm_gem_object_put(gem_obj);
273 	return 0;
274 }
275 
276 int
277 v3d_wait_bo_ioctl(struct drm_device *dev, void *data,
278 		  struct drm_file *file_priv)
279 {
280 	int ret;
281 	struct drm_v3d_wait_bo *args = data;
282 	ktime_t start = ktime_get();
283 	u64 delta_ns;
284 	unsigned long timeout_jiffies =
285 		drm_timeout_rel_to_jiffies(args->timeout_ns);
286 
287 	if (args->pad != 0)
288 		return -EINVAL;
289 
290 	ret = drm_gem_dma_resv_wait(file_priv, args->handle,
291 				    true, timeout_jiffies);
292 
293 	/* Decrement the user's timeout, in case we got interrupted
294 	 * such that the ioctl will be restarted.
295 	 */
296 	delta_ns = ktime_to_ns(ktime_sub(ktime_get(), start));
297 	if (delta_ns < args->timeout_ns)
298 		args->timeout_ns -= delta_ns;
299 	else
300 		args->timeout_ns = 0;
301 
302 	/* Asked to wait beyond the jiffy/scheduler precision? */
303 	if (ret == -ETIME && args->timeout_ns)
304 		ret = -EAGAIN;
305 
306 	return ret;
307 }
308